package com.example.barcodecomposetemplate

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.compose.foundation.Canvas
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.Scaffold
import androidx.compose.runtime.Composable
import androidx.compose.ui.Modifier
import androidx.compose.ui.geometry.Offset
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.unit.dp
import com.example.barcodecomposetemplate.ui.theme.BarcodeComposeTemplateTheme

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContent {
            BarcodeComposeTemplateTheme {
                Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                    BarcodeExample(
                        modifier = Modifier
                            .padding(innerPadding)
                            .padding(all = 32.dp)
                    )
                }
            }
        }
    }
}

// UPC-A L a R patterny
private val Lp = intArrayOf(
    0x0D, // 0001101
    0x19, // 0011001
    0x13, // 0010011
    0x3D, // 0111101
    0x23, // 0100011
    0x31, // 0110001
    0x2F, // 0101111
    0x3B, // 0111011
    0x37, // 0110111
    0x0B  // 0001011
)

private val Rp = intArrayOf(
    0x72, // 1110010
    0x66, // 1100110
    0x6C, // 1101100
    0x42, // 1000010
    0x5C, // 1011100
    0x4E, // 1001110
    0x50, // 1010000
    0x44, // 1000100
    0x48, // 1001000
    0x74  // 1110100
)

// Ukazaka vykreslovani
@Composable
fun BarcodeExample(
    modifier: Modifier = Modifier
) {
    Canvas(modifier = modifier) {
        // Rozmery pro obdelnik
        val rectWidth = 600f
        val rectHeight = 200f

        // Bily obdelnik (pozadi)
        drawRect(
            color = Color.White,
            topLeft = Offset(0f, 0f),
            size = androidx.compose.ui.geometry.Size(rectWidth, rectHeight)
        )


        // Uhlopricka z leveho horniho do praveho dolniho rohu
        drawLine(
            color = Color.Black,
            start = Offset(0f, 0f),
            end = Offset(rectWidth, rectHeight),
            strokeWidth = 2f
        )

    }
}