1 files changed, 206 insertions, 0 deletions
diff --git a/ql/status.go b/ql/status.go
new file mode 100644
index 0000000..ab3e675
--- /dev/null
+++ b/ql/status.go
@@ -0,0 +1,206 @@
+package ql
+
+import (
+	"fmt"
+	"io"
+	"strings"
+)
+
+// Status is a decoder for the status packed returned by the printer.
+type Status [32]byte
+
+func (s *Status) MediaWidthMM() int  { return int(s[10]) }
+func (s *Status) MediaLengthMM() int { return int(s[17]) }
+
+type StatusType byte
+
+const (
+	StatusTypeReplyToRequest    StatusType = 0x00
+	StatusTypePrintingCompleted            = 0x01
+	StatusTypeErrorOccurred                = 0x02
+	StatusTypeTurnedOff                    = 0x04
+	StatusTypeNotification                 = 0x05
+	StatusTypePhaseChange                  = 0x06
+)
+
+func (s *Status) Type() StatusType { return StatusType(s[18]) }
+
+type StatusPhase byte
+
+const (
+	StatusPhaseReceiving StatusPhase = 0x00
+	StatusPhasePrinting              = 0x01
+)
+
+func (s *Status) Phase() StatusPhase { return StatusPhase(s[19]) }
+
+func decodeBitfieldErrors(b byte, errors [8]string) []string {
+	var result []string
+	for i := uint(0); i < 8; i++ {
+		if b&(1<<i) != 0 {
+			result = append(result, errors[i])
+		}
+	}
+	return result
+}
+
+func (s *Status) Errors() (errors []string) {
+	errors = append(errors, decodeBitfieldErrors(s[8], [8]string{
+		"no media", "end of media", "cutter jam", "?", "printer in use",
+		"printer turned off", "high-voltage adapter", "fan motor error"})...)
+	errors = append(errors, decodeBitfieldErrors(s[9], [8]string{
+		"replace media", "expansion buffer full", "communication error",
+		"communication buffer full", "cover open", "cancel key",
+		"media cannot be fed", "system error"})...)
+	return
+}
+
+// -----------------------------------------------------------------------------
+
+// String implements the Stringer interface.
+func (s *Status) String() string {
+	var b strings.Builder
+	s.Dump(&b)
+	return b.String()
+}
+
+// Dump writes the status data to an io.Writer in a human-readable format.
+func (s *Status) Dump(f io.Writer) {
+	/*
+		if s[0] != 0x80 || s[1] != 0x20 || s[2] != 0x42 || s[3] != 0x34 {
+			fmt.Fprintln(f, "unexpected status fixed bytes")
+		}
+	*/
+
+	// Model code.
+	switch m := s[4]; m {
+	case 0x38:
+		fmt.Fprintln(f, "model: QL-800")
+	case 0x39:
+		fmt.Fprintln(f, "model: QL-810W")
+	case 0x41:
+		fmt.Fprintln(f, "model: QL-820NWB")
+	case 0x43:
+		fmt.Fprintln(f, "model: QL-1100")
+	case 0x44:
+		fmt.Fprintln(f, "model: QL-1110NWB")
+	case 0x45:
+		fmt.Fprintln(f, "model: QL-1115NWB")
+	default:
+		fmt.Fprintln(f, "model:", m)
+	}
+
+	/*
+		// s[6] seems to be 0x00 in a real-world QL-800, as in QL-1100 docs.
+		if s[5] != 0x30 || s[6] != 0x30 || s[7] != 0x00 {
+			fmt.Fprintln(f, "unexpected status fixed bytes")
+		}
+	*/
+
+	// Error information 1.
+	for _, e := range decodeBitfieldErrors(s[8], [8]string{
+		"no media", "end of media", "cutter jam", "?", "printer in use",
+		"printer turned off", "high-voltage adapter", "fan motor error"}) {
+		fmt.Fprintln(f, "error 1:", e)
+	}
+
+	// Error information 2.
+	for _, e := range decodeBitfieldErrors(s[9], [8]string{
+		"replace media", "expansion buffer full", "communication error",
+		"communication buffer full", "cover open", "cancel key",
+		"media cannot be fed", "system error"}) {
+		fmt.Fprintln(f, "error 2:", e)
+	}
+
+	// Media width.
+	fmt.Fprintln(f, "media width:", s[10], "mm")
+
+	// Media type.
+	switch t := s[11]; t {
+	case 0x00:
+		fmt.Fprintln(f, "media: no media")
+	case 0x4a, 0x0a: // 0x4a = J, in reality we get 0x0a, as in QL-1100 docs.
+		fmt.Fprintln(f, "media: continuous length tape")
+	case 0x4b, 0x0b: // 0x4b = K, in reality we get 0x0b, as in QL-1100 docs.
+		fmt.Fprintln(f, "media: die-cut labels")
+	default:
+		fmt.Fprintln(f, "media:", t)
+	}
+
+	/*
+		// In a real-world QL-800, s[14] seems to be:
+		//  0x01 with die-cut 29mm long labels,
+		//  0x14 with 29mm tape,
+		//  0x23 with red-black 62mm tape,
+		// and directly corresponds to physical pins on the tape.
+		if s[12] != 0x00 || s[13] != 0x00 || s[14] != 0x3f {
+			fmt.Fprintln(f, "unexpected status fixed bytes")
+		}
+	*/
+
+	// Mode.
+	fmt.Fprintln(f, "mode:", s[15])
+
+	/*
+		if s[16] != 0x00 {
+			fmt.Fprintln(f, "unexpected status fixed bytes")
+		}
+	*/
+
+	// Media length.
+	fmt.Fprintln(f, "media length:", s[17], "mm")
+
+	// Status type.
+	switch t := s[18]; t {
+	case 0x00:
+		fmt.Fprintln(f, "status type: reply to status request")
+	case 0x01:
+		fmt.Fprintln(f, "status type: printing completed")
+	case 0x02:
+		fmt.Fprintln(f, "status type: error occurred")
+	case 0x04:
+		fmt.Fprintln(f, "status type: turned off")
+	case 0x05:
+		fmt.Fprintln(f, "status type: notification")
+	case 0x06:
+		fmt.Fprintln(f, "status type: phase change")
+	default:
+		fmt.Fprintln(f, "status type:", t)
+	}
+
+	// Phase type.
+	switch t := s[19]; t {
+	case 0x00:
+		fmt.Fprintln(f, "phase state: receiving state")
+	case 0x01:
+		fmt.Fprintln(f, "phase state: printing state")
+	default:
+		fmt.Fprintln(f, "phase state:", t)
+	}
+
+	// Phase number.
+	fmt.Fprintln(f, "phase number:", int(s[20])*256+int(s[21]))
+
+	// Notification number.
+	switch n := s[22]; n {
+	case 0x00:
+		fmt.Fprintln(f, "notification number: not available")
+	case 0x03:
+		fmt.Fprintln(f, "notification number: cooling (started)")
+	case 0x04:
+		fmt.Fprintln(f, "notification number: cooling (finished)")
+	default:
+		fmt.Fprintln(f, "notification number:", n)
+	}
+
+	/*
+		// In a real-world QL-800, s[25] seems to be:
+		//  0x01 with 29mm tape or die-cut 29mm long labels,
+		//  0x81 with red-black 62mm tape.
+		if s[23] != 0x00 || s[24] != 0x00 || s[25] != 0x00 || s[26] != 0x00 ||
+			s[27] != 0x00 || s[28] != 0x00 || s[29] != 0x00 || s[30] != 0x00 ||
+			s[31] != 0x00 {
+			fmt.Fprintln(f, "unexpected status fixed bytes")
+		}
+	*/
+}