<?php

namespace App\Http\Controllers\Api;

use App\Http\Controllers\Controller;
use App\Services\TaskManager;
use App\Services\LocalAIAnalysisService;
use App\Services\StudentAnswerAnalysisService;
use App\Services\MasteryCalculator;
use Illuminate\Http\JsonResponse;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Log;

class StudentAnswerAnalysisController extends Controller
{
    public function __construct(
        private readonly TaskManager $taskManager,
        private readonly LocalAIAnalysisService $aiAnalysisService,
        private readonly StudentAnswerAnalysisService $answerAnalysisService,
        private readonly MasteryCalculator $masteryCalculator
    ) {}

    /**
     * 将学案难度分类转换为1-4等级
     */
    private function mapDifficultyCategoryToLevel(string $difficultyCategory): int
    {
        // 移除空格并转为小写比较
        $category = trim($difficultyCategory);

        // 数字直接返回
        if (is_numeric($category)) {
            return max(1, min(4, intval($category)));
        }

        // 中文映射
        return match ($category) {
            '基础', '1' => 1,  // 筑基
            '进阶', '中等', '2' => 2,  // 提分
            '培优', '3' => 3,  // 培优
            '竞赛', '4' => 4,  // 竞赛
            default => 2,  // 默认中级（提分）
        };
    }

    /**
     * 获取试卷的基准难度
     */
    private function getExamBaseDifficulty(string $paperId): int
    {
        try {
            // 从papers表获取difficulty_category
            $paper = DB::table('papers')
                ->where('paper_id', $paperId)
                ->first();

            if (!$paper || empty($paper->difficulty_category)) {
                Log::warning('未找到试卷或难度分类，使用默认难度', [
                    'paper_id' => $paperId,
                    'difficulty_category' => $paper->difficulty_category ?? null,
                ]);
                return 2; // 默认中级（提分）
            }

            $difficultyLevel = $this->mapDifficultyCategoryToLevel($paper->difficulty_category);

            Log::info('获取试卷基准难度', [
                'paper_id' => $paperId,
                'difficulty_category' => $paper->difficulty_category,
                'difficulty_level' => $difficultyLevel,
            ]);

            return $difficultyLevel;

        } catch (\Exception $e) {
            Log::error('获取试卷基准难度失败，使用默认难度', [
                'paper_id' => $paperId,
                'error' => $e->getMessage(),
            ]);
            return 2; // 默认中级（提分）
        }
    }

    /**
     * 更新父节点掌握度（基于子节点平均值）
     */
    private function updateParentMastery(string $studentId, string $kpCode): void
    {
        try {
            // 获取知识点的父节点
            $knowledgePoint = DB::table('knowledge_points')
                ->where('kp_code', $kpCode)
                ->first();

            if (!$knowledgePoint || empty($knowledgePoint->parent_kp_code)) {
                return; // 没有父节点，无需更新
            }

            $parentKpCode = $knowledgePoint->parent_kp_code;

            // 使用MasteryCalculator计算父节点掌握度
            $parentMastery = $this->masteryCalculator->calculateParentMastery($studentId, $parentKpCode);

            // 保存到数据库（作为独立记录）
            DB::table('student_knowledge_mastery')
                ->updateOrInsert(
                    ['student_id' => $studentId, 'kp_code' => $parentKpCode],
                    [
                        'mastery_level' => $parentMastery,
                        'confidence_level' => 0.8, // 父节点置信度默认较高
                        'total_attempts' => DB::raw('COALESCE(total_attempts, 0)'),
                        'correct_attempts' => DB::raw('COALESCE(correct_attempts, 0)'),
                        'mastery_trend' => 'calculated', // 标记为计算得出，非直接测量
                        'last_mastery_update' => now(),
                        'updated_at' => now(),
                        'notes' => '父节点掌握度（基于子节点平均值计算）',
                    ]
                );

            Log::info('父节点掌握度已更新', [
                'student_id' => $studentId,
                'child_kp_code' => $kpCode,
                'parent_kp_code' => $parentKpCode,
                'parent_mastery' => $parentMastery,
            ]);

            // 递归更新更上层的父节点
            $this->updateParentMastery($studentId, $parentKpCode);

        } catch (\Exception $e) {
            Log::error('更新父节点掌握度失败', [
                'student_id' => $studentId,
                'kp_code' => $kpCode,
                'error' => $e->getMessage(),
            ]);
        }
    }

    /**
     * 接收学生作答结果并进行分析
     *
     * @param Request $request
     * @return JsonResponse
     */
    public function submitAnswers(Request $request): JsonResponse
    {
        // 优先从JSON body获取参数，支持向后兼容
        $payload = $request->json()->all();
        if (empty($payload)) {
            $payload = $request->all();
        }

        // student_id类型转换：支持数字和字符串输入
        if (isset($payload['student_id'])) {
            $payload['student_id'] = (string) $payload['student_id'];
        }

        // 【修复】验证参数 - 支持questions数组和is_correct数组格式
        $validator = validator($payload, [
            'paper_id' => 'required|string',
            'student_id' => 'required|string|min:1',
            'questions' => 'required|array',
            'questions.*.question_bank_id' => 'required|integer',
            'questions.*.student_answer' => 'nullable|string',
            'questions.*.is_correct' => 'required|array', // 支持数组格式（多小题/步骤）
            'questions.*.teacher_comment' => 'nullable|string',
        ]);

        if ($validator->fails()) {
            return response()->json([
                'success' => false,
                'message' => '参数错误',
                'errors' => $validator->errors(),
            ], 422);
        }

        $data = $validator->validated();

        try {
            // 使用TaskManager创建异步任务
            $taskId = $this->taskManager->createTask(
                TaskManager::TASK_TYPE_ANALYSIS,
                array_merge($data, ['type' => 'answer_analysis'])
            );

            Log::info('StudentAnswerAnalysisController: 收到作答结果', [
                'task_id' => $taskId,
                'paper_id' => $data['paper_id'],
                'student_id' => $data['student_id'],
                'question_count' => count($data['questions']),
            ]);

            // 触发后台分析处理
            $this->processAnswerAnalysis($taskId, $data);

            return response()->json([
                'success' => true,
                'message' => '作答结果已提交，正在分析中...',
                'data' => [
                    'task_id' => $taskId,
                    'paper_id' => $data['paper_id'],
                    'student_id' => $data['student_id'],
                    'status' => 'processing',
                    'created_at' => now()->toISOString(),
                ],
            ]);

        } catch (\Exception $e) {
            Log::error('提交作答结果失败', [
                'paper_id' => $data['paper_id'] ?? 'unknown',
                'student_id' => $data['student_id'] ?? 'unknown',
                'error' => $e->getMessage(),
            ]);

            return response()->json([
                'success' => false,
                'message' => '提交失败：' . $e->getMessage(),
            ], 500);
        }
    }

    /**
     * 查询分析任务状态
     */
    public function getAnalysisStatus(string $taskId): JsonResponse
    {
        try {
            $task = $this->taskManager->getTaskStatus($taskId);

            if (!$task) {
                return response()->json([
                    'success' => false,
                    'message' => '任务不存在',
                ], 404);
            }

            return response()->json([
                'success' => true,
                'data' => $task,
            ]);

        } catch (\Exception $e) {
            Log::error('查询分析状态失败', [
                'task_id' => $taskId,
                'error' => $e->getMessage(),
            ]);

            return response()->json([
                'success' => false,
                'message' => '查询失败：' . $e->getMessage(),
            ], 500);
        }
    }

    /**
     * 处理作答分析（后台任务）
     */
    private function processAnswerAnalysis(string $taskId, array $data): void
    {
        try {
            $this->taskManager->updateTaskProgress($taskId, 10, '正在处理缺题（默认正确）...');

            // 处理缺题：对于没有提交的题目，默认标记为正确
            $allAnswers = $this->processMissingQuestions($data);

            $this->taskManager->updateTaskProgress($taskId, 30, '正在保存作答记录...');

            // 保存作答记录到数据库（包含缺题）
            $answerRecord = $this->answerAnalysisService->saveAnswerRecord([
                ...$data,
                'answers' => $allAnswers,
            ]);

            $this->taskManager->updateTaskProgress($taskId, 50, '正在分析每道题（包括缺题处理）...');

            // 简化分析：不调用AI，直接使用基础分析
            $questionAnalyses = [];
            foreach ($allAnswers as $answer) {
                $questionAnalyses[] = [
                    'question_id' => $answer['question_id'],
                    'question_number' => $answer['question_number'] ?? null,
                    'kp_code' => $answer['knowledge_point'] ?? null,
                    'student_answer' => $answer['student_answer'] ?? '',
                    'correct_answer' => $answer['correct_answer'] ?? '',
                    'is_correct' => $answer['is_correct'],
                    'score_obtained' => (float) ($answer['score'] ?? 0),
                    'max_score' => (float) ($answer['max_score'] ?? 10),
                    'difficulty' => 0.5,
                    'is_missing' => $answer['is_missing'] ?? false,
                    'model_used' => 'simple-rules',
                ];
            }

            $this->taskManager->updateTaskProgress($taskId, 60, '正在计算掌握度（包括子知识点动态加减和父节点平均）...');

            // 【新算法】使用MasteryCalculator计算掌握度
            // 1. 获取学案基准难度
            $examBaseDifficulty = $this->getExamBaseDifficulty($data['paper_id']);

            // 2. 为每个知识点计算掌握度
            $masteryResults = [];
            foreach ($questionAnalyses as $analysis) {
                if (empty($analysis['kp_code']) || $analysis['is_missing']) {
                    continue; // 跳过没有知识点或缺题的题目
                }

                $kpCode = $analysis['kp_code'];
                if (!isset($masteryResults[$kpCode])) {
                    $masteryResults[$kpCode] = [];
                }
                $masteryResults[$kpCode][] = [
                    'question_id' => $analysis['question_id'],
                    'is_correct' => $analysis['is_correct'],
                    'question_difficulty' => $analysis['difficulty'] ?? 0.5,
                ];
            }

            // 3. 调用MasteryCalculator计算每个知识点的掌握度
            foreach ($masteryResults as $kpCode => $attempts) {
                $this->masteryCalculator->calculateMasteryLevel(
                    $data['student_id'],
                    $kpCode,
                    $attempts,
                    $examBaseDifficulty
                );

                // 4. 计算父节点掌握度（子节点平均值）
                $this->updateParentMastery($data['student_id'], $kpCode);
            }

            $this->taskManager->updateTaskProgress($taskId, 65, '正在保存分析结果...');

            // 准备分析结果数据
            $analysisData = [
                'question_results' => $questionAnalyses,
                'total_questions' => count($questionAnalyses),
                'correct_count' => count(array_filter($questionAnalyses, function($q) { return $q['is_correct'] ?? false; })),
                'wrong_count' => count(array_filter($questionAnalyses, function($q) { return !($q['is_correct'] ?? true); })),
                'model_used' => $questionAnalyses[0]['model_used'] ?? 'unknown',
                'exam_base_difficulty' => $examBaseDifficulty,
            ];

            // 保存分析结果
            $this->answerAnalysisService->saveAnalysisResults($answerRecord, $analysisData, $questionAnalyses);

            $this->taskManager->updateTaskProgress($taskId, 80, '正在生成掌握度快照...');

            // 生成掌握度快照（记录每次分析的掌握度变化）
            $masterySnapshot = $this->answerAnalysisService->createMasterySnapshot(
                $data['student_id'],
                $data['paper_id'],
                $answerRecord['record_id']
            );

            $this->taskManager->updateTaskProgress($taskId, 90, '正在生成学情分析报告...');

            // 生成学情分析报告PDF
            $reportUrl = $this->generateLearningReport($taskId, $data, $answerRecord, $questionAnalyses, $masterySnapshot);

            // 标记任务完成
            $this->taskManager->markTaskCompleted($taskId, [
                'answer_record_id' => $answerRecord['record_id'],
                'analysis_id' => 'analysis_' . uniqid(),
                'mastery_snapshot_id' => $masterySnapshot['snapshot_id'] ?? null,
                'correct_count' => $answerRecord['correct_count'],
                'wrong_count' => $answerRecord['wrong_count'],
                'overall_mastery' => $masterySnapshot['overall_mastery'] ?? null,
                // 'report_url' => $reportUrl, // 临时禁用PDF报告
            ]);

            Log::info('作答分析完成', [
                'task_id' => $taskId,
                'paper_id' => $data['paper_id'],
                'student_id' => $data['student_id'],
                'answer_record_id' => $answerRecord['record_id'],
            ]);

            // 发送回调通知
            $this->taskManager->sendCallback($taskId);

        } catch (\Exception $e) {
            Log::error('作答分析失败', [
                'task_id' => $taskId,
                'paper_id' => $data['paper_id'],
                'student_id' => $data['student_id'],
                'error' => $e->getMessage(),
            ]);

            $this->taskManager->markTaskFailed($taskId, $e->getMessage());
        }
    }

    /**
     * 获取题目文本内容
     */
    private function getQuestionText(string $questionId): string
    {
        try {
            // 这里可以调用 QuestionBankService 获取题目内容
            // 目前返回空字符串，让AI分析基于学生答案进行分析
            return '';
        } catch (\Exception $e) {
            Log::warning('获取题目文本失败', [
                'question_id' => $questionId,
                'error' => $e->getMessage(),
            ]);
            return '';
        }
    }

    /**
     * 处理缺题逻辑：对于没有提交的题目，默认标记为正确
     * 通过paper_id查询paper_question表获取总题数
     */
    private function processMissingQuestions(array $data): array
    {
        // 【修复】处理questions数组格式
        $questions = $data['questions'] ?? [];
        $submittedQuestionIds = array_column($questions, 'question_bank_id');

        // 将questions转换为answers格式以便后续处理
        $answers = [];
        foreach ($questions as $q) {
            // 计算is_correct数组的平均值（判断整体是否正确）
            $isCorrectArray = $q['is_correct'] ?? [];
            $correctSteps = array_sum($isCorrectArray);
            $totalSteps = count($isCorrectArray);
            $isOverallCorrect = $totalSteps > 0 && ($correctSteps / $totalSteps) >= 0.6; // 60%以上步骤正确视为正确

            $answers[] = [
                'question_id' => $q['question_bank_id'],
                'question_number' => null,
                'is_correct' => $isOverallCorrect,
                'student_answer' => $q['student_answer'] ?? '',
                'correct_answer' => '',
                'score' => $correctSteps * 2, // 假设每个步骤2分
                'max_score' => $totalSteps * 2,
                'knowledge_point' => null,
                'question_type' => 'mixed',
                'is_missing' => false,
                'is_correct_array' => $isCorrectArray, // 保留原始数组
                'answer_time' => $data['answer_time'] ?? now(),
            ];
        }

        // 获取缺题列表
        $missingQuestions = $data['missing_questions'] ?? [];

        // 如果没有提供missing_questions，通过paper_id查询paper_question表
        if (empty($missingQuestions)) {
            try {
                // 通过paper_id查询paper_question表获取题目总数
                $totalQuestions = DB::table('paper_questions')
                    ->where('paper_id', $data['paper_id'])
                    ->count();

                Log::info('从paper_question表获取题目总数', [
                    'paper_id' => $data['paper_id'],
                    'total_questions' => $totalQuestions,
                    'submitted_count' => count($submittedQuestionIds),
                ]);

                // 自动生成缺题列表（根据paper_question表的题目编号）
                $allQuestionIds = DB::table('paper_questions')
                    ->where('paper_id', $data['paper_id'])
                    ->pluck('question_id')
                    ->toArray();

                foreach ($allQuestionIds as $questionId) {
                    if (!in_array($questionId, $submittedQuestionIds)) {
                        $missingQuestions[] = $questionId;
                    }
                }

            } catch (\Exception $e) {
                Log::warning('查询paper_question表失败，跳过缺题处理', [
                    'paper_id' => $data['paper_id'],
                    'error' => $e->getMessage(),
                ]);
            }
        }

        // 【修复】处理缺题和学生未作答的题目
        foreach ($missingQuestions as $missingQuestionId) {
            // 使用 Model 获取缺题的详细信息
            $questionDetails = \App\Models\PaperQuestion::where('paper_id', $data['paper_id'])
                ->where('question_id', $missingQuestionId)
                ->first();

            // 获取知识点和分数信息
            $kpCode = $questionDetails?->knowledge_point;
            if (empty($kpCode)) {
                // 【修复】不允许使用默认知识点，必须明确指定
                Log::warning('StudentAnswerAnalysisController: 缺题缺少知识点信息，跳过掌握度计算', [
                    'question_id' => $missingQuestionId,
                    'paper_id' => $data['paper_id'],
                ]);
                continue; // 跳过该缺题，不参与掌握度计算
            }
            $maxScore = floatval($questionDetails?->score ?? 10);
            $questionType = $questionDetails?->question_type ?? 'missing';

            // 【关键】区分缺题和学生未作答：
            // 1. 缺题（API请求中标记的）：按正确计算，100%得分
            // 2. 学生没作答的题目：按30%得分率计算
            $isTrulyMissing = in_array($missingQuestionId, $data['missing_questions'] ?? []);
            $scoreRate = $isTrulyMissing ? 1.0 : 0.3; // 缺题100%，未作答30%
            $score = $maxScore * $scoreRate;
            $isCorrect = ($scoreRate >= 0.6); // 按60%及格线判断

            $answers[] = [
                'question_id' => $missingQuestionId,
                'question_number' => $questionDetails?->question_number ?? $missingQuestionId,
                'is_correct' => $isCorrect,
                'student_answer' => '[缺题]',
                'correct_answer' => '[未作答]',
                'score' => $score,
                'max_score' => $maxScore,
                'knowledge_point' => $kpCode, // 保留知识点信息，参与掌握度计算
                'question_type' => $questionType,
                'is_missing' => $isTrulyMissing, // 真正缺题标记
                'missing_note' => $isTrulyMissing ? '缺题，按100%得分率计算' : '学生未作答，按30%得分率计算掌握度',
                'answer_time' => $data['answer_time'] ?? now(),
            ];
        }

        // 【新增】处理已提交但学生未作答的题目（student_answer为空或null）
        foreach ($answers as &$answer) {
            if (!empty($answer['student_answer']) && $answer['student_answer'] !== '[缺题]') {
                continue; // 已作答的题目跳过
            }

            // 学生未作答的题目，按30%得分率计算
            if (empty($answer['student_answer']) || $answer['student_answer'] === '') {
                $maxScore = floatval($answer['max_score'] ?? 10);
                $scoreRate = 0.3;
                $score = $maxScore * $scoreRate;

                $answer['score'] = $score;
                $answer['is_correct'] = false; // 未作答视为错误
                $answer['missing_note'] = '学生未作答，按30%得分率计算掌握度';
            }
        }

        Log::info('缺题处理完成', [
            'paper_id' => $data['paper_id'],
            'submitted_count' => count($data['questions'] ?? []),
            'missing_count' => count($missingQuestions),
            'total_count' => count($answers),
        ]);

        return $answers;
    }

    /**
     * 生成学情分析报告并异步生成PDF
     */
    private function generateLearningReport(
        string $taskId,
        array $data,
        array $answerRecord,
        array $questionAnalyses,
        ?array $masterySnapshot
    ): ?string {
        try {
            // 构建报告数据
            $reportData = [
                'task_id' => $taskId,
                'paper_id' => $data['paper_id'],
                'student_id' => $data['student_id'],
                'submit_time' => now()->toISOString(),
                'answer_record' => $answerRecord,
                'question_analyses' => $questionAnalyses,
                'mastery_snapshot' => $masterySnapshot,
                'report_type' => 'learning_analysis',
            ];

            // 创建异步任务生成PDF
            $pdfTaskId = $this->taskManager->createTask(
                TaskManager::TASK_TYPE_PDF,
                array_merge($reportData, ['type' => 'learning_report'])
            );

            Log::info('学情分析报告任务已创建', [
                'pdf_task_id' => $pdfTaskId,
                'paper_id' => $data['paper_id'],
                'student_id' => $data['student_id'],
            ]);

            // 返回报告URL（异步生成）
            return route('api.reports.learning', [
                'task_id' => $pdfTaskId,
                'student_id' => $data['student_id'],
            ]);

        } catch (\Exception $e) {
            Log::error('生成学情分析报告失败', [
                'task_id' => $taskId,
                'error' => $e->getMessage(),
            ]);
            return null;
        }
    }

    /**
     * 获取学生学习历史
     */
    public function getStudentLearningHistory(string $studentId): JsonResponse
    {
        try {
            $history = $this->answerAnalysisService->getStudentLearningHistory($studentId);

            return response()->json([
                'success' => true,
                'data' => $history,
            ]);

        } catch (\Exception $e) {
            Log::error('获取学习历史失败', [
                'student_id' => $studentId,
                'error' => $e->getMessage(),
            ]);

            return response()->json([
                'success' => false,
                'message' => '获取失败：' . $e->getMessage(),
            ], 500);
        }
    }
}