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package com.example.selectimage

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.BackHandler
import androidx.activity.compose.LocalOnBackPressedDispatcherOwner
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.compose.foundation.ExperimentalFoundationApi
import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.combinedClickable
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.lazy.grid.GridCells
import androidx.compose.foundation.lazy.grid.GridItemSpan
import androidx.compose.foundation.lazy.grid.LazyVerticalGrid
import androidx.compose.material3.Checkbox
import androidx.compose.material3.CheckboxColors
import androidx.compose.material3.CheckboxDefaults
import androidx.compose.material3.Scaffold
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.rememberCoroutineScope
import androidx.compose.runtime.setValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.tooling.preview.Preview
import androidx.compose.ui.unit.dp
import com.example.selectimage.ui.theme.SelectImageTheme
import kotlinx.coroutines.launch

class MainActivity : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        enableEdgeToEdge()
        setContent {
            SelectImageTheme {
                Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
                    TimeLine()
                }
            }
        }
        for (i in 0..50) listSelected.add(false)
    }
}

@Composable
fun TimeLine() {
    LazyVerticalGrid(
        columns = GridCells.FixedSize(115.dp),
        horizontalArrangement = Arrangement.spacedBy(5.dp),
        verticalArrangement = Arrangement.spacedBy(5.dp)
    ) {
        items(count = 50, span = { GridItemSpan(1) }) {
            Item(it, onClick = {
                if (SelectedMode == true) {
                    listSelected[it] = !listSelected[it]
                } else listSelected[it] = false
            },
                onLongClick = {
                    if (SelectedMode == false) {
                        SelectedMode = true
                    }
                    if (listSelected[it] == false) listSelected[it] = true
                }
            )
        }
    }
    val onBackPressedDispatcher = LocalOnBackPressedDispatcherOwner.current?.onBackPressedDispatcher
    var backPressHandled by remember { mutableStateOf(false) }
    val coroutineScope = rememberCoroutineScope()
    BackHandler(enabled = !backPressHandled) {
        coroutineScope.launch {
            if(SelectedMode) SelectedMode = false
            else onBackPressedDispatcher?.onBackPressed()
        }
    }
}

val listSelected = mutableListOf<Boolean>()
var SelectedMode = false

@OptIn(ExperimentalFoundationApi::class)
@Composable
fun Item(idx: Int, onClick: () -> Unit, onLongClick: () -> Unit) {
    Box(modifier = Modifier
        .background(color = Color.LightGray)
        .size(115.dp)
        .combinedClickable(
            onClick = { onClick() },
            onLongClick = { onLongClick() }
        ),
        contentAlignment = Alignment.Center
    )
    {
        if (SelectedMode) {
            Checkbox(
                checked = listSelected[idx],
                modifier = Modifier.align(Alignment.TopStart),
                onCheckedChange = {
                    listSelected[idx] = it
                },
                colors = CheckboxDefaults.colors(
                    uncheckedColor = Color.Black,
                    checkedColor = Color.White,
                    checkmarkColor = Color.Blue
                )
            )
        }
        Text(text = idx.toString(), color = Color.Black)
    }
}

//bam nut quay lai