<?php

/**
 * TestDatabase — helper for integration tests that need a real SQLite database.
 *
 * Creates an in-memory SQLite database, loads the full schema + seed data,
 * and provides a Database instance connected to it. Teardown discards the DB.
 */

/**
 * Thin Database subclass that accepts a pre-built PDO connection.
 * Bypasses the normal path-based constructor.
 */
class TestDatabaseInstance extends Database
{
    public function __construct(PDO $pdo)
    {
        // Inject PDO directly via reflection, then flag as ready
        $ref = new ReflectionProperty(Database::class, 'pdo');
        $ref->setValue($this, $pdo);

        $pathRef = new ReflectionProperty(Database::class, 'dbPath');
        $pathRef->setValue($this, ':memory:');
    }
}

class TestDatabase
{
    private static ?PDO $pdo = null;
    private static ?Database $db = null;

    /**
     * Get or create the shared test Database instance.
     * Uses an in-memory SQLite DB so tests are fast and isolated.
     */
    public static function getInstance(): Database
    {
        if (self::$db === null) {
            self::$pdo = new PDO('sqlite::memory:');
            self::$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
            self::$pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
            self::$pdo->exec('PRAGMA foreign_keys = ON');
            self::$pdo->exec('PRAGMA journal_mode = MEMORY');

            // Load schema
            $schema = file_get_contents(APP_ROOT . '/storage/schema.sql');
            if ($schema === false) {
                throw new RuntimeException('Failed to read schema.sql');
            }
            self::$pdo->exec($schema);

            // Create a Database wrapper injecting our PDO
            self::$db = new TestDatabaseInstance(self::$pdo);
        }

        return self::$db;
    }

    /**
     * Get the raw PDO connection (for queries that bypass the Database class).
     */
    public static function getPDO(): PDO
    {
        // Ensure the DB is booted
        self::getInstance();
        return self::$pdo;
    }

    /**
     * Reset all test data between tests.
     * Preserves seed data (orientations, access types, etc.) but removes
     * any theses, authors, tags, share links etc. created during a test.
     */
    public static function resetData(): void
    {
        $pdo = self::getPDO();
        // Order matters due to FK constraints
        $tables = [
            'file_access_audit',
            'file_access_sessions',
            'file_access_tokens',
            'file_access_requests',
            'thesis_files',
            'thesis_tags',
            'thesis_formats',
            'thesis_languages',
            'thesis_supervisors',
            'thesis_authors',
            'theses',
            'share_links',
            'tags',
            'authors',
            'supervisors',
            'admin_audit_log',
            'audit_log',
        ];
        foreach ($tables as $table) {
            $pdo->exec("DELETE FROM $table");
        }
        // Re-seed tags (some tests rely on tags existing)
        try {
            $pdo->exec("DELETE FROM tags WHERE deleted_at IS NOT NULL");
        } catch (Exception $e) {
            // tags table already empty
        }
    }

    /**
     * Seed some basic test data: an author, a thesis.
     * Returns [authorId, thesisId].
     *
     * @return array{0: int, 1: int}
     */
    public static function seedBasicThesis(string $title = 'Test Thesis', string $authorName = 'Test Author', int $year = 2024): array
    {
        $pdo = self::getPDO();

        // Insert author
        $pdo->prepare('INSERT INTO authors (name) VALUES (?)')->execute([$authorName]);
        $authorId = (int)$pdo->lastInsertId();

        // Insert thesis
        $pdo->prepare(
            "INSERT INTO theses (title, year, identifier, is_published, objet) VALUES (?, ?, ?, 1, 'tfe')"
        )->execute([$title, $year, "$year-001"]);

        $thesisId = (int)$pdo->lastInsertId();

        // Link author
        $pdo->prepare('INSERT INTO thesis_authors (thesis_id, author_id) VALUES (?, ?)')
            ->execute([$thesisId, $authorId]);

        // Insert a cover file
        $pdo->prepare(
            "INSERT INTO thesis_files (thesis_id, file_type, file_path, file_name, file_size, mime_type) VALUES (?, 'cover', ?, ?, 0, 'image/jpeg')"
        )->execute([$thesisId, "documents/$year-001/cover.jpg", 'cover.jpg']);

        return [$authorId, $thesisId];
    }
}