<?php

namespace App\Console\Commands;

use App\Models\Question;
use App\Services\Analytics\QuestionDifficultyCalibrationAnalyzer;
use Carbon\Carbon;
use Illuminate\Console\Command;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\File;

class AnalyzeQuestionDifficultyCalibrationCommand extends Command
{
    protected $signature = 'questions:difficulty-calibration-report
                            {--min-attempts=5 : 每题至少多少次已判分作答才纳入}
                            {--since= : 仅统计该日期之后（含），Y-m-d}
                            {--no-mistakes : 不合并 mistake_records}
                            {--calibration-min-attempts=10 : 动态调整生效的最小有效样本（硬约束）}
                            {--alpha=0.2 : 平滑系数（硬约束）}
                            {--max-step=0.03 : 单次调整最大幅度（硬约束）}
                            {--half-life-days=30 : 时间衰减半衰期（天，硬约束）}
                            {--student= : 只统计该 student_id（papers.student_id）下的作答}
                            {--question-bank-id= : 只分析该题库主键 id（questions.id）}
                            {--question-code= : 只分析该题编码（questions.question_code）}
                            {--limit=80 : 终端打印多少行具体题目；0 表示全部}
                            {--sort=attempts : 排序：attempts|gap_desc|gap_asc（gap=实测错误率−题库难度0～1）}
                            {--with-stem : 为每行截取题干前 60 字（仅建议与 --limit 联用）}
                            {--with-aggregate : 额外打印 Pearson、分箱等汇总}
                            {--json= : 完整 JSON 路径}
                            {--csv= : per_question CSV 路径}';

    protected $description = '按「每一道做过的题」输出具体次数、对错、题库难度等（paper_questions 聚合）';

    public function handle(QuestionDifficultyCalibrationAnalyzer $analyzer): int
    {
        $since = $this->option('since')
            ? Carbon::parse((string) $this->option('since'))->startOfDay()
            : null;

        $qbId = $this->option('question-bank-id');
        $minAttempts = (int) $this->option('min-attempts');
        if ($qbId !== null && $qbId !== '' && $minAttempts === 5) {
            $minAttempts = 1;
        }

        $report = $analyzer->run([
            'min_attempts' => $minAttempts,
            'since' => $since,
            'include_mistakes' => ! $this->option('no-mistakes'),
            'calibration_min_attempts' => (int) $this->option('calibration-min-attempts'),
            'alpha' => (float) $this->option('alpha'),
            'max_step' => (float) $this->option('max-step'),
            'half_life_days' => (int) $this->option('half-life-days'),
            'student_id' => $this->option('student'),
            'question_bank_id' => $qbId !== null && $qbId !== '' ? (int) $qbId : null,
            'question_code' => $this->option('question-code') ? (string) $this->option('question-code') : null,
        ]);

        if (! ($report['ok'] ?? false)) {
            $this->error($report['error'] ?? '分析失败');

            return self::FAILURE;
        }

        $rows = collect($report['per_question'] ?? []);

        $meta = $report['meta'] ?? [];
        $this->line('筛选条件: min_attempts='.($meta['min_attempts'] ?? '')
            .($meta['since'] ? ' since='.$meta['since'] : '')
            .($meta['student_id'] ? ' student_id='.$meta['student_id'] : '')
            .($meta['question_bank_id'] ? ' question_bank_id='.$meta['question_bank_id'] : ''));
        $constraints = $meta['calibration_constraints'] ?? [];
        if ($constraints !== []) {
            $this->line(
                '动态约束: stratified_by='.$constraints['stratified_by']
                .' min='.$constraints['min_attempts']
                .' alpha='.$constraints['alpha']
                .' max_step='.$constraints['max_step']
                .' half_life_days='.$constraints['time_decay_half_life_days']
            );
        }
        $this->line('命中题数（聚合行数）: '.($meta['question_rows'] ?? $rows->count()));
        $this->newLine();

        $sort = (string) $this->option('sort');
        $rows = match ($sort) {
            'gap_desc' => $rows->sortByDesc(fn ($r) => abs((float) ($r['calibration_gap'] ?? 0)))->values(),
            'gap_asc' => $rows->sortBy(fn ($r) => abs((float) ($r['calibration_gap'] ?? 0)))->values(),
            default => $rows->sortByDesc('attempts')->values(),
        };

        $withStem = (bool) $this->option('with-stem');
        $stemById = [];
        if ($withStem && $rows->isNotEmpty()) {
            $ids = $rows->pluck('question_bank_id')->unique()->filter()->all();
            $stemById = DB::table('questions')
                ->whereIn('id', $ids)
                ->pluck('stem', 'id')
                ->all();
        }

        $limit = (int) $this->option('limit');
        $slice = $limit === 0 ? $rows : $rows->take($limit);

        $tableRows = $slice->map(function (array $r) use ($withStem, $stemById) {
            $norm = $r['bank_difficulty_normalized'];
            $emp = $r['empirical_error_rate'];
            $line = [
                (string) ($r['question_bank_id'] ?? ''),
                (string) ($r['question_code'] ?? ''),
                (string) ($r['attempts'] ?? ''),
                (string) ($r['correct_count'] ?? ''),
                (string) ($r['wrong_count'] ?? ''),
                $r['accuracy'] !== null ? (string) $r['accuracy'] : '',
                $r['bank_difficulty'] !== null ? (string) $r['bank_difficulty'] : '',
                $norm !== null ? (string) $norm : '',
                $r['avg_paper_question_difficulty'] !== null ? (string) round((float) $r['avg_paper_question_difficulty'], 4) : '',
                $emp !== null ? (string) round((float) $emp, 4) : '',
                $r['calibration_gap'] !== null ? (string) $r['calibration_gap'] : '',
                isset($r['calibration_weighted_error_rate']) ? (string) $r['calibration_weighted_error_rate'] : '',
                isset($r['calibration_effective_attempts']) ? (string) $r['calibration_effective_attempts'] : '',
                (string) (($r['calibration_recommendation']['action'] ?? 'hold')),
                isset($r['calibration_recommendation']['delta']) ? (string) $r['calibration_recommendation']['delta'] : '',
                isset($r['calibration_recommendation']['suggested_difficulty']) ? (string) $r['calibration_recommendation']['suggested_difficulty'] : '',
                (string) ($r['mistake_records_count'] ?? '0'),
            ];
            if ($withStem) {
                $id = (int) ($r['question_bank_id'] ?? 0);
                $raw = $stemById[$id] ?? '';
                $text = $raw !== '' ? mb_substr(trim(strip_tags($raw)), 0, 60) : '';
                $line[] = $text;
            }

            return $line;
        })->all();

        $headers = [
            '题库id',
            'question_code',
            '作答次数',
            '对',
            '错',
            '正确率',
            '题库difficulty(原值)',
            '题库难度(0~1)',
            '卷面难度均值',
            '实测错误率',
            '标定-实测差(gap)',
            '分层时衰错误率',
            '有效样本(时衰)',
            '建议动作',
            '建议delta',
            '建议新难度',
            '错题本行数',
        ];
        if ($withStem) {
            $headers[] = '题干前60字';
        }

        $this->info('【每一道做过且已判分的题】——以下为聚合结果（同一题库 id 跨所有相关试卷合并）');
        $this->table($headers, $tableRows);
        if ($limit > 0 && $rows->count() > $limit) {
            $this->comment('仅显示前 '.$limit.' 行，共 '.$rows->count().' 行；加 --limit=0 可输出全部（建议配合 --csv）。');
        }
        $this->newLine();

        $qb = $meta['question_bank_id'] ?? null;
        if ($qb !== null) {
            $q = Question::query()->find($qb);
            if ($q) {
                $this->info('【本题题干节选】question_bank_id='.$qb);
                $this->line(mb_substr(trim(strip_tags((string) $q->stem)), 0, 400));
                $this->newLine();
            }
        }

        if ($this->option('with-aggregate')) {
            $s = $report['summary'] ?? [];
            $this->line('Pearson(题库0~1难度 vs 实测错误率): '.json_encode($s['pearson_bank_difficulty_vs_empirical_error_rate'] ?? null));
            $this->line($s['interpretation'] ?? '');
            $this->line('Pearson(学案档位 vs 单次是否错): '.json_encode($s['pearson_paper_difficulty_category_vs_incorrect'] ?? null));
            $paper = $report['paper_difficulty_category_vs_incorrect_rate'] ?? [];
            $this->table(
                ['学案档位(0-4)', '条数', '错误率'],
                collect($paper['by_category'] ?? [])->map(fn ($r) => [
                    $r['difficulty_category_numeric'] ?? 'unknown',
                    $r['n'],
                    $r['incorrect_rate'],
                ])->all()
            );
            $this->table(
                ['bin_min', 'bin_max', '题数', '总作答', '平均正确率'],
                collect($report['bins_by_bank_difficulty'] ?? [])->map(fn ($b) => [
                    $b['min'], $b['max'], $b['n_questions'], $b['total_attempts'], $b['mean_accuracy'],
                ])->all()
            );
            $this->newLine();
        }

        $jsonPath = $this->option('json');
        if ($jsonPath) {
            File::put($jsonPath, json_encode($report, JSON_UNESCAPED_UNICODE | JSON_PRETTY_PRINT));
            $this->info('JSON: '.$jsonPath);
        }

        $csvPath = $this->option('csv');
        if ($csvPath) {
            $this->writeCsv($csvPath, $report['per_question'] ?? []);
            $this->info('CSV: '.$csvPath);
        }

        return self::SUCCESS;
    }

    /**
     * @param  list<array<string, mixed>>  $rows
     */
    private function writeCsv(string $path, array $rows): void
    {
        $fh = fopen($path, 'wb');
        if ($fh === false) {
            $this->error('无法写入 CSV');

            return;
        }
        $headers = [
            'question_bank_id',
            'question_code',
            'attempts',
            'correct_count',
            'wrong_count',
            'accuracy',
            'bank_difficulty',
            'bank_difficulty_normalized',
            'avg_paper_question_difficulty',
            'empirical_error_rate',
            'calibration_gap',
            'calibration_weighted_error_rate',
            'calibration_effective_attempts',
            'recommended_action',
            'recommended_delta',
            'suggested_difficulty',
            'mistake_records_count',
        ];
        fputcsv($fh, $headers);
        foreach ($rows as $r) {
            fputcsv($fh, [
                $r['question_bank_id'] ?? '',
                $r['question_code'] ?? '',
                $r['attempts'] ?? '',
                $r['correct_count'] ?? '',
                $r['wrong_count'] ?? '',
                $r['accuracy'] ?? '',
                $r['bank_difficulty'] ?? '',
                $r['bank_difficulty_normalized'] ?? '',
                $r['avg_paper_question_difficulty'] ?? '',
                $r['empirical_error_rate'] ?? '',
                $r['calibration_gap'] ?? '',
                $r['calibration_weighted_error_rate'] ?? '',
                $r['calibration_effective_attempts'] ?? '',
                $r['calibration_recommendation']['action'] ?? '',
                $r['calibration_recommendation']['delta'] ?? '',
                $r['calibration_recommendation']['suggested_difficulty'] ?? '',
                $r['mistake_records_count'] ?? '',
            ]);
        }
        fclose($fh);
    }
}