package mz700_tape_wav_gen

import (
	"fmt"
	"io"
	"math"
)

type StandardTapeWaveGenerator struct {
	InnerWaveGen *MZ700TapeWavGen
	LastError    error
}

func NewStandardTapeWaveGenerator(f io.WriteCloser, machineType MachineType, invertPolarity bool) (*StandardTapeWaveGenerator, error) {
	iwg, err := NewMZ700TapeWavGen(f, machineType, invertPolarity)
	if err != nil {
		return nil, err
	}
	g := &StandardTapeWaveGenerator{
		InnerWaveGen: iwg,
	}
	return g, nil
}

func (g *StandardTapeWaveGenerator) WriteStandardFile(f *StandardTapeFile) error {
	g.InnerWaveGen.WriteGAP(true)
	g.InnerWaveGen.WriteTapeMark(true)
	g.InnerWaveGen.WriteLongPulse()
	g.writeTapeHeader(f)
	g.InnerWaveGen.Write256S()
	g.writeTapeHeader(f)
	g.InnerWaveGen.WriteGAP(false)
	g.InnerWaveGen.WriteTapeMark(false)
	g.InnerWaveGen.WriteLongPulse()
	fchksum := GetByteSliceChecksum(f.File)
	_, _ = g.InnerWaveGen.Write(f.File)
	g.InnerWaveGen.WriteUint16BigEndian(fchksum)
	g.InnerWaveGen.WriteLongPulse()
	g.InnerWaveGen.Write256S()
	_, _ = g.InnerWaveGen.Write(f.File)
	g.InnerWaveGen.WriteUint16BigEndian(fchksum)
	g.InnerWaveGen.WriteLongPulse()
	return g.LastError
}

func (g *StandardTapeWaveGenerator) writeTapeHeader(f *StandardTapeFile) {
	var hdr_chksum uint16
	hdr_chksum = 0
	hdr_chksum += GetSingleByteChecksum(f.FileAttribute)
	g.InnerWaveGen.WriteFileAttribute(f.FileAttribute)
	fdata := ConvertFilename(f.Filename)
	hdr_chksum += g.InnerWaveGen.WriteFilenameRaw(fdata)
	filelenRaw := len(f.File)
	if filelenRaw > math.MaxUint16 {
		g.LastError = fmt.Errorf("file too long (%d/%d bytes)", filelenRaw, math.MaxUint16)
	}
	filelen := uint16(filelenRaw)
	hdr_chksum += g.InnerWaveGen.WriteUint16LittleEndian(filelen)
	hdr_chksum += g.InnerWaveGen.WriteUint16LittleEndian(f.LoadAddress)
	if f.ExecuteAfterLoad {
		hdr_chksum += g.InnerWaveGen.WriteUint16LittleEndian(f.ExecuteAddress)
	} else {
		hdr_chksum += g.InnerWaveGen.WriteUint16LittleEndian(0x00AD)
	}
	if f.IsStringComment {
		ctw := ConvertStringCommnet(f.StringComment)
		hdr_chksum += g.InnerWaveGen.WriteCommentRaw(ctw)
	} else {
		hdr_chksum += g.InnerWaveGen.WriteCommentRaw(f.BinaryComment)
	}
	g.InnerWaveGen.WriteUint16BigEndian(hdr_chksum)
	g.InnerWaveGen.WriteLongPulse()
}

func (g *StandardTapeWaveGenerator) WriteSilent1Second() {
	g.InnerWaveGen.WriteSilent1Second()
}

func (g *StandardTapeWaveGenerator) Close() error {
	err := g.InnerWaveGen.Close()
	if err != nil {
		return err
	} else {
		return g.LastError
	}
}

func (g *StandardTapeWaveGenerator) GetLastError() error {
	return g.LastError
}