package mt12232a

import (
	"fmt"
	"io"
	"log"
	"time"

	"gitea.unprism.ru/yotia/display-test/pkg/parallel8bit"
	"github.com/stianeikeland/go-rpio/v4"
)

type mt12232a struct {
	logger *log.Logger

	dev parallel8bit.Device

	pinCS  rpio.Pin
	pinRES rpio.Pin
}

type Device interface {
	Reset() error

	WriteCode(cs rpio.State, c byte) error
	WriteData(cs rpio.State, b byte) error
	WriteDatas(cs rpio.State, b []byte) error

	ReadData(cs rpio.State) (byte, error)
	ReadStatus(cs rpio.State) byte

	io.Closer
}

func New(logger *log.Logger) (Device, error) {
	rpio.Open()

	d := mt12232a{
		logger: logger,

		dev: parallel8bit.New(logger, parallel8bit.DevicePins{
			PinA0: rpio.Pin(1), // 19
			PinRW: rpio.Pin(13),
			PinE:  rpio.Pin(12),

			PinDB0: rpio.Pin(22),
			PinDB1: rpio.Pin(10),
			PinDB2: rpio.Pin(9),
			PinDB3: rpio.Pin(11),
			PinDB4: rpio.Pin(21),
			PinDB5: rpio.Pin(20),
			PinDB6: rpio.Pin(26),
			PinDB7: rpio.Pin(16),
		}),

		pinCS:  rpio.Pin(17),
		pinRES: rpio.Pin(27),
	}
	d.pinCS.Output()
	d.pinRES.Output()
	d.dev.Reset()
	d.pinCS.Low()
	d.pinRES.High()

	return &d, nil
}

func (d *mt12232a) Close() error {
	d.pinCS.Low()
	//d.pinRES.Low() // TMP
	d.dev.Pins().PinA0.Low()
	d.dev.Pins().PinE.Low()
	d.dev.Pins().PinRW.Low()
	d.dev.Pins().PinDB0.Low()
	d.dev.Pins().PinDB1.Low()
	d.dev.Pins().PinDB2.Low()
	d.dev.Pins().PinDB3.Low()
	d.dev.Pins().PinDB4.Low()
	d.dev.Pins().PinDB5.Low()
	d.dev.Pins().PinDB6.Low()
	d.dev.Pins().PinDB7.Low()

	return rpio.Close()
}

func (d *mt12232a) status() {
	d.logger.Printf("ST L: %08b R: %08b\n", d.ReadStatus(0)&0xFF, d.ReadStatus(1)&0xFF)
}

func (d *mt12232a) Reset() error {
	d.pinRES.Low()
	time.Sleep(10 * time.Microsecond)
	d.pinRES.High()
	time.Sleep(2 * time.Millisecond)

	return nil
}

// Write codes

func (d *mt12232a) WriteCode(cs rpio.State, c byte) error {
	return d.writeByte(c, 0, cs)
}

// Write data as byte

func (d *mt12232a) WriteData(cs rpio.State, b byte) error {
	return d.writeByte(b, 1, cs)
}

func (d *mt12232a) WriteDatas(cs rpio.State, b []byte) error {
	return d.writeBytes(b, 1, cs)
}

// Read data

func (d *mt12232a) ReadData(cs rpio.State) (byte, error) {
	return d.readByte(1, cs)
}

// Low level functions

func (d *mt12232a) writeByte(b byte, cd, cs rpio.State) error {
	if err := d.waitReady(cs); err != nil {
		return fmt.Errorf("wait ready: %w", err)
	}
	d.pinCS.Write(cs) // Select cristals

	d.dev.WriteByte(b, cd)
	return nil
}

func (d *mt12232a) writeBytes(b []byte, cd, cs rpio.State) error {
	if err := d.waitReady(cs); err != nil {
		return fmt.Errorf("wait ready: %w", err)
	}
	d.pinCS.Write(cs) // Select cristals

	d.dev.WriteBytes(b, cd)
	return nil
}

func (d *mt12232a) readByte(cd, cs rpio.State) (byte, error) {
	// Setup
	if err := d.waitReady(cs); err != nil {
		return 0, fmt.Errorf("wait ready: %w", err)
	}
	d.pinCS.Write(cs) // Select cristals

	return d.dev.ReadByte(cd), nil
}

// Wait, checking status byte
func (d *mt12232a) waitReady(cs rpio.State) error {
	d.pinCS.Write(cs) // Select cristals
	return d.dev.WaitReady()
}

func (d *mt12232a) ReadStatus(cs rpio.State) byte {
	d.pinCS.Write(cs) // Select cristals
	return d.dev.ReadByte(0)
}