package cc.unitmesh.devins.ui.compose.agent.codereview

import androidx.compose.animation.AnimatedVisibility
import androidx.compose.animation.expandVertically
import androidx.compose.animation.fadeIn
import androidx.compose.animation.fadeOut
import androidx.compose.animation.shrinkVertically
import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.horizontalScroll
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.Spacer
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.lazy.LazyColumn
import androidx.compose.foundation.rememberScrollState
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material3.ButtonDefaults
import androidx.compose.material3.Card
import androidx.compose.material3.CardDefaults
import androidx.compose.material3.FilledTonalButton
import androidx.compose.material3.Icon
import androidx.compose.material3.MaterialTheme
import androidx.compose.material3.Surface
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
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.text.font.FontFamily
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 cc.unitmesh.agent.codereview.ModifiedCodeRange
import cc.unitmesh.agent.linter.LintFileResult
import cc.unitmesh.agent.linter.LintIssue
import cc.unitmesh.devins.ui.compose.agent.ComposeRenderer
import cc.unitmesh.devins.ui.compose.icons.AutoDevComposeIcons
import cc.unitmesh.devins.ui.compose.theme.AutoDevColors

/**
 * Right panel: AI code review messages
 */
@Composable
fun CodeReviewAgentPanel(
    state: CodeReviewState,
    viewModel: CodeReviewViewModel,
    renderer: ComposeRenderer,
    modifier: Modifier = Modifier
) {
    Column(
        modifier = modifier
            .fillMaxSize()
            .background(MaterialTheme.colorScheme.surface)
    ) {
        Card(
            modifier = Modifier.fillMaxWidth(),
            colors = CardDefaults.cardColors(
                containerColor = MaterialTheme.colorScheme.surfaceVariant
            ),
            shape = RoundedCornerShape(topStart = 0.dp, topEnd = 0.dp, bottomStart = 6.dp, bottomEnd = 6.dp)
        ) {
            Row(
                modifier = Modifier
                    .fillMaxWidth()
                    .padding(12.dp),
                horizontalArrangement = Arrangement.SpaceBetween,
                verticalAlignment = Alignment.Companion.CenterVertically
            ) {
                when (state.aiProgress.stage) {
                    AnalysisStage.IDLE -> {
                        FilledTonalButton(
                            onClick = { viewModel.startAnalysis() },
                            enabled = state.diffFiles.isNotEmpty()
                        ) {
                            Icon(
                                imageVector = AutoDevComposeIcons.PlayArrow,
                                contentDescription = "Start",
                                modifier = Modifier.size(18.dp)
                            )
                            Spacer(modifier = Modifier.width(4.dp))
                            Text("Start Review")
                        }
                    }
                    AnalysisStage.RUNNING_LINT,
                    AnalysisStage.ANALYZING_LINT,
                    AnalysisStage.GENERATING_PLAN,
                    AnalysisStage.WAITING_FOR_USER_INPUT,
                    AnalysisStage.GENERATING_FIX -> {
                        FilledTonalButton(
                            onClick = { viewModel.cancelAnalysis() },
                            colors = ButtonDefaults.filledTonalButtonColors(
                                containerColor = AutoDevColors.Red.c600.copy(alpha = 0.2f),
                                contentColor = AutoDevColors.Red.c600
                            )
                        ) {
                            Icon(
                                imageVector = AutoDevComposeIcons.Stop,
                                contentDescription = "Stop",
                                modifier = Modifier.size(18.dp)
                            )
                            Spacer(modifier = Modifier.width(4.dp))
                            Text("Stop")
                        }
                    }
                    AnalysisStage.COMPLETED -> {
                        Row(
                            horizontalArrangement = Arrangement.spacedBy(8.dp),
                            verticalAlignment = Alignment.Companion.CenterVertically
                        ) {
                            Surface(
                                color = AutoDevColors.Green.c600,
                                shape = RoundedCornerShape(4.dp)
                            ) {
                                Row(
                                    modifier = Modifier.padding(horizontal = 8.dp, vertical = 4.dp),
                                    horizontalArrangement = Arrangement.spacedBy(4.dp),
                                    verticalAlignment = Alignment.Companion.CenterVertically
                                ) {
                                    Icon(
                                        imageVector = AutoDevComposeIcons.CheckCircle,
                                        contentDescription = null,
                                        tint = Color.White,
                                        modifier = Modifier.size(14.dp)
                                    )
                                    Text(
                                        text = "Complete",
                                        style = MaterialTheme.typography.labelSmall,
                                        color = Color.White,
                                        fontWeight = FontWeight.Companion.Bold
                                    )
                                }
                            }

                            FilledTonalButton(
                                onClick = { viewModel.startAnalysis() },
                                colors = ButtonDefaults.filledTonalButtonColors(
                                    containerColor = AutoDevColors.Indigo.c600,
                                    contentColor = Color.White
                                ),
                                modifier = Modifier.height(32.dp)
                            ) {
                                Icon(
                                    imageVector = AutoDevComposeIcons.Refresh,
                                    contentDescription = null,
                                    modifier = Modifier.size(14.dp)
                                )
                                Spacer(modifier = Modifier.width(4.dp))
                                Text(
                                    text = "Restart review",
                                    style = MaterialTheme.typography.labelSmall
                                )
                            }
                        }
                    }

                    AnalysisStage.ERROR -> {
                        Row(
                            horizontalArrangement = Arrangement.spacedBy(4.dp),
                            verticalAlignment = Alignment.Companion.CenterVertically
                        ) {
                            Icon(
                                imageVector = AutoDevComposeIcons.Error,
                                contentDescription = "Error",
                                tint = AutoDevColors.Red.c600,
                                modifier = Modifier.size(18.dp)
                            )
                            Text(
                                text = "Error",
                                style = MaterialTheme.typography.bodyMedium,
                                color = AutoDevColors.Red.c600
                            )
                        }
                    }
                }
            }
        }

        Box(
            modifier = Modifier
                .fillMaxSize()
                .padding(8.dp)
        ) {
            if (state.aiProgress.stage == AnalysisStage.IDLE && state.aiProgress.lintResults.isEmpty()) {
                Column(
                    modifier = Modifier
                        .fillMaxSize()
                        .padding(32.dp),
                    horizontalAlignment = Alignment.Companion.CenterHorizontally,
                    verticalArrangement = Arrangement.Center
                ) {
                    Icon(
                        imageVector = AutoDevComposeIcons.Info,
                        contentDescription = null,
                        tint = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.5f),
                        modifier = Modifier.size(48.dp)
                    )
                    Spacer(modifier = Modifier.height(16.dp))
                    Text(
                        text = "Click 'Start Review' to analyze the code changes with AI",
                        style = MaterialTheme.typography.bodyMedium,
                        color = MaterialTheme.colorScheme.onSurfaceVariant,
                        textAlign = TextAlign.Center
                    )
                }
            } else {
                LazyColumn(
                    modifier = Modifier.fillMaxSize(),
                    verticalArrangement = Arrangement.spacedBy(8.dp)
                ) {
                    if (state.aiProgress.lintResults.isNotEmpty() || state.aiProgress.lintOutput.isNotEmpty()) {
                        item {
                            CollapsibleLintAnalysisCard(
                                lintResults = state.aiProgress.lintResults,
                                lintOutput = state.aiProgress.lintOutput,
                                isActive = state.aiProgress.stage == AnalysisStage.RUNNING_LINT,
                                diffFiles = state.diffFiles,
                                modifiedCodeRanges = state.aiProgress.modifiedCodeRanges
                            )
                        }
                    }

                    if (state.aiProgress.analysisOutput.isNotEmpty()) {
                        item {
                            AIAnalysisSection(
                                analysisOutput = state.aiProgress.analysisOutput,
                                isActive = state.aiProgress.stage == AnalysisStage.ANALYZING_LINT
                            )
                        }
                    }

                    if (state.aiProgress.planOutput.isNotEmpty()) {
                        item {
                            var selectedPlanItems by remember { mutableStateOf<Set<Int>>(emptySet()) }

                            ModificationPlanSection(
                                planOutput = state.aiProgress.planOutput,
                                isActive = state.aiProgress.stage == AnalysisStage.GENERATING_PLAN,
                                selectedItems = selectedPlanItems,
                                onItemSelectionChanged = { newSelection ->
                                    selectedPlanItems = newSelection
                                    viewModel.setSelectedPlanItems(newSelection)
                                },
                                onFileLinkClick = { filePath ->
                                    viewModel.openFile(filePath)
                                }
                            )
                        }
                    }

                    if (state.aiProgress.stage == AnalysisStage.WAITING_FOR_USER_INPUT) {
                        item {
                            UserInputSection(
                                onGenerate = { feedback ->
                                    viewModel.proceedToGenerateFixes(feedback)
                                },
                                onCancel = {
                                    viewModel.cancelAnalysis()
                                }
                            )
                        }
                    }

                    if (state.aiProgress.fixRenderer != null || state.aiProgress.stage == AnalysisStage.GENERATING_FIX) {
                        item {
                            SuggestedFixesAgentView(
                                fixRenderer = state.aiProgress.fixRenderer,
                                isGenerating = state.aiProgress.stage == AnalysisStage.GENERATING_FIX,
                                onOpenFileViewer = { filePath ->
                                    viewModel.openFile(filePath)
                                }
                            )
                        }
                    }
                }
            }
        }

        // File viewer dialog (same API as CodeReviewSideBySideView)
        state.fileViewerPath?.let { filePath ->
            FileViewerDialog(
                filePath = filePath,
                onClose = { viewModel.closeFileViewer() },
                startLine = state.fileViewerStartLine,
                endLine = state.fileViewerEndLine
            )
        }
    }
}

/**
 * Collapsible Lint Analysis Card with per-file breakdown
 */
@Composable
fun CollapsibleLintAnalysisCard(
    lintResults: List<LintFileResult>,
    lintOutput: String,
    isActive: Boolean,
    diffFiles: List<DiffFileInfo> = emptyList(),
    modifiedCodeRanges: Map<String, List<ModifiedCodeRange>> = emptyMap(),
    modifier: Modifier = Modifier
) {
    var isExpanded by remember { mutableStateOf(true) }

    val totalErrors = lintResults.sumOf { it.errorCount }
    val totalWarnings = lintResults.sumOf { it.warningCount }
    val totalInfos = lintResults.sumOf { it.infoCount }

    // Calculate chunk count and modified lines
    val totalChunks = diffFiles.sumOf { it.hunks.size }
    val modifiedLines = diffFiles.sumOf { file ->
        file.hunks.sumOf { hunk ->
            hunk.lines.count { line ->
                line.type == cc.unitmesh.agent.diff.DiffLineType.ADDED ||
                line.type == cc.unitmesh.agent.diff.DiffLineType.DELETED
            }
        }
    }

    Card(
        modifier = modifier.fillMaxWidth(),
        colors = CardDefaults.cardColors(
            containerColor = if (isActive) {
                AutoDevColors.Indigo.c600.copy(alpha = 0.1f)
            } else {
                MaterialTheme.colorScheme.surfaceVariant
            }
        ),
        shape = RoundedCornerShape(6.dp)
    ) {
        Column(modifier = Modifier.fillMaxWidth()) {
            // Header
            Row(
                modifier = Modifier
                    .fillMaxWidth()
                    .clickable { isExpanded = !isExpanded }
                    .padding(12.dp),
                horizontalArrangement = Arrangement.SpaceBetween,
                verticalAlignment = Alignment.Companion.CenterVertically
            ) {
                Row(
                    verticalAlignment = Alignment.Companion.CenterVertically,
                    horizontalArrangement = Arrangement.spacedBy(8.dp)
                ) {
                    Icon(
                        imageVector = if (isExpanded) AutoDevComposeIcons.ExpandMore else AutoDevComposeIcons.ChevronRight,
                        contentDescription = if (isExpanded) "Collapse" else "Expand",
                        tint = MaterialTheme.colorScheme.onSurfaceVariant,
                        modifier = Modifier.size(20.dp)
                    )

                    Text(
                        text = "Code Audit",
                        style = MaterialTheme.typography.titleSmall,
                        fontWeight = FontWeight.Companion.Bold,
                        color = MaterialTheme.colorScheme.onSurface
                    )

                    if (isActive) {
                        Surface(
                            color = AutoDevColors.Indigo.c600,
                            shape = RoundedCornerShape(4.dp)
                        ) {
                            Text(
                                text = "RUNNING",
                                style = MaterialTheme.typography.labelSmall,
                                color = Color.Companion.White,
                                modifier = Modifier.padding(horizontal = 6.dp, vertical = 2.dp)
                            )
                        }
                    }
                }

                // Issue counts and modification stats
                Row(
                    horizontalArrangement = Arrangement.spacedBy(12.dp),
                    verticalAlignment = Alignment.Companion.CenterVertically
                ) {
                    if (totalErrors > 0) {
                        IssueBadge(
                            count = totalErrors,
                            color = AutoDevColors.Red.c600,
                            label = "E"
                        )
                    }
                    if (totalWarnings > 0) {
                        IssueBadge(
                            count = totalWarnings,
                            color = AutoDevColors.Amber.c600,
                            label = "W"
                        )
                    }
                    if (totalInfos > 0) {
                        IssueBadge(
                            count = totalInfos,
                            color = AutoDevColors.Blue.c600,
                            label = "I"
                        )
                    }

                    // Chunk and line modification stats
                    if (totalChunks > 0) {
                        Text(
                            text = "|",
                            style = MaterialTheme.typography.bodySmall,
                            color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.3f)
                        )

                        Row(
                            horizontalArrangement = Arrangement.spacedBy(4.dp),
                            verticalAlignment = Alignment.Companion.CenterVertically
                        ) {
                            Text(
                                text = "$totalChunks chunks",
                                style = MaterialTheme.typography.labelSmall,
                                color = MaterialTheme.colorScheme.onSurfaceVariant,
                                fontWeight = FontWeight.Companion.Medium
                            )
                            Text(
                                text = "•",
                                style = MaterialTheme.typography.labelSmall,
                                color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.5f)
                            )
                            Text(
                                text = "$modifiedLines lines",
                                style = MaterialTheme.typography.labelSmall,
                                color = MaterialTheme.colorScheme.onSurfaceVariant,
                                fontWeight = FontWeight.Companion.Medium
                            )
                        }
                    }
                }
            }

            AnimatedVisibility(
                visible = isExpanded,
                enter = expandVertically() + fadeIn(),
                exit = shrinkVertically() + fadeOut()
            ) {
                Column(
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(horizontal = 12.dp, vertical = 0.dp)
                ) {
                    // Show lint results per file
                    if (lintResults.isNotEmpty()) {
                        lintResults.forEach { fileResult ->
                            // Try to find matching modified ranges
                            // fileResult.filePath might be absolute or relative, modifiedCodeRanges keys are usually relative
                            // We'll try exact match and suffix match
                            val modifiedRanges = modifiedCodeRanges[fileResult.filePath]
                                ?: modifiedCodeRanges.entries.find { fileResult.filePath.endsWith(it.key) }?.value
                                ?: emptyList()

                            FileLintResultCard(
                                fileResult = fileResult,
                                modifiedRanges = modifiedRanges
                            )
                            Spacer(modifier = Modifier.height(8.dp))
                        }
                    } else {
                        // Fallback to raw output
                        Text(
                            text = lintOutput,
                            style = MaterialTheme.typography.bodySmall,
                            fontFamily = FontFamily.Companion.Monospace,
                            color = MaterialTheme.colorScheme.onSurfaceVariant,
                            modifier = Modifier.padding(bottom = 12.dp)
                        )
                    }
                }
            }
        }
    }
}

/**
 * Individual file lint result card (collapsible)
 */
@Composable
fun FileLintResultCard(
    fileResult: LintFileResult,
    modifiedRanges: List<ModifiedCodeRange> = emptyList(),
    modifier: Modifier = Modifier
) {
    var isExpanded by remember { mutableStateOf(false) }

    Card(
        modifier = modifier.fillMaxWidth(),
        colors = CardDefaults.cardColors(
            containerColor = MaterialTheme.colorScheme.surface
        ),
        shape = RoundedCornerShape(4.dp)
    ) {
        Column(modifier = Modifier.fillMaxWidth()) {
            // File header
            Row(
                modifier = Modifier
                    .fillMaxWidth()
                    .clickable { isExpanded = !isExpanded }
                    .padding(8.dp),
                horizontalArrangement = Arrangement.SpaceBetween,
                verticalAlignment = Alignment.Companion.CenterVertically
            ) {
                Row(
                    verticalAlignment = Alignment.Companion.CenterVertically,
                    horizontalArrangement = Arrangement.spacedBy(6.dp)
                ) {
                    Icon(
                        imageVector = if (isExpanded) AutoDevComposeIcons.ExpandMore else AutoDevComposeIcons.ChevronRight,
                        contentDescription = if (isExpanded) "Collapse" else "Expand",
                        tint = MaterialTheme.colorScheme.onSurfaceVariant,
                        modifier = Modifier.size(16.dp)
                    )

                    Text(
                        text = fileResult.filePath.substringAfterLast("/"),
                        style = MaterialTheme.typography.bodySmall,
                        fontFamily = FontFamily.Companion.Monospace,
                        fontWeight = FontWeight.Companion.SemiBold,
                        color = MaterialTheme.colorScheme.onSurface
                    )
                }

                Row(
                    horizontalArrangement = Arrangement.spacedBy(8.dp),
                    verticalAlignment = Alignment.Companion.CenterVertically
                ) {
                    if (fileResult.errorCount > 0) {
                        IssueBadge(
                            count = fileResult.errorCount,
                            color = AutoDevColors.Red.c600,
                            label = "E"
                        )
                    }
                    if (fileResult.warningCount > 0) {
                        IssueBadge(
                            count = fileResult.warningCount,
                            color = AutoDevColors.Amber.c600,
                            label = "W"
                        )
                    }
                    if (fileResult.infoCount > 0) {
                        IssueBadge(
                            count = fileResult.infoCount,
                            color = AutoDevColors.Blue.c600,
                            label = "I"
                        )
                    }
                }
            }

            // Issues list
            AnimatedVisibility(
                visible = isExpanded,
                enter = expandVertically() + fadeIn(),
                exit = shrinkVertically() + fadeOut()
            ) {
                Column(
                    modifier = Modifier
                        .fillMaxWidth()
                        .padding(horizontal = 8.dp, vertical = 0.dp)
                ) {
                    // Display modified ranges if available
                    val namedRanges = modifiedRanges.filter { it.elementName != "unknown" }
                    if (namedRanges.isNotEmpty()) {
                        // Use a horizontal scroll row for tags to ensure compatibility
                        Row(
                            modifier = Modifier
                                .fillMaxWidth()
                                .horizontalScroll(rememberScrollState())
                                .padding(bottom = 8.dp),
                            horizontalArrangement = Arrangement.spacedBy(4.dp),
                            verticalAlignment = Alignment.CenterVertically
                        ) {
                            namedRanges.forEach { range ->
                                Surface(
                                    color = MaterialTheme.colorScheme.surfaceVariant,
                                    shape = RoundedCornerShape(4.dp),
                                    border = androidx.compose.foundation.BorderStroke(
                                        1.dp,
                                        MaterialTheme.colorScheme.outline.copy(alpha = 0.3f)
                                    )
                                ) {
                                    Row(
                                        modifier = Modifier.padding(horizontal = 6.dp, vertical = 2.dp),
                                        verticalAlignment = Alignment.CenterVertically,
                                        horizontalArrangement = Arrangement.spacedBy(4.dp)
                                    ) {
                                        // Optional: Icon based on elementType
                                        Text(
                                            text = range.elementName,
                                            style = MaterialTheme.typography.labelSmall,
                                            fontFamily = FontFamily.Monospace,
                                            color = MaterialTheme.colorScheme.onSurfaceVariant,
                                            fontSize = 10.sp
                                        )
                                    }
                                }
                            }
                        }

                        androidx.compose.material3.HorizontalDivider(
                            modifier = Modifier.padding(bottom = 8.dp),
                            color = MaterialTheme.colorScheme.outlineVariant.copy(alpha = 0.5f)
                        )
                    }

                    fileResult.issues.forEach { issue ->
                        LintIssueRow(issue = issue)
                    }
                    Spacer(modifier = Modifier.height(8.dp))
                }
            }
        }
    }
}

/**
 * Individual lint issue row
 */
@Composable
fun LintIssueRow(issue: LintIssue, modifier: Modifier = Modifier) {
    Row(
        modifier = modifier
            .fillMaxWidth()
            .padding(vertical = 4.dp),
        horizontalArrangement = Arrangement.spacedBy(8.dp)
    ) {
        // Severity icon
        val (severityColor, severityIcon) = when (issue.severity) {
            cc.unitmesh.agent.linter.LintSeverity.ERROR ->  AutoDevColors.Red.c600 to AutoDevComposeIcons.Error
            cc.unitmesh.agent.linter.LintSeverity.WARNING -> AutoDevColors.Amber.c600 to AutoDevComposeIcons.Warning
            cc.unitmesh.agent.linter.LintSeverity.INFO -> AutoDevColors.Blue.c600 to AutoDevComposeIcons.Info
        }

        Icon(
            imageVector = severityIcon,
            contentDescription = issue.severity.name,
            tint = severityColor,
            modifier = Modifier.size(14.dp)
        )

        Column(modifier = Modifier.weight(1f)) {
            Row(horizontalArrangement = Arrangement.spacedBy(4.dp)) {
                Text(
                    text = "Line ${issue.line}:${issue.column}",
                    style = MaterialTheme.typography.labelSmall,
                    fontFamily = FontFamily.Companion.Monospace,
                    color = MaterialTheme.colorScheme.onSurfaceVariant
                )
                issue.rule?.let { rule ->
                    Text(
                        text = "[$rule]",
                        style = MaterialTheme.typography.labelSmall,
                        fontFamily = FontFamily.Companion.Monospace,
                        color = AutoDevColors.Indigo.c600
                    )
                }
            }
            Text(
                text = issue.message,
                style = MaterialTheme.typography.bodySmall,
                color = MaterialTheme.colorScheme.onSurface
            )
            issue.suggestion?.let { suggestion ->
                Text(
                    text = "💡 $suggestion",
                    style = MaterialTheme.typography.bodySmall,
                    color = AutoDevColors.Green.c600,
                    modifier = Modifier.padding(top = 2.dp)
                )
            }
        }
    }
}

@Composable
fun IssueBadge(
    count: Int,
    color: Color,
    label: String,
    modifier: Modifier = Modifier
) {
    Surface(
        color = color.copy(alpha = 0.15f),
        shape = RoundedCornerShape(10.dp),
        modifier = modifier
    ) {
        Row(
            modifier = Modifier.padding(horizontal = 6.dp, vertical = 2.dp),
            horizontalArrangement = Arrangement.spacedBy(3.dp),
            verticalAlignment = Alignment.Companion.CenterVertically
        ) {
            Text(
                text = label,
                style = MaterialTheme.typography.labelSmall,
                fontWeight = FontWeight.Companion.Bold,
                color = color,
                fontSize = 10.sp
            )
            Text(
                text = count.toString(),
                style = MaterialTheme.typography.labelSmall,
                fontWeight = FontWeight.Companion.Bold,
                color = color,
                fontSize = 10.sp
            )
        }
    }
}