<?php

declare(strict_types=1);

/**
 * Synchronizes Grade 10 curriculum tree from manifest.accepted.json into live manifest.json
 * and copies all 369 candidate lesson files into storage/curriculum/grade_10/.
 *
 * Usage:
 *   php backend/scripts/sync_grade10_manifest.php [--apply]
 */

$apply = in_array('--apply', $argv, true);
$projectRoot = dirname(__DIR__, 2);
$curriculumRoot = $projectRoot . '/backend/storage/curriculum';
$incomingRoot = $curriculumRoot . '/_incoming';
$acceptedManifestPath = $incomingRoot . '/grade_10/manifest.accepted.json';
$liveManifestPath = $curriculumRoot . '/manifest.json';

if (!file_exists($acceptedManifestPath)) {
    fwrite(STDERR, "Error: manifest.accepted.json not found at {$acceptedManifestPath}\n");
    exit(1);
}

$accepted = json_decode(file_get_contents($acceptedManifestPath), true);
if (!is_array($accepted) || empty($accepted['lessons'])) {
    fwrite(STDERR, "Error: invalid or empty manifest.accepted.json\n");
    exit(1);
}

$live = file_exists($liveManifestPath) ? json_decode(file_get_contents($liveManifestPath), true) : [];
if (!is_array($live)) {
    $live = [];
}

$subjectNames = [
    'math_10' => 'الرياضيات (Mathematics 10)',
    'english_10' => 'اللغة الإنجليزية (English — High Note 10)',
    'physics_10' => 'الفيزياء (Physics 10)',
    'chemistry_10' => 'الكيمياء (Chemistry 10)',
    'biology_10' => 'العلوم الحياتية (Biology 10)',
    'earth_sciences_10' => 'علوم الأرض والبيئة (Earth Sciences 10)',
    'arabic_10' => 'اللغة العربية (Arabic 10)',
    'islamic_10' => 'التربية الإسلامية (Islamic Studies 10)',
    'history_10' => 'تاريخ الأردن (Jordan History 10)',
    'geography_10' => 'الجغرافيا (Geography 10)',
    'civics_10' => 'التربية الوطنية والمدنية (Civics 10)',
    'financial_10' => 'التربية المالية (Financial Literacy 10)',
    'digital_skills_10' => 'المهارات الرقمية (Digital Skills 10)',
];

$unitNamesMap = [
    'unit_01' => 'الوحدة الأولى',
    'unit_02' => 'الوحدة الثانية',
    'unit_03' => 'الوحدة الثالثة',
    'unit_04' => 'الوحدة الرابعة',
    'unit_05' => 'الوحدة الخامسة',
    'unit_06' => 'الوحدة السادسة',
    'unit_07' => 'الوحدة السابعة',
    'unit_08' => 'الوحدة الثامنة',
    'unit_09' => 'الوحدة التاسعة',
    'unit_10' => 'الوحدة العاشرة',
    'unit_11' => 'الوحدة الحادية عشرة',
    'unit_12' => 'الوحدة الثانية عشرة',
];

$semesterNamesMap = [
    'semester_1' => 'الفصل الدراسي الأول',
    'semester_2' => 'الفصل الدراسي الثاني',
];

if (!isset($live['grade_10'])) {
    $live['grade_10'] = [
        'name' => 'الصف العاشر الأساسي (Grade 10)',
        'curriculum_framework' => 'Jordan Ministry of Education (MOE) 2026',
        'subjects' => [],
    ];
}

$copiedFiles = 0;
$tree = &$live['grade_10']['subjects'];

foreach ($accepted['lessons'] as $lesson) {
    $subKey = (string)$lesson['subject_key'];
    $semKey = (string)$lesson['semester_key'];
    $unitKey = (string)$lesson['unit_key'];
    $fileRel = (string)$lesson['file']; // e.g. grade_10/chemistry_10/semester_1/unit_01/lesson_01.md

    // Copy file to live storage if applying
    if ($apply) {
        $sourceFile = $incomingRoot . '/' . $fileRel;
        $destFile = $curriculumRoot . '/' . $fileRel;
        if (file_exists($sourceFile)) {
            $destDir = dirname($destFile);
            if (!is_dir($destDir)) {
                mkdir($destDir, 0755, true);
            }
            if (!file_exists($destFile) || hash_file('sha256', $sourceFile) !== hash_file('sha256', $destFile)) {
                copy($sourceFile, $destFile);
                $copiedFiles++;
            }
        }
    }

    // Ensure subject node
    if (!isset($tree[$subKey])) {
        $tree[$subKey] = [
            'name' => $subjectNames[$subKey] ?? $subKey,
            'semesters' => [],
            'resources' => [
                'textbooks' => ['items' => []],
                'worksheets' => ['items' => []],
            ],
        ];
    }

    // Ensure semester node
    if (!isset($tree[$subKey]['semesters'][$semKey])) {
        $tree[$subKey]['semesters'][$semKey] = [
            'name' => $semesterNamesMap[$semKey] ?? $semKey,
            'units' => [],
        ];
    }

    // Ensure unit node
    if (!isset($tree[$subKey]['semesters'][$semKey]['units'][$unitKey])) {
        $tree[$subKey]['semesters'][$semKey]['units'][$unitKey] = [
            'name' => $unitNamesMap[$unitKey] ?? $unitKey,
            'lessons' => [],
        ];
    }

    // Check if lesson already exists in unit
    $existingIndex = -1;
    foreach ($tree[$subKey]['semesters'][$semKey]['units'][$unitKey]['lessons'] as $idx => $ex) {
        if (($ex['id'] ?? '') === $lesson['lesson_key'] || ($ex['file'] ?? '') === $fileRel) {
            $existingIndex = $idx;
            break;
        }
    }

    $lessonNode = [
        'id' => $lesson['lesson_key'],
        'title' => $lesson['title'],
        'file' => $fileRel,
        'outcomes' => $lesson['outcomes'] ?? [$lesson['title']],
    ];

    if ($existingIndex >= 0) {
        $tree[$subKey]['semesters'][$semKey]['units'][$unitKey]['lessons'][$existingIndex] = array_merge(
            $tree[$subKey]['semesters'][$semKey]['units'][$unitKey]['lessons'][$existingIndex],
            $lessonNode
        );
    } else {
        $tree[$subKey]['semesters'][$semKey]['units'][$unitKey]['lessons'][] = $lessonNode;
    }
}

// Ensure subjects are ordered logically
$orderedSubjects = [];
foreach (array_keys($subjectNames) as $key) {
    if (isset($tree[$key])) {
        $orderedSubjects[$key] = $tree[$key];
    }
}
foreach ($tree as $k => $v) {
    if (!isset($orderedSubjects[$k])) {
        $orderedSubjects[$k] = $v;
    }
}
$live['grade_10']['subjects'] = $orderedSubjects;

if ($apply) {
    file_put_contents($liveManifestPath, json_encode($live, JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE));
    echo "SUCCESS: manifest.json updated with " . count($orderedSubjects) . " Grade 10 subjects.\n";
    echo "Files copied/verified: {$copiedFiles}\n";
} else {
    echo "DRY RUN: Found " . count($orderedSubjects) . " Grade 10 subjects in accepted manifest:\n";
    foreach ($orderedSubjects as $subKey => $subData) {
        $lessonCount = 0;
        foreach ($subData['semesters'] ?? [] as $sem) {
            foreach ($sem['units'] ?? [] as $u) {
                $lessonCount += count($u['lessons'] ?? []);
            }
        }
        echo "  - {$subKey} ({$subData['name']}): {$lessonCount} lessons\n";
    }
    echo "\nRun with --apply to execute copy and save manifest.json.\n";
}