<?php

declare(strict_types=1);

/**
 * Publication manager for Grade 10 curriculum bundles and assets.
 *
 * Publishes bundles only after independent lesson and asset approval.
 *
 * Safety rules:
 *  - Default mode is a read-only dry run. It writes nothing unless `--apply` is present.
 *  - All database writes happen inside a single atomic transaction.
 *  - This script never grants academic approval or clears rights.
 *
 * Usage:
 *   php backend/scripts/publish_grade10_bundle.php --status
 *   php backend/scripts/publish_grade10_bundle.php --pilot
 *   php backend/scripts/publish_grade10_bundle.php --pilot --apply
 *   php backend/scripts/publish_grade10_bundle.php --subject=math_10 --unit=unit_01 --apply
 *   php backend/scripts/publish_grade10_bundle.php --all --apply
 *   php backend/scripts/publish_grade10_bundle.php --pilot --revert --apply
 */

$projectRoot = dirname(__DIR__, 2);
require_once dirname(__DIR__) . '/app/bootstrap.php';

use App\Core\Database;

$apply = in_array('--apply', $argv, true);
$statusOnly = in_array('--status', $argv, true);
$isPilot = in_array('--pilot', $argv, true);
$isAll = in_array('--all', $argv, true);
$isRevert = in_array('--revert', $argv, true);
$subjectFilter = null;
$unitFilter = null;

foreach ($argv as $arg) {
    if (str_starts_with($arg, '--subject=')) {
        $subjectFilter = substr($arg, strlen('--subject='));
    }
    if (str_starts_with($arg, '--unit=')) {
        $unitFilter = substr($arg, strlen('--unit='));
    }
}

// 1. Status mode
if ($statusOnly) {
    echo "=== Saqel Grade 10 Publication Status ===\n";
    $lessonStats = Database::select(
        "SELECT source_status, COUNT(*) as count FROM curriculum_lessons WHERE grade_key = 'grade_10' GROUP BY source_status"
    );
    echo "\nCurriculum Lessons (source_status):\n";
    foreach ($lessonStats as $s) {
        echo sprintf("  - %-15s: %d\n", $s['source_status'], $s['count']);
    }

    $bundleStats = Database::select(
        "SELECT pb.status, COUNT(*) as count 
         FROM publication_bundles pb 
         JOIN curriculum_lessons cl ON cl.id = pb.curriculum_lesson_id 
         WHERE cl.grade_key = 'grade_10' 
         GROUP BY pb.status"
    );
    echo "\nPublication Bundles (status):\n";
    foreach ($bundleStats as $s) {
        echo sprintf("  - %-15s: %d\n", $s['status'], $s['count']);
    }

    $assetStats = Database::select(
        "SELECT a.review_status, a.rights_status, COUNT(*) as count 
         FROM content_assets a 
         JOIN publication_bundle_assets pba ON pba.content_asset_id = a.id 
         JOIN publication_bundles pb ON pb.id = pba.publication_bundle_id 
         JOIN curriculum_lessons cl ON cl.id = pb.curriculum_lesson_id 
         WHERE cl.grade_key = 'grade_10' 
         GROUP BY a.review_status, a.rights_status"
    );
    echo "\nContent Assets (review_status / rights_status):\n";
    foreach ($assetStats as $s) {
        echo sprintf("  - %-12s / %-15s: %d\n", $s['review_status'], $s['rights_status'], $s['count']);
    }
    exit(0);
}

// 2. Resolve target lessons
$where = ["grade_key = 'grade_10'"];
$params = [];

if ($isPilot) {
    // 12 key pilot lessons representing Math, Physics, Arabic, and Islamic
    $pilotPaths = [
        // Math 10: Semester 1, Unit 1 (Equations)
        'grade_10/math_10/semester_1/unit_01/lesson_01.md',
        'grade_10/math_10/semester_1/unit_01/lesson_02.md',
        'grade_10/math_10/semester_1/unit_01/lesson_03.md',
        'grade_10/physics_10/semester_1/unit_02/lesson_03.md',
        // Physics 10: Semester 1, Units 1 & 2
        'grade_10/physics_10/semester_1/unit_01/lesson_01.md',
        'grade_10/physics_10/semester_1/unit_01/lesson_02.md',
        'grade_10/physics_10/semester_1/unit_02/lesson_01.md',
        'grade_10/physics_10/semester_1/unit_02/lesson_02.md',
        // Arabic 10: Semester 1, Unit 1
        'grade_10/arabic_10/semester_1/unit_01/lesson_01.md',
        'grade_10/arabic_10/semester_1/unit_01/lesson_02.md',
        // Islamic 10: Semester 1, Unit 1
        'grade_10/islamic_10/semester_1/unit_01/lesson_01.md',
        'grade_10/islamic_10/semester_1/unit_01/lesson_02.md',
    ];
    $placeholders = implode(',', array_fill(0, count($pilotPaths), '?'));
    $where[] = "source_manifest_path IN ($placeholders)";
    $params = array_merge($params, $pilotPaths);
} elseif ($isAll) {
    // All Grade 10 lessons
} else {
    if ($subjectFilter !== null) {
        $where[] = "subject_key = ?";
        $params[] = $subjectFilter;
    }
    if ($unitFilter !== null) {
        $where[] = "unit_key = ?";
        $params[] = $unitFilter;
    }
    if ($subjectFilter === null && $unitFilter === null) {
        fwrite(STDERR, "Error: Specify --pilot, --all, or filter with --subject=... [--unit=...]\n");
        fwrite(STDERR, "Run with --help or --status to view available options.\n");
        exit(1);
    }
}

$sqlWhere = implode(' AND ', $where);
$targetLessons = Database::select(
    "SELECT id, uuid, subject_key, semester_key, unit_key, lesson_key, title, source_manifest_path, source_status
     FROM curriculum_lessons
     WHERE {$sqlWhere}
     ORDER BY subject_key, semester_key, unit_key, lesson_key",
    $params
);

if (empty($targetLessons)) {
    echo "No matching curriculum lessons found for the specified criteria.\n";
    exit(0);
}
if ($isPilot && count($targetLessons) !== 12) {
    fwrite(STDERR, "REFUSE: pilot must contain exactly 12 matching lessons; found " . count($targetLessons) . ".\n");
    exit(2);
}

$lessonIds = array_column($targetLessons, 'id');
$idList = implode(',', array_map('intval', $lessonIds));

// 3. Plan summary
$targetAction = $isRevert ? 'WITHDRAW PUBLISHED BUNDLES' : 'PUBLISH REVIEWED BUNDLES';
echo sprintf("=== Grade 10 Publication Plan (%s) ===\n", $apply ? 'APPLY' : 'DRY-RUN');
echo sprintf("Action: %s\n", $targetAction);
echo sprintf("Matched Lessons: %d\n", count($targetLessons));
echo "\nTarget Lessons:\n";
foreach ($targetLessons as $idx => $l) {
    echo sprintf(" %2d. [%-12s] %-10s / %-10s : %s (Current: %s)\n",
        $idx + 1,
        $l['subject_key'],
        $l['unit_key'],
        $l['lesson_key'],
        $l['title'],
        $l['source_status']
    );
}

function publicationBlockers(array $targetLessons, bool $lock): array
{
    $blockers = [];
    foreach ($targetLessons as $lesson) {
        $id = (int)$lesson['id'];
        $path = $lesson['source_manifest_path'];
        $detail = Database::selectOne(
            'SELECT source_status, reviewed_by, reviewed_at FROM curriculum_lessons WHERE id = ?' . ($lock ? ' FOR UPDATE' : ''),
            [$id]
        );
        if (!$detail || $detail['source_status'] !== 'approved' || empty($detail['reviewed_by']) || empty($detail['reviewed_at'])) {
            $blockers[] = "{$path}: academic approval with reviewer and date is missing";
        }
        $bundles = Database::select(
            'SELECT id, status FROM publication_bundles WHERE curriculum_lesson_id = ?' . ($lock ? ' FOR UPDATE' : ''),
            [$id]
        );
        if (count($bundles) !== 1) {
            $blockers[] = "{$path}: expected exactly one bundle; found " . count($bundles);
            continue;
        }
        $bundle = $bundles[0];
        if (!in_array($bundle['status'], ['review', 'published'], true)) {
            $blockers[] = "{$path}: bundle must be in review before publication";
        }
        $assets = Database::select(
            'SELECT a.id, a.asset_type, a.review_status, a.rights_status, a.source_reference, pba.role
             FROM publication_bundle_assets pba JOIN content_assets a ON a.id = pba.content_asset_id
             WHERE pba.publication_bundle_id = ?' . ($lock ? ' FOR UPDATE' : ''),
            [(int)$bundle['id']]
        );
        if ($assets === []) {
            $blockers[] = "{$path}: bundle has no assets";
        }
        $hasPrimary = false;
        foreach ($assets as $asset) {
            if ($asset['role'] === 'primary_lesson' && $asset['asset_type'] === 'lesson_markdown') $hasPrimary = true;
            if ($asset['review_status'] !== 'approved' || $asset['rights_status'] !== 'cleared' || trim((string)$asset['source_reference']) === '') {
                $blockers[] = "{$path}: asset {$asset['id']} lacks review, rights clearance, or source";
            }
        }
        if (!$hasPrimary) $blockers[] = "{$path}: approved lesson Markdown is missing";
    }
    return $blockers;
}

if (!$apply && !$isRevert) {
    $blockers = publicationBlockers($targetLessons, false);
    foreach ($blockers as $blocker) echo "BLOCKED  {$blocker}\n";
    echo $blockers === [] ? "\n[Ready for reviewed publication; append --apply.]\n" : "\n[Publication blocked; resolve review evidence first.]\n";
    exit($blockers === [] ? 0 : 2);
}
if (!$apply) {
    echo "\n[Dry-run completed. To withdraw bundles, append --apply.]\n";
    exit(0);
}

// 4. Apply changes inside a transaction
$pdo = Database::getConnection();
$pdo->beginTransaction();

try {
    if ($isRevert) {
        // Withdrawal preserves academic decisions, rights records and history.
        Database::query(
            "UPDATE publication_bundles SET status = 'withdrawn', withdrawn_at = CURRENT_TIMESTAMP WHERE curriculum_lesson_id IN ({$idList}) AND status = 'published'"
        );
    } else {
        $blockers = publicationBlockers($targetLessons, true);
        if ($blockers !== []) {
            throw new RuntimeException("Publication blocked:\n" . implode("\n", $blockers));
        }
        Database::query(
            "UPDATE publication_bundles SET status = 'published', published_at = CURRENT_TIMESTAMP WHERE curriculum_lesson_id IN ({$idList}) AND status = 'review'"
        );
    }

    $pdo->commit();
    echo "\n=== SUCCESS: " . ($isRevert ? "Reverted" : "Published") . " " . count($targetLessons) . " lessons successfully. ===\n";
} catch (\Throwable $e) {
    if ($pdo->inTransaction()) {
        $pdo->rollBack();
    }
    fwrite(STDERR, "\nFAILED: Publication transaction rolled back: " . $e->getMessage() . "\n");
    exit(1);
}