package com.ycwl.basic.controller.mobile;

import com.ycwl.basic.model.jwt.JwtInfo;
import com.ycwl.basic.model.mobile.chat.*;
import com.ycwl.basic.service.mobile.FaceChatService;
import com.ycwl.basic.utils.ApiResponse;
import com.ycwl.basic.utils.JwtTokenUtil;
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.servlet.mvc.method.annotation.ResponseBodyEmitter;

import java.util.concurrent.CompletableFuture;

/**
 * 小程序人脸智能聊天接口。
 */
@Slf4j
@RestController
@RequestMapping("/api/mobile/chat/v1")
@RequiredArgsConstructor
public class AppChatController {

    private final FaceChatService faceChatService;

    /**
     * 获取或创建会话（同一人脸只保留一条）。
     */
    @PostMapping("/faces/{faceId}/conversation")
    public ApiResponse<ChatConversationVO> createConversation(@PathVariable Long faceId) {
        JwtInfo worker = JwtTokenUtil.getWorker();
        ChatConversationVO vo = faceChatService.getOrCreateConversation(faceId, worker.getUserId());
        return ApiResponse.success(vo);
    }

    /**
     * 同步发送消息，适用于短回复或前端自行轮询。
     */
    @PostMapping("/conversations/{conversationId}/messages")
    public ApiResponse<ChatSendMessageResp> sendMessage(@PathVariable Long conversationId,
                                                        @RequestBody ChatSendMessageReq req) {
        JwtInfo worker = JwtTokenUtil.getWorker();
        ChatSendMessageResp resp = faceChatService.sendMessage(conversationId, worker.getUserId(),
                req.getContent(), req.getTraceId());
        return ApiResponse.success(resp);
    }

    /**
     * 流式返回，使用 HTTP chunked。小程序侧用 wx.request 的 onChunkReceived 消费。
     */
    @PostMapping(value = "/conversations/{conversationId}/messages/stream", produces = "text/plain;charset=UTF-8")
    public ResponseBodyEmitter streamMessage(@PathVariable Long conversationId,
                                             @RequestBody ChatSendMessageReq req) {
        JwtInfo worker = JwtTokenUtil.getWorker();
        ResponseBodyEmitter emitter = new ResponseBodyEmitter(30_000L);
        CompletableFuture.runAsync(() -> {
            try {
                faceChatService.sendMessageStream(
                        conversationId,
                        worker.getUserId(),
                        req.getContent(),
                        req.getTraceId(),
                        chunk -> {
                            try {
                                emitter.send(chunk, new MediaType("text", "plain", java.nio.charset.StandardCharsets.UTF_8));
                            } catch (Exception e) {
                                emitter.completeWithError(e);
                            }
                        });
                emitter.complete();
            } catch (Exception e) {
                log.error("streamMessage error", e);
                emitter.completeWithError(e);
            }
        });
        return emitter;
    }

    /**
     * 查询历史消息，cursor 为最后一条 seq，limit 为条数。
     */
    @GetMapping("/conversations/{conversationId}/messages")
    public ApiResponse<ChatMessagePageResp> listMessages(@PathVariable Long conversationId,
                                                         @RequestParam(value = "cursor", required = false) Integer cursor,
                                                         @RequestParam(value = "limit", required = false) Integer limit) {
        JwtInfo worker = JwtTokenUtil.getWorker();
        ChatMessagePageResp resp = faceChatService.listMessages(conversationId, cursor, limit, worker.getUserId());
        return ApiResponse.success(resp);
    }

    @PostMapping("/conversations/{conversationId}/close")
    public ApiResponse<String> closeConversation(@PathVariable Long conversationId) {
        JwtInfo worker = JwtTokenUtil.getWorker();
        faceChatService.closeConversation(conversationId, worker.getUserId());
        return ApiResponse.success("OK");
    }
}