/**
 * Dify Chat API 模块
 *
 * 提供客户端调用 Dify API 的函数
 * 用于 Remix loader/action 中调用 Dify API
 *
 * @module api/dify/chat
 */

import { difyFetch } from './client.server';

// ============================================================================
// Dify Chat API 客户端
// ============================================================================

/**
 * Dify Chat API 客户端
 *
 * @param jwt - JWT 认证令牌
 * user 参数由后端自动从 JWT 中提取
 */
export const difyClient = {
    /**
     * 获取应用参数
     */
    async getApplicationParameters(jwt?: string): Promise<any> {
        const response = await difyFetch('parameters', {
            method: 'GET',
        }, jwt);
        return response.json();
    },

    /**
     * 获取会话列表
     *
     * @param jwt - JWT 认证令牌
     * @param appId - 对话应用 ID（可选，用于获取特定应用的会话列表）
     */
    async getConversations(jwt?: string, appId?: string): Promise<any> {
        const params = new URLSearchParams({
            limit: '100',
            first_id: '',
        });

        const response = await difyFetch(`conversations?${params}`, {
            method: 'GET',
            appId, // 传递应用 ID，会在请求头中添加 X-Dify-App-Id
        }, jwt);
        return response.json();
    },

    /**
     * 获取会话消息
     */
    async getConversationMessages(conversationId: string, jwt?: string): Promise<any> {
        const params = new URLSearchParams({
            conversation_id: conversationId,
            limit: '20',
            last_id: '',
        });

        const response = await difyFetch(`messages?${params}`, {
            method: 'GET',
        }, jwt);
        return response.json();
    },

    /**
     * 发送聊天消息
     *
     * @param inputs - 输入参数
     * @param query - 用户问题
     * @param responseMode - 响应模式 ('streaming' | 'blocking')
     * @param conversationId - 会话 ID
     * @param files - 附件文件
     * @param jwt - JWT 认证令牌
     * @param appId - 对话应用 ID（可选，用于切换不同的 Dify 应用）
     * @returns 对于流式响应返回 Response 对象，否则返回 JSON
     */
    async createChatMessage(
        inputs: Record<string, any>,
        query: string,
        responseMode: string = 'streaming',
        conversationId?: string,
        files?: any[],
        jwt?: string,
        appId?: string
    ): Promise<Response | any> {
        const body = {
            inputs,
            query,
            response_mode: responseMode,
            conversation_id: conversationId,
            files: files || [],
        };
        const response = await difyFetch('chat-messages', {
            method: 'POST',
            body: JSON.stringify(body),
            appId, // 传递应用 ID，会在请求头中添加 X-Dify-App-Id
        }, jwt);

        // 对于流式响应，直接返回 Response 对象
        if (responseMode === 'streaming') {
            return response;
        }

        console.log('[Dify Chat] 解析 JSON 响应');
        return response.json();
    },

    /**
     * 重命名会话
     */
    async renameConversation(
        conversationId: string,
        name: string,
        autoGenerate: boolean = false,
        jwt?: string
    ): Promise<any> {
        const body = {
            name,
            auto_generate: autoGenerate,
        };

        const response = await difyFetch(`conversations/${conversationId}/name`, {
            method: 'POST',
            body: JSON.stringify(body),
        }, jwt);
        return response.json();
    },

    /**
     * 删除会话
     */
    async deleteConversation(conversationId: string, jwt?: string): Promise<any> {
        console.log('[Dify Chat] 删除会话:', conversationId);

        try {
            const response = await difyFetch(`conversations/${conversationId}`, {
                method: 'DELETE',
                body: JSON.stringify({}),
            }, jwt);

            // 对于 204 No Content 响应，直接返回成功
            if (response.status === 204) {
                console.log('[Dify Chat] 删除会话成功:', conversationId);
                return { result: 'success' };
            }

            const contentType = response.headers.get('Content-Type');

            if (contentType && contentType.includes('application/json')) {
                const data = await response.json();
                return data;
            }

            const text = await response.text();
            console.log('[Dify Chat] 删除会话文本响应:', text);

            return { result: 'success' };
        } catch (error: any) {
            // 权限不足等明确错误需要抛出，不能吞掉
            if (error.message?.includes('403') || error.message?.includes('401')) {
                throw error;
            }
            // 网络超时等不确定错误才降级为成功（Dify 可能已执行删除）
            console.warn('[Dify Chat] 删除会话请求失败，但可能已成功删除:', error.message);
            return { result: 'success' };
        }
    },

    /**
     * 更新消息反馈
     */
    async updateMessageFeedback(
        messageId: string,
        rating: 'like' | 'dislike' | null,
        jwt?: string
    ): Promise<any> {
        const body = {
            rating,
        };

        const response = await difyFetch(`messages/${messageId}/feedbacks`, {
            method: 'POST',
            body: JSON.stringify(body),
        }, jwt);
        return response.json();
    },
};