package com.ea.ironmonkey

import android.content.Intent
import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.activity.enableEdgeToEdge
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.material3.Button
import androidx.compose.material3.LinearProgressIndicator
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Scaffold
import androidx.compose.material3.Text
import androidx.compose.material3.darkColorScheme
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableFloatStateOf
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.setValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.text.style.TextAlign
import androidx.compose.ui.unit.dp
import kotlin.concurrent.thread

/**
 * First-launch unpacking of the game data bundled in the APK.
 *
 * Shown only when [GameDataInstaller.isInstalled] is false, so it appears once
 * after install and never again. It exists because copying ~595 MB takes long
 * enough that a tester staring at a frozen launcher would reasonably assume the
 * game had hung.
 */
class GameDataUnpackActivity : ComponentActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        enableEdgeToEdge()
        super.onCreate(savedInstanceState)

        if (GameDataInstaller.isInstalled(this)) {
            startGame()
            return
        }

        var fraction by mutableFloatStateOf(0f)
        var copiedMb by mutableStateOf(0L)
        var totalMb by mutableStateOf(0L)
        var error by mutableStateOf<String?>(null)

        setContent {
            MaterialTheme(colorScheme = darkColorScheme()) {
                UnpackScreen(
                    fraction = fraction,
                    copiedMb = copiedMb,
                    totalMb = totalMb,
                    error = error,
                    onRetry = { recreate() },
                )
            }
        }

        thread(name = "game-data-unpack", isDaemon = true) {
            val result = GameDataInstaller.install(this) { copied, total ->
                // Updating Compose state is safe from any thread; the recomposition
                // is scheduled onto the main thread by the snapshot system.
                fraction = if (total > 0) copied.toFloat() / total else 0f
                copiedMb = copied / 1_048_576
                totalMb = total / 1_048_576
            }
            runOnUiThread {
                when (result) {
                    is GameDataInstaller.Result.Ready -> startGame()
                    is GameDataInstaller.Result.Failed -> error = result.message
                }
            }
        }
    }

    private fun startGame() {
        startActivity(Intent(this, GameActivityMain::class.java))
        finish()
    }
}

@Composable
private fun UnpackScreen(
    fraction: Float,
    copiedMb: Long,
    totalMb: Long,
    error: String?,
    onRetry: () -> Unit,
) {
    Scaffold(modifier = Modifier.fillMaxSize()) { innerPadding ->
        Column(
            modifier = Modifier
                .fillMaxSize()
                .padding(innerPadding)
                .padding(24.dp),
            verticalArrangement = Arrangement.Center,
            horizontalAlignment = Alignment.CenterHorizontally,
        ) {
            if (error != null) {
                Text(
                    text = "Не удалось подготовить игровые данные",
                    style = MaterialTheme.typography.headlineSmall,
                    textAlign = TextAlign.Center,
                )
                Text(
                    text = error,
                    style = MaterialTheme.typography.bodyMedium,
                    textAlign = TextAlign.Center,
                    modifier = Modifier.padding(top = 12.dp),
                )
                Button(onClick = onRetry, modifier = Modifier.padding(top = 24.dp)) {
                    Text("Повторить")
                }
            } else {
                Text(
                    text = "Подготовка игровых данных",
                    style = MaterialTheme.typography.headlineSmall,
                    textAlign = TextAlign.Center,
                )
                Text(
                    text = "Выполняется один раз после установки.",
                    style = MaterialTheme.typography.bodyMedium,
                    color = MaterialTheme.colorScheme.onSurfaceVariant,
                    textAlign = TextAlign.Center,
                    modifier = Modifier.padding(top = 8.dp),
                )
                LinearProgressIndicator(
                    progress = { fraction },
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(top = 24.dp),
                )
                Text(
                    text = if (totalMb > 0) "$copiedMb из $totalMb МБ" else "…",
                    style = MaterialTheme.typography.bodySmall,
                    modifier = Modifier.padding(top = 12.dp),
                )
            }
        }
    }
}