package com.unogame.ui.screens

import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.shape.CircleShape
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.foundation.verticalScroll
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.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.text.font.FontWeight
import androidx.compose.ui.text.style.TextAlign
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import com.unogame.ui.theme.*

fun pickRandomHumanName(): String = HUMAN_NAME_PRESETS.random()

@OptIn(ExperimentalMaterial3Api::class)
@Composable
fun LocalSetupScreen(
    playerName: String,
    modeDisplayName: String,
    mode: com.unogame.game.GameMode,
    onStartGame: (Int, String) -> Unit,
    onBack: () -> Unit
) {
    var totalPlayers by remember { mutableIntStateOf(2) }
    var name by remember { mutableStateOf(playerName) }
    var difficulty by remember { mutableStateOf(com.unogame.game.AIDifficulty.NORMAL) }
    val context = androidx.compose.ui.platform.LocalContext.current
    val initMaxHandSize = remember { com.unogame.game.GameRules.loadMaxHandSize(context, mode) }
    var maxHandSize by remember { mutableIntStateOf(initMaxHandSize) }

    val botNames = remember { pickUniqueBotNames(3) }

    Box(
        modifier = Modifier
            .fillMaxSize()
            .background(LocalTableBg.current.color)
    ) {
        Column(
            modifier = Modifier
                .fillMaxSize()
                .verticalScroll(rememberScrollState())
                .padding(24.dp)
        ) {
            Row(
                modifier = Modifier.fillMaxWidth(),
                verticalAlignment = Alignment.CenterVertically
            ) {
                IconButton(onClick = onBack) {
                    Icon(Icons.Default.ArrowBack, "返回", tint = Color.White)
                }
                Text(
                    "本地模式 - $modeDisplayName",
                    fontSize = 24.sp,
                    fontWeight = FontWeight.Bold,
                    color = Color.White
                )
            }

            Spacer(modifier = Modifier.height(32.dp))

            // Player name
            Text("你的名字", color = Color.White.copy(alpha = 0.6f), fontSize = 14.sp)
            Spacer(modifier = Modifier.height(8.dp))
            OutlinedTextField(
                value = name,
                onValueChange = { name = it.take(10) },
                singleLine = true,
                modifier = Modifier.fillMaxWidth(),
                colors = OutlinedTextFieldDefaults.colors(
                    focusedTextColor = Color.White,
                    unfocusedTextColor = Color.White,
                    focusedBorderColor = GoldAccent,
                    unfocusedBorderColor = Color.Gray,
                    cursorColor = GoldAccent
                )
            )
            Spacer(modifier = Modifier.height(8.dp))
            var nameDropdownExpanded by remember { mutableStateOf(false) }
            ExposedDropdownMenuBox(
                expanded = nameDropdownExpanded,
                onExpandedChange = { nameDropdownExpanded = it }
            ) {
                OutlinedTextField(
                    value = "",
                    onValueChange = {},
                    readOnly = true,
                    placeholder = { Text("或选择预设名字", color = Color.White.copy(alpha = 0.4f)) },
                    trailingIcon = { ExposedDropdownMenuDefaults.TrailingIcon(expanded = nameDropdownExpanded) },
                    modifier = Modifier.fillMaxWidth().menuAnchor(),
                    colors = OutlinedTextFieldDefaults.colors(
                        focusedTextColor = Color.White,
                        unfocusedTextColor = Color.White,
                        focusedBorderColor = GoldAccent,
                        unfocusedBorderColor = Color.Gray,
                        cursorColor = GoldAccent
                    )
                )
                ExposedDropdownMenu(
                    expanded = nameDropdownExpanded,
                    onDismissRequest = { nameDropdownExpanded = false }
                ) {
                    HUMAN_NAME_PRESETS.forEach { preset ->
                        DropdownMenuItem(
                            text = { Text(preset) },
                            onClick = {
                                name = preset
                                nameDropdownExpanded = false
                            }
                        )
                    }
                }
            }

            Spacer(modifier = Modifier.height(28.dp))

            // Player count selector
            Text("总玩家数", color = Color.White.copy(alpha = 0.6f), fontSize = 14.sp)
            Spacer(modifier = Modifier.height(12.dp))
            Row(
                modifier = Modifier.fillMaxWidth(),
                horizontalArrangement = Arrangement.SpaceEvenly
            ) {
                listOf(2, 3, 4).forEach { count ->
                    val isSelected = totalPlayers == count
                    Card(
                        modifier = Modifier
                            .size(90.dp)
                            .clickable { totalPlayers = count },
                        shape = RoundedCornerShape(16.dp),
                        colors = CardDefaults.cardColors(
                            containerColor = if (isSelected) GoldAccent else DarkSurface
                        )
                    ) {
                        Box(
                            modifier = Modifier.fillMaxSize(),
                            contentAlignment = Alignment.Center
                        ) {
                            Column(horizontalAlignment = Alignment.CenterHorizontally) {
                                Text(
                                    text = "$count",
                                    fontSize = 32.sp,
                                    fontWeight = FontWeight.Black,
                                    color = if (isSelected) Color.Black else Color.White
                                )
                                Text(
                                    text = "人",
                                    fontSize = 12.sp,
                                    color = if (isSelected) Color.Black.copy(alpha = 0.7f) else Color.White.copy(alpha = 0.5f)
                                )
                            }
                        }
                    }
                }
            }

            Spacer(modifier = Modifier.height(28.dp))

            // AI difficulty
            Text("AI难度", color = Color.White.copy(alpha = 0.6f), fontSize = 14.sp)
            Spacer(modifier = Modifier.height(8.dp))
            Row(
                modifier = Modifier.fillMaxWidth(),
                horizontalArrangement = Arrangement.spacedBy(8.dp)
            ) {
                com.unogame.game.AIDifficulty.values().forEach { d ->
                    val selected = difficulty == d
                    FilterChip(
                        selected = selected,
                        onClick = { difficulty = d },
                        label = { Text(d.displayName, fontSize = 13.sp) },
                        colors = FilterChipDefaults.filterChipColors(
                            selectedContainerColor = when(d) {
                                com.unogame.game.AIDifficulty.EASY -> UnoGreen
                                com.unogame.game.AIDifficulty.NORMAL -> GoldAccent
                                com.unogame.game.AIDifficulty.HARD -> UnoRed
                            },
                            selectedLabelColor = Color.Black
                        )
                    )
                }
            }

            Spacer(modifier = Modifier.height(28.dp))

            // Hand size limit
            Text("手牌上限", color = Color.White.copy(alpha = 0.6f), fontSize = 14.sp)
            Spacer(modifier = Modifier.height(8.dp))
            Row(
                modifier = Modifier.fillMaxWidth(),
                verticalAlignment = Alignment.CenterVertically,
                horizontalArrangement = Arrangement.spacedBy(12.dp)
            ) {
                Slider(
                    value = maxHandSize.toFloat(),
                    onValueChange = { maxHandSize = it.toInt() },
                    valueRange = 0f..20f,
                    steps = 19,
                    modifier = Modifier.weight(1f),
                    colors = SliderDefaults.colors(
                        thumbColor = GoldAccent,
                        activeTrackColor = GoldAccent
                    )
                )
                Text(
                    text = if (maxHandSize == 0) "无限制" else "${maxHandSize}张",
                    color = GoldAccent,
                    fontSize = 16.sp,
                    fontWeight = FontWeight.Bold,
                    modifier = Modifier.width(56.dp)
                )
            }
            Text(
                "0 = 无限制，默认各模式不限制，无情模式默认10张上限",
                color = Color.White.copy(alpha = 0.35f),
                fontSize = 11.sp
            )

            Spacer(modifier = Modifier.height(28.dp))

            // Player list preview
            Text("参与者预览", color = Color.White.copy(alpha = 0.6f), fontSize = 14.sp)
            Spacer(modifier = Modifier.height(12.dp))

            // You
            PlayerSlot(
                name = name.ifBlank { "玩家" },
                isHuman = true,
                isYou = true
            )

            // Bots
            for (i in 1 until totalPlayers) {
                Spacer(modifier = Modifier.height(8.dp))
                PlayerSlot(
                    name = botNames[i - 1],
                    isHuman = false,
                    isYou = false
                )
            }

            Spacer(modifier = Modifier.height(24.dp))

            Button(
                onClick = {
                    com.unogame.game.AIDifficulty.save(context, difficulty)
                    com.unogame.game.GameRules.saveMaxHandSize(context, mode, maxHandSize)
                    onStartGame(totalPlayers, name.ifBlank { "玩家" })
                },
                modifier = Modifier.fillMaxWidth().height(56.dp),
                shape = RoundedCornerShape(16.dp),
                colors = ButtonDefaults.buttonColors(
                    containerColor = GoldAccent,
                    contentColor = Color.Black
                )
            ) {
                Icon(Icons.Default.PlayArrow, null)
                Spacer(modifier = Modifier.width(8.dp))
                Text("开始游戏", fontSize = 18.sp, fontWeight = FontWeight.Bold)
            }

            Spacer(modifier = Modifier.height(16.dp))

            Card(
                modifier = Modifier.fillMaxWidth(),
                shape = RoundedCornerShape(12.dp),
                colors = CardDefaults.cardColors(containerColor = DarkSurface.copy(alpha = 0.5f))
            ) {
                Text(
                    "• 1位真人 + ${totalPlayers - 1}个机器人\n• 支持2-4人局\n• 机器人会自动出牌，无需等待",
                    color = Color.White.copy(alpha = 0.5f),
                    fontSize = 12.sp,
                    lineHeight = 20.sp,
                    modifier = Modifier.padding(16.dp)
                )
            }
        }
    }
}

@Composable
private fun PlayerSlot(
    name: String,
    isHuman: Boolean,
    isYou: Boolean
) {
    Card(
        modifier = Modifier.fillMaxWidth(),
        shape = RoundedCornerShape(12.dp),
        colors = CardDefaults.cardColors(containerColor = DarkSurface)
    ) {
        Row(
            modifier = Modifier.padding(12.dp),
            verticalAlignment = Alignment.CenterVertically
        ) {
            Box(
                modifier = Modifier
                    .size(40.dp)
                    .clip(CircleShape)
                    .background(if (isHuman) GoldAccent else Color.Gray),
                contentAlignment = Alignment.Center
            ) {
                Icon(
                    if (isHuman) Icons.Default.Person else Icons.Default.SmartToy,
                    contentDescription = null,
                    tint = if (isHuman) Color.Black else Color.White,
                    modifier = Modifier.size(24.dp)
                )
            }
            Spacer(modifier = Modifier.width(12.dp))
            Column {
                Text(name, color = Color.White, fontWeight = FontWeight.Bold, fontSize = 16.sp)
                Text(
                    if (isHuman) "真人玩家${if (isYou) " (你)" else ""}" else "AI机器人",
                    color = Color.White.copy(alpha = 0.5f),
                    fontSize = 12.sp
                )
            }
        }
    }
}