<?php
declare(strict_types=1);

class TaskCertificateRepository
{
    public function create(array $data): int
    {
        return TaskCertDb::insert(
            'INSERT INTO task_certificate (
                task_id,
                assignment_id,
                submission_id,
                main_contact_id,
                certificate_code,
                valid_from,
                valid_until,
                status
             ) VALUES (?, ?, ?, ?, ?, ?, ?, ?)',
            'iiiissss',
            [
                $data['task_id'],
                $data['assignment_id'],
                $data['submission_id'],
                $data['main_contact_id'],
                $data['certificate_code'],
                $data['valid_from'],
                $data['valid_until'],
                $data['status'],
            ]
        );
    }

    public function findByAssignmentId(int $assignmentId): ?array
    {
        return TaskCertDb::fetchOne(
            'SELECT * FROM task_certificate WHERE assignment_id = ? LIMIT 1',
            'i',
            [$assignmentId]
        );
    }

    public function listAssignmentIdsWithCertificates(array $assignmentIds): array
    {
        $assignmentIds = array_values(array_unique(array_map('intval', $assignmentIds)));
        $assignmentIds = array_values(array_filter($assignmentIds, static function (int $assignmentId): bool {
            return $assignmentId > 0;
        }));

        if ($assignmentIds === []) {
            return [];
        }

        $placeholders = implode(',', array_fill(0, count($assignmentIds), '?'));
        $rows = TaskCertDb::fetchAll(
            'SELECT DISTINCT assignment_id
             FROM task_certificate
             WHERE assignment_id IN (' . $placeholders . ')',
            str_repeat('i', count($assignmentIds)),
            $assignmentIds
        );

        $result = [];
        foreach ($rows as $row) {
            $assignmentId = (int) ($row['assignment_id'] ?? 0);
            if ($assignmentId <= 0) {
                continue;
            }

            $result[] = $assignmentId;
        }

        $result = array_values(array_unique($result));
        sort($result);

        return $result;
    }

    public function listForUser(int $contactId): array
    {
        return TaskCertDb::fetchAll(
            'SELECT c.*, d.title AS task_title
             FROM task_certificate c
             INNER JOIN task_definition d ON d.id = c.task_id
             WHERE c.main_contact_id = ?
             ORDER BY c.issued_at DESC',
            'i',
            [$contactId]
        );
    }

    public function listForUserTask(int $contactId, int $taskId): array
    {
        return TaskCertDb::fetchAll(
            'SELECT c.*, a.cycle_key
             FROM task_certificate c
             LEFT JOIN task_assignment a ON a.id = c.assignment_id
             WHERE c.main_contact_id = ?
               AND c.task_id = ?
             ORDER BY c.issued_at DESC, c.id DESC',
            'ii',
            [$contactId, $taskId]
        );
    }

    public function summarizeForUserTasks(int $contactId, array $taskIds): array
    {
        $taskIds = array_values(array_unique(array_map('intval', $taskIds)));
        $taskIds = array_values(array_filter($taskIds, static function (int $taskId): bool {
            return $taskId > 0;
        }));

        if ($taskIds === []) {
            return [];
        }

        $placeholders = implode(',', array_fill(0, count($taskIds), '?'));
        $sql = 'SELECT
                c.task_id,
                COUNT(*) AS total_count,
                SUM(CASE WHEN c.status = "valid" THEN 1 ELSE 0 END) AS valid_count,
                MAX(c.issued_at) AS latest_issued_at,
                (
                    SELECT c2.valid_until
                    FROM task_certificate c2
                    WHERE c2.main_contact_id = c.main_contact_id
                      AND c2.task_id = c.task_id
                    ORDER BY c2.issued_at DESC, c2.id DESC
                    LIMIT 1
                ) AS latest_valid_until
             FROM task_certificate c
             WHERE c.main_contact_id = ?
               AND c.task_id IN (' . $placeholders . ')
             GROUP BY c.task_id';

        $types = 'i' . str_repeat('i', count($taskIds));
        $params = array_merge([$contactId], $taskIds);
        $rows = TaskCertDb::fetchAll($sql, $types, $params);

        $summaryByTask = [];
        foreach ($rows as $row) {
            $taskId = (int) ($row['task_id'] ?? 0);
            if ($taskId <= 0) {
                continue;
            }

            $summaryByTask[$taskId] = [
                'task_id' => $taskId,
                'total_count' => (int) ($row['total_count'] ?? 0),
                'valid_count' => (int) ($row['valid_count'] ?? 0),
                'latest_issued_at' => (string) ($row['latest_issued_at'] ?? ''),
                'latest_valid_until' => (string) ($row['latest_valid_until'] ?? ''),
            ];
        }

        return $summaryByTask;
    }

    public function deleteByAssignmentIds(array $assignmentIds): int
    {
        $assignmentIds = array_values(array_unique(array_map('intval', $assignmentIds)));
        $assignmentIds = array_values(array_filter($assignmentIds, static function (int $assignmentId): bool {
            return $assignmentId > 0;
        }));

        if ($assignmentIds === []) {
            return 0;
        }

        $placeholders = implode(',', array_fill(0, count($assignmentIds), '?'));
        $types = str_repeat('i', count($assignmentIds));

        return TaskCertDb::execute(
            'DELETE FROM task_certificate WHERE assignment_id IN (' . $placeholders . ')',
            $types,
            $assignmentIds
        );
    }

    public function revokeByAssignmentIds(array $assignmentIds, int $revokedBy, string $reason): int
    {
        $assignmentIds = array_values(array_unique(array_map('intval', $assignmentIds)));
        $assignmentIds = array_values(array_filter($assignmentIds, static function (int $assignmentId): bool {
            return $assignmentId > 0;
        }));

        if ($assignmentIds === []) {
            return 0;
        }

        $placeholders = implode(',', array_fill(0, count($assignmentIds), '?'));
        $types = 'is' . str_repeat('i', count($assignmentIds));
        $params = array_merge([$revokedBy, $reason], $assignmentIds);

        return TaskCertDb::execute(
            'UPDATE task_certificate
             SET status = "revoked",
                 revoked_at = COALESCE(revoked_at, NOW()),
                 revoked_by = ?,
                 revoke_reason = ?
             WHERE assignment_id IN (' . $placeholders . ')
               AND status <> "revoked"',
            $types,
            $params
        );
    }

    public function markExpiredByDate(string $now): int
    {
        return TaskCertDb::execute(
            'UPDATE task_certificate
             SET status = "expired"
             WHERE status = "valid"
               AND valid_until IS NOT NULL
               AND valid_until < ?',
            's',
            [$now]
        );
    }
}