package com.craigvg.lichun_android.ui.screens.retention

import androidx.compose.foundation.background
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.shape.CircleShape
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material.icons.Icons
import androidx.compose.material.icons.filled.CheckCircle
import androidx.compose.material.icons.filled.Diamond
import androidx.compose.material.icons.filled.EmojiEvents
import androidx.compose.material.icons.filled.Link
import androidx.compose.material.icons.filled.LocalFireDepartment
import androidx.compose.material.icons.filled.Schedule
import androidx.compose.material.icons.filled.Star
import androidx.compose.material3.*
import androidx.compose.runtime.Composable
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.graphics.vector.ImageVector
import androidx.compose.ui.unit.dp
import com.craigvg.lichun_android.domain.models.QuestEngagementSnapshot
import com.craigvg.lichun_android.domain.models.WeeklyChallenge
import com.craigvg.lichun_android.ui.theme.AppColors
import com.craigvg.lichun_android.ui.theme.AppSpacing
import com.craigvg.lichun_android.ui.theme.AppTypography

/**
 * Wave 2: the deeper quest loop surface — full-clear streak (+ N-day bonus
 * progress), the rolled weekly challenge with its larger payoff, and a short
 * explainer of quest chains. Read-only status (rewards auto-awarded server-side).
 *
 * Android parity with iOS QuestDepthSection.swift.
 */
@Composable
fun QuestDepthSection(engagement: QuestEngagementSnapshot?) {
    val streak = engagement?.fullClearStreak ?: 0
    val daysToBonus = engagement?.daysToNextBonus ?: QuestEngagementSnapshot.STREAK_BONUS_THRESHOLD
    val weekly = engagement?.weekly

    Column(verticalArrangement = Arrangement.spacedBy(AppSpacing.sm)) {
        FullClearStreakCard(streak = streak, daysToBonus = daysToBonus)
        weekly?.let { WeeklyChallengeCard(it) }
        QuestChainsExplainer()
    }
}

@Composable
private fun FullClearStreakCard(streak: Int, daysToBonus: Int) {
    val reward = QuestEngagementSnapshot.STREAK_BONUS_REWARD
    val subtitle = when {
        streak == 0 -> "Clear all daily quests to start a streak. Reward at ${QuestEngagementSnapshot.STREAK_BONUS_THRESHOLD} days."
        daysToBonus <= 1 -> "1 more full-clear day for a $reward diamond bonus!"
        else -> "$daysToBonus more full-clear days for a $reward diamond bonus."
    }

    Card(
        modifier = Modifier.fillMaxWidth(),
        shape = RoundedCornerShape(AppSpacing.cornerRadius),
        colors = CardDefaults.cardColors(containerColor = AppColors.surfaceElevated),
        elevation = CardDefaults.cardElevation(defaultElevation = 2.dp)
    ) {
        Row(
            modifier = Modifier.padding(AppSpacing.md),
            verticalAlignment = Alignment.CenterVertically
        ) {
            Box(
                modifier = Modifier
                    .size(48.dp)
                    .background(AppColors.warning.copy(alpha = 0.15f), CircleShape),
                contentAlignment = Alignment.Center
            ) {
                Icon(Icons.Default.LocalFireDepartment, null, tint = AppColors.warning, modifier = Modifier.size(24.dp))
            }
            Spacer(Modifier.width(AppSpacing.md))
            Column(modifier = Modifier.weight(1f)) {
                Text("Full-Clear Streak", style = AppTypography.bodyBold, color = AppColors.primaryText)
                Text(subtitle, style = AppTypography.caption, color = AppColors.secondaryText)
            }
            Spacer(Modifier.width(AppSpacing.sm))
            Column(horizontalAlignment = Alignment.CenterHorizontally) {
                Text("$streak", style = AppTypography.title2, color = AppColors.warning)
                Text(if (streak == 1) "day" else "days", style = AppTypography.caption, color = AppColors.secondaryText)
            }
        }
    }
}

@Composable
private fun WeeklyChallengeCard(challenge: WeeklyChallenge) {
    Card(
        modifier = Modifier.fillMaxWidth(),
        shape = RoundedCornerShape(AppSpacing.cornerRadius),
        colors = CardDefaults.cardColors(containerColor = AppColors.surfaceElevated),
        elevation = CardDefaults.cardElevation(defaultElevation = 2.dp)
    ) {
        Column(modifier = Modifier.padding(AppSpacing.md)) {
            Row(verticalAlignment = Alignment.CenterVertically) {
                Box(
                    modifier = Modifier
                        .size(44.dp)
                        .background(AppColors.intelligence.copy(alpha = 0.15f), CircleShape),
                    contentAlignment = Alignment.Center
                ) {
                    Icon(Icons.Default.EmojiEvents, null, tint = AppColors.intelligence, modifier = Modifier.size(20.dp))
                }
                Spacer(Modifier.width(AppSpacing.sm))
                Column(modifier = Modifier.weight(1f)) {
                    Text("Weekly Challenge", style = AppTypography.bodyBold, color = AppColors.primaryText)
                    Text(challenge.description, style = AppTypography.caption, color = AppColors.secondaryText, maxLines = 2)
                }
                Spacer(Modifier.width(AppSpacing.sm))
                WeeklyStatusBadge(challenge)
            }

            if (!challenge.claimed) {
                Spacer(Modifier.height(AppSpacing.sm))
                Row(verticalAlignment = Alignment.CenterVertically) {
                    Text(challenge.progressText, style = AppTypography.captionBold, color = AppColors.primaryText)
                    Spacer(Modifier.weight(1f))
                    Text("${(challenge.progressFraction * 100).toInt()}%", style = AppTypography.caption, color = AppColors.secondaryText)
                }
                Spacer(Modifier.height(AppSpacing.xxs))
                Box(
                    modifier = Modifier
                        .fillMaxWidth()
                        .height(8.dp)
                        .clip(RoundedCornerShape(4.dp))
                        .background(AppColors.intelligence.copy(alpha = 0.2f))
                ) {
                    Box(
                        modifier = Modifier
                            .fillMaxWidth(challenge.progressFraction)
                            .fillMaxHeight()
                            .clip(RoundedCornerShape(4.dp))
                            .background(AppColors.intelligence)
                    )
                }
            }

            Spacer(Modifier.height(AppSpacing.sm))
            Row(verticalAlignment = Alignment.CenterVertically) {
                Icon(Icons.Default.Diamond, null, tint = AppColors.diamond, modifier = Modifier.size(14.dp))
                Spacer(Modifier.width(4.dp))
                Text("${challenge.diamondReward} diamonds", style = AppTypography.captionBold, color = AppColors.primaryText)
                Spacer(Modifier.width(4.dp))
                Text("• bigger weekly payoff", style = AppTypography.caption, color = AppColors.secondaryText)
            }
        }
    }
}

@Composable
private fun WeeklyStatusBadge(challenge: WeeklyChallenge) {
    val (text, icon, color) = when {
        challenge.claimed -> Triple("Earned", Icons.Default.CheckCircle, AppColors.success)
        challenge.completed -> Triple("Complete", Icons.Default.Star, AppColors.accent)
        else -> Triple("Active", Icons.Default.Schedule, AppColors.info)
    }
    Row(
        verticalAlignment = Alignment.CenterVertically,
        modifier = Modifier
            .clip(RoundedCornerShape(AppSpacing.smallCornerRadius))
            .background(color.copy(alpha = 0.15f))
            .padding(horizontal = AppSpacing.sm, vertical = 4.dp)
    ) {
        Icon(icon, null, tint = color, modifier = Modifier.size(12.dp))
        Spacer(Modifier.width(4.dp))
        Text(text, style = AppTypography.caption, color = color)
    }
}

@Composable
private fun QuestChainsExplainer() {
    Row(
        modifier = Modifier
            .fillMaxWidth()
            .clip(RoundedCornerShape(AppSpacing.smallCornerRadius))
            .background(AppColors.primary.copy(alpha = 0.08f))
            .padding(AppSpacing.sm),
        verticalAlignment = Alignment.CenterVertically
    ) {
        Icon(Icons.Default.Link, null, tint = AppColors.primary, modifier = Modifier.size(16.dp))
        Spacer(Modifier.width(AppSpacing.sm))
        Text(
            "Complete a daily quest to unlock a bonus follow-up quest in the same category.",
            style = AppTypography.caption,
            color = AppColors.secondaryText
        )
    }
}