<?php

declare(strict_types=1);

namespace app\service;

use think\facade\Db;
use think\facade\Config;
use app\model\Cms\TemplateSiteConfig;

/**
 * 模板服务类
 * 负责扫描 public/themes 目录，管理模板配置
 */
class ThemeService
{
    private string $themesPath;

    public function __construct()
    {
        $this->themesPath = root_path() . 'public' . DIRECTORY_SEPARATOR . 'themes';
    }

    /**
     * 获取所有可用模板列表
     * @return array
     */
    public function getThemeList(): array
    {
        $themes = [];
        $dirs = $this->scanThemeDirs();

        foreach ($dirs as $dir) {
            $config = $this->readThemeConfig($dir);
            $preview = $this->getThemePreview($dir);

            $themes[] = [
                'key'        => $dir,
                'name'       => $config['name'] ?? $dir,
                'description' => $config['description'] ?? '',
                'version'    => $config['version'] ?? '1.0.0',
                'author'     => $config['author'] ?? '',
                'preview'    => $preview,
                'path'       => '/themes/' . $dir . '/index.html',
                'fields'     => $config['fields'] ?? [],
            ];
        }

        return $themes;
    }

    /**
     * 扫描模板目录
     * @return array
     */
    private function scanThemeDirs(): array
    {
        $dirs = [];

        if (!is_dir($this->themesPath)) {
            return $dirs;
        }

        $items = scandir($this->themesPath);
        foreach ($items as $item) {
            if ($item === '.' || $item === '..') {
                continue;
            }

            $fullPath = $this->themesPath . DIRECTORY_SEPARATOR . $item;
            // 检查是否有 index.html 或 index.php
            if (is_dir($fullPath) && (is_file($fullPath . DIRECTORY_SEPARATOR . 'index.html') || is_file($fullPath . DIRECTORY_SEPARATOR . 'index.php'))) {
                $dirs[] = $item;
            }
        }

        return $dirs;
    }

    /**
     * 读取模板配置文件
     * @param string $themeDir
     * @return array
     */
    private function readThemeConfig(string $themeDir): array
    {
        $configPath = $this->themesPath . DIRECTORY_SEPARATOR . $themeDir . DIRECTORY_SEPARATOR . 'config.json';

        if (!is_file($configPath)) {
            return [];
        }

        $content = file_get_contents($configPath);
        $config = json_decode($content, true);

        return $config ?? [];
    }

    /**
     * 获取模板预览图
     * @param string $themeDir
     * @return string
     */
    private function getThemePreview(string $themeDir): string
    {
        $previewPath = '/themes/' . $themeDir . '/preview.png';

        // 如果 preview.png 不存在，使用默认占位图
        $fullPath = $this->themesPath . DIRECTORY_SEPARATOR . $themeDir . DIRECTORY_SEPARATOR . 'preview.png';
        if (!is_file($fullPath)) {
            return 'https://picsum.photos/300/200?random=' . ord($themeDir[0]);
        }

        return $previewPath;
    }

    /**
     * 获取当前激活的模板Key
     * @param int $tid 租户ID
     * @return string
     */
    public function getCurrentTheme(int $tid)
    {
        // 直接通过 tid 查询对应的 value
        $value = TemplateSiteConfig::where('tid', $tid)->value('value');

        return $value;
    }

    /**
     * 切换当前模板
     * @param int $tid 租户ID
     * @param string $themeKey
     * @return bool
     */
    public function switchTheme(int $tid, string $themeKey): bool
    {
        // 验证模板是否存在
        $themes = $this->getThemeList();
        $exists = false;
        foreach ($themes as $theme) {
            if ($theme['key'] === $themeKey) {
                $exists = true;
                break;
            }
        }

        if (!$exists) {
            return false;
        }

        try {
            // 查找或创建配置记录
            $where = [['key', '=', 'current_theme'], ['delete_time', '=', null]];
            if ($tid > 0) {
                $where[] = ['tid', '=', $tid];
            }
            $config = TemplateSiteConfig::where($where)
                ->find();

            $now = date('Y-m-d H:i:s');

            if ($config) {
                TemplateSiteConfig::where('id', $config['id'])->update([
                    'value'       => $themeKey,
                    'update_time' => $now
                ]);
            } else {
                TemplateSiteConfig::insert([
                    'tid'         => $tid,
                    'key'         => 'current_theme',
                    'value'       => $themeKey,
                    'create_time' => $now,
                    'update_time' => $now
                ]);
            }

            return true;
        } catch (\Exception $e) {
            return false;
        }
    }

    /**
     * 获取模板数据（用于前端渲染）
     * @param int $tid 租户ID
     * @param string|null $themeKey
     * @return array
     */
    public function getThemeData(int $tid = 0, ?string $themeKey = null): array
    {
        $themeKey = $themeKey ?? $this->getCurrentTheme($tid);

        try {
            if ($tid > 0) {
                $where[] = ['tid', '=', $tid];
            }
            $configData = TemplateSiteConfig::where($where)
                ->select()
                ->toArray();

            $data = [];
            foreach ($configData as $item) {
                // 去掉 field_ 前缀
                $fieldKey = substr($item['key'], 6);
                $data[$fieldKey] = $item['value'];
            }

            return [
                'theme_key' => $themeKey,
                'theme_path' => '/themes/' . $themeKey . '/index.html',
                'data' => $data
            ];
        } catch (\Exception $e) {
            return [
                'theme_key' => $themeKey,
                'theme_path' => '/themes/' . $themeKey . '/index.html',
                'data' => []
            ];
        }
    }

    /**
     * 保存模板字段数据
     * @param int $tid 租户ID
     * @param string $themeKey
     * @param string $fieldKey
     * @param mixed $fieldValue
     * @return bool
     */
    public function saveThemeField(int $tid, string $themeKey, string $fieldKey, $fieldValue): bool
    {
        try {
            // 使用 TemplateSiteConfig 表，key 格式为 field_xxx
            $configKey = 'field_' . $fieldKey;
            $where = [
                ['key', '=', $configKey],
                ['delete_time', '=', null]
            ];
            if ($tid > 0) {
                $where[] = ['tid', '=', $tid];
            }
            $existing = TemplateSiteConfig::where($where)
                ->find();

            $value = is_array($fieldValue) ? json_encode($fieldValue, JSON_UNESCAPED_UNICODE) : $fieldValue;
            $now = date('Y-m-d H:i:s');

            if ($existing) {
                TemplateSiteConfig::where('id', $existing['id'])
                    ->update([
                        'value' => $value,
                        'update_time' => $now
                    ]);
            } else {
                TemplateSiteConfig::insert([
                    'tid'         => $tid,
                    'key'         => $configKey,
                    'value'       => $value,
                    'create_time' => $now,
                    'update_time' => $now
                ]);
            }

            return true;
        } catch (\Exception $e) {
            return false;
        }
    }
}