<?php
declare(strict_types=1);

function schema_table_has_column(PDO $pdo, string $table, string $column): bool
{
    $stmt = $pdo->prepare(
        'SELECT COUNT(*) FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = :table_name AND COLUMN_NAME = :column_name'
    );
    $stmt->execute([
        ':table_name' => $table,
        ':column_name' => $column,
    ]);

    return (int) $stmt->fetchColumn() > 0;
}

function schema_table_has_index(PDO $pdo, string $table, string $index): bool
{
    $stmt = $pdo->prepare(
        'SELECT COUNT(*) FROM information_schema.STATISTICS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = :table_name AND INDEX_NAME = :index_name'
    );
    $stmt->execute([
        ':table_name' => $table,
        ':index_name' => $index,
    ]);

    return (int) $stmt->fetchColumn() > 0;
}

function schema_table_has_foreign_key(PDO $pdo, string $table, string $constraint): bool
{
    $stmt = $pdo->prepare(
        'SELECT COUNT(*) FROM information_schema.TABLE_CONSTRAINTS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = :table_name AND CONSTRAINT_NAME = :constraint_name AND CONSTRAINT_TYPE = "FOREIGN KEY"'
    );
    $stmt->execute([
        ':table_name' => $table,
        ':constraint_name' => $constraint,
    ]);

    return (int) $stmt->fetchColumn() > 0;
}

function ensure_school_cycle_schema(PDO $pdo): void
{
    static $done = false;
    if ($done) {
        return;
    }

    $migrationPath = __DIR__ . '/../db/migrations/20260416_school_cycles.sql';
    if (is_file($migrationPath)) {
        $sql = file_get_contents($migrationPath);
        if (is_string($sql) && trim($sql) !== '') {
            $pdo->exec($sql);
        }
    }

    $tables = [
        'school_students' => [
            'index' => 'idx_school_students_cycle',
            'foreign_key' => 'fk_school_students_cycle',
        ],
        'school_teachers' => [
            'index' => 'idx_school_teachers_cycle',
            'foreign_key' => 'fk_school_teachers_cycle',
        ],
        'school_assessment_types' => [
            'index' => 'idx_school_assessments_cycle',
            'foreign_key' => 'fk_school_assessments_cycle',
        ],
        'school_attendance_records' => [
            'index' => 'idx_school_attendance_cycle',
            'foreign_key' => 'fk_school_attendance_cycle',
        ],
    ];

    foreach ($tables as $table => $meta) {
        if (!schema_table_has_column($pdo, $table, 'cycle_id')) {
            $pdo->exec('ALTER TABLE ' . $table . ' ADD COLUMN cycle_id INT UNSIGNED NULL AFTER center_application_id');
        }

        if (!schema_table_has_index($pdo, $table, $meta['index'])) {
            $pdo->exec('ALTER TABLE ' . $table . ' ADD INDEX ' . $meta['index'] . ' (cycle_id)');
        }
    }

    ensure_school_cycle_backfill($pdo);

    if (schema_table_has_index($pdo, 'school_students', 'uniq_school_student_code') && !schema_table_has_index($pdo, 'school_students', 'uniq_school_student_cycle_code')) {
        $pdo->exec('ALTER TABLE school_students DROP INDEX uniq_school_student_code');
    }
    if (!schema_table_has_index($pdo, 'school_students', 'uniq_school_student_cycle_code')) {
        $pdo->exec('ALTER TABLE school_students ADD UNIQUE KEY uniq_school_student_cycle_code (center_application_id, cycle_id, student_code)');
    }

    foreach ($tables as $table => $meta) {
        if (!schema_table_has_foreign_key($pdo, $table, $meta['foreign_key'])) {
            $pdo->exec(
                'ALTER TABLE ' . $table . ' ADD CONSTRAINT ' . $meta['foreign_key'] . ' FOREIGN KEY (cycle_id) REFERENCES school_cycles(id) ON DELETE CASCADE'
            );
        }
    }

    $done = true;
}

function ensure_school_cycle_backfill(PDO $pdo): void
{
    $applicationRows = $pdo->query(
        "SELECT * FROM center_applications WHERE status = 'approved' OR id IN (
            SELECT center_application_id FROM school_students
            UNION SELECT center_application_id FROM school_teachers
            UNION SELECT center_application_id FROM school_assessment_types
            UNION SELECT center_application_id FROM school_attendance_records
        ) ORDER BY id ASC"
    )->fetchAll();

    foreach ($applicationRows as $application) {
        $applicationId = (int) ($application['id'] ?? 0);
        if ($applicationId <= 0) {
            continue;
        }

        $cycleId = ensure_default_school_cycle_record($pdo, $application);
        foreach (['school_students', 'school_teachers', 'school_assessment_types', 'school_attendance_records'] as $table) {
            if (!schema_table_has_column($pdo, $table, 'cycle_id')) {
                continue;
            }

            $stmt = $pdo->prepare('UPDATE ' . $table . ' SET cycle_id = :cycle_id WHERE center_application_id = :center_application_id AND cycle_id IS NULL');
            $stmt->execute([
                ':cycle_id' => $cycleId,
                ':center_application_id' => $applicationId,
            ]);
        }
    }
}

function school_cycle_season_map(): array
{
    return [
        'summer' => ['label' => 'Summer', 'label_ar' => 'صيف'],
        'winter' => ['label' => 'Winter', 'label_ar' => 'شتاء'],
    ];
}

function school_cycle_status_map(): array
{
    return [
        'active' => ['label' => 'نشطة', 'class' => 'status-approved'],
        'upcoming' => ['label' => 'قادمة', 'class' => 'status-review'],
        'archived' => ['label' => 'مؤرشفة', 'class' => 'status-muted'],
    ];
}

function school_cycle_status_badge(string $status): string
{
    $map = school_cycle_status_map();
    $meta = $map[$status] ?? ['label' => 'غير محدد', 'class' => 'status-muted'];
    return '<span class="status-badge ' . e($meta['class']) . '">' . e($meta['label']) . '</span>';
}

function school_cycle_season_options(): array
{
    return school_cycle_season_map();
}

function detect_school_cycle_season(?string $date = null): string
{
    $ts = $date ? strtotime($date) : time();
    if ($ts === false) {
        $ts = time();
    }

    $month = (int) date('n', $ts);
    return $month >= 5 && $month <= 9 ? 'summer' : 'winter';
}

function format_school_cycle_name(string $season, int $year): string
{
    $map = school_cycle_season_map();
    $label = $map[$season]['label'] ?? 'Cycle';
    return $label . ' ' . $year;
}

function school_cycle_defaults(?array $application = null): array
{
    $season = detect_school_cycle_season((string) ($application['start_date'] ?? ''));
    $year = (int) date('Y', strtotime((string) ($application['start_date'] ?? 'now')) ?: time());
    $startDate = clean_text((string) ($application['start_date'] ?? date('Y-m-d')), 20);
    $endDate = clean_text((string) ($application['end_date'] ?? date('Y-m-d', strtotime('+90 days'))), 20);

    return [
        'season' => $season,
        'year' => (string) $year,
        'start_date' => $startDate,
        'end_date' => $endDate,
        'status' => 'active',
    ];
}

function validate_school_cycle_input(array $input, ?array $application = null): array
{
    $defaults = school_cycle_defaults($application);
    $data = $defaults;
    $data['season'] = clean_text((string) ($input['season'] ?? $defaults['season']), 20);
    $data['year'] = clean_text((string) ($input['year'] ?? $defaults['year']), 4);
    $data['start_date'] = clean_text((string) ($input['start_date'] ?? $defaults['start_date']), 20);
    $data['end_date'] = clean_text((string) ($input['end_date'] ?? $defaults['end_date']), 20);
    $data['status'] = clean_text((string) ($input['status'] ?? 'active'), 20);

    $errors = [];
    if (!array_key_exists($data['season'], school_cycle_season_options())) {
        $errors['season'] = 'يرجى اختيار موسم صحيح.';
    }

    $year = (int) $data['year'];
    if ((string) $year !== $data['year'] || $year < 2020 || $year > 2100) {
        $errors['year'] = 'يرجى إدخال سنة صحيحة مثل 2026.';
    }

    if ($data['start_date'] === '' || strtotime($data['start_date']) === false) {
        $errors['start_date'] = 'يرجى إدخال تاريخ بداية صحيح.';
    }
    if ($data['end_date'] === '' || strtotime($data['end_date']) === false) {
        $errors['end_date'] = 'يرجى إدخال تاريخ نهاية صحيح.';
    }
    if (!isset($errors['start_date'], $errors['end_date']) && strtotime($data['end_date']) < strtotime($data['start_date'])) {
        $errors['end_date'] = 'تاريخ النهاية يجب أن يكون بعد البداية أو مساوياً لها.';
    }

    if (!in_array($data['status'], ['active', 'upcoming'], true)) {
        $errors['status'] = 'يرجى اختيار حالة تشغيل صحيحة للدورة.';
    }

    return [$data, $errors];
}

function normalize_school_cycle_row(array $row): array
{
    $row['id'] = (int) ($row['id'] ?? 0);
    $row['center_application_id'] = (int) ($row['center_application_id'] ?? 0);
    $row['year'] = (int) ($row['year'] ?? 0);
    $row['cycle_name'] = (string) ($row['cycle_name'] ?? format_school_cycle_name((string) ($row['season'] ?? ''), (int) ($row['year'] ?? 0)));
    $row['status'] = (string) ($row['status'] ?? 'upcoming');
    return $row;
}

function ensure_default_school_cycle_record(PDO $pdo, array $application): int
{
    $applicationId = (int) ($application['id'] ?? 0);
    if ($applicationId <= 0) {
        throw new InvalidArgumentException('Missing application id for school cycle.');
    }

    $stmt = $pdo->prepare('SELECT * FROM school_cycles WHERE center_application_id = :center_application_id ORDER BY FIELD(status, "active", "upcoming", "archived"), start_date DESC, id DESC LIMIT 1');
    $stmt->execute([':center_application_id' => $applicationId]);
    $existing = $stmt->fetch();
    if ($existing) {
        return (int) $existing['id'];
    }

    $season = detect_school_cycle_season((string) ($application['start_date'] ?? ''));
    $year = (int) date('Y', strtotime((string) ($application['start_date'] ?? 'now')) ?: time());
    $startDate = (string) ($application['start_date'] ?? date('Y-m-d'));
    $endDate = (string) ($application['end_date'] ?? $startDate);
    $cycleName = format_school_cycle_name($season, $year);
    $status = ((string) ($application['status'] ?? '') === 'approved') ? 'active' : 'upcoming';

    $insert = $pdo->prepare(
        'INSERT INTO school_cycles (
            center_application_id, season, year, cycle_name, start_date, end_date,
            status, archived_at, created_at, updated_at
        ) VALUES (
            :center_application_id, :season, :year, :cycle_name, :start_date, :end_date,
            :status, NULL, NOW(), NOW()
        )'
    );
    $insert->execute([
        ':center_application_id' => $applicationId,
        ':season' => $season,
        ':year' => $year,
        ':cycle_name' => $cycleName,
        ':start_date' => $startDate,
        ':end_date' => $endDate,
        ':status' => $status,
    ]);

    return (int) $pdo->lastInsertId();
}

function list_school_cycles(int $centerApplicationId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare('SELECT * FROM school_cycles WHERE center_application_id = :center_application_id ORDER BY start_date DESC, id DESC');
    $stmt->execute([':center_application_id' => $centerApplicationId]);
    $rows = $stmt->fetchAll();

    return array_map('normalize_school_cycle_row', $rows);
}

function get_school_cycle(int $centerApplicationId, int $cycleId): ?array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare('SELECT * FROM school_cycles WHERE center_application_id = :center_application_id AND id = :id LIMIT 1');
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':id' => $cycleId,
    ]);
    $row = $stmt->fetch();

    return $row ? normalize_school_cycle_row($row) : null;
}


function school_cycle_rollover_defaults(?array $selectedCycle = null): array
{
    return [
        'source_cycle_id' => $selectedCycle ? (int) ($selectedCycle['id'] ?? 0) : 0,
        'copy_teachers' => true,
        'copy_assessments' => true,
        'copy_students' => false,
    ];
}

function school_cycle_rollover_input(int $centerApplicationId, array $input, ?array $selectedCycle = null): array
{
    $defaults = school_cycle_rollover_defaults($selectedCycle);
    $sourceCycleId = isset($input['source_cycle_id']) ? (int) $input['source_cycle_id'] : (int) $defaults['source_cycle_id'];
    $sourceCycle = $sourceCycleId > 0 ? get_school_cycle($centerApplicationId, $sourceCycleId) : null;

    return [
        'source_cycle_id' => $sourceCycle ? (int) ($sourceCycle['id'] ?? 0) : 0,
        'source_cycle' => $sourceCycle,
        'copy_teachers' => isset($input['copy_teachers']) ? (bool) $input['copy_teachers'] : false,
        'copy_assessments' => isset($input['copy_assessments']) ? (bool) $input['copy_assessments'] : false,
        'copy_students' => isset($input['copy_students']) ? (bool) $input['copy_students'] : false,
    ];
}

function copy_school_cycle_rollover(PDO $pdo, int $centerApplicationId, int $sourceCycleId, int $targetCycleId, array $rollover): array
{
    $summary = [
        'teachers' => 0,
        'assessments' => 0,
        'students' => 0,
    ];

    if (!empty($rollover['copy_teachers'])) {
        $stmt = $pdo->prepare(
            'INSERT INTO school_teachers (
                center_application_id, cycle_id, full_name, role_title, specialization,
                phone, email, employment_status, notes,
                created_at, updated_at
            )
            SELECT
                center_application_id, :target_cycle_id, full_name, role_title, specialization,
                phone, email, employment_status, notes,
                NOW(), NOW()
            FROM school_teachers
            WHERE center_application_id = :center_application_id AND cycle_id = :source_cycle_id'
        );
        $stmt->execute([
            ':target_cycle_id' => $targetCycleId,
            ':center_application_id' => $centerApplicationId,
            ':source_cycle_id' => $sourceCycleId,
        ]);
        $summary['teachers'] = $stmt->rowCount();
    }

    if (!empty($rollover['copy_assessments'])) {
        $stmt = $pdo->prepare(
            'INSERT INTO school_assessment_types (
                center_application_id, cycle_id, title, category, scale_type,
                max_score, weight_percentage, is_active, notes,
                created_at, updated_at
            )
            SELECT
                center_application_id, :target_cycle_id, title, category, scale_type,
                max_score, weight_percentage, is_active, notes,
                NOW(), NOW()
            FROM school_assessment_types
            WHERE center_application_id = :center_application_id AND cycle_id = :source_cycle_id'
        );
        $stmt->execute([
            ':target_cycle_id' => $targetCycleId,
            ':center_application_id' => $centerApplicationId,
            ':source_cycle_id' => $sourceCycleId,
        ]);
        $summary['assessments'] = $stmt->rowCount();
    }

    if (!empty($rollover['copy_students'])) {
        $stmt = $pdo->prepare(
            "INSERT INTO school_students (
                center_application_id, cycle_id, student_code, full_name, gender, grade_level,
                guardian_name, guardian_phone, birth_date, enrollment_status, notes,
                created_at, updated_at
            )
            SELECT
                center_application_id, :target_cycle_id, student_code, full_name, gender, grade_level,
                guardian_name, guardian_phone, birth_date, enrollment_status, notes,
                NOW(), NOW()
            FROM school_students
            WHERE center_application_id = :center_application_id
              AND cycle_id = :source_cycle_id
              AND enrollment_status IN ('active', 'waiting')"
        );
        $stmt->execute([
            ':target_cycle_id' => $targetCycleId,
            ':center_application_id' => $centerApplicationId,
            ':source_cycle_id' => $sourceCycleId,
        ]);
        $summary['students'] = $stmt->rowCount();
    }

    return $summary;
}

function create_school_cycle(int $centerApplicationId, array $data, array $rollover = []): array
{
    $pdo = db_connection();
    $season = $data['season'];
    $year = (int) $data['year'];
    $cycleName = format_school_cycle_name($season, $year);
    $rollover = array_merge(school_cycle_rollover_defaults(), $rollover);
    $sourceCycleId = (int) ($rollover['source_cycle_id'] ?? 0);

    $pdo->beginTransaction();
    try {
        $sourceCycle = null;
        if ($sourceCycleId > 0) {
            $sourceStmt = $pdo->prepare('SELECT * FROM school_cycles WHERE center_application_id = :center_application_id AND id = :id LIMIT 1');
            $sourceStmt->execute([
                ':center_application_id' => $centerApplicationId,
                ':id' => $sourceCycleId,
            ]);
            $sourceCycleRow = $sourceStmt->fetch();
            if ($sourceCycleRow) {
                $sourceCycle = normalize_school_cycle_row($sourceCycleRow);
            } elseif (!empty($rollover['copy_teachers']) || !empty($rollover['copy_assessments']) || !empty($rollover['copy_students'])) {
                throw new InvalidArgumentException('Source cycle not found for rollover.');
            }
        }

        if ($data['status'] === 'active') {
            $archiveStmt = $pdo->prepare(
                "UPDATE school_cycles
                 SET status = 'archived', archived_at = COALESCE(archived_at, NOW()), updated_at = NOW()
                 WHERE center_application_id = :center_application_id AND status = 'active'"
            );
            $archiveStmt->execute([':center_application_id' => $centerApplicationId]);
        }

        $insert = $pdo->prepare(
            'INSERT INTO school_cycles (
                center_application_id, season, year, cycle_name, start_date, end_date,
                status, archived_at, created_at, updated_at
            ) VALUES (
                :center_application_id, :season, :year, :cycle_name, :start_date, :end_date,
                :status, :archived_at, NOW(), NOW()
            )'
        );
        $insert->execute([
            ':center_application_id' => $centerApplicationId,
            ':season' => $season,
            ':year' => $year,
            ':cycle_name' => $cycleName,
            ':start_date' => $data['start_date'],
            ':end_date' => $data['end_date'],
            ':status' => $data['status'],
            ':archived_at' => $data['status'] === 'archived' ? date('Y-m-d H:i:s') : null,
        ]);

        $cycleId = (int) $pdo->lastInsertId();
        $rolloverSummary = ['teachers' => 0, 'assessments' => 0, 'students' => 0];

        if ($sourceCycle && ($rollover['copy_teachers'] || $rollover['copy_assessments'] || $rollover['copy_students'])) {
            $rolloverSummary = copy_school_cycle_rollover($pdo, $centerApplicationId, (int) $sourceCycle['id'], $cycleId, $rollover);
        }

        $pdo->commit();

        return [
            'cycle_id' => $cycleId,
            'cycle_name' => $cycleName,
            'source_cycle_name' => $sourceCycle ? (string) ($sourceCycle['cycle_name'] ?? '') : '',
            'rollover' => $rolloverSummary,
        ];
    } catch (Throwable $exception) {
        if ($pdo->inTransaction()) {
            $pdo->rollBack();
        }
        throw $exception;
    }
}

function archive_school_cycle(int $centerApplicationId, int $cycleId): void
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        "UPDATE school_cycles
         SET status = 'archived', archived_at = COALESCE(archived_at, NOW()), updated_at = NOW()
         WHERE center_application_id = :center_application_id AND id = :id"
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':id' => $cycleId,
    ]);
}

function resolve_school_cycle_context(int $centerApplicationId, ?array $application, int $requestedCycleId = 0): array
{
    if ($application && (string) ($application['status'] ?? '') === 'approved') {
        $pdo = db_connection();
        ensure_default_school_cycle_record($pdo, $application);
    }

    $cycles = list_school_cycles($centerApplicationId);
    $selected = null;
    $active = null;

    foreach ($cycles as $cycle) {
        if ($cycle['status'] === 'active' && $active === null) {
            $active = $cycle;
        }
        if ($requestedCycleId > 0 && (int) $cycle['id'] === $requestedCycleId) {
            $selected = $cycle;
        }
    }

    if ($selected === null) {
        $selected = $active ?? ($cycles[0] ?? null);
    }

    return [
        'cycles' => $cycles,
        'selected' => $selected,
        'active' => $active,
        'read_only' => $selected ? ((string) ($selected['status'] ?? '') === 'archived') : false,
    ];
}

function school_page_url(string $page, int $applicationId, ?int $cycleId = null): string
{
    $url = $page . '?id=' . urlencode((string) $applicationId);
    if ($cycleId !== null && $cycleId > 0) {
        $url .= '&cycle=' . urlencode((string) $cycleId);
    }
    return $url;
}

function create_student_in_cycle(int $centerApplicationId, int $cycleId, array $data): int
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'INSERT INTO school_students (
            center_application_id, cycle_id, student_code, full_name, gender, grade_level,
            guardian_name, guardian_phone, birth_date, enrollment_status, notes,
            created_at, updated_at
        ) VALUES (
            :center_application_id, :cycle_id, :student_code, :full_name, :gender, :grade_level,
            :guardian_name, :guardian_phone, :birth_date, :enrollment_status, :notes,
            NOW(), NOW()
        )'
    );

    $stmt->bindValue(':center_application_id', $centerApplicationId, PDO::PARAM_INT);
    $stmt->bindValue(':cycle_id', $cycleId, PDO::PARAM_INT);
    $stmt->bindValue(':student_code', $data['student_code'], PDO::PARAM_STR);
    $stmt->bindValue(':full_name', $data['full_name'], PDO::PARAM_STR);
    $stmt->bindValue(':gender', $data['gender'], PDO::PARAM_STR);
    $stmt->bindValue(':grade_level', $data['grade_level'], PDO::PARAM_STR);
    $stmt->bindValue(':guardian_name', $data['guardian_name'], PDO::PARAM_STR);
    $stmt->bindValue(':guardian_phone', $data['guardian_phone'], PDO::PARAM_STR);
    $stmt->bindValue(':birth_date', $data['birth_date'] !== '' ? $data['birth_date'] : null, $data['birth_date'] !== '' ? PDO::PARAM_STR : PDO::PARAM_NULL);
    $stmt->bindValue(':enrollment_status', $data['enrollment_status'], PDO::PARAM_STR);
    $stmt->bindValue(':notes', $data['notes'] !== '' ? $data['notes'] : null, $data['notes'] !== '' ? PDO::PARAM_STR : PDO::PARAM_NULL);
    $stmt->execute();

    return (int) $pdo->lastInsertId();
}

function list_school_students_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'SELECT * FROM school_students
         WHERE center_application_id = :center_application_id AND cycle_id = :cycle_id
         ORDER BY created_at DESC, id DESC'
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    return $stmt->fetchAll();
}

function school_student_metrics_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        "SELECT
            COUNT(*) AS total,
            COALESCE(SUM(gender = 'طالب'), 0) AS boys_count,
            COALESCE(SUM(gender = 'طالبة'), 0) AS girls_count,
            COALESCE(SUM(enrollment_status = 'active'), 0) AS active_count,
            COALESCE(SUM(enrollment_status = 'waiting'), 0) AS waiting_count,
            COALESCE(SUM(enrollment_status = 'withdrawn'), 0) AS withdrawn_count
         FROM school_students
         WHERE center_application_id = :center_application_id AND cycle_id = :cycle_id"
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    $row = $stmt->fetch() ?: [];

    return [
        'total' => (int) ($row['total'] ?? 0),
        'boys' => (int) ($row['boys_count'] ?? 0),
        'girls' => (int) ($row['girls_count'] ?? 0),
        'active' => (int) ($row['active_count'] ?? 0),
        'waiting' => (int) ($row['waiting_count'] ?? 0),
        'withdrawn' => (int) ($row['withdrawn_count'] ?? 0),
    ];
}

function create_teacher_in_cycle(int $centerApplicationId, int $cycleId, array $data): int
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'INSERT INTO school_teachers (
            center_application_id, cycle_id, full_name, role_title, specialization,
            phone, email, employment_status, notes,
            created_at, updated_at
        ) VALUES (
            :center_application_id, :cycle_id, :full_name, :role_title, :specialization,
            :phone, :email, :employment_status, :notes,
            NOW(), NOW()
        )'
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
        ':full_name' => $data['full_name'],
        ':role_title' => $data['role_title'],
        ':specialization' => $data['specialization'] !== '' ? $data['specialization'] : null,
        ':phone' => $data['phone'] !== '' ? $data['phone'] : null,
        ':email' => $data['email'] !== '' ? $data['email'] : null,
        ':employment_status' => $data['employment_status'],
        ':notes' => $data['notes'] !== '' ? $data['notes'] : null,
    ]);
    return (int) $pdo->lastInsertId();
}

function list_school_teachers_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'SELECT * FROM school_teachers
         WHERE center_application_id = :center_application_id AND cycle_id = :cycle_id
         ORDER BY created_at DESC, id DESC'
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    return $stmt->fetchAll();
}

function school_teacher_metrics_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        "SELECT
            COUNT(*) AS total,
            COALESCE(SUM(employment_status = 'active'), 0) AS active_count,
            COALESCE(SUM(employment_status = 'pending'), 0) AS pending_count,
            COALESCE(SUM(employment_status = 'inactive'), 0) AS inactive_count,
            COALESCE(SUM(role_title = 'معلم' OR role_title = 'معلمة'), 0) AS teachers_count,
            COALESCE(SUM(role_title LIKE '%مشرف%' OR role_title LIKE '%منسق%'), 0) AS supervisors_count,
            COALESCE(SUM(email IS NOT NULL AND email <> ''), 0) AS email_ready_count
         FROM school_teachers
         WHERE center_application_id = :center_application_id AND cycle_id = :cycle_id"
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    $row = $stmt->fetch() ?: [];

    return [
        'total' => (int) ($row['total'] ?? 0),
        'active' => (int) ($row['active_count'] ?? 0),
        'pending' => (int) ($row['pending_count'] ?? 0),
        'inactive' => (int) ($row['inactive_count'] ?? 0),
        'teachers' => (int) ($row['teachers_count'] ?? 0),
        'supervisors' => (int) ($row['supervisors_count'] ?? 0),
        'email_ready' => (int) ($row['email_ready_count'] ?? 0),
    ];
}

function create_assessment_type_in_cycle(int $centerApplicationId, int $cycleId, array $data): int
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'INSERT INTO school_assessment_types (
            center_application_id, cycle_id, title, category, scale_type,
            max_score, weight_percentage, is_active, notes,
            created_at, updated_at
        ) VALUES (
            :center_application_id, :cycle_id, :title, :category, :scale_type,
            :max_score, :weight_percentage, :is_active, :notes,
            NOW(), NOW()
        )'
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
        ':title' => $data['title'],
        ':category' => $data['category'],
        ':scale_type' => $data['scale_type'],
        ':max_score' => (float) $data['max_score'],
        ':weight_percentage' => (float) $data['weight_percentage'],
        ':is_active' => (int) $data['is_active'],
        ':notes' => $data['notes'] !== '' ? $data['notes'] : null,
    ]);
    return (int) $pdo->lastInsertId();
}

function list_school_assessments_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'SELECT * FROM school_assessment_types
         WHERE center_application_id = :center_application_id AND cycle_id = :cycle_id
         ORDER BY is_active DESC, created_at DESC, id DESC'
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    return $stmt->fetchAll();
}

function school_assessment_metrics_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        "SELECT
            COUNT(*) AS total,
            COALESCE(SUM(is_active = 1), 0) AS active_count,
            COALESCE(SUM(is_active = 0), 0) AS inactive_count,
            COALESCE(SUM(weight_percentage), 0) AS total_weight,
            COALESCE(SUM(CASE WHEN is_active = 1 THEN weight_percentage ELSE 0 END), 0) AS active_weight,
            COALESCE(AVG(max_score), 0) AS average_max_score,
            COALESCE(SUM(scale_type = 'percentage'), 0) AS percentage_count,
            COALESCE(SUM(scale_type = 'points'), 0) AS points_count,
            COALESCE(SUM(scale_type = 'rubric'), 0) AS rubric_count
         FROM school_assessment_types
         WHERE center_application_id = :center_application_id AND cycle_id = :cycle_id"
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    $row = $stmt->fetch() ?: [];

    return [
        'total' => (int) ($row['total'] ?? 0),
        'active' => (int) ($row['active_count'] ?? 0),
        'inactive' => (int) ($row['inactive_count'] ?? 0),
        'total_weight' => (float) ($row['total_weight'] ?? 0),
        'active_weight' => (float) ($row['active_weight'] ?? 0),
        'average_max_score' => (float) ($row['average_max_score'] ?? 0),
        'percentage' => (int) ($row['percentage_count'] ?? 0),
        'points' => (int) ($row['points_count'] ?? 0),
        'rubric' => (int) ($row['rubric_count'] ?? 0),
    ];
}

function school_student_options_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $students = list_school_students_by_cycle($centerApplicationId, $cycleId);
    $options = [];
    foreach ($students as $student) {
        $studentId = (int) ($student['id'] ?? 0);
        if ($studentId <= 0) {
            continue;
        }

        $options[$studentId] = [
            'label' => trim((string) ($student['full_name'] ?? '')),
            'status' => (string) ($student['enrollment_status'] ?? ''),
            'grade_level' => (string) ($student['grade_level'] ?? ''),
            'guardian_phone' => (string) ($student['guardian_phone'] ?? ''),
        ];
    }

    return $options;
}

function validate_attendance_input_for_cycle(int $centerApplicationId, int $cycleId, array $input): array
{
    $data = attendance_defaults();
    $data['student_id'] = (string) ((int) ($input['student_id'] ?? 0));
    $data['attendance_status'] = clean_text((string) ($input['attendance_status'] ?? ''), 30);
    $data['absence_reason'] = clean_text((string) ($input['absence_reason'] ?? ''), 190);
    $data['notes'] = clean_text((string) ($input['notes'] ?? ''), 1000);
    $data['attendance_date'] = clean_text((string) ($input['attendance_date'] ?? ''), 20);

    $errors = [];
    $studentId = (int) $data['student_id'];
    $studentOptions = school_student_options_by_cycle($centerApplicationId, $cycleId);

    if ($studentId <= 0 || !array_key_exists($studentId, $studentOptions)) {
        $errors['student_id'] = 'يرجى اختيار طالب صحيح من نفس الدورة الموسمية.';
    }

    $statusMap = attendance_status_map();
    if (!array_key_exists($data['attendance_status'], $statusMap)) {
        $errors['attendance_status'] = 'يرجى اختيار حالة غياب صحيحة.';
    }

    if ($data['attendance_date'] === '' || strtotime($data['attendance_date']) === false) {
        $errors['attendance_date'] = 'يرجى إدخال تاريخ صحيح للسجل اليومي.';
    }

    if ($data['attendance_status'] !== 'late' && $data['absence_reason'] === '') {
        $errors['absence_reason'] = 'يرجى إدخال سبب الغياب أو العذر.';
    }

    return [$data, $errors];
}

function create_attendance_record_in_cycle(int $centerApplicationId, int $cycleId, array $data): int
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'INSERT INTO school_attendance_records (
            center_application_id, cycle_id, student_id, attendance_date, attendance_status,
            absence_reason, notes, created_at, updated_at
        ) VALUES (
            :center_application_id, :cycle_id, :student_id, :attendance_date, :attendance_status,
            :absence_reason, :notes, NOW(), NOW()
        )'
    );

    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
        ':student_id' => (int) $data['student_id'],
        ':attendance_date' => $data['attendance_date'],
        ':attendance_status' => $data['attendance_status'],
        ':absence_reason' => $data['absence_reason'] !== '' ? $data['absence_reason'] : null,
        ':notes' => $data['notes'] !== '' ? $data['notes'] : null,
    ]);

    return (int) $pdo->lastInsertId();
}

function list_school_attendance_records_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        'SELECT ar.*, s.student_code, s.full_name, s.grade_level, s.guardian_phone
         FROM school_attendance_records ar
         INNER JOIN school_students s ON s.id = ar.student_id
         WHERE ar.center_application_id = :center_application_id AND ar.cycle_id = :cycle_id
         ORDER BY ar.attendance_date DESC, ar.created_at DESC, ar.id DESC'
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    return $stmt->fetchAll();
}

function school_attendance_metrics_by_cycle(int $centerApplicationId, int $cycleId): array
{
    $pdo = db_connection();
    $stmt = $pdo->prepare(
        "SELECT
            COUNT(*) AS total,
            COALESCE(SUM(attendance_status = 'absent'), 0) AS absent_count,
            COALESCE(SUM(attendance_status = 'excused'), 0) AS excused_count,
            COALESCE(SUM(attendance_status = 'late'), 0) AS late_count,
            COUNT(DISTINCT student_id) AS affected_students,
            MAX(attendance_date) AS latest_date,
            COALESCE(SUM(attendance_date = CURDATE()), 0) AS today_count
         FROM school_attendance_records
         WHERE center_application_id = :center_application_id AND cycle_id = :cycle_id"
    );
    $stmt->execute([
        ':center_application_id' => $centerApplicationId,
        ':cycle_id' => $cycleId,
    ]);
    $row = $stmt->fetch() ?: [];

    return [
        'total' => (int) ($row['total'] ?? 0),
        'absent' => (int) ($row['absent_count'] ?? 0),
        'excused' => (int) ($row['excused_count'] ?? 0),
        'late' => (int) ($row['late_count'] ?? 0),
        'affected_students' => (int) ($row['affected_students'] ?? 0),
        'latest_date' => (string) ($row['latest_date'] ?? ''),
        'today_count' => (int) ($row['today_count'] ?? 0),
    ];
}