removed early return on error when checking dispenser status in the start and final loops

config/config.go

@@ -5,28 +5,31 @@ import (
 	"os"
 	"strings"
 
-	"gitea.futuresens.co.uk/futuresens/hardlink/handlers"
+	"gitea.futuresens.co.uk/futuresens/hardlink/errorhandlers"
 	log "github.com/sirupsen/logrus"
 	yaml "gopkg.in/yaml.v3"
 )
 
 // configRec holds values from config.yml.
 type ConfigRec struct {
-	Port           int    `yaml:"port"`
-	LockserverUrl  string `yaml:"lockservUrl"`
-	LockType       string `yaml:"lockType"`
-	EncoderAddress string `yaml:"encoderAddr"`
-	Cert           string `yaml:"cert"`
-	DispenserPort  string `yaml:"dispensPort"`
-	DispenserAdrr  string `yaml:"dispensAddr"`
-	PrinterName    string `yaml:"printerName"`
-	LogDir         string `yaml:"logdir"`
-	Dbport         int    `yaml:"dbport"`     // Port for the database connection
-	Dbname         string `yaml:"dbname"`     // Database name for the connection
-	Dbuser         string `yaml:"dbuser"`     // User for the database connection
-	Dbpassword     string `yaml:"dbpassword"` // Password for the database connection
-	IsPayment      bool   `yaml:"isPayment"`
-	TestMode       bool   `yaml:"testMode"`
+	Port            int      `yaml:"port"`
+	LockserverUrl   string   `yaml:"lockservUrl"`
+	LockType        string   `yaml:"lockType"`
+	EncoderAddress  string   `yaml:"encoderAddr"`
+	Cert            string   `yaml:"cert"`
+	DispenserPort   string   `yaml:"dispensPort"`
+	DispenserAdrr   string   `yaml:"dispensAddr"`
+	PrinterName     string   `yaml:"printerName"`
+	LogDir          string   `yaml:"logdir"`
+	Dbport          int      `yaml:"dbport"`     // Port for the database connection
+	Dbname          string   `yaml:"dbname"`     // Database name for the connection
+	Dbuser          string   `yaml:"dbuser"`     // User for the database connection
+	Dbpassword      string   `yaml:"dbpassword"` // Password for the database connection
+	IsPayment       bool     `yaml:"isPayment"`
+	TestMode        bool     `yaml:"testMode"`
+	Hotel           string   `yaml:"hotel"`
+	Kiosk           int      `yaml:"kiosk"`
+	SendErrorEmails []string `yaml:"senderroremails"`
 }
 
 // ReadConfig reads config.yml and applies defaults.
@@ -49,7 +52,7 @@ func ReadHardlinkConfig() ConfigRec {
 
 	if cfg.LockType == "" {
 		err = fmt.Errorf("LockType is required in %s", configName)
-		handlers.FatalError(err)
+		errorhandlers.FatalError(err)
 	}
 	cfg.LockType = strings.ToLower(cfg.LockType)
 
@@ -81,7 +84,7 @@ func ReadPreauthReleaserConfig() ConfigRec {
 
 	if cfg.Dbport <= 0 || cfg.Dbuser == "" || cfg.Dbname == "" || cfg.Dbpassword == "" {
 		err = fmt.Errorf("Database config (dbport, dbuser, dbname, dbpassword) are required in %s", configName)
-		handlers.FatalError(err)
+		errorhandlers.FatalError(err)
 	}
 
 	if cfg.LogDir == "" {

db/db.go

@@ -198,3 +198,4 @@ WHERE TxnReference = @TxnReference AND Released = 0;
 	log.Infof("Marked preauth %s released at %s", txnReference, releasedAt.Format(time.RFC3339))
 	return nil
 }
+

dispenser/dispenser.go

@@ -1,9 +1,8 @@
 package dispenser
 
 import (
-	// "encoding/hex"
 	"fmt"
-	// "log"
+	"strings"
 	"time"
 
 	log "github.com/sirupsen/logrus"
@@ -20,29 +19,26 @@ const (
 	space    = 0x00                   // Space character
 	baudRate = 9600                   // Baud rate for serial communication
 	delay    = 500 * time.Millisecond // Delay for processing commands
-)
 
-// type (
-// 	configRec struct {
-// 		SerialPort string `yaml:"port"`
-// 		Address    string `yaml:"addr"`
-// 	}
-// )
+	// cache freshness for "continuous status" reads (tune as you wish)
+	defaultStatusTTL = 1500 * time.Millisecond
+)
 
 var (
 	SerialPort string
 	Address    []byte
-	commandFC7 = []byte{ETX, 0x46, 0x43, 0x37} // "FC7" command dispense card at read card position
-	commandFC0 = []byte{ETX, 0x46, 0x43, 0x30} // "FC0" command dispense card out of card mouth command
+
+	commandFC7 = []byte{ETX, 0x46, 0x43, 0x37} // "FC7"
+	commandFC0 = []byte{ETX, 0x46, 0x43, 0x30} // "FC0"
 
 	statusPos0 = map[byte]string{
 		0x38: "Keep",
 		0x34: "Command cannot execute",
 		0x32: "Preparing card fails",
 		0x31: "Preparing card",
-		0x30: "Normal", // Default if none of the above
+		0x30: "Normal",
+		0x36: "Command cannot execute; Preparing card fails",
 	}
-
 	statusPos1 = map[byte]string{
 		0x38: "Dispensing card",
 		0x34: "Capturing card",
@@ -50,7 +46,6 @@ var (
 		0x31: "Capture card error",
 		0x30: "Normal",
 	}
-
 	statusPos2 = map[byte]string{
 		0x38: "No captured card",
 		0x34: "Card overlapped",
@@ -58,7 +53,6 @@ var (
 		0x31: "Card pre-empty",
 		0x30: "Normal",
 	}
-
 	statusPos3 = map[byte]string{
 		0x38: "Card empty",
 		0x34: "Card ready position",
@@ -69,48 +63,80 @@ var (
 	}
 )
 
-func checkStatus(statusResp []byte) ([]string, error) {
-	if len(statusResp) > 3 {
-		statusBytes := statusResp[7:11] // Extract the relevant bytes from the response
-		// For each position, get the ASCII character, hex value, and mapped meaning.
-		posStatus := []struct {
-			pos    int
-			value  byte
-			mapper map[byte]string
-		}{
-			{pos: 1, value: statusBytes[0], mapper: statusPos0},
-			{pos: 2, value: statusBytes[1], mapper: statusPos1},
-			{pos: 3, value: statusBytes[2], mapper: statusPos2},
-			{pos: 4, value: statusBytes[3], mapper: statusPos3},
-		}
+// --------------------
+// Status helpers
+// --------------------
 
-		result := make([]string, len(posStatus))
-		for _, p := range posStatus {
-			statusMsg, exists := p.mapper[p.value]
-			if !exists {
-				statusMsg = "Unknown status"
-			}
-			if p.value != 0x30 {
-				result = append(result, fmt.Sprintf("Status: %s; ", statusMsg))
-			}
-			if p.pos == 4 && p.value == 0x38 {
-				return nil, fmt.Errorf("Card well empty")
-			}
-		}
-		return result, nil
+func logStatus(statusBytes []byte) {
+	if len(statusBytes) < 4 {
+		log.Infof("Dispenser status: <invalid len=%d>", len(statusBytes))
+		return
+	}
 
-	} else {
-		if len(statusResp) == 3 && statusResp[0] == ACK && statusResp[1] == Address[0] && statusResp[2] == Address[1] {
-			return "active;", nil
-		} else if len(statusResp) > 0 && statusResp[0] == NAK {
-			return "", fmt.Errorf("negative response from dispenser")
-		} else {
-			return "", fmt.Errorf("unexpected response status: % X", statusResp)
+	posStatus := []struct {
+		pos    int
+		value  byte
+		mapper map[byte]string
+	}{
+		{pos: 1, value: statusBytes[0], mapper: statusPos0},
+		{pos: 2, value: statusBytes[1], mapper: statusPos1},
+		{pos: 3, value: statusBytes[2], mapper: statusPos2},
+		{pos: 4, value: statusBytes[3], mapper: statusPos3},
+	}
+
+	var result strings.Builder
+	for _, p := range posStatus {
+		statusMsg, exists := p.mapper[p.value]
+		if !exists {
+			statusMsg = fmt.Sprintf("Unknown status 0x%X at position %d", p.value, p.pos)
+		}
+		if p.value != 0x30 {
+			result.WriteString(statusMsg + "; ")
 		}
 	}
+	log.Infof("Dispenser status: %s", result.String())
 }
 
-// calculateBCC computes the Block Check Character (BCC) as the XOR of all bytes from STX to ETX.
+func isAtEncoderPosition(statusBytes []byte) bool {
+	return len(statusBytes) >= 4 && statusBytes[3] == 0x33
+}
+
+func stockTake(statusBytes []byte) string {
+	if len(statusBytes) < 4 {
+		return ""
+	}
+	status := ""
+	if statusBytes[0] == 0x32 || statusBytes[0] == 0x36 {
+		status = statusPos0[statusBytes[0]]
+	}
+	if statusBytes[2] != 0x30 {
+		status = statusPos2[statusBytes[2]]
+	}
+	if statusBytes[3] == 0x38 {
+		status = statusPos3[statusBytes[3]]
+	}
+	return status
+}
+
+func isCardWellEmpty(statusBytes []byte) bool {
+	return len(statusBytes) >= 4 && statusBytes[3] == 0x38
+}
+
+func checkACK(statusResp []byte) error {
+	if len(statusResp) == 3 &&
+		statusResp[0] == ACK &&
+		len(Address) >= 2 &&
+		statusResp[1] == Address[0] &&
+		statusResp[2] == Address[1] {
+		return nil
+	}
+	if len(statusResp) > 0 && statusResp[0] == NAK {
+		return fmt.Errorf("negative response from dispenser")
+	}
+	return fmt.Errorf("unexpected response status: % X", statusResp)
+}
+
+// calculateBCC computes BCC as XOR of all bytes from STX to ETX.
 func calculateBCC(data []byte) byte {
 	var bcc byte
 	for _, b := range data {
@@ -121,8 +147,8 @@ func calculateBCC(data []byte) byte {
 
 func createPacket(address []byte, command []byte) []byte {
 	packet := []byte{STX}
-	packet = append(packet, address...) // Address bytes
-	packet = append(packet, space)      // Space character
+	packet = append(packet, address...)
+	packet = append(packet, space)
 	packet = append(packet, command...)
 	packet = append(packet, ETX)
 	bcc := calculateBCC(packet)
@@ -130,165 +156,134 @@ func createPacket(address []byte, command []byte) []byte {
 	return packet
 }
 
-func buildCheckRF(address []byte) []byte {
-	return createPacket(address, []byte{STX, 0x52, 0x46})
-}
-
-func buildCheckAP(address []byte) []byte {
-	return createPacket(address, []byte{STX, 0x41, 0x50})
-}
+func buildCheckAP(address []byte) []byte { return createPacket(address, []byte{STX, 0x41, 0x50}) }
 
 func sendAndReceive(port *serial.Port, packet []byte, delay time.Duration) ([]byte, error) {
-	n, err := port.Write(packet)
+	_, err := port.Write(packet)
 	if err != nil {
 		return nil, fmt.Errorf("error writing to port: %w", err)
 	}
-	// log.Printf("TX %d bytes: % X", n, packet[:n])
 
-	time.Sleep(delay) // Wait for the dispenser to process the command
+	time.Sleep(delay)
 
 	buf := make([]byte, 128)
-	n, err = port.Read(buf)
+	n, err := port.Read(buf)
 	if err != nil {
 		return nil, fmt.Errorf("error reading from port: %w", err)
 	}
-	resp := buf[:n]
-	// log.Printf("RX %d bytes: % X", n, buf[:n])
-	return resp, nil
+	return buf[:n], nil
 }
 
+// --------------------
+// Serial init (3 attempts)
+// --------------------
+
 func InitializeDispenser() (*serial.Port, error) {
-	const funcName = "initializeDispenser"
+	const (
+		funcName   = "InitializeDispenser"
+		maxRetries = 3
+		retryDelay = 4 * time.Second
+	)
+
+	if SerialPort == "" {
+		return nil, fmt.Errorf("%s: SerialPort is empty", funcName)
+	}
+	if len(Address) < 2 {
+		return nil, fmt.Errorf("%s: Address must be at least 2 bytes", funcName)
+	}
+
 	serialConfig := &serial.Config{
 		Name:        SerialPort,
 		Baud:        baudRate,
-		ReadTimeout: time.Second * 2,
+		ReadTimeout: 2 * time.Second,
 	}
-	port, err := serial.OpenPort(serialConfig)
-	if err != nil {
-		return nil, fmt.Errorf("error opening dispenser COM port: %w", err)
+
+	var lastErr error
+	for attempt := 1; attempt <= maxRetries; attempt++ {
+		port, err := serial.OpenPort(serialConfig)
+		if err == nil {
+			log.Infof("%s: dispenser opened on %s (attempt %d/%d)", funcName, SerialPort, attempt, maxRetries)
+			return port, nil
+		}
+
+		lastErr = err
+		log.Warnf("%s: failed to open dispenser on %s (attempt %d/%d): %v", funcName, SerialPort, attempt, maxRetries, err)
+		if attempt < maxRetries {
+			time.Sleep(retryDelay)
+		}
 	}
-	return port, nil
+
+	return nil, fmt.Errorf("%s: failed to open dispenser on %s after %d attempts: %w", funcName, SerialPort, maxRetries, lastErr)
 }
 
-func DispenserSequence(port *serial.Port) (string, error) {
-	const funcName = "dispenserSequence"
-	var result string
+// --------------------
+// Internal (port-owner only) operations
+// --------------------
 
-	// Check dispenser status
-	status, err := CheckDispenserStatus(port)
-	if err != nil {
-		return status, fmt.Errorf("[%s] error checking dispenser status: %v", funcName, err)
-	}
-	result += status
-
-	// Send card to encoder position
-	status, err = CardToEncoderPosition(port)
-	if err != nil {
-		return status, fmt.Errorf("[%s] error sending card to encoder position: %v", funcName, err)
-	}
-	result += "; " + status
-
-	return result, nil
-}
-
-// if dispenser is not responding, I should repeat the command
-func CheckDispenserStatus(port *serial.Port) (string, error) {
-	const funcName = "checkDispenserStatus"
-	var result string
+// checkDispenserStatus talks to the device and returns the 4 status bytes [pos0..pos3].
+func checkDispenserStatus(port *serial.Port) ([]byte, error) {
 	checkCmd := buildCheckAP(Address)
 	enq := append([]byte{ENQ}, Address...)
 
-	// Send check command (AP)
 	statusResp, err := sendAndReceive(port, checkCmd, delay)
 	if err != nil {
-		return "", fmt.Errorf("error sending check command: %v", err)
+		return nil, fmt.Errorf("error sending check command: %w", err)
 	}
 	if len(statusResp) == 0 {
-		return "", fmt.Errorf("no response from dispenser")
+		return nil, fmt.Errorf("no response from dispenser")
 	}
-	status, err := checkStatus(statusResp)
-	if err != nil {
-		return status, err
+	if err := checkACK(statusResp); err != nil {
+		return nil, err
 	}
-	result += "; " + status
 
-	// Send ENQ+ADDR to prompt device to execute the command.
 	statusResp, err = sendAndReceive(port, enq, delay)
 	if err != nil {
-		log.Errorf("error sending ENQ: %v", err)
+		return nil, fmt.Errorf("error sending ENQ: %w", err)
 	}
-	if len(statusResp) == 0 {
-		return "", fmt.Errorf("no response from dispenser")
+	if len(statusResp) < 13 {
+		return nil, fmt.Errorf("incomplete status response from dispenser: % X", statusResp)
 	}
-	status, err = checkStatus(statusResp)
-	if err != nil {
-		return status, err
-	}
-	result += status
-	return result, nil
+	return statusResp[7:11], nil
 }
 
-func CardToEncoderPosition(port *serial.Port) (string, error) {
-	const funcName = "cartToEncoderPosition"
+func cardToEncoderPosition(port *serial.Port) error {
 	enq := append([]byte{ENQ}, Address...)
 
-	//Send Dispense card to encoder position (FC7) ---
 	dispenseCmd := createPacket(Address, commandFC7)
 	log.Println("Send card to encoder position")
+
 	statusResp, err := sendAndReceive(port, dispenseCmd, delay)
 	if err != nil {
-		return "", fmt.Errorf("error sending card to encoder position: %v", err)
+		return fmt.Errorf("error sending card to encoder position: %w", err)
 	}
-	_, err = checkStatus(statusResp)
-	if err != nil {
-		return "", err
+	if err := checkACK(statusResp); err != nil {
+		return err
 	}
 
-	//Send ENQ to prompt device ---
 	_, err = port.Write(enq)
 	if err != nil {
-		return "", fmt.Errorf("error sending ENQ to prompt device: %v", err)
+		return fmt.Errorf("error sending ENQ to prompt device: %w", err)
 	}
-
-	time.Sleep(delay)
-
-	//Check card position status
-	status, err := CheckDispenserStatus(port)
-	if err != nil {
-		return "", err
-	}
-	return status, nil
+	return nil
 }
 
-func CardOutOfMouth(port *serial.Port) (string, error) {
-	const funcName = "CardOutOfMouth"
+func cardOutOfMouth(port *serial.Port) error {
 	enq := append([]byte{ENQ}, Address...)
 
-	// Send  card out of card mouth (FC0) ---
 	dispenseCmd := createPacket(Address, commandFC0)
 	log.Println("Send card to out mouth position")
+
 	statusResp, err := sendAndReceive(port, dispenseCmd, delay)
 	if err != nil {
-		return "", fmt.Errorf("error sending out of mouth command: %v", err)
+		return fmt.Errorf("error sending out of mouth command: %w", err)
 	}
-	_, err = checkStatus(statusResp)
-	if err != nil {
-		return "", err
+	if err := checkACK(statusResp); err != nil {
+		return err
 	}
 
-	//Send ENQ to prompt device ---
 	_, err = port.Write(enq)
 	if err != nil {
-		return "", fmt.Errorf("error sending ENQ to prompt device: %v", err)
+		return fmt.Errorf("error sending ENQ to prompt device: %w", err)
 	}
-
-	time.Sleep(delay)
-
-	//Check card position status
-	status, err := CheckDispenserStatus(port)
-	if err != nil {
-		return "", err
-	}
-	return status, nil
+	return nil
 }

dispenser/dispenserclient.go

@@ -0,0 +1,370 @@
+// --------------------
+// Queue-based client (single owner of port)
+// --------------------
+package dispenser
+
+import (
+	"context"
+	"fmt"
+	"sync"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+	"github.com/tarm/serial"
+)
+
+type cmdType int
+
+const (
+	cmdStatus cmdType = iota
+	cmdToEncoder
+	cmdOutOfMouth
+)
+
+type cmdReq struct {
+	typ    cmdType
+	ctx    context.Context
+	respCh chan cmdResp
+}
+
+type cmdResp struct {
+	status []byte
+	err    error
+}
+
+type Client struct {
+	port *serial.Port
+
+	reqCh chan cmdReq
+	done  chan struct{}
+
+	// status cache
+	mu          sync.RWMutex
+	lastStatus  []byte
+	lastStatusT time.Time
+	statusTTL   time.Duration
+
+	// published "stock/cardwell" cache + callback
+	lastStockMu sync.RWMutex
+	lastStock   string
+	onStock     func(string)
+}
+
+// NewClient starts the worker that owns the serial port.
+func NewClient(port *serial.Port, queueSize int) *Client {
+	if queueSize <= 0 {
+		queueSize = 16
+	}
+	c := &Client{
+		port:      port,
+		reqCh:     make(chan cmdReq, queueSize),
+		done:      make(chan struct{}),
+		statusTTL: defaultStatusTTL,
+	}
+	go c.loop()
+	return c
+}
+
+func (c *Client) Close() {
+	select {
+	case <-c.done:
+		return
+	default:
+		close(c.done)
+	}
+}
+
+// Optional: tune cache TTL (how "fresh" cached status must be)
+func (c *Client) SetStatusTTL(d time.Duration) {
+	c.mu.Lock()
+	c.statusTTL = d
+	c.mu.Unlock()
+}
+
+// OnStockUpdate registers a callback called whenever polling (or status reads) produce a stock status string.
+func (c *Client) OnStockUpdate(fn func(string)) {
+	c.lastStockMu.Lock()
+	c.onStock = fn
+	c.lastStockMu.Unlock()
+}
+
+// LastStock returns the most recently computed stock/card-well status string.
+func (c *Client) LastStock() string {
+	c.lastStockMu.RLock()
+	defer c.lastStockMu.RUnlock()
+	return c.lastStock
+}
+
+func (c *Client) setStock(statusBytes []byte) {
+	stock := stockTake(statusBytes)
+
+	c.lastStockMu.Lock()
+	c.lastStock = stock
+	fn := c.onStock
+	c.lastStockMu.Unlock()
+
+	// call outside lock
+	if fn != nil {
+		fn(stock)
+	}
+}
+
+// StartPolling performs a periodic status refresh.
+// It will NOT interrupt commands: it enqueues only when queue is idle.
+func (c *Client) StartPolling(interval time.Duration) {
+	if interval <= 0 {
+		return
+	}
+	go func() {
+		t := time.NewTicker(interval)
+		defer t.Stop()
+
+		for {
+			select {
+			case <-c.done:
+				return
+			case <-t.C:
+				// enqueue only if idle to avoid delaying real commands
+				if len(c.reqCh) != 0 {
+					continue
+				}
+				ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+				_, err := c.CheckStatus(ctx)
+				if err != nil {
+					log.Debugf("dispenser polling: %v", err)
+				}
+				cancel()
+			}
+		}
+	}()
+}
+
+func (c *Client) loop() {
+	for {
+		select {
+		case <-c.done:
+			return
+		case req := <-c.reqCh:
+			c.handle(req)
+		}
+	}
+}
+
+func (c *Client) handle(req cmdReq) {
+	select {
+	case <-req.ctx.Done():
+		req.respCh <- cmdResp{err: req.ctx.Err()}
+		return
+	default:
+	}
+
+	switch req.typ {
+	case cmdStatus:
+		st, err := checkDispenserStatus(c.port)
+		if err == nil && len(st) == 4 {
+			c.mu.Lock()
+			c.lastStatus = append([]byte(nil), st...)
+			c.lastStatusT = time.Now()
+			c.mu.Unlock()
+
+			// publish stock/cardwell
+			c.setStock(st)
+		}
+		req.respCh <- cmdResp{status: st, err: err}
+
+	case cmdToEncoder:
+		err := cardToEncoderPosition(c.port)
+		req.respCh <- cmdResp{err: err}
+
+	case cmdOutOfMouth:
+		err := cardOutOfMouth(c.port)
+		req.respCh <- cmdResp{err: err}
+
+	default:
+		req.respCh <- cmdResp{err: fmt.Errorf("unknown command")}
+	}
+}
+
+func (c *Client) do(ctx context.Context, typ cmdType) ([]byte, error) {
+	rch := make(chan cmdResp, 1)
+	req := cmdReq{typ: typ, ctx: ctx, respCh: rch}
+
+	select {
+	case c.reqCh <- req:
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	}
+
+	select {
+	case r := <-rch:
+		return r.status, r.err
+	case <-ctx.Done():
+		return nil, ctx.Err()
+	}
+}
+
+// CheckStatus returns cached status if fresh, otherwise enqueues a device status read.
+func (c *Client) CheckStatus(ctx context.Context) ([]byte, error) {
+	c.mu.RLock()
+	ttl := c.statusTTL
+	st := append([]byte(nil), c.lastStatus...)
+	ts := c.lastStatusT
+	c.mu.RUnlock()
+
+	if len(st) == 4 && time.Since(ts) <= ttl {
+		// even when returning cached, keep stock in sync
+		c.setStock(st)
+		return st, nil
+	}
+	return c.do(ctx, cmdStatus)
+}
+
+func (c *Client) ToEncoder(ctx context.Context) error {
+	_, err := c.do(ctx, cmdToEncoder)
+	return err
+}
+
+func (c *Client) OutOfMouth(ctx context.Context) error {
+	_, err := c.do(ctx, cmdOutOfMouth)
+	return err
+}
+
+// --------------------
+// Public sequences updated to use Client (queue)
+// --------------------
+
+// DispenserPrepare: check status; if empty => ok; else ensure at encoder.
+func (c *Client) DispenserPrepare(ctx context.Context) (string, error) {
+	const funcName = "DispenserPrepare"
+	stockStatus := ""
+
+	status, err := c.CheckStatus(ctx)
+	if err != nil {
+		return stockStatus, fmt.Errorf("[%s] check status: %w", funcName, err)
+	}
+
+	logStatus(status)
+	stockStatus = stockTake(status)
+	c.setStock(status)
+
+	if isCardWellEmpty(status) {
+		return stockStatus, nil
+	}
+	if isAtEncoderPosition(status) {
+		return stockStatus, nil
+	}
+
+	if err := c.ToEncoder(ctx); err != nil {
+		return stockStatus, fmt.Errorf("[%s] to encoder: %w", funcName, err)
+	}
+
+	time.Sleep(delay)
+	status, err = c.CheckStatus(ctx)
+	if err != nil {
+		return stockStatus, fmt.Errorf("[%s] re-check status: %w", funcName, err)
+	}
+	logStatus(status)
+	stockStatus = stockTake(status)
+	c.setStock(status)
+
+	return stockStatus, nil
+}
+
+func (c *Client) DispenserStart(ctx context.Context) (string, error) {
+	const funcName = "DispenserStart"
+	stockStatus := ""
+
+	status, err := c.CheckStatus(ctx)
+	if err != nil {
+		return stockStatus, fmt.Errorf("[%s] check status: %w", funcName, err)
+	}
+
+	defer func() {
+		logStatus(status)
+	}()
+	stockStatus = stockTake(status)
+	c.setStock(status)
+
+	if isCardWellEmpty(status) {
+		return stockStatus, fmt.Errorf(stockStatus)
+	}
+	if isAtEncoderPosition(status) {
+		return stockStatus, nil
+	}
+
+	if err := c.ToEncoder(ctx); err != nil {
+		return stockStatus, fmt.Errorf("[%s] to encoder: %w", funcName, err)
+	}
+
+	deadline := time.Now().Add(6 * time.Second)
+
+	for {
+		time.Sleep(delay * 2)
+		if time.Now().After(deadline) {
+			return stockStatus, nil
+		}
+
+		status, _ = c.do(ctx, cmdStatus)
+
+		stockStatus = stockTake(status)
+		c.setStock(status)
+		logStatus(status)
+
+		// error states first
+		if isCardWellEmpty(status) {
+			return stockStatus, fmt.Errorf(stockStatus)
+		}
+
+		if isAtEncoderPosition(status) {
+			return stockStatus, nil
+		}
+	}
+}
+
+func (c *Client) DispenserFinal(ctx context.Context) (string, error) {
+	const funcName = "DispenserFinal"
+	stockStatus := ""
+	var status []byte
+
+	if err := c.OutOfMouth(ctx); err != nil {
+		return stockStatus, fmt.Errorf("[%s] out of mouth: %w", funcName, err)
+	}
+
+	time.Sleep(delay)
+	status, err := c.do(ctx, cmdStatus)
+	if err == nil && len(status) >= 4 {
+		c.setStock(status)
+	}
+
+	time.Sleep(delay)
+	if err := c.ToEncoder(ctx); err != nil {
+		return stockStatus, fmt.Errorf("[%s] to encoder: %w", funcName, err)
+	}
+
+	defer func() {
+		logStatus(status)
+	}()
+
+	deadline := time.Now().Add(6 * time.Second)
+
+	for {
+		time.Sleep(delay * 2)
+		if time.Now().After(deadline) {
+			return stockStatus, nil
+		}
+
+		status, _ = c.do(ctx, cmdStatus)
+
+		stockStatus = stockTake(status)
+		c.setStock(status)
+		logStatus(status)
+
+		if isCardWellEmpty(status) {
+			return stockStatus, nil
+		}
+
+		if isAtEncoderPosition(status) {
+			return stockStatus, nil
+		}
+	}
+}

errorhandlers/errorhandlers.go

@@ -0,0 +1,30 @@
+package errorhandlers
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+
+	"gitea.futuresens.co.uk/futuresens/cmstypes"
+	log "github.com/sirupsen/logrus"
+)
+
+// writeError is a helper to send a JSON error and HTTP status in one go.
+func WriteError(w http.ResponseWriter, status int, msg string) {
+	theResponse := cmstypes.StatusRec{
+		Code:    status,
+		Message: msg,
+	}
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(status)
+	json.NewEncoder(w).Encode(theResponse)
+}
+
+func FatalError(err error) {
+	fmt.Println(err.Error())
+	log.Errorf(err.Error())
+	fmt.Println(". Press Enter to exit...")
+	fmt.Scanln()
+	os.Exit(1)
+}

go.mod

@@ -7,6 +7,7 @@ require (
 	gitea.futuresens.co.uk/futuresens/logging v1.0.9
 	github.com/alexbrainman/printer v0.0.0-20200912035444-f40f26f0bdeb
 	github.com/denisenkom/go-mssqldb v0.12.3
+	github.com/mailjet/mailjet-apiv3-go v0.0.0-20201009050126-c24bc15a9394
 	github.com/sirupsen/logrus v1.9.3
 	github.com/tarm/serial v0.0.0-20180830185346-98f6abe2eb07
 	golang.org/x/image v0.27.0

go.sum

@@ -19,6 +19,8 @@ github.com/golang-sql/civil v0.0.0-20190719163853-cb61b32ac6fe h1:lXe2qZdvpiX5WZ
 github.com/golang-sql/civil v0.0.0-20190719163853-cb61b32ac6fe/go.mod h1:8vg3r2VgvsThLBIFL93Qb5yWzgyZWhEmBwUJWevAkK0=
 github.com/golang-sql/sqlexp v0.1.0 h1:ZCD6MBpcuOVfGVqsEmY5/4FtYiKz6tSyUv9LPEDei6A=
 github.com/golang-sql/sqlexp v0.1.0/go.mod h1:J4ad9Vo8ZCWQ2GMrC4UCQy1JpCbwU9m3EOqtpKwwwHI=
+github.com/mailjet/mailjet-apiv3-go v0.0.0-20201009050126-c24bc15a9394 h1:+6kiV40vfmh17TDlZG15C2uGje1/XBGT32j6xKmUkqM=
+github.com/mailjet/mailjet-apiv3-go v0.0.0-20201009050126-c24bc15a9394/go.mod h1:ogN8Sxy3n5VKLhQxbtSBM3ICG/VgjXS/akQJIoDSrgA=
 github.com/modocache/gover v0.0.0-20171022184752-b58185e213c5/go.mod h1:caMODM3PzxT8aQXRPkAt8xlV/e7d7w8GM5g0fa5F0D8=
 github.com/pkg/browser v0.0.0-20180916011732-0a3d74bf9ce4/go.mod h1:4OwLy04Bl9Ef3GJJCoec+30X3LQs/0/m4HFRt/2LUSA=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=

handlers/db_helpers.go

@@ -0,0 +1,206 @@
+package handlers
+
+import (
+	"bufio"
+	"context"
+	"database/sql"
+	"encoding/json"
+	"fmt"
+	"os"
+	"path/filepath"
+	"time"
+
+	"gitea.futuresens.co.uk/futuresens/hardlink/db"
+	log "github.com/sirupsen/logrus"
+)
+
+type preauthSpoolRecord struct {
+	CreatedAt    time.Time         `json:"createdAt"`
+	CheckoutDate string            `json:"checkoutDate"` // keep as received
+	Fields       map[string]string `json:"fields"`       // ChipDNA result.Fields
+}
+
+func (app *App) getDB(ctx context.Context) (*sql.DB, error) {
+	app.dbMu.Lock()
+	defer app.dbMu.Unlock()
+
+	// Fast path: db exists and is alive
+	if app.db != nil {
+		pingCtx, cancel := context.WithTimeout(ctx, 1*time.Second)
+		defer cancel()
+
+		if err := app.db.PingContext(pingCtx); err == nil {
+			return app.db, nil
+		}
+
+		// stale handle
+		_ = app.db.Close()
+		app.db = nil
+	}
+
+	// Reconnect once, bounded
+	dialCtx, cancel := context.WithTimeout(ctx, 3*time.Second)
+	defer cancel()
+
+	dbConn, err := db.InitMSSQL(
+		app.cfg.Dbport,
+		app.cfg.Dbuser,
+		app.cfg.Dbpassword,
+		app.cfg.Dbname,
+	)
+	if err != nil {
+		return nil, err
+	}
+
+	pingCtx, cancel2 := context.WithTimeout(dialCtx, 1*time.Second)
+	defer cancel2()
+
+	if err := dbConn.PingContext(pingCtx); err != nil {
+		_ = dbConn.Close()
+		return nil, err
+	}
+
+	app.db = dbConn
+	return app.db, nil
+}
+
+func (app *App) spoolPath() string {
+	// keep it near logs; adjust if you prefer a dedicated dir
+	// ensure LogDir ends with separator in your config loader
+	return filepath.Join(app.cfg.LogDir, "preauth_spool.ndjson")
+}
+
+// persistPreauth tries DB first; if DB is down or insert fails, it spools to file.
+// It never returns an error to the caller (so your HTTP flow stays simple),
+// but it logs failures.
+func (app *App) persistPreauth(ctx context.Context, fields map[string]string, checkoutDate string) {
+	// First, try DB (with your reconnect logic inside getDB)
+	dbConn, err := app.getDB(ctx)
+	if err == nil && dbConn != nil {
+		if err := db.InsertPreauth(ctx, dbConn, fields, checkoutDate); err == nil {
+			// opportunistic drain once DB is alive
+			go app.drainPreauthSpool(context.Background())
+			return
+		} else {
+			log.WithError(err).Warn("DB insert failed; will spool preauth")
+		}
+	} else {
+		log.WithError(err).Warn("DB unavailable; will spool preauth")
+	}
+
+	// Fallback: spool to file
+	rec := preauthSpoolRecord{
+		CreatedAt:    time.Now().UTC(),
+		CheckoutDate: checkoutDate,
+		Fields:       fields,
+	}
+	if spErr := app.spoolPreauth(rec); spErr != nil {
+		log.WithError(spErr).Error("failed to spool preauth")
+	}
+}
+
+// append one line JSON (NDJSON)
+func (app *App) spoolPreauth(rec preauthSpoolRecord) error {
+	p := app.spoolPath()
+
+	f, err := os.OpenFile(p, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0666)
+	if err != nil {
+		return fmt.Errorf("open spool file: %w", err)
+	}
+	defer f.Close()
+
+	b, err := json.Marshal(rec)
+	if err != nil {
+		return fmt.Errorf("marshal spool record: %w", err)
+	}
+
+	if _, err := f.Write(append(b, '\n')); err != nil {
+		return fmt.Errorf("write spool record: %w", err)
+	}
+
+	return f.Sync() // ensure it's on disk
+}
+
+// Drain spool into DB.
+// Strategy: read all lines, insert each; keep failures in a temp file; then replace original.
+func (app *App) drainPreauthSpool(ctx context.Context) {
+	dbConn, err := app.getDB(ctx)
+	if err != nil {
+		return // still down, nothing to do
+	}
+
+	spool := app.spoolPath()
+	in, err := os.Open(spool)
+	if err != nil {
+		// no spool is fine
+		return
+	}
+	defer in.Close()
+
+	tmp := spool + ".tmp"
+	out, err := os.OpenFile(tmp, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, 0666)
+	if err != nil {
+		log.WithError(err).Warn("drain spool: open tmp failed")
+		return
+	}
+	defer out.Close()
+
+	sc := bufio.NewScanner(in)
+	// allow long lines if receipts ever sneak in (shouldn't, but safe)
+	buf := make([]byte, 0, 64*1024)
+	sc.Buffer(buf, 2*1024*1024)
+
+	var (
+		okCount   int
+		failCount int
+	)
+
+	for sc.Scan() {
+		line := sc.Bytes()
+		if len(line) == 0 {
+			continue
+		}
+
+		var rec preauthSpoolRecord
+		if err := json.Unmarshal(line, &rec); err != nil {
+			// malformed line: keep it so we don't lose evidence
+			_, _ = out.Write(append(line, '\n'))
+			failCount++
+			continue
+		}
+
+		// attempt insert
+		if err := db.InsertPreauth(ctx, dbConn, rec.Fields, rec.CheckoutDate); err != nil {
+			// DB still flaky or data issue: keep it for later retry
+			_, _ = out.Write(append(line, '\n'))
+			failCount++
+			continue
+		}
+
+		okCount++
+	}
+
+	if err := sc.Err(); err != nil {
+		log.WithError(err).Warn("drain spool: scanner error")
+		// best effort; do not replace spool
+		return
+	}
+
+	_ = out.Sync()
+
+	// Replace original spool with temp (atomic on Windows is best-effort; still OK here)
+	_ = in.Close()
+	_ = out.Close()
+
+	if err := os.Rename(tmp, spool); err != nil {
+		log.WithError(err).Warn("drain spool: rename failed")
+		return
+	}
+
+	if okCount > 0 || failCount > 0 {
+		log.WithFields(log.Fields{
+			"inserted":  okCount,
+			"remaining": failCount,
+		}).Info("preauth spool drained")
+	}
+}

handlers/handlers.go

@@ -1,21 +1,22 @@
 package handlers
 
 import (
-	"bytes"
+	"context"
 	"database/sql"
 	"encoding/json"
 	"encoding/xml"
 	"io"
 	"net/http"
 	"strings"
+	"sync"
 	"time"
 
-	"github.com/tarm/serial"
-
 	"gitea.futuresens.co.uk/futuresens/cmstypes"
-	"gitea.futuresens.co.uk/futuresens/hardlink/db"
+	"gitea.futuresens.co.uk/futuresens/hardlink/config"
 	"gitea.futuresens.co.uk/futuresens/hardlink/dispenser"
+	"gitea.futuresens.co.uk/futuresens/hardlink/errorhandlers"
 	"gitea.futuresens.co.uk/futuresens/hardlink/lockserver"
+	"gitea.futuresens.co.uk/futuresens/hardlink/mail"
 	"gitea.futuresens.co.uk/futuresens/hardlink/payment"
 	"gitea.futuresens.co.uk/futuresens/hardlink/printer"
 	"gitea.futuresens.co.uk/futuresens/hardlink/types"
@@ -24,19 +25,29 @@ import (
 )
 
 type App struct {
-	dispPort   *serial.Port
-	lockserver lockserver.LockServer
-	isPayment  bool
-	db         *sql.DB
+	disp               *dispenser.Client
+	lockserver         lockserver.LockServer
+	isPayment          bool
+	db                 *sql.DB
+	cfg                *config.ConfigRec
+	dbMu               sync.Mutex
+	cardWellMu         sync.RWMutex
+	cardWellStatus     string
+	availabilityMu     sync.Mutex
+	availabilityTimers map[string]*time.Timer
 }
 
-func NewApp(dispPort *serial.Port, lockType, encoderAddress string, db *sql.DB, isPayment bool) *App {
-	return &App{
-		isPayment:  isPayment,
-		dispPort:   dispPort,
-		lockserver: lockserver.NewLockServer(lockType, encoderAddress, FatalError),
-		db:         db,
+func NewApp(disp *dispenser.Client, lockType, encoderAddress, cardWellStatus string, db *sql.DB, cfg *config.ConfigRec) *App {
+	app := &App{
+		isPayment:          cfg.IsPayment,
+		disp:               disp,
+		lockserver:         lockserver.NewLockServer(lockType, encoderAddress, errorhandlers.FatalError),
+		db:                 db,
+		cfg:                cfg,
+		availabilityTimers: make(map[string]*time.Timer),
 	}
+	app.SetCardWellStatus(cardWellStatus)
+	return app
 }
 
 func (app *App) RegisterRoutes(mux *http.ServeMux) {
@@ -44,10 +55,15 @@ func (app *App) RegisterRoutes(mux *http.ServeMux) {
 	mux.HandleFunc("/printroomticket", app.printRoomTicket)
 	mux.HandleFunc("/takepreauth", app.takePreauthorization)
 	mux.HandleFunc("/takepayment", app.takePayment)
+	mux.HandleFunc("/dispenserstatus", app.reportDispenserStatus)
+	mux.HandleFunc("/testissuedoorcard", app.testIssueDoorCard)
+	mux.HandleFunc("/ping-pdq", app.fetchChipDNAStatus)
+	mux.HandleFunc("/logerror", app.onChipDNAError)
 }
 
 func (app *App) takePreauthorization(w http.ResponseWriter, r *http.Request) {
 	const op = logging.Op("takePreauthorization")
+
 	var (
 		theResponse cmstypes.ResponseRec
 		theRequest  cmstypes.TransactionRec
@@ -65,9 +81,12 @@ func (app *App) takePreauthorization(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 
 	if !app.isPayment {
-		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Payment processing is disabled")
-		writeTransactionResult(w, http.StatusServiceUnavailable, theResponse)
-		return
+		if !app.cfg.TestMode {
+			mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, "Payment Error", "Attempted preauthorization while payment processing is disabled")
+			theResponse.Data = payment.BuildFailureURL(types.ResultError, "Payment processing is disabled")
+			writeTransactionResult(w, http.StatusServiceUnavailable, theResponse)
+			return
+		}
 	}
 
 	if r.Method == http.MethodOptions {
@@ -81,63 +100,74 @@ func (app *App) takePreauthorization(w http.ResponseWriter, r *http.Request) {
 		writeTransactionResult(w, http.StatusMethodNotAllowed, theResponse)
 		return
 	}
-	defer r.Body.Close()
 
-	if ct := r.Header.Get("Content-Type"); ct != "text/xml" {
+	if r.Header.Get("Content-Type") != "text/xml" {
 		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Content-Type must be text/xml")
 		writeTransactionResult(w, http.StatusUnsupportedMediaType, theResponse)
 		return
 	}
 
-	body, _ := io.ReadAll(r.Body)
-	err := xml.Unmarshal(body, &theRequest)
+	defer r.Body.Close()
+
+	body, err := io.ReadAll(r.Body)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "ReadXML", string(op), "", "", 0)
+		logging.Error(types.ServiceName, err.Error(), "Read body error", string(op), "", "", 0)
+		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Failed to read request body")
+		writeTransactionResult(w, http.StatusBadRequest, theResponse)
+		return
+	}
+
+	if err := xml.Unmarshal(body, &theRequest); err != nil {
+		logging.Error(types.ServiceName, err.Error(), "ReadXML", string(op), "", "", 0)
 		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Invalid XML payload")
 		writeTransactionResult(w, http.StatusBadRequest, theResponse)
 		return
 	}
-	log.Printf("Transaction payload: Amount=%s, Type=%s", theRequest.AmountMinorUnits, theRequest.TransactionType)
+
+	log.Printf(
+		"Preauthorization payload: Amount=%s, Type=%s",
+		theRequest.AmountMinorUnits,
+		theRequest.TransactionType,
+	)
 
 	client := &http.Client{Timeout: 300 * time.Second}
-	response, err := client.Post(types.LinkTakePreauthorization, "text/xml", bytes.NewBuffer(body))
+
+	// ---- START TRANSACTION ----
+
+	body, err = callChipDNA(client, types.LinkStartTransaction, body)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "Payment processing error", string(op), "", "", 0)
+		logging.Error(types.ServiceName, err.Error(), "Preauth processing error", string(op), "", "", 0)
+
 		theResponse.Data = payment.BuildFailureURL(types.ResultError, "No response from payment processor")
 		writeTransactionResult(w, http.StatusBadGateway, theResponse)
 		return
 	}
-	defer response.Body.Close()
-
-	body, err = io.ReadAll(response.Body)
-	if err != nil {
-		logging.Error(serviceName, err.Error(), "Read response body error", string(op), "", "", 0)
-		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Failed to read response body")
-		writeTransactionResult(w, http.StatusInternalServerError, theResponse)
-		return
-	}
 
 	if err := trResult.ParseTransactionResult(body); err != nil {
-		logging.Error(serviceName, err.Error(), "Parse transaction result error", string(op), "", "", 0)
+		logging.Error(types.ServiceName, err.Error(), "Parse transaction result error", string(op), "", "", 0)
 	}
 
-	// Compose JSON from responseEntries
 	result.FillFromTransactionResult(trResult)
 
-	if err := printer.PrintCardholderReceipt(result.CardholderReceipt); err != nil {
-		log.Errorf("PrintCardholderReceipt error: %v", err)
-	}
+	// ---- PRINT RECEIPT ----
+
+	printer.PrintReceipt(result.CardholderReceipt)
+
+	// ---- REDIRECT ----
 
 	theResponse.Status = result.Status
 	theResponse.Data, save = payment.BuildPreauthRedirectURL(result.Fields)
+
 	if save {
-		db.InsertPreauth(r.Context(), app.db, result.Fields, theRequest.CheckoutDate)
+		go app.persistPreauth(context.Background(), result.Fields, theRequest.CheckoutDate)
 	}
+
 	writeTransactionResult(w, http.StatusOK, theResponse)
 }
 
 func (app *App) takePayment(w http.ResponseWriter, r *http.Request) {
 	const op = logging.Op("takePayment")
+
 	var (
 		theResponse cmstypes.ResponseRec
 		theRequest  cmstypes.TransactionRec
@@ -154,9 +184,14 @@ func (app *App) takePayment(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 
 	if !app.isPayment {
-		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Payment processing is disabled")
-		writeTransactionResult(w, http.StatusServiceUnavailable, theResponse)
-		return
+		if !app.cfg.TestMode {
+			mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, "Payment Error", "Attempted payment while payment processing is disabled")
+			theResponse.Status.Code = http.StatusServiceUnavailable
+			theResponse.Data = payment.BuildFailureURL(types.ResultError, "Payment processing is disabled")
+			writeTransactionResult(w, http.StatusServiceUnavailable, theResponse)
+			return
+		}
+		
 	}
 
 	if r.Method == http.MethodOptions {
@@ -170,55 +205,118 @@ func (app *App) takePayment(w http.ResponseWriter, r *http.Request) {
 		writeTransactionResult(w, http.StatusMethodNotAllowed, theResponse)
 		return
 	}
-	defer r.Body.Close()
 
-	if ct := r.Header.Get("Content-Type"); ct != "text/xml" {
+	if r.Header.Get("Content-Type") != "text/xml" {
 		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Content-Type must be text/xml")
 		writeTransactionResult(w, http.StatusUnsupportedMediaType, theResponse)
 		return
 	}
 
-	body, _ := io.ReadAll(r.Body)
-	err := xml.Unmarshal(body, &theRequest)
+	defer r.Body.Close()
+
+	body, err := io.ReadAll(r.Body)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "ReadXML", string(op), "", "", 0)
+		logging.Error(types.ServiceName, err.Error(), "Read body error", string(op), "", "", 0)
+		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Failed to read request body")
+		writeTransactionResult(w, http.StatusBadRequest, theResponse)
+		return
+	}
+
+	if err := xml.Unmarshal(body, &theRequest); err != nil {
+		logging.Error(types.ServiceName, err.Error(), "ReadXML", string(op), "", "", 0)
 		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Invalid XML payload")
 		writeTransactionResult(w, http.StatusBadRequest, theResponse)
 		return
 	}
-	log.Printf("Transaction payload: Amount=%s, Type=%s", theRequest.AmountMinorUnits, theRequest.TransactionType)
+
+	log.Printf("Transaction payload: Amount=%s, Type=%s",
+		theRequest.AmountMinorUnits,
+		theRequest.TransactionType,
+	)
 
 	client := &http.Client{Timeout: 300 * time.Second}
-	response, err := client.Post(types.LinkTakePayment, "text/xml", bytes.NewBuffer(body))
+
+	// ---- START TRANSACTION ----
+
+	body, err = callChipDNA(client, types.LinkStartTransaction, body)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "Payment processing error", string(op), "", "", 0)
+		logging.Error(types.ServiceName, err.Error(), "Start transaction error", string(op), "", "", 0)
+
 		theResponse.Data = payment.BuildFailureURL(types.ResultError, "No response from payment processor")
 		writeTransactionResult(w, http.StatusBadGateway, theResponse)
 		return
 	}
-	defer response.Body.Close()
 
-	body, err = io.ReadAll(response.Body)
+	if err := trResult.ParseTransactionResult(body); err != nil {
+		logging.Error(types.ServiceName, err.Error(), "Parse transaction result error", string(op), "", "", 0)
+	}
+
+	result.FillFromTransactionResult(trResult)
+
+	res := result.Fields[types.TransactionResult]
+
+	if !strings.EqualFold(res, types.ResultApproved) {
+		printer.PrintReceipt(result.CardholderReceipt)
+		desc := result.Fields[types.ErrorDescription]
+		if desc == "" {
+			desc = result.Fields[types.Errors]
+		}
+		logging.Error(types.ServiceName, "Preauthorization failed", "Result: "+res+" Description: "+desc, string(op), "", app.cfg.Hotel, app.cfg.Kiosk)
+		theResponse.Status = result.Status
+		theResponse.Data = payment.BuildFailureURL(res, result.Fields[types.Errors])
+
+		writeTransactionResult(w, http.StatusOK, theResponse)
+		return
+	}
+
+	// ---- CONFIRM TRANSACTION ----
+
+	ref := result.Fields[types.Reference]
+	log.Printf("Preauth approved, reference: %s. Sending confirm...", ref)
+	confirmReq := payment.ConfirmTransactionRequest{
+		Amount:    theRequest.AmountMinorUnits,
+		Reference: ref,
+	}
+
+	body, err = confirmWithRetry(client, confirmReq, 2)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "Read response body error", string(op), "", "", 0)
-		theResponse.Data = payment.BuildFailureURL(types.ResultError, "Failed to read response body")
-		writeTransactionResult(w, http.StatusInternalServerError, theResponse)
+		logging.Error(types.ServiceName, err.Error(), "Confirm transaction error", string(op), "", "", 0)
+		mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, "Payment confirmation failed", "Reference: "+ref+", Error: "+err.Error())
+		theResponse.Data = payment.BuildFailureURL(types.ResultError, "ConfirmTransactionError")
+		writeTransactionResult(w, http.StatusBadGateway, theResponse)
 		return
 	}
 
 	if err := trResult.ParseTransactionResult(body); err != nil {
-		logging.Error(serviceName, err.Error(), "Parse transaction result error", string(op), "", "", 0)
+		logging.Error(types.ServiceName, err.Error(), "Parse confirm result error", string(op), "", "", 0)
 	}
 
-	// Compose JSON from responseEntries
 	result.FillFromTransactionResult(trResult)
 
-	if err := printer.PrintCardholderReceipt(result.CardholderReceipt); err != nil {
-		log.Errorf("PrintCardholderReceipt error: %v", err)
+	res = result.Fields[types.TransactionResult]
+
+	if !strings.EqualFold(res, types.ResultApproved) {
+		printer.PrintReceipt(result.CardholderReceipt)
+		desc := result.Fields[types.ErrorDescription]
+		if desc == "" {
+			desc = result.Fields[types.Errors]
+		}
+		logging.Error(types.ServiceName, "Transaction not approved after confirm", "Confirm result: "+res+" Description: "+desc, string(op), "", app.cfg.Hotel, app.cfg.Kiosk)
+		mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, "Payment confirmation failed", "Reference: "+ref+", Confirm result: "+res+" Description: "+desc)
+		theResponse.Status = result.Status
+		theResponse.Data = payment.BuildFailureURL(res, result.Fields[types.Errors])
+
+		writeTransactionResult(w, http.StatusOK, theResponse)
+		return
 	}
 
+	// ---- SUCCESS ----
+
+	printer.PrintReceipt(result.CardholderReceipt)
+	log.Printf("Transaction approved and confirmed, reference: %s", ref)
 	theResponse.Status = result.Status
-	theResponse.Data = payment.BuildPaymentRedirectURL(result.Fields)
+	theResponse.Data = payment.BuildSuccessURL(result.Fields)
+
 	writeTransactionResult(w, http.StatusOK, theResponse)
 }
 
@@ -241,92 +339,81 @@ func (app *App) issueDoorCard(w http.ResponseWriter, r *http.Request) {
 
 	log.Println("issueDoorCard called")
 	if r.Method != http.MethodPost {
-		writeError(w, http.StatusMethodNotAllowed, "Method not allowed; use POST")
+		errorhandlers.WriteError(w, http.StatusMethodNotAllowed, "Method not allowed; use POST")
 		return
 	}
 	defer r.Body.Close()
 
 	if ct := r.Header.Get("Content-Type"); ct != "application/json" {
-		writeError(w, http.StatusUnsupportedMediaType, "Content-Type must be application/json")
+		errorhandlers.WriteError(w, http.StatusUnsupportedMediaType, "Content-Type must be application/json")
 		return
 	}
 
 	if err := json.NewDecoder(r.Body).Decode(&doorReq); err != nil {
-		logging.Error(serviceName, err.Error(), "ReadJSON", string(op), "", "", 0)
-		writeError(w, http.StatusBadRequest, "Invalid JSON payload: "+err.Error())
+		logging.Error(types.ServiceName, err.Error(), "ReadJSON", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Invalid JSON payload: "+err.Error())
 		return
 	}
 
 	// parse times
 	checkIn, err := time.Parse(types.CustomLayout, doorReq.CheckinTime)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "Invalid checkinTime format", string(op), "", "", 0)
-		writeError(w, http.StatusBadRequest, "Invalid checkinTime format: "+err.Error())
+		logging.Error(types.ServiceName, err.Error(), "Invalid checkinTime format", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Invalid checkinTime format: "+err.Error())
 		return
 	}
 	checkOut, err := time.Parse(types.CustomLayout, doorReq.CheckoutTime)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "Invalid checkoutTime format", string(op), "", "", 0)
-		writeError(w, http.StatusBadRequest, "Invalid checkoutTime format: "+err.Error())
+		logging.Error(types.ServiceName, err.Error(), "Invalid checkoutTime format", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Invalid checkoutTime format: "+err.Error())
 		return
 	}
 
-	// card to encoder position if not there already
-	if status, err := dispenser.DispenserSequence(app.dispPort); err != nil {
-		if status != "" {
-			logging.Error(serviceName, status, "Dispense error", string(op), "", "", 0)
-			writeError(w, http.StatusServiceUnavailable, "Dispense error: "+err.Error())
-		} else {
-			logging.Error(serviceName, err.Error(), "Dispense error", string(op), "", "", 0)
-			writeError(w, http.StatusServiceUnavailable, "Dispense error: "+err.Error()+"; check card stock")
-		}
+	// Ensure dispenser ready (card at encoder) BEFORE we attempt encoding.
+	// With queued dispenser ops, this will not clash with polling.
+	status, err := app.disp.DispenserStart(r.Context())
+	app.SetCardWellStatus(status)
+	if err != nil {
+		logging.Error(types.ServiceName, err.Error(), "Dispense error", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusServiceUnavailable, "Dispense error: "+err.Error())
 		return
-	} else {
-		log.Info(status)
+	}
+
+	// Always attempt to finalize after we have moved a card / started an issuance flow.
+	// This guarantees we eject and prepare the next card even on lock failures.
+	finalize := func() {
+		if app.disp == nil {
+			return
+		}
+		ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
+		defer cancel()
+
+		status, ferr := app.disp.DispenserFinal(ctx)
+		if ferr != nil {
+			logging.Error(types.ServiceName, ferr.Error(), "Dispenser final error", string(op), "", "", 0)
+			return
+		}
+		app.SetCardWellStatus(status)
 	}
 
 	// build lock server command
 	app.lockserver.BuildCommand(doorReq, checkIn, checkOut)
 
 	// lock server sequence
-	err = app.lockserver.LockSequence()
-	if err != nil {
-		logging.Error(serviceName, err.Error(), "Key encoding", string(op), "", "", 0)
-		writeError(w, http.StatusBadGateway, err.Error())
-		dispenser.CardOutOfMouth(app.dispPort)
-		dispenser.DispenserSequence(app.dispPort)
+	if err := app.lockserver.LockSequence(); err != nil {
+		logging.Error(types.ServiceName, err.Error(), "Key encoding", string(op), "", "", 0)
+		finalize()
+		errorhandlers.WriteError(w, http.StatusBadGateway, err.Error())
 		return
 	}
 
-	// card out of mouth
-	if status, err := dispenser.CardOutOfMouth(app.dispPort); err != nil {
-		logging.Error(serviceName, err.Error(), "Dispenser eject error", string(op), "", "", 0)
-		writeError(w, http.StatusServiceUnavailable, "Dispenser eject error: "+err.Error())
-		return
-	} else {
-		log.Info(status)
-	}
-
-	// card to encoder position
-	if status, err := dispenser.DispenserSequence(app.dispPort); err != nil {
-		if status != "" {
-			logging.Error(serviceName, status, "Dispense error", string(op), "", "", 0)
-			writeError(w, http.StatusServiceUnavailable, "Dispense error: "+err.Error())
-		} else {
-			logging.Error(serviceName, err.Error(), "Dispense error", string(op), "", "", 0)
-			writeError(w, http.StatusServiceUnavailable, "Dispense error: "+err.Error()+"; check card stock")
-		}
-		return
-	} else {
-		log.Info(status)
-	}
+	// final dispenser steps
+	finalize()
 
 	theResponse.Code = http.StatusOK
 	theResponse.Message = "Card issued successfully"
-	// success! return 200 and any data you like
-	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(http.StatusOK)
-	json.NewEncoder(w).Encode(theResponse)
+	_ = json.NewEncoder(w).Encode(theResponse)
 }
 
 func (app *App) printRoomTicket(w http.ResponseWriter, r *http.Request) {
@@ -343,32 +430,32 @@ func (app *App) printRoomTicket(w http.ResponseWriter, r *http.Request) {
 	}
 	log.Println("printRoomTicket called")
 	if r.Method != http.MethodPost {
-		writeError(w, http.StatusMethodNotAllowed, "Method not allowed; use POST")
+		errorhandlers.WriteError(w, http.StatusMethodNotAllowed, "Method not allowed; use POST")
 		return
 	}
 	if ct := r.Header.Get("Content-Type"); !strings.Contains(ct, "xml") {
-		writeError(w, http.StatusUnsupportedMediaType, "Content-Type must be application/xml")
+		errorhandlers.WriteError(w, http.StatusUnsupportedMediaType, "Content-Type must be application/xml")
 		return
 	}
 
 	defer r.Body.Close()
 	if err := xml.NewDecoder(r.Body).Decode(&roomDetails); err != nil {
-		logging.Error(serviceName, err.Error(), "ReadXML", string(op), "", "", 0)
-		writeError(w, http.StatusBadRequest, "Invalid XML payload: "+err.Error())
+		logging.Error(types.ServiceName, err.Error(), "ReadXML", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Invalid XML payload: "+err.Error())
 		return
 	}
 
 	data, err := printer.BuildRoomTicket(roomDetails)
 	if err != nil {
-		logging.Error(serviceName, err.Error(), "BuildRoomTicket", string(op), "", "", 0)
-		writeError(w, http.StatusInternalServerError, "BuildRoomTicket failed: "+err.Error())
+		logging.Error(types.ServiceName, err.Error(), "BuildRoomTicket", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusInternalServerError, "BuildRoomTicket failed: "+err.Error())
 		return
 	}
 
 	// Send to the Windows Epson TM-T82II via the printer package
 	if err := printer.SendToPrinter(data); err != nil {
-		logging.Error(serviceName, err.Error(), "printRoomTicket", "printRoomTicket", "", "", 0)
-		writeError(w, http.StatusInternalServerError, "Print failed: "+err.Error())
+		logging.Error(types.ServiceName, err.Error(), "printRoomTicket", "printRoomTicket", "", "", 0)
+		errorhandlers.WriteError(w, http.StatusInternalServerError, "Print failed: "+err.Error())
 		return
 	}
 
@@ -380,3 +467,29 @@ func (app *App) printRoomTicket(w http.ResponseWriter, r *http.Request) {
 		Message: "Print job sent successfully",
 	})
 }
+
+func (app *App) reportDispenserStatus(w http.ResponseWriter, r *http.Request) {
+	w.Header().Set("Content-Type", "application/json")
+	w.WriteHeader(http.StatusOK)
+	_ = json.NewEncoder(w).Encode(cmstypes.StatusRec{
+		Code:    http.StatusOK,
+		Message: app.CardWellStatus(),
+	})
+}
+
+func (app *App) SetCardWellStatus(s string) {
+	app.cardWellMu.Lock()
+	prev := app.cardWellStatus
+	app.cardWellStatus = s
+	app.cardWellMu.Unlock()
+
+	if s != "" && prev != s {
+		mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, "Dispenser Error Status", "Status: "+s)
+	}
+}
+
+func (app *App) CardWellStatus() string {
+	app.cardWellMu.RLock()
+	defer app.cardWellMu.RUnlock()
+	return app.cardWellStatus
+}

handlers/http_helpers.go

@@ -1,41 +1,71 @@
 package handlers
 
 import (
+	"bytes"
 	"encoding/json"
-	"fmt"
+	"encoding/xml"
+	"io"
 	"net/http"
-	"os"
+	"time"
 
 	"gitea.futuresens.co.uk/futuresens/cmstypes"
+	"gitea.futuresens.co.uk/futuresens/hardlink/payment"
+	"gitea.futuresens.co.uk/futuresens/hardlink/types"
 	"gitea.futuresens.co.uk/futuresens/logging"
 	log "github.com/sirupsen/logrus"
 )
 
-const serviceName = "hardlink"
-
-// writeError is a helper to send a JSON error and HTTP status in one go.
-func writeError(w http.ResponseWriter, status int, msg string) {
-	theResponse := cmstypes.StatusRec{
-		Code:    status,
-		Message: msg,
-	}
-	w.Header().Set("Content-Type", "application/json")
-	w.WriteHeader(status)
-	json.NewEncoder(w).Encode(theResponse)
-}
-
 func writeTransactionResult(w http.ResponseWriter, status int, theResponse cmstypes.ResponseRec) {
 	w.Header().Set("Content-Type", "application/json")
 	w.WriteHeader(status)
 	if err := json.NewEncoder(w).Encode(theResponse); err != nil {
-		logging.Error(serviceName, err.Error(), "JSON encode error", "startTransaction", "", "", 0)
+		logging.Error(types.ServiceName, err.Error(), "JSON encode error", "startTransaction", "", "", 0)
 	}
 }
 
-func FatalError(err error) {
-	fmt.Println(err.Error())
-	log.Errorf(err.Error())
-	fmt.Println(". Press Enter to exit...")
-	fmt.Scanln()
-	os.Exit(1)
+func callChipDNA(client *http.Client, url string, payload []byte) ([]byte, error) {
+
+	resp, err := client.Post(url, "text/xml", bytes.NewBuffer(payload))
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	return io.ReadAll(resp.Body)
+}
+
+func confirmWithRetry(client *http.Client, req payment.ConfirmTransactionRequest, attempts int) ([]byte, error) {
+
+	payload, err := xml.Marshal(req)
+	if err != nil {
+		return nil, err
+	}
+
+	var lastErr error
+
+	for i := 1; i <= attempts; i++ {
+
+		resp, err := client.Post(types.LinkConfirmTransaction, "text/xml", bytes.NewBuffer(payload))
+		if err != nil {
+			lastErr = err
+		} else {
+
+			body, readErr := io.ReadAll(resp.Body)
+			resp.Body.Close()
+
+			if readErr != nil {
+				lastErr = readErr
+			} else {
+				return body, nil
+			}
+		}
+
+		log.Warnf("ConfirmTransaction attempt %d/%d failed: %v", i, attempts, lastErr)
+
+		if i < attempts {
+			time.Sleep(2 * time.Second)
+		}
+	}
+
+	return nil, lastErr
 }

handlers/testhandlers.go

@@ -0,0 +1,252 @@
+package handlers
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+
+	"gitea.futuresens.co.uk/futuresens/cmstypes"
+	"gitea.futuresens.co.uk/futuresens/hardlink/errorhandlers"
+	"gitea.futuresens.co.uk/futuresens/hardlink/lockserver"
+	"gitea.futuresens.co.uk/futuresens/hardlink/mail"
+	"gitea.futuresens.co.uk/futuresens/hardlink/payment"
+	"gitea.futuresens.co.uk/futuresens/hardlink/types"
+	"gitea.futuresens.co.uk/futuresens/logging"
+	log "github.com/sirupsen/logrus"
+)
+
+func (app *App) testIssueDoorCard(w http.ResponseWriter, r *http.Request) {
+	const op = logging.Op("issueDoorCard")
+	var (
+		doorReq     lockserver.DoorCardRequest
+		theResponse cmstypes.StatusRec
+	)
+
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+	w.Header().Set("Access-Control-Allow-Methods", "POST, OPTIONS")
+	w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+	w.Header().Set("Content-Type", "application/json")
+
+	if r.Method == http.MethodOptions {
+		w.WriteHeader(http.StatusNoContent)
+		return
+	}
+
+	log.Println("issueDoorCard called")
+	if r.Method != http.MethodPost {
+		errorhandlers.WriteError(w, http.StatusMethodNotAllowed, "Method not allowed; use POST")
+		return
+	}
+	defer r.Body.Close()
+
+	if ct := r.Header.Get("Content-Type"); ct != "application/json" {
+		errorhandlers.WriteError(w, http.StatusUnsupportedMediaType, "Content-Type must be application/json")
+		return
+	}
+
+	if err := json.NewDecoder(r.Body).Decode(&doorReq); err != nil {
+		logging.Error(types.ServiceName, err.Error(), "ReadJSON", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Invalid JSON payload: "+err.Error())
+		return
+	}
+
+	now := time.Now()
+	checkIn := time.Date(now.Year(), now.Month(), now.Day(), 23, 0, 0, 0, now.Location())
+	checkOut := checkIn.Add(2 * time.Hour)
+
+	// Ensure dispenser ready (card at encoder) BEFORE we attempt encoding.
+	// With queued dispenser ops, this will not clash with polling.
+	status, err := app.disp.DispenserStart(r.Context())
+	app.SetCardWellStatus(status)
+	if err != nil {
+		logging.Error(types.ServiceName, err.Error(), "Dispense error", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusServiceUnavailable, "Dispense error: "+err.Error())
+		return
+	}
+
+	// build lock server command
+	app.lockserver.BuildCommand(doorReq, checkIn, checkOut)
+
+	// lock server sequence
+	if err := app.lockserver.LockSequence(); err != nil {
+		logging.Error(types.ServiceName, err.Error(), "Key encoding", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusBadGateway, err.Error())
+		return
+	}
+
+	theResponse.Code = http.StatusOK
+	theResponse.Message = "Card issued successfully"
+	w.WriteHeader(http.StatusOK)
+	_ = json.NewEncoder(w).Encode(theResponse)
+}
+
+func (app *App) fetchChipDNAStatus(w http.ResponseWriter, r *http.Request) {
+	const op = logging.Op("fetchChipDNAStatus")
+	var theResponse cmstypes.StatusRec
+
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+	w.Header().Set("Access-Control-Allow-Methods", "POST, OPTIONS")
+	w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+	w.Header().Set("Content-Type", "application/json")
+	status, err := payment.ReadPdqStatus(app.cfg.Hotel, app.cfg.Kiosk)
+	if err != nil {
+		logging.Error(types.ServiceName, err.Error(), "fetchChipDNAStatus", string(op), "", app.cfg.Hotel, app.cfg.Kiosk)
+		errorhandlers.WriteError(w, http.StatusServiceUnavailable, err.Error())
+		return
+	}
+	b, err := json.MarshalIndent(status, "", "  ")
+	if err != nil {
+		logging.Error(types.ServiceName, err.Error(), "MarshalIndent", string(op), "", "", 0)
+		errorhandlers.WriteError(w, http.StatusInternalServerError, "Failed to marshal status data")
+		return
+	}
+	theResponse.Code = http.StatusOK
+	theResponse.Message = string(b)
+	w.WriteHeader(http.StatusOK)
+	_ = json.NewEncoder(w).Encode(theResponse)
+}
+
+func (app *App) onChipDNAError(w http.ResponseWriter, r *http.Request) {
+	const op = logging.Op("onChipDNAError")
+	var tr payment.TransactionResultXML
+	title := "ChipDNA Error"
+	message := ""
+
+	log.Println("onChipDNAError called")
+	w.Header().Set("Access-Control-Allow-Origin", "*")
+	w.Header().Set("Access-Control-Allow-Methods", "POST, OPTIONS")
+	w.Header().Set("Access-Control-Allow-Headers", "Content-Type")
+	w.Header().Set("Content-Type", "application/json")
+
+	if r.Method == http.MethodOptions {
+		w.WriteHeader(http.StatusNoContent)
+		return
+	}
+
+	if r.Method != http.MethodPost {
+		errorhandlers.WriteError(w, http.StatusMethodNotAllowed, "Method not allowed; use POST")
+		return
+	}
+
+	defer r.Body.Close()
+
+	body, err := io.ReadAll(r.Body)
+	if err != nil {
+		message = "Failed to read request body: " + err.Error()
+		mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, title, message)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Unable to read request body")
+		return
+	}
+
+	if len(body) == 0 {
+		message = "Received empty request body"
+		mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, title, message)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Empty body")
+		return
+	}
+
+	if err := tr.ParseTransactionResult(body); err != nil {
+		logging.Error(
+			types.ServiceName,
+			err.Error(),
+			"Parse transaction result error",
+			string(op),
+			"",
+			app.cfg.Hotel,
+			app.cfg.Kiosk,
+		)
+		message = "Failed to parse transaction result: " + err.Error()
+		mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, title, message)
+		errorhandlers.WriteError(w, http.StatusBadRequest, "Invalid XML")
+		return
+	}
+
+	for _, e := range tr.Entries {
+
+		switch e.Key {
+
+		case payment.KeyErrors:
+			mail.SendEmailOnError(app.cfg.Hotel, app.cfg.Kiosk, title, e.Value)
+
+		case payment.KeyIsAvailable:
+			isAvailable := strings.EqualFold(e.Value, "true")
+			app.handleAvailabilityDebounced(isAvailable)
+		}
+
+		logging.Error(
+			types.ServiceName,
+			e.Value,
+			e.Key,
+			string(op),
+			"",
+			app.cfg.Hotel,
+			app.cfg.Kiosk,
+		)
+	}
+
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte(`{"status":"received"}`))
+}
+
+func (app *App) handleAvailabilityDebounced(isAvailable bool) {
+	const (
+		debounceDay   = 30
+		debounceNight = 600
+		title         = "ChipDNA Error"
+	)
+
+	key := app.availabilityKey()
+
+	app.availabilityMu.Lock()
+	defer app.availabilityMu.Unlock()
+
+	// If device becomes available -> cancel pending timer
+	if isAvailable {
+		if t, exists := app.availabilityTimers[key]; exists {
+			t.Stop()
+			delete(app.availabilityTimers, key)
+			log.Println("PDQ availability restored - debounce timer cancelled")
+		}
+		return
+	}
+
+	// Device became unavailable -> start 10s debounce if not already started
+	if _, exists := app.availabilityTimers[key]; exists {
+		return
+	}
+
+	debounce := debounceDay
+
+	hour := time.Now().Hour()
+	if hour < 6 {
+		debounce = debounceNight
+	}
+
+	log.Printf("PDQ reported unavailable - starting %ds debounce timer", debounce)
+
+	timer := time.AfterFunc(time.Duration(debounce)*time.Second, func() {
+		mail.SendEmailOnError(
+			app.cfg.Hotel,
+			app.cfg.Kiosk,
+			title,
+			fmt.Sprintf("ChipDNA PDQ unavailable for more than %d seconds", debounce),
+		)
+
+		app.availabilityMu.Lock()
+		delete(app.availabilityTimers, key)
+		app.availabilityMu.Unlock()
+	})
+
+	app.availabilityTimers[key] = timer
+}
+
+func (app *App) availabilityKey() string {
+	return fmt.Sprintf("hotel=%s|kiosk=%d|app=%p",
+		strings.TrimSpace(app.cfg.Hotel),
+		app.cfg.Kiosk,
+		app,
+	)
+}

hardlink-preauth-release/main.go

@@ -4,6 +4,7 @@ package main
 import (
 	"fmt"
 	"os"
+	"time"
 
 	"gitea.futuresens.co.uk/futuresens/hardlink/bootstrap"
 	"gitea.futuresens.co.uk/futuresens/hardlink/config"
@@ -13,7 +14,7 @@ import (
 )
 
 const (
-	buildVersion = "1.0.0"
+	buildVersion = "1.0.2"
 	serviceName  = "preauth-release"
 )
 
@@ -32,11 +33,17 @@ func main() {
 	defer database.Close()
 
 	if err := payment.ReleasePreauthorizations(database); err != nil {
-		log.WithError(err).Fatal("Preauth release failed")
+		log.Error(err)
+		fmt.Println(err)
+	} else {
+		log.Info("Task completed successfully")
+		fmt.Println("Task completed successfully")
 	}
 
-	log.Info("Task completed successfully")
-	fmt.Println(". Press Enter to exit...")
-	fmt.Scanln()
+	for i := 20; i > 0; i-- {
+		fmt.Printf("\rExiting in %2d seconds...   ", i)
+		time.Sleep(time.Second)
+	}
+	fmt.Println("\rExiting now.            ")
 	os.Exit(0)
 }

lockserver/lockservercommon.go

@@ -102,7 +102,7 @@ func sendAndReceive(conn net.Conn, command []byte) (string, error) {
 		return "", fmt.Errorf("failed to send command: %v", err)
 	}
 
-	conn.SetReadDeadline(time.Now().Add(10 * time.Second))
+	conn.SetReadDeadline(time.Now().Add(20 * time.Second))
 
 	buf := make([]byte, 128)
 	reader := bufio.NewReader(conn)

lockserver/saltolockserver.go

@@ -155,7 +155,7 @@ func (lock *SaltoLockServer) LockSequence() error {
 	reader := bufio.NewReader(conn)
 
 	// 1. Send ENQ
-	log.Infof("Sending ENQ")
+	log.Infof("LockSequence: sending ENQ")
 	if _, e := conn.Write([]byte{ENQ}); e != nil {
 		return fmt.Errorf("failed to send ENQ: %w", e)
 	}
@@ -166,7 +166,7 @@ func (lock *SaltoLockServer) LockSequence() error {
 	}
 
 	// 3. Send command frame
-	log.Infof("Sending encoding command: %q", string(lock.command))
+	log.Infof("LockSequence: sending encoding command: %q", string(lock.command))
 	if _, e := conn.Write(lock.command); e != nil {
 		return fmt.Errorf("failed to send command frame: %w", e)
 	}

mail/mail.go

@@ -0,0 +1,68 @@
+package mail
+
+import (
+	"fmt"
+
+	"gitea.futuresens.co.uk/futuresens/logging"
+	mailjet "github.com/mailjet/mailjet-apiv3-go"
+	log "github.com/sirupsen/logrus"
+)
+
+const (
+	apiKey    = "60f358a27e98562641c08f51e5450c9e"
+	secretKey = "068b65c3b337a0e3c14389544ecd771f"
+)
+
+const (
+	moduleName = "mail"
+)
+
+var (
+	// sendErrorEmail is the e-mail address to which to send an e-mail if there is an error during checkin or payment
+	SendErrorEmails []string
+)
+
+// SendMail will send reception an e-mail
+func SendMail(recipient, title, message string) {
+	const funcName = "SendMail"
+
+	mailjetClient := mailjet.NewMailjetClient(apiKey, secretKey)
+	messagesInfo := []mailjet.InfoMessagesV31{
+		mailjet.InfoMessagesV31{
+			From: &mailjet.RecipientV31{
+				Email: "kiosk@cms.futuresens.co.uk",
+				Name:  "Futuresens Kiosk",
+			},
+			To: &mailjet.RecipientsV31{
+				mailjet.RecipientV31{
+					Email: recipient,
+					Name:  "",
+				},
+			},
+			Subject:  title,
+			TextPart: message,
+		},
+	}
+	messages := mailjet.MessagesV31{Info: messagesInfo}
+	_, err := mailjetClient.SendMailV31(&messages)
+	if err != nil {
+		theFields := log.Fields{}
+		theFields["mailerror"] = true
+		theFields["recipient"] = recipient
+		theFields[logging.LogFunction] = funcName
+		theFields[logging.LogModule] = moduleName
+		theFields[logging.LogError] = err.Error()
+		theFields["error"] = err.Error()
+
+		log.WithFields(theFields).Error("sendmail error")
+	}
+}
+
+func SendEmailOnError(hotel string, kiosk int, title, errMsg string) {
+	log.Println("sendEmailOnError called")
+
+	message := fmt.Sprintf("Hotel: %s, kiosk: %d.\n%s", hotel, kiosk, errMsg)
+	for _, recipient := range SendErrorEmails {
+		SendMail(recipient, title, message)
+	}
+}

mail/mail_test.go

@@ -0,0 +1,9 @@
+package mail
+
+import (
+	"testing"
+)
+
+func Test_SendMail(t *testing.T) {
+	SendMail("zotacrtx5@gmail.com", "Test Subjectp", "Test Message")
+}

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"context"
 	"encoding/xml"
 	"fmt"
 	"net/http"
@@ -18,101 +19,149 @@ import (
 	"gitea.futuresens.co.uk/futuresens/hardlink/bootstrap"
 	"gitea.futuresens.co.uk/futuresens/hardlink/config"
 	"gitea.futuresens.co.uk/futuresens/hardlink/dispenser"
+	"gitea.futuresens.co.uk/futuresens/hardlink/errorhandlers"
 	"gitea.futuresens.co.uk/futuresens/hardlink/handlers"
 	"gitea.futuresens.co.uk/futuresens/hardlink/lockserver"
 	"gitea.futuresens.co.uk/futuresens/hardlink/logging"
+	"gitea.futuresens.co.uk/futuresens/hardlink/mail"
+	"gitea.futuresens.co.uk/futuresens/hardlink/payment"
 	"gitea.futuresens.co.uk/futuresens/hardlink/printer"
 )
 
 const (
-	buildVersion = "1.0.28"
-	serviceName  = "hardlink"
+	buildVersion     = "1.2.5"
+	serviceName      = "hardlink"
+	pollingFrequency = 8 * time.Second
 )
 
 func main() {
 	// Load config
-	config := config.ReadHardlinkConfig()
+	cfg := config.ReadHardlinkConfig()
 	printer.Layout = readTicketLayout()
-	printer.PrinterName = config.PrinterName
-	lockserver.Cert = config.Cert
-	lockserver.LockServerURL = config.LockserverUrl
-	dispHandle := &serial.Port{}
+	printer.PrinterName = cfg.PrinterName
+	lockserver.Cert = cfg.Cert
+	lockserver.LockServerURL = cfg.LockserverUrl
+	mail.SendErrorEmails = cfg.SendErrorEmails
+
+	// Root context for background goroutines
+	// rootCtx, rootCancel := context.WithCancel(context.Background())
+	// defer rootCancel()
+
+	var (
+		dispPort       *serial.Port
+		disp           *dispenser.Client
+		cardWellStatus string
+	)
 
 	// Setup logging and get file handle
-	logFile, err := logging.SetupLogging(config.LogDir, serviceName, buildVersion)
+	logFile, err := logging.SetupLogging(cfg.LogDir, serviceName, buildVersion)
 	if err != nil {
 		log.Printf("Failed to set up logging: %v\n", err)
 	}
-	defer logFile.Close()
+	if logFile != nil {
+		defer logFile.Close()
+	}
 
 	// Initialize dispenser
-	if !config.TestMode {
-		dispenser.SerialPort = config.DispenserPort
-		dispenser.Address = []byte(config.DispenserAdrr)
-		dispHandle, err = dispenser.InitializeDispenser()
-		if err != nil {
-			handlers.FatalError(err)
-		}
-		defer dispHandle.Close()
+	if !cfg.TestMode {
+		dispenser.SerialPort = cfg.DispenserPort
+		dispenser.Address = []byte(cfg.DispenserAdrr)
 
-		status, err := dispenser.CheckDispenserStatus(dispHandle)
+		dispPort, err = dispenser.InitializeDispenser()
 		if err != nil {
-			if len(status) == 0 {
-				err = fmt.Errorf("%s; wrong dispenser address: %s", err, config.DispenserAdrr)
-				handlers.FatalError(err)
-			} else {
-				fmt.Println(status)
-				fmt.Println(err.Error())
-			}
+			mail.SendEmailOnError(cfg.Hotel, cfg.Kiosk, "Dispenser Initialization Error", fmt.Sprintf("Failed to initialize dispenser: %v", err))
+			errorhandlers.FatalError(err)
 		}
-		if status, err = dispenser.DispenserSequence(dispHandle); err != nil {
-			handlers.FatalError(err)
+		defer dispPort.Close()
+
+		disp = dispenser.NewClient(dispPort, 32)
+		defer disp.Close()
+
+		ctx, cancel := context.WithTimeout(context.Background(), 20*time.Second)
+		defer cancel()
+
+		cardWellStatus, err = disp.DispenserPrepare(ctx)
+		if err != nil {
+			err = fmt.Errorf("%s; wrong dispenser address: %s", err, cfg.DispenserAdrr)
+			mail.SendEmailOnError(cfg.Hotel, cfg.Kiosk, "Dispenser Preparation Error", err.Error())
+			errorhandlers.FatalError(err)
 		}
-		log.Infof("Dispenser initialized on port %s, %s", config.DispenserPort, status)
+		fmt.Println(cardWellStatus)
 	}
 
 	// Test lock-server connection
-	switch strings.ToLower(config.LockType) {
+	switch strings.ToLower(cfg.LockType) {
 	case lockserver.TLJ:
-
+		// TLJ uses HTTP - skip TCP probe here
 	default:
-		lockConn, err := lockserver.InitializeServerConnection(config.LockserverUrl)
+		lockConn, err := lockserver.InitializeServerConnection(cfg.LockserverUrl)
 		if err != nil {
 			fmt.Println(err.Error())
 			log.Errorf(err.Error())
+			mail.SendEmailOnError(cfg.Hotel, cfg.Kiosk, "Lock Server Connection Error", err.Error())
 		} else {
-			fmt.Printf("Connected to the lock server successfuly at %s\n", config.LockserverUrl)
-			log.Infof("Connected to the lock server successfuly at %s", config.LockserverUrl)
+			fmt.Printf("Connected to the lock server successfuly at %s\n", cfg.LockserverUrl)
+			log.Infof("Connected to the lock server successfuly at %s", cfg.LockserverUrl)
 			lockConn.Close()
 		}
 	}
 
-	database, err := bootstrap.OpenDB(&config)
+	database, err := bootstrap.OpenDB(&cfg)
 	if err != nil {
 		log.Warnf("DB init failed: %v", err)
 	}
-	defer database.Close()
+	if database != nil {
+		defer database.Close()
+	}
 
-	if config.IsPayment {
+	if cfg.IsPayment {
 		fmt.Println("Payment processing is enabled")
 		log.Info("Payment processing is enabled")
+
 		startChipDnaClient()
+
+		// check ChipDNA and PDQ status and log any errors, but continue running even if it fails
+		go func() {
+			time.Sleep(30 * time.Second) // give ChipDNA client a moment to start
+			pdqstatus, err := payment.ReadPdqStatus(cfg.Hotel, cfg.Kiosk)
+			if err != nil {
+				mail.SendEmailOnError(cfg.Hotel, cfg.Kiosk, "PDQ Status Read Error", err.Error())
+			} else {
+				fmt.Printf("\nPDQ availabile: %v\n", pdqstatus.IsAvailable)
+				log.Infof("PDQ availabile: %v", pdqstatus.IsAvailable)
+			}
+		}()
 	} else {
 		fmt.Println("Payment processing is disabled")
 		log.Info("Payment processing is disabled")
 	}
 
 	// Create App and wire routes
-	app := handlers.NewApp(dispHandle, config.LockType, config.EncoderAddress, database, config.IsPayment)
+	app := handlers.NewApp(disp, cfg.LockType, cfg.EncoderAddress, cardWellStatus, database, &cfg)
+
+	// Update cardWellStatus when dispenser status changes
+	if !cfg.TestMode && disp != nil {
+		// Set initial cardWellStatus
+		app.SetCardWellStatus(cardWellStatus)
+
+		// Set up callback to update cardWellStatus when dispenser status changes
+		disp.OnStockUpdate(func(stock string) {
+			app.SetCardWellStatus(stock)
+		})
+
+		// Start polling for dispenser status every 10 seconds
+		disp.StartPolling(pollingFrequency)
+	}
 
 	mux := http.NewServeMux()
 	app.RegisterRoutes(mux)
 
-	addr := fmt.Sprintf(":%d", config.Port)
+	addr := fmt.Sprintf(":%d", cfg.Port)
 	log.Infof("Starting HTTP server on http://localhost%s", addr)
 	fmt.Printf("Starting HTTP server on http://localhost%s", addr)
+
 	if err := http.ListenAndServe(addr, mux); err != nil {
-		handlers.FatalError(err)
+		errorhandlers.FatalError(err)
 	}
 }
 
@@ -123,12 +172,12 @@ func readTicketLayout() printer.LayoutOptions {
 	// 1) Read the file
 	data, err := os.ReadFile(layoutName)
 	if err != nil {
-		handlers.FatalError(fmt.Errorf("failed to read %s: %v", layoutName, err))
+		errorhandlers.FatalError(fmt.Errorf("failed to read %s: %v", layoutName, err))
 	}
 
 	// 2) Unmarshal into your struct
 	if err := xml.Unmarshal(data, &layout); err != nil {
-		handlers.FatalError(fmt.Errorf("failed to parse %s: %v", layoutName, err))
+		errorhandlers.FatalError(fmt.Errorf("failed to parse %s: %v", layoutName, err))
 	}
 
 	return layout
@@ -147,7 +196,7 @@ func startChipDnaClient() {
 
 	cmd, err := startClient()
 	if err != nil {
-		handlers.FatalError(err)
+		errorhandlers.FatalError(err)
 	}
 
 	// Restart loop
@@ -156,6 +205,7 @@ func startChipDnaClient() {
 			err := cmd.Wait()
 			if err != nil {
 				log.Errorf("ChipDnaClient exited unexpectedly: %v", err)
+				fmt.Printf("ChipDnaClient exited unexpectedly: %v", err)
 				time.Sleep(2 * time.Second)
 				cmd, err = startClient()
 				if err != nil {
@@ -163,6 +213,7 @@ func startChipDnaClient() {
 					return
 				}
 				log.Info("ChipDnaClient restarted successfully")
+				fmt.Printf("ChipDnaClient restarted successfully")
 			}
 		}
 	}()

payment/chipdnastatus.go

@@ -0,0 +1,278 @@
+package payment
+
+import (
+	"bytes"
+	"context"
+	"encoding/xml"
+	"fmt"
+	"html"
+	"io"
+	"net/http"
+	"strings"
+	"time"
+
+	"gitea.futuresens.co.uk/futuresens/hardlink/types"
+	"gitea.futuresens.co.uk/futuresens/logging"
+)
+
+const (
+	KeyErrors                       = "ERRORS"
+	KeyVersionInformation           = "VERSION_INFORMATION"
+	KeyChipDnaStatus                = "CHIPDNA_STATUS"
+	KeyPaymentDeviceStatus          = "PAYMENT_DEVICE_STATUS"
+	KeyRequestQueueStatus           = "REQUEST_QUEUE_STATUS"
+	KeyTmsStatus                    = "TMS_STATUS"
+	KeyPaymentPlatform              = "PAYMENT_PLATFORM_STATUS"
+	KeyPaymentDeviceModel           = "PAYMENT_DEVICE_MODEL"
+	KeyPaymentDeviceIdentifier      = "PAYMENT_DEVICE_IDENTIFIER"
+	KeyIsAvailable                  = "IS_AVAILABLE"
+	KeyAvailabilityError            = "AVAILABILITY_ERROR"
+	KeyAvailabilityErrorInformation = "AVAILABILITY_ERROR_INFORMATION"
+)
+
+type (
+	ArrayOfParameter struct {
+		Parameters []Parameter `xml:"Parameter" json:"Parameters"`
+	}
+
+	Parameter struct {
+		Key   string `xml:"Key" json:"Key"`
+		Value string `xml:"Value" json:"Value"`
+	}
+
+	ServerStatus struct {
+		IsProcessingTransaction bool   `xml:"IsProcessingTransaction" json:"IsProcessingTransaction"`
+		ChipDnaServerIssue      string `xml:"ChipDnaServerIssue" json:"ChipDnaServerIssue"`
+	}
+
+	ArrayOfPaymentDeviceStatus struct {
+		Items []PaymentDeviceStatus `xml:"PaymentDeviceStatus" json:"Items"`
+	}
+
+	PaymentDeviceStatus struct {
+		ConfiguredDeviceId                string `xml:"ConfiguredDeviceId" json:"ConfiguredDeviceId"`
+		ConfiguredDeviceModel             string `xml:"ConfiguredDeviceModel" json:"ConfiguredDeviceModel"`
+		ProcessingTransaction             bool   `xml:"ProcessingTransaction" json:"ProcessingTransaction"`
+		AvailabilityError                 string `xml:"AvailabilityError" json:"AvailabilityError"`
+		AvailabilityErrorInformation      string `xml:"AvailabilityErrorInformation" json:"AvailabilityErrorInformation"`
+		ConfigurationState                string `xml:"ConfigurationState" json:"ConfigurationState"`
+		IsAvailable                       bool   `xml:"IsAvailable" json:"IsAvailable"`
+		BatteryPercentage                 int    `xml:"BatteryPercentage" json:"BatteryPercentage"`
+		BatteryChargingStatus             string `xml:"BatteryChargingStatus" json:"BatteryChargingStatus"`
+		BatteryStatusUpdateDateTime       string `xml:"BatteryStatusUpdateDateTime" json:"BatteryStatusUpdateDateTime"`
+		BatteryStatusUpdateDateTimeFormat string `xml:"BatteryStatusUpdateDateTimeFormat" json:"BatteryStatusUpdateDateTimeFormat"`
+	}
+
+	RequestQueueStatus struct {
+		CreditRequestCount        int `xml:"CreditRequestCount" json:"CreditRequestCount"`
+		CreditConfirmRequestCount int `xml:"CreditConfirmRequestCount" json:"CreditConfirmRequestCount"`
+		CreditVoidRequestCount    int `xml:"CreditVoidRequestCount" json:"CreditVoidRequestCount"`
+		DebitRequestCount         int `xml:"DebitRequestCount" json:"DebitRequestCount"`
+		DebitConfirmRequestCount  int `xml:"DebitConfirmRequestCount" json:"DebitConfirmRequestCount"`
+		DebitVoidRequestCount     int `xml:"DebitVoidRequestCount" json:"DebitVoidRequestCount"`
+	}
+
+	TmsStatus struct {
+		LastConfigUpdateDateTime        string `xml:"LastConfigUpdateDateTime" json:"LastConfigUpdateDateTime"`
+		DaysUntilConfigUpdateIsRequired int    `xml:"DaysUntilConfigUpdateIsRequired" json:"DaysUntilConfigUpdateIsRequired"`
+		RequiredConfigUpdateDateTime    string `xml:"RequiredConfigUpdateDateTime" json:"RequiredConfigUpdateDateTime"`
+	}
+
+	PaymentPlatformStatus struct {
+		MachineLocalDateTime               string `xml:"MachineLocalDateTime" json:"MachineLocalDateTime"`
+		PaymentPlatformLocalDateTime       string `xml:"PaymentPlatformLocalDateTime" json:"PaymentPlatformLocalDateTime"`
+		PaymentPlatformLocalDateTimeFormat string `xml:"PaymentPlatformLocalDateTimeFormat" json:"PaymentPlatformLocalDateTimeFormat"`
+		State                              string `xml:"State" json:"State"`
+	}
+
+	ParsedStatus struct {
+		Errors          []string               `json:"Errors"`
+		VersionInfo     map[string]string      `json:"VersionInfo"`
+		ChipDnaStatus   *ServerStatus          `json:"ChipDnaStatus"`
+		PaymentDevices  []PaymentDeviceStatus  `json:"PaymentDevices"`
+		RequestQueue    *RequestQueueStatus    `json:"RequestQueue"`
+		TMS             *TmsStatus             `json:"TMS"`
+		PaymentPlatform *PaymentPlatformStatus `json:"PaymentPlatform"`
+		Unknown         map[string]string      `json:"Unknown"`
+	}
+)
+
+// ===========================
+// Parser
+// ===========================
+
+func ParseStatusResult(data []byte) (*ParsedStatus, error) {
+	var tr TransactionResultXML
+	if err := tr.ParseTransactionResult(data); err != nil {
+		return nil, fmt.Errorf("unmarshal TransactionResult: %w", err)
+	}
+
+	out := &ParsedStatus{
+		VersionInfo: make(map[string]string),
+		Unknown:     make(map[string]string),
+	}
+
+	for _, e := range tr.Entries {
+		switch e.Key {
+
+		// Some responses return plain text (not escaped XML) for ERRORS.
+		case KeyErrors:
+			msg := html.UnescapeString(e.Value) // safe even if not escaped
+			if msg != "" {
+				out.Errors = append(out.Errors, msg)
+			}
+
+		// Everything below is escaped XML inside <Value>
+		case KeyVersionInformation:
+			unescaped := html.UnescapeString(e.Value)
+
+			var a ArrayOfParameter
+			if err := xml.Unmarshal([]byte(unescaped), &a); err != nil {
+				return nil, fmt.Errorf("unmarshal %s: %w", e.Key, err)
+			}
+			for _, p := range a.Parameters {
+				out.VersionInfo[p.Key] = p.Value
+			}
+
+		case KeyChipDnaStatus:
+			unescaped := html.UnescapeString(e.Value)
+
+			var s ServerStatus
+			if err := xml.Unmarshal([]byte(unescaped), &s); err != nil {
+				return nil, fmt.Errorf("unmarshal %s: %w", e.Key, err)
+			}
+			out.ChipDnaStatus = &s
+
+		case KeyPaymentDeviceStatus:
+			unescaped := html.UnescapeString(e.Value)
+
+			var a ArrayOfPaymentDeviceStatus
+			if err := xml.Unmarshal([]byte(unescaped), &a); err != nil {
+				return nil, fmt.Errorf("unmarshal %s: %w", e.Key, err)
+			}
+			out.PaymentDevices = append(out.PaymentDevices, a.Items...)
+
+		case KeyRequestQueueStatus:
+			unescaped := html.UnescapeString(e.Value)
+
+			var s RequestQueueStatus
+			if err := xml.Unmarshal([]byte(unescaped), &s); err != nil {
+				return nil, fmt.Errorf("unmarshal %s: %w", e.Key, err)
+			}
+			out.RequestQueue = &s
+
+		case KeyTmsStatus:
+			unescaped := html.UnescapeString(e.Value)
+
+			var s TmsStatus
+			if err := xml.Unmarshal([]byte(unescaped), &s); err != nil {
+				return nil, fmt.Errorf("unmarshal %s: %w", e.Key, err)
+			}
+			out.TMS = &s
+
+		case KeyPaymentPlatform:
+			unescaped := html.UnescapeString(e.Value)
+
+			var s PaymentPlatformStatus
+			if err := xml.Unmarshal([]byte(unescaped), &s); err != nil {
+				return nil, fmt.Errorf("unmarshal %s: %w", e.Key, err)
+			}
+			out.PaymentPlatform = &s
+
+		default:
+			// Keep for logging / future additions. Unescape so it's readable XML if it was escaped.
+			out.Unknown[e.Key] = html.UnescapeString(e.Value)
+		}
+	}
+
+	return out, nil
+}
+
+func fetchChipDNAStatus() (*ParsedStatus, error) {
+	const op = logging.Op("fetchChipDNAStatus")
+
+	body := []byte{}
+	client := &http.Client{Timeout: 300 * time.Second}
+	response, err := client.Post(types.LinkChipDNAStatus, "text/xml", bytes.NewBuffer(body))
+	if err != nil {
+		logging.Error(types.ServiceName, err.Error(), "error fetching ChipDNA status", string(op), "", "", 0)
+		return nil, err
+	}
+	defer response.Body.Close()
+
+	body, err = io.ReadAll(response.Body)
+	if err != nil {
+		logging.Error(types.ServiceName, err.Error(), "Read response body error", string(op), "", "", 0)
+		return nil, err
+	}
+
+	result, err := ParseStatusResult(body)
+	if err != nil {
+		logging.Error(types.ServiceName, err.Error(), "Parse ChipDNA status error", string(op), "", "", 0)
+		return nil, err
+	}
+
+	return result, nil
+}
+
+func ReadPdqStatus(hotel string, kiosk int) (PaymentDeviceStatus, error) {
+	const op = logging.Op("readPdqStatus")
+
+	status, err := fetchChipDNAStatus()
+	if err != nil {
+		logging.Error(types.ServiceName, "pdq_unavailable", "Failed to fetch ChipDNA status: "+err.Error(), string(op), "", hotel, kiosk)
+		return PaymentDeviceStatus{}, fmt.Errorf("error fetch ChipDNA status: %w", err)
+	}
+
+	if len(status.Errors) > 0 {
+		msg := strings.Join(status.Errors, "; ")
+		logging.Error(types.ServiceName, "pdq_unavailable", "ChipDNA status errors: "+msg, string(op), "", hotel, kiosk)
+		return PaymentDeviceStatus{}, fmt.Errorf("ChipDNA status errors: %s", msg)
+	}
+
+	if len(status.PaymentDevices) == 0 {
+		logging.Error(types.ServiceName, "pdq_unavailable", "ChipDNA status has no PAYMENT_DEVICE_STATUS items", string(op), "", hotel, kiosk)
+		return PaymentDeviceStatus{}, fmt.Errorf("no payment devices returned")
+	}
+
+	dev := status.PaymentDevices[0]
+	if !dev.IsAvailable {
+		logging.Error(types.ServiceName, "pdq_unavailable", "Payment device unavailable", string(op), "", hotel, kiosk)
+		return dev, fmt.Errorf("device unavailable")
+	}
+
+	return dev, nil
+}
+
+func StartPdqHourlyCheck(ctx context.Context, hotel string, kiosk int) {
+	// waitUntilNextHour(ctx)
+
+	// First execution exactly at round hour
+	_, _ = ReadPdqStatus(hotel, kiosk)
+
+	ticker := time.NewTicker(10 * time.Second)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			_, _ = ReadPdqStatus(hotel, kiosk)
+		}
+	}
+}
+
+func waitUntilNextHour(ctx context.Context) {
+	now := time.Now()
+	next := now.Truncate(time.Hour).Add(time.Hour)
+	d := time.Until(next)
+
+	timer := time.NewTimer(d)
+	defer timer.Stop()
+
+	select {
+	case <-ctx.Done():
+	case <-timer.C:
+	}
+}

payment/creditcall.go

@@ -50,6 +50,12 @@ type (
 		transactionRes   string
 		transactionState string
 	}
+
+	ConfirmTransactionRequest struct {
+		XMLName   xml.Name `xml:"ConfirmTransactionRequest"`
+		Amount    string   `xml:"Amount"`
+		Reference string   `xml:"TransactionReference"`
+	}
 )
 
 // ParseTransactionResult parses the XML into entries.
@@ -72,9 +78,7 @@ func (ti *TransactionInfo) FillFromTransactionResult(trResult TransactionResultX
 }
 
 func (r *PaymentResult) FillFromTransactionResult(trResult TransactionResultXML) {
-	if r.Fields == nil {
-		r.Fields = make(map[string]string)
-	}
+	r.Fields = make(map[string]string)
 
 	for _, e := range trResult.Entries {
 		switch e.Key {
@@ -107,7 +111,7 @@ func BuildPaymentRedirectURL(result map[string]string) string {
 			log.WithField(types.LogResult, result[types.ConfirmResult]).
 				Info("Transaction approved and confirmed")
 
-			return buildSuccessURL(result)
+			return BuildSuccessURL(result)
 		}
 
 		// Not confirmed
@@ -133,7 +137,7 @@ func BuildPreauthRedirectURL(result map[string]string) (string, bool) {
 			log.WithField(types.LogResult, result[types.TransactionResult]).
 				Info("Account verification approved")
 
-			return buildSuccessURL(result), false
+			return BuildSuccessURL(result), false
 
 		// Transaction type Sale?
 		case strings.EqualFold(tType, types.SaleTransactionType):
@@ -141,7 +145,7 @@ func BuildPreauthRedirectURL(result map[string]string) (string, bool) {
 			log.WithField(types.LogResult, result[types.ConfirmResult]).
 				Info("Amount preauthorized successfully")
 
-			return buildSuccessURL(result), true
+			return BuildSuccessURL(result), true
 		}
 	}
 
@@ -149,7 +153,7 @@ func BuildPreauthRedirectURL(result map[string]string) (string, bool) {
 	return BuildFailureURL(res, result[types.Errors]), false
 }
 
-func buildSuccessURL(result map[string]string) string {
+func BuildSuccessURL(result map[string]string) string {
 	q := url.Values{}
 	q.Set("CardNumber", hex.EncodeToString([]byte(result[types.PAN_MASKED])))
 	q.Set("ExpiryDate", hex.EncodeToString([]byte(result[types.EXPIRY_DATE])))

payment/preauthReleaser.go

@@ -21,7 +21,7 @@ const (
 )
 
 /* ==============================
-   Public Entry Point (LEGACY)
+   Public Entry Point
    ============================== */
 
 func ReleasePreauthorizations(database *sql.DB) error {
@@ -78,6 +78,7 @@ func handlePreauthRelease(
 	if err != nil {
 		return err
 	}
+	log.Infof("res=%s state=%s", info.transactionRes, info.transactionState)
 
 	// If already voided or declined → mark released
 	if isAlreadyReleased(info) {
@@ -86,8 +87,7 @@ func handlePreauthRelease(
 
 	// Only void approved + uncommitted
 	if !isVoidable(info) {
-		log.Infof("Preauth %s not eligible for void (res=%s state=%s)",
-			ref, info.transactionRes, info.transactionState)
+		log.Infof("Preauth %s not eligible for void (res=%s state=%s)", ref, info.transactionRes, info.transactionState)
 		return nil
 	}
 

printer/printer.go

@@ -167,7 +167,19 @@ func BuildRoomTicket(details RoomDetailsRec) ([]byte, error) {
 	return buf.Bytes(), nil
 }
 
-func PrintCardholderReceipt(cardholderReceipt string) error {
+func PrintReceipt(receipt string) {
+
+	if len(receipt) == 0 {
+		log.Warn("Empty cardholder receipt, skipping print")
+		return
+	}
+
+	if err := printCardholderReceipt(receipt); err != nil {
+		log.Errorf("PrintCardholderReceipt error: %v", err)
+	}
+}
+
+func printCardholderReceipt(cardholderReceipt string) error {
 	receiptEntries, err := ParseCardholderReceipt([]byte(cardholderReceipt))
 	if err != nil {
 		return fmt.Errorf("ParseCardholderReceipt: %w", err)

release notes.md

@@ -2,6 +2,53 @@
 
 builtVersion is a const in main.go
 
+#### 1.2.5 - 20 March 2026
+removed early return on error when checking dispenser status in the start and final loops.
+
+#### 1.2.4 - 18 March 2026
+added check if keycard at the encoder position before trying to encode key
+
+#### 1.2.3 - 17 March 2026
+added check if keycard at the encoder position before trying to encode key
+
+#### 1.2.2 - 11 February 2026
+increased waiting time befor sending email on PDQ unavailability to 30 seconds day time and 10 minutes night time
+to give it a chance to become available again
+
+#### 1.2.1 - 09 February 2026
+increased waiting time befor sending email on PDQ unavailability to 60 seconds
+
+#### 1.2.0 - 09 February 2026
+added testissuedoorcard endpoint for testing the full workflow of encoding a door card without moving the card out
+added ping-pdq endpoint to check the status of the pdq terminal
+added sending the email on the pdq disconnect event to notify support about the issue
+added sending the email on the dispenser error status to notify support about the issue
+
+#### 1.1.3 - 02 February 2026
+increased timeout for reading response from the Assa abloy lock server to 20 seconds
+
+#### 1.1.2 - 02 February 2026
+added logging for unknown dispenser status positions
+
+#### 1.1.1 - 02 February 2026
+added contionuous polling of the dispenser status every 8 seconds to update the card well status
+
+#### 1.1.0 - 26 January 2026
+divided `/starttransaction` endpoint into two separate endpoints:
+  `/takepreauth` to request preauthorization payment
+  `/takepayment` to request taking payment
+added preauth releaser functionality to release preauthorization payments after a defined time period
+added db connection check before adding a transaction to the database
+and reconnection functionality if the connection to the database is lost
+added `/dispenserstatus` endpoint
+key card always stays at encoder position
+
+#### 1.0.30 - 09 January 2026
+improved logging for preauth releaser
+
+#### 1.0.29 - 08 January 2026
+added count down before exiting the preauth releaser 20 seconds
+
 #### 1.0.28 - 10 December 2025
 added preauth releaser
 

types/types.go

@@ -7,11 +7,13 @@ import (
 )
 
 const (
+	ServiceName                = "hardlink"
 	DateOnly                   = "2006-01-02"
 	CustomLayout               = "2006-01-02 15:04:05 -0700"
-	LinkTakePreauthorization   = "http://127.0.0.1:18181/start-transaction/"
-	LinkTakePayment            = "http://127.0.0.1:18181/start-and-confirm-transaction/"
+	LinkStartTransaction       = "http://127.0.0.1:18181/start-transaction/"
+	LinkConfirmTransaction     = "http://127.0.0.1:18181/confirm-transaction/"
 	LinkTransactionInformation = "http://127.0.0.1:18181/transaction-information/"
+	LinkChipDNAStatus          = "http://127.0.0.1:18181/chipdna-status/"
 	LinkVoidTransaction        = "http://127.0.0.1:18181/void-transaction/"
 	// Transaction types
 	SaleTransactionType     = "sale"
@@ -32,6 +34,7 @@ const (
 	CardReference         = "CARD_REFERENCE"
 	CardHash              = "CARD_HASH"
 	Errors                = "ERRORS"
+	ErrorDescription      = "ERROR_DESCRIPTION"
 	ReceiptData           = "RECEIPT_DATA"
 	ReceiptDataMerchant   = "RECEIPT_DATA_MERCHANT"
 	ReceiptDataCardholder = "RECEIPT_DATA_CARDHOLDER"