<?php

require_once __DIR__ . '/../db/config.php';

class Settings
{
    private static $cache = [];

    /**
     * Get a setting value.
     *
     * @param string $key The setting key.
     * @param mixed $default The default value to return if the setting is not found.
     * @return mixed The setting value or the default value.
     */
    public static function get(string $key, $default = null)
    {
        if (isset(self::$cache[$key])) {
            return self::$cache[$key];
        }

        try {
            $pdo = db();
            $stmt = $pdo->prepare("SELECT setting_value, setting_type FROM settings WHERE setting_key = ?");
            $stmt->execute([$key]);
            $row = $stmt->fetch(PDO::FETCH_ASSOC);

            if ($row) {
                $value = self::castValue($row['setting_value'], $row['setting_type']);
                self::$cache[$key] = $value;
                return $value;
            }
        } catch (PDOException $e) {
            error_log("Error getting setting '{$key}': " . $e->getMessage());
        }

        return $default;
    }

    /**
     * Set or update a setting value.
     *
     * @param string $key The setting key.
     * @param mixed $value The setting value.
     * @param string $type The type of the setting (e.g., 'text', 'checkbox', 'number').
     * @param mixed $defaultValue The default value for the setting.
     * @param string|null $validationRules JSON string of validation rules.
     * @param string|null $description A description for the setting.
     * @return bool True on success, false on failure.
     */
    public static function set(
        string $key,
        $value,
        string $type = 'text',
        $defaultValue = null,
        ?string $validationRules = null,
        ?string $description = null
    ): bool {
        try {
            $pdo = db();
            
            // Check if setting exists
            $stmt = $pdo->prepare("SELECT COUNT(*) FROM settings WHERE setting_key = ?");
            $stmt->execute([$key]);
            $exists = $stmt->fetchColumn();

            $stringValue = self::valueToString($value);
            $defaultValue = self::valueToString($defaultValue);

            if ($exists) {
                $stmt = $pdo->prepare("UPDATE settings SET setting_value = ?, setting_type = ?, default_value = ?, validation_rules = ?, description = ?, updated_at = NOW() WHERE setting_key = ?");
                $stmt->execute([$stringValue, $type, $defaultValue, $validationRules, $description, $key]);
            } else {
                $stmt = $pdo->prepare("INSERT INTO settings (setting_key, setting_value, setting_type, default_value, validation_rules, description) VALUES (?, ?, ?, ?, ?, ?)");
                $stmt->execute([$key, $stringValue, $type, $defaultValue, $validationRules, $description]);
            }

            // Clear cache for this key
            unset(self::$cache[$key]);
            return true;
        } catch (PDOException $e) {
            error_log("Error setting '{$key}': " . $e->getMessage());
            return false;
        }
    }

    /**
     * Casts a string value to its appropriate PHP type based on the setting type.
     *
     * @param string $value The string value from the database.
     * @param string $type The declared type of the setting.
     * @return mixed The type-casted value.
     */
    private static function castValue(string $value, string $type)
    {
        switch ($type) {
            case 'boolean':
            case 'checkbox':
                return (bool)$value;
            case 'integer':
            case 'number':
                return (int)$value;
            case 'float':
                return (float)$value;
            case 'json':
                return json_decode($value, true);
            case 'array': // Simple comma-separated array
                return explode(',', $value);
            default:
                return $value;
        }
    }

    /**
     * Converts a PHP value to its string representation for storage.
     *
     * @param mixed $value The PHP value.
     * @return string The string representation.
     */
    private static function valueToString($value): string
    {
        if (is_bool($value)) {
            return $value ? '1' : '0';
        } elseif (is_array($value) || is_object($value)) {
            return json_encode($value);
        } else {
            return (string)$value;
        }
    }

    /**
     * Clears the entire settings cache.
     */
    public static function clearCache(): void
    {
        self::$cache = [];
    }

    /**
     * Fetches all settings from the database.
     *
     * @return array An associative array of all settings.
     */
    public static function getAll(): array
    {
        try {
            $pdo = db();
            $stmt = $pdo->query("SELECT setting_key, setting_value, setting_type FROM settings");
            $allSettings = $stmt->fetchAll(PDO::FETCH_ASSOC);

            $result = [];
            foreach ($allSettings as $setting) {
                $result[$setting['setting_key']] = self::castValue($setting['setting_value'], $setting['setting_type']);
            }
            return $result;
        } catch (PDOException $e) {
            error_log("Error getting all settings: " . $e->getMessage());
            return [];
        }
    }

    /**
     * Fetches all settings with their metadata from the database.
     *
     * @return array An associative array of all settings including metadata.
     */
    public static function getAllWithMetadata(): array
    {
        try {
            $pdo = db();
            $stmt = $pdo->query("SELECT * FROM settings");
            return $stmt->fetchAll(PDO::FETCH_ASSOC);
        } catch (PDOException $e) {
            error_log("Error getting all settings with metadata: " . $e->getMessage());
            return [];
        }
    }
}