<?php

namespace App\Services;

use Illuminate\Support\Facades\Log;
use App\Models\StudentKnowledgeMastery;
use App\Models\MistakeRecord;
use App\Models\KnowledgePoint;

class ExamTypeStrategy
{
    protected QuestionExpansionService $questionExpansionService;

    public function __construct(QuestionExpansionService $questionExpansionService)
    {
        $this->questionExpansionService = $questionExpansionService;
    }

    /**
     * 根据组卷类型构建参数
     */
    public function buildParams(array $baseParams, string $examType): array
    {
        Log::info('ExamTypeStrategy: 构建组卷参数', [
            'exam_type' => $examType,
            'base_params_keys' => array_keys($baseParams)
        ]);

        return match($examType) {
            'diagnostic' => $this->buildDiagnosticParams($baseParams),
            'practice' => $this->buildPracticeParams($baseParams),
            'mistake' => $this->buildMistakeParams($baseParams),
            'textbook' => $this->buildTextbookParams($baseParams),
            'knowledge' => $this->buildKnowledgeParams($baseParams),
            default => $this->buildGeneralParams($baseParams)
        };
    }

    /**
     * 通用智能出卷（原有行为）
     */
    private function buildGeneralParams(array $params): array
    {
        Log::info('ExamTypeStrategy: 通用智能出卷参数', $params);

        // 返回原始参数，不做特殊处理
        return $params;
    }

    /**
     * 摸底测试：评估当前水平
     */
    private function buildDiagnosticParams(array $params): array
    {
        Log::info('ExamTypeStrategy: 构建摸底测试参数', $params);

        // 摸底测试：平衡所有难度，覆盖多个知识点
        $enhanced = array_merge($params, [
            // 难度配比：相对平衡，基础题稍多
            'difficulty_ratio' => [
                '基础' => 40,
                '中等' => 40,
                '拔高' => 20,
            ],
            // 题型配比：选择题多一些，便于快速评估
            'question_type_ratio' => [
                '选择题' => 50,
                '填空题' => 25,
                '解答题' => 25,
            ],
            // 确保覆盖多个知识点
            'kp_codes' => $this->expandKpCodesForDiagnostic($params['kp_codes'] ?? []),
            // 摸底测试名称
            'paper_name' => $params['paper_name'] ?? ('摸底测试_' . now()->format('Ymd_His')),
        ]);

        Log::info('ExamTypeStrategy: 摸底测试参数构建完成', [
            'difficulty_ratio' => $enhanced['difficulty_ratio'],
            'question_type_ratio' => $enhanced['question_type_ratio'],
            'kp_codes_count' => count($enhanced['kp_codes'])
        ]);

        return $enhanced;
    }

    /**
     * 错题：针对薄弱点强化
     * 使用 QuestionExpansionService 按优先级扩展题目
     */
    private function buildMistakeParams(array $params): array
    {
        Log::info('ExamTypeStrategy: 构建错题参数', $params);

        $studentId = $params['student_id'] ?? null;
        $totalQuestions = $params['total_questions'] ?? 20;
        $mistakeOptions = $params['mistake_options'] ?? [];
        $weaknessThreshold = $mistakeOptions['weakness_threshold'] ?? 0.7;
        $intensity = $mistakeOptions['intensity'] ?? 'medium';
        $focusWeaknesses = $mistakeOptions['focus_weaknesses'] ?? true;

        // 根据强度调整难度配比
        $difficultyRatio = match($intensity) {
            'low' => [
                '基础' => 60,
                '中等' => 35,
                '拔高' => 5,
            ],
            'medium' => [
                '基础' => 45,
                '中等' => 40,
                '拔高' => 15,
            ],
            'high' => [
                '基础' => 30,
                '中等' => 45,
                '拔高' => 25,
            ],
            default => [
                '基础' => 45,
                '中等' => 40,
                '拔高' => 15,
            ]
        };

        // 获取学生薄弱点
        $weaknessFilter = [];
        if ($studentId && $focusWeaknesses) {
            $weaknessFilter = $this->getStudentWeaknesses($studentId, $weaknessThreshold);
            Log::info('ExamTypeStrategy: 获取到学生薄弱点', [
                'student_id' => $studentId,
                'weakness_threshold' => $weaknessThreshold,
                'weakness_count' => count($weaknessFilter)
            ]);
        }

        // 使用 QuestionExpansionService 按优先级扩展题目
        $questionStrategy = $this->questionExpansionService->expandQuestions(
            $params,
            $studentId,
            $weaknessFilter,
            $totalQuestions
        );

        // 获取错题知识点
        $mistakeKnowledgePoints = [];
        if ($studentId && !empty($questionStrategy['mistake_question_ids'])) {
            $mistakeRecords = MistakeRecord::forStudent($studentId)
                ->whereIn('question_id', $questionStrategy['mistake_question_ids'])
                ->select(['knowledge_point'])
                ->get();
            $mistakeKnowledgePoints = array_unique(array_filter($mistakeRecords->pluck('knowledge_point')->toArray()));
            Log::info('ExamTypeStrategy: 获取错题知识点', [
                'knowledge_points' => $mistakeKnowledgePoints
            ]);
        }

        // 获取扩展统计
        $expansionStats = $this->questionExpansionService->getExpansionStats($questionStrategy);

        $enhanced = array_merge($params, [
            'difficulty_ratio' => $difficultyRatio,
            'mistake_ids' => $questionStrategy['mistake_ids'],
            'mistake_question_ids' => $questionStrategy['mistake_question_ids'],
            // 错题回顾的知识点优先级
            'priority_knowledge_points' => array_merge(
                array_values($mistakeKnowledgePoints), // 错题知识点优先
                array_column($weaknessFilter, 'kp_code') // 然后是薄弱点
            ),
            // 错题回顾更注重针对性
            'question_type_ratio' => [
                '选择题' => 35,
                '填空题' => 30,
                '解答题' => 35,
            ],
            'paper_name' => $params['paper_name'] ?? ('错题_' . now()->format('Ymd_His')),
            // 标记这是错题，用于后续处理
            'is_mistake_exam' => true,
            'weakness_filter' => $weaknessFilter,
            // 题目扩展统计
            'question_expansion_stats' => $expansionStats
        ]);

        Log::info('ExamTypeStrategy: 错题参数构建完成', [
            'intensity' => $intensity,
            'total_questions_needed' => $totalQuestions,
            'mistake_question_ids_count' => count($enhanced['mistake_question_ids']),
            'priority_knowledge_points_count' => count($enhanced['priority_knowledge_points']),
            'question_expansion_stats' => $enhanced['question_expansion_stats'],
            'weakness_count' => count($weaknessFilter)
        ]);

        return $enhanced;
    }

    /**
     * 专项练习：针对特定技能或知识点练习
     */
    private function buildPracticeParams(array $params): array
    {
        Log::info('ExamTypeStrategy: 构建专项练习参数', $params);

        $studentId = $params['student_id'] ?? null;
        $practiceOptions = $params['practice_options'] ?? [];
        $weaknessThreshold = $practiceOptions['weakness_threshold'] ?? 0.7;
        $intensity = $practiceOptions['intensity'] ?? 'medium';
        $focusWeaknesses = $practiceOptions['focus_weaknesses'] ?? true;

        // 根据强度调整难度配比
        $difficultyRatio = match($intensity) {
            'low' => [
                '基础' => 60,
                '中等' => 35,
                '拔高' => 5,
            ],
            'medium' => [
                '基础' => 45,
                '中等' => 40,
                '拔高' => 15,
            ],
            'high' => [
                '基础' => 30,
                '中等' => 45,
                '拔高' => 25,
            ],
            default => [
                '基础' => 45,
                '中等' => 40,
                '拔高' => 15,
            ]
        };

        // 获取学生薄弱点
        $weaknessFilter = [];
        if ($studentId && $focusWeaknesses) {
            $weaknessFilter = $this->getStudentWeaknesses($studentId, $weaknessThreshold);
            Log::info('ExamTypeStrategy: 获取到学生薄弱点', [
                'student_id' => $studentId,
                'weakness_threshold' => $weaknessThreshold,
                'weakness_count' => count($weaknessFilter)
            ]);
        }

        // 优先使用薄弱点知识点，如果没有则使用用户选择的知识点
        $kpCodes = $params['kp_codes'] ?? [];
        if ($studentId && empty($kpCodes) && !empty($weaknessFilter)) {
            $kpCodes = array_column($weaknessFilter, 'kp_code');
            Log::info('ExamTypeStrategy: 使用薄弱点作为知识点', [
                'kp_codes' => $kpCodes
            ]);
        }

        $enhanced = array_merge($params, [
            'difficulty_ratio' => $difficultyRatio,
            'kp_codes' => $kpCodes,
            // 专项练习更注重题型覆盖
            'question_type_ratio' => [
                '选择题' => 40,
                '填空题' => 30,
                '解答题' => 30,
            ],
            'paper_name' => $params['paper_name'] ?? ('专项练习_' . now()->format('Ymd_His')),
            // 标记这是专项练习，用于后续处理
            'is_practice_exam' => true,
            'weakness_filter' => $weaknessFilter,
        ]);

        Log::info('ExamTypeStrategy: 专项练习参数构建完成', [
            'intensity' => $intensity,
            'difficulty_ratio' => $enhanced['difficulty_ratio'],
            'kp_codes_count' => count($enhanced['kp_codes']),
            'weakness_count' => count($weaknessFilter)
        ]);

        return $enhanced;
    }

    /**
     * 教材同步：按教材章节出题
     */
    private function buildTextbookParams(array $params): array
    {
        Log::info('ExamTypeStrategy: 构建教材同步参数', $params);

        // 教材同步：按章节顺序，难度递增
        $textbookOptions = $params['textbook_options'] ?? [];

        $enhanced = array_merge($params, [
            // 教材同步：基础和中等题为主
            'difficulty_ratio' => [
                '基础' => 50,
                '中等' => 40,
                '拔高' => 10,
            ],
            'question_type_ratio' => [
                '选择题' => 40,
                '填空题' => 30,
                '解答题' => 30,
            ],
            'paper_name' => $params['paper_name'] ?? ('教材同步_' . now()->format('Ymd_His')),
            'textbook_options' => $textbookOptions,
        ]);

        return $enhanced;
    }

    /**
     * 知识点专练：单个或少量知识点深练
     */
    private function buildKnowledgeParams(array $params): array
    {
        Log::info('ExamTypeStrategy: 构建知识点专练参数', $params);

        // 知识点专练：深度挖掘，多角度考查
        $knowledgeOptions = $params['knowledge_options'] ?? [];

        $enhanced = array_merge($params, [
            // 知识点专练：难度分布更均匀
            'difficulty_ratio' => [
                '基础' => 35,
                '中等' => 45,
                '拔高' => 20,
            ],
            'question_type_ratio' => [
                '选择题' => 30,
                '填空题' => 35,
                '解答题' => 35,
            ],
            'paper_name' => $params['paper_name'] ?? ('知识点专练_' . now()->format('Ymd_His')),
            'knowledge_options' => $knowledgeOptions,
        ]);

        return $enhanced;
    }

    /**
     * 为摸底测试扩展知识点（确保覆盖全面）
     */
    private function expandKpCodesForDiagnostic(array $kpCodes): array
    {
        if (!empty($kpCodes)) {
            return $kpCodes;
        }

        // 如果没有指定知识点，返回一些通用的数学知识点
        return [
            '一元二次方程',
            '二次函数',
            '旋转',
            '圆',
            '概率初步',
        ];
    }

    /**
     * 获取学生薄弱点
     */
    private function getStudentWeaknesses(string $studentId, float $threshold): array
    {
        try {
            // 使用 StudentKnowledgeMastery 模型获取掌握度低于阈值的知识点
            $weaknessRecords = StudentKnowledgeMastery::forStudent($studentId)
                ->weaknesses($threshold)
                ->orderByMastery('asc')
                ->limit(20)
                ->with('knowledgePoint') // 预加载知识点信息
                ->get();

            // 转换为统一格式
            return $weaknessRecords->map(function ($record) {
                return [
                    'kp_code' => $record->kp_code,
                    'kp_name' => $record->knowledgePoint->name ?? $record->kp_code,
                    'mastery' => (float) ($record->mastery_level ?? 0),
                    'attempts' => (int) ($record->total_attempts ?? 0),
                    'correct' => (int) ($record->correct_attempts ?? 0),
                    'incorrect' => (int) ($record->incorrect_attempts ?? 0),
                    'confidence' => (float) ($record->confidence_level ?? 0),
                    'trend' => $record->mastery_trend ?? 'stable',
                ];
            })->toArray();

        } catch (\Exception $e) {
            Log::error('ExamTypeStrategy: 获取学生薄弱点失败', [
                'student_id' => $studentId,
                'threshold' => $threshold,
                'error' => $e->getMessage()
            ]);

            return [];
        }
    }
}