<?php

declare(strict_types=1);

namespace App\Service;

use InvalidArgumentException;
use App\Entity\SystemConfig;
use App\Repository\SystemConfigRepository;
use App\Enum\SystemSettingKey;

class ConfigurationService
{
    // For backward compatibility
    /**
     * @deprecated Use SystemSettingKey::STOCK_ADJUSTMENT_LOOKBACK instead
     */
    public const KEY_STOCK_ADJUSTMENT_LOOKBACK = 'stock_adjustment_lookback';
    /**
     * @deprecated Use SystemSettingKey::STOCK_ADJUSTMENT_LOOKBACK_ORDERS instead
     */
    public const KEY_STOCK_ADJUSTMENT_LOOKBACK_ORDERS = 'stock_adjustment_lookback_orders';
    /**
     * @deprecated Use SystemSettingKey::STOCK_ADJUSTMENT_MAGNITUDE instead
     */
    public const KEY_STOCK_ADJUSTMENT_MAGNITUDE = 'stock_adjustment_magnitude';
    /**
     * @deprecated Use SystemSettingKey::STOCK_ADJUSTMENT_THRESHOLD instead
     */
    public const KEY_STOCK_ADJUSTMENT_THRESHOLD = 'stock_adjustment_threshold';
    /**
     * @deprecated Use SystemSettingKey::LOW_STOCK_THRESHOLD instead
     */
    public const KEY_LOW_STOCK_THRESHOLD = 'low_stock_threshold';
    /**
     * @deprecated Use SystemSettingKey::CRITICAL_STOCK_THRESHOLD instead
     */
    public const KEY_CRITICAL_STOCK_THRESHOLD = 'critical_stock_threshold';
    /**
     * @deprecated Use SystemSettingKey::DEFAULT_DESIRED_STOCK instead
     */
    public const KEY_DEFAULT_DESIRED_STOCK = 'default_desired_stock';
    /**
     * @deprecated Use SystemSettingKey::SYSTEM_NAME instead
     */
    public const KEY_SYSTEM_NAME = 'system_name';
    /**
     * @deprecated Use SystemSettingKey::ENABLE_AUTO_ADJUSTMENT instead
     */
    public const KEY_ENABLE_AUTO_ADJUSTMENT = 'enable_auto_adjustment';
    /**
     * @deprecated Use SystemSettingKey::SHOW_LOW_STOCK_ALERTS instead
     */
    public const KEY_SHOW_LOW_STOCK_ALERTS = 'show_low_stock_alerts';
    /**
     * @deprecated Use SystemSettingKey::SHOW_QUICK_UPDATE_FORM instead
     */
    public const KEY_SHOW_QUICK_UPDATE_FORM = 'show_quick_update_form';
    /**
     * @deprecated Use SystemSettingKey::ITEMS_PER_PAGE instead
     */
    public const KEY_ITEMS_PER_PAGE = 'items_per_page';

    public function __construct(
        private readonly SystemConfigRepository $systemConfigRepository
    ) {}

    /**
     * Get all configuration entries
     *
     * @return SystemConfig[]
     */
    public function getAllConfigs(): array
    {
        return $this->systemConfigRepository->findAll();
    }

    /**
     * Get a configuration value by key
     *
     * @param string $key
     * @param string $default Default value if the key doesn't exist
     * @return string
     */
    public function getConfigValue(string $key, string $default = ''): string
    {
        return $this->systemConfigRepository->getValue($key, $default);
    }

    /**
     * Set a configuration value
     *
     * @param string $key
     * @param string $value
     * @return void
     */
    public function setConfigValue(string $key, string $value): void
    {
        $this->systemConfigRepository->setValue($key, $value);
    }

    /**
     * Get a configuration entity by key
     *
     * @param string $key
     * @return SystemConfig|null
     */
    public function getConfigByKey(string $key): ?SystemConfig
    {
        return $this->systemConfigRepository->findByKey($key);
    }

    /**
     * Create a new configuration entry
     *
     * @param string $key
     * @param string $value
     * @return SystemConfig
     * @throws InvalidArgumentException If a configuration with the same key already exists
     */
    public function createConfig(string $key, string $value): SystemConfig
    {
        if ($this->systemConfigRepository->findByKey($key) instanceof SystemConfig) {
            throw new InvalidArgumentException("A configuration with the key '$key' already exists");
        }

        $config = new SystemConfig($key, $value);
        $this->systemConfigRepository->save($config);

        return $config;
    }

    /**
     * Update an existing configuration entry
     *
     * @param SystemConfig $config
     * @param string|null $key
     * @param string|null $value
     * @return SystemConfig
     * @throws InvalidArgumentException If a configuration with the same key already exists
     */
    public function updateConfig(
        SystemConfig $config,
        ?string $key = null,
        ?string $value = null
    ): SystemConfig {
        // Update key if provided
        if ($key !== null && $key !== $config->getKey()) {
            // Check if a configuration with the same key already exists
            if ($this->systemConfigRepository->findByKey($key) instanceof SystemConfig) {
                throw new InvalidArgumentException("A configuration with the key '$key' already exists");
            }
            $config->setKey($key);
        }

        // Update value if provided
        if ($value !== null) {
            $config->setValue($value);
        }

        $this->systemConfigRepository->save($config);

        return $config;
    }

    /**
     * Delete a configuration entry
     *
     * @param SystemConfig $config
     * @return void
     */
    public function deleteConfig(SystemConfig $config): void
    {
        $this->systemConfigRepository->remove($config);
    }

    /**
     * Initialize default configuration values if they don't exist
     *
     * @return void
     */
    public function initializeDefaultConfigs(): void
    {
        $defaults = [
            SystemSettingKey::STOCK_ADJUSTMENT_LOOKBACK->value => '30', // Deprecated
            SystemSettingKey::STOCK_ADJUSTMENT_LOOKBACK_ORDERS->value => '5',
            SystemSettingKey::STOCK_ADJUSTMENT_MAGNITUDE->value => '0.2',
            SystemSettingKey::STOCK_ADJUSTMENT_THRESHOLD->value => '0.1',
        ];

        foreach ($defaults as $key => $value) {
            if (!$this->getConfigByKey($key) instanceof SystemConfig) {
                $this->createConfig($key, $value);
            }
        }
    }
}