package chats.presentation.chat_detail

import android.net.Uri
import androidx.activity.compose.rememberLauncherForActivityResult
import androidx.activity.result.contract.ActivityResultContracts
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.lazy.LazyColumn
import androidx.compose.foundation.lazy.items
import androidx.compose.foundation.lazy.rememberLazyListState
import androidx.compose.material.icons.Icons
import androidx.compose.material.icons.filled.*
import androidx.compose.material3.*
import androidx.compose.runtime.*
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.res.stringResource
import androidx.compose.ui.unit.dp
import chats.presentation.components.EmojiPicker
import chats.presentation.components.MessageBubble
import core.presentation.components.AppAvatar
import core.utils.VoiceRecorder
import core.utils.copyUriToFile
import java.io.File
import ru.knot.messager.R

@OptIn(ExperimentalMaterial3Api::class)
@Composable
fun ChatDetailScreen(
    chatId: String,
    chatName: String,
    viewModel: ChatDetailViewModel,
    onBack: () -> Unit
) {
    val state by viewModel.state.collectAsState()
    val context = LocalContext.current
    val listState = rememberLazyListState()
    val voiceRecorder = remember { VoiceRecorder(context) }
    var textInput by remember { mutableStateOf("") }
    var isEmojiPickerVisible by remember { mutableStateOf(false) }
    var isRecording by remember { mutableStateOf(false) }

    // Пикер галереи
    val galleryLauncher = rememberLauncherForActivityResult(
        contract = ActivityResultContracts.GetContent()
    ) { uri: Uri? ->
        uri?.let {
            val file = copyUriToFile(context, it)
            file?.let { viewModel.uploadMedia(it) }
        }
    }

    // Загрузка данных чата при входе
    LaunchedEffect(chatId) {
        viewModel.setChatId(chatId)
    }

    // Автопрокрутка к последнему сообщению
    LaunchedEffect(state.messages.size) {
        if (state.messages.isNotEmpty()) {
            listState.animateScrollToItem(state.messages.size - 1)
        }
    }

    Scaffold(
        topBar = {
            TopAppBar(
                title = {
                    Row(verticalAlignment = Alignment.CenterVertically) {
                        AppAvatar(
                            url = state.chatAvatar,
                            name = state.chatName ?: chatName,
                            size = 36.dp,
                            modifier = Modifier.padding(end = 8.dp)
                        )
                        Column {
                            Text(state.chatName ?: chatName, style = MaterialTheme.typography.titleMedium)
                            if (state.isTyping) {
                                Text(
                                    stringResource(R.string.typing),
                                    style = MaterialTheme.typography.labelSmall,
                                    color = MaterialTheme.colorScheme.primary
                                )
                            }
                        }
                    }
                },
                navigationIcon = {
                    IconButton(onClick = onBack) {
                        Icon(Icons.Default.ArrowBack, contentDescription = stringResource(R.string.back))
                    }
                },
                actions = {
                    if (state.canCall) {
                        IconButton(onClick = { /* Вызов (WebRTC) */ }) {
                            Icon(Icons.Default.Call, contentDescription = stringResource(R.string.call))
                        }
                        IconButton(onClick = { /* Видеозвонок (WebRTC) */ }) {
                            Icon(Icons.Default.VideoCall, contentDescription = stringResource(R.string.video_call))
                        }
                    }
                }
            )
        }
    ) { paddingValues ->
        Column(
            modifier = Modifier
                .fillMaxSize()
                .padding(paddingValues)
        ) {
            // Список сообщений
            Box(
                modifier = Modifier
                    .weight(1f)
                    .background(MaterialTheme.colorScheme.background)
            ) {
                LazyColumn(
                    state = listState,
                    modifier = Modifier.fillMaxSize(),
                    contentPadding = PaddingValues(16.dp),
                    verticalArrangement = Arrangement.spacedBy(8.dp)
                ) {
                    items(state.messages) { message ->
                        MessageBubble(
                            message = message,
                            isCurrentUser = message.senderId == viewModel.getCurrentUserId(),
                            senderAvatar = if (message.senderId == viewModel.getCurrentUserId()) null else message.senderAvatar,
                            onReactionClick = { emoji -> viewModel.addReaction(message.id, emoji) }
                        )
                    }

                }
                
                if (state.isLoading) {
                    CircularProgressIndicator(modifier = Modifier.align(Alignment.Center))
                }
            }

            // Панель ввода
            Column {
                Row(
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(8.dp),
                    verticalAlignment = Alignment.CenterVertically
                ) {
                    IconButton(onClick = { isEmojiPickerVisible = !isEmojiPickerVisible }) {
                        Icon(
                            Icons.Default.EmojiEmotions, 
                            contentDescription = stringResource(R.string.emoji),
                            tint = if (isEmojiPickerVisible) MaterialTheme.colorScheme.primary else Color.Gray
                        )
                    }
                    IconButton(onClick = { galleryLauncher.launch("*/*") }) {
                        Icon(Icons.Default.AttachFile, contentDescription = stringResource(R.string.attach))
                    }
                    
                    TextField(
                        value = textInput,
                        onValueChange = { textInput = it },
                        modifier = Modifier.weight(1f),
                        placeholder = { Text(stringResource(R.string.message_placeholder)) },
                        maxLines = 4,
                        colors = TextFieldDefaults.colors(
                            focusedIndicatorColor = Color.Transparent,
                            unfocusedIndicatorColor = Color.Transparent
                        )
                    )

                    if (textInput.isBlank()) {
                        IconButton(
                            onClick = {
                                if (!isRecording) {
                                    val file = File(context.cacheDir, "voice_${System.currentTimeMillis()}.mp3")
                                    voiceRecorder.startRecording(file)
                                    isRecording = true
                                } else {
                                    voiceRecorder.stopRecording()
                                    isRecording = false
                                }
                            }
                        ) {
                            Icon(
                                if (isRecording) Icons.Default.Stop else Icons.Default.Mic,
                                contentDescription = stringResource(R.string.voice_message),
                                tint = if (isRecording) Color.Red else Color.Gray
                            )
                        }
                    } else {
                        IconButton(onClick = {
                            viewModel.sendMessage(textInput)
                            textInput = ""
                        }) {
                            Icon(Icons.Default.Send, contentDescription = stringResource(R.string.send))
                        }
                    }
                }
                
                if (isEmojiPickerVisible) {
                    EmojiPicker(onEmojiSelected = { textInput += it })
                }
            }
        }
    }
}