package main

import "fmt"
import "time"
import "github.com/warthog618/gpiod"

const wiegand_a = 17
const wiegand_b = 18
const solenoid = 21

var bits [64]bool
var card uint64 = 0
var bitnr uint64 = 0

func openDoor(l *gpiod.Line) {
	fmt.Println("Open")
	l.SetValue(1)
	time.Sleep(500000000)
	l.SetValue(0)
	fmt.Println("Close")
}

func printCardId() {
	fmt.Printf("%d, ", bitnr)
	for i := 0; i < 7; i++ {
		fmt.Printf("%02x", (card>>(8*i))&0xff)
	}
	fmt.Printf("\n")
}

func cardEvent() {
	for i := 63; i != 0; i-- {
		if bits[i] == true {
			card |= 1 << (63 - i)
		}
	}

	printCardId()

	bitnr = 0
	card = 0
}

func wiegandEvent(evt gpiod.LineEvent) {
	if evt.Offset == wiegand_b {
		bits[bitnr] = true
		fmt.Printf("1")
	} else {
		bits[bitnr] = false
		fmt.Printf("0")
	}
	bitnr += 1

	if bitnr == 64 {
		fmt.Printf("\n")
		cardEvent()
	}

}

func main() {
	wa, err := gpiod.RequestLine("gpiochip0", wiegand_a, gpiod.AsInput,
		gpiod.WithFallingEdge, gpiod.WithEventHandler(wiegandEvent))
	if err != nil {
		panic(err)
	}
	wb, err := gpiod.RequestLine("gpiochip0", wiegand_b, gpiod.AsInput,
		gpiod.WithFallingEdge, gpiod.WithEventHandler(wiegandEvent))
	if err != nil {
		panic(err)
	}

	solenoid_line, err := gpiod.RequestLine("gpiochip0", solenoid, gpiod.AsOutput(0))
	if err != nil {
		panic(err)
	}

	openDoor(solenoid_line)

	time.Sleep(time.Minute)
	wa.Close()
	wb.Close()
	fmt.Println("Done")
}