<?php

/**
 * 迁移脚本：为支持 Dify 接口新增所需字段（已存在则跳过）
 * 用法: php database/migrate_add_dify_support.php
 */

$host = '127.0.0.1';
$user = 'root';
$pass = 'root';
$port = 3306;
$dbName = 'ai_chat';

try {
    $pdo = new PDO("mysql:host={$host};port={$port};dbname={$dbName};charset=utf8mb4", $user, $pass, [
        PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
    ]);

    $changes = [
        ['table' => 'ai_models', 'column' => 'provider', 'sql' => "ALTER TABLE ai_models ADD COLUMN provider VARCHAR(20) NOT NULL DEFAULT 'openai' COMMENT '接口类型：openai/dify' AFTER name"],
        ['table' => 'conversations', 'column' => 'external_conversation_id', 'sql' => "ALTER TABLE conversations ADD COLUMN external_conversation_id VARCHAR(64) NULL COMMENT '第三方平台会话ID' AFTER message_count"],
    ];

    foreach ($changes as $change) {
        $exists = $pdo->query("SHOW COLUMNS FROM {$change['table']} LIKE '{$change['column']}'")->fetch();
        if ($exists) {
            echo "{$change['table']}.{$change['column']} 已存在，跳过。\n";
            continue;
        }
        $pdo->exec($change['sql']);
        echo "已为 {$change['table']} 添加 {$change['column']} 字段。\n";
    }
} catch (PDOException $e) {
    echo "Error: " . $e->getMessage() . "\n";
    exit(1);
}