import { useAppDispatch, useAppSelector } from "@/store";
import { useFocusEffect } from "expo-router";
import { useCallback, useState } from "react";
import { endUploadSessionInDb, syncUploadSessionState } from "@/features/appState/appStateSlice";
import { triggerManualUpload } from "@/lib/background-uploader/automatic";
import { exist_pending_tasks, getUploadTasksSince, UploadTask } from "@/lib/db";

export const useUploadManager = () => {
    const dispatch = useAppDispatch();
    const uploadSessionStartTime = useAppSelector((state) => state.appState.uploadSessionStartTime);
    const [progressInfo, setProgressInfo] = useState({ total: 0, completed: 0, image: '' });

    useFocusEffect(
        useCallback(() => {
            let isActive = true;
            let interval: any = null;

            const manageUploadState = async (restore_session: boolean = false) => {
                if (!isActive) {
                    console.log('useUploadManager manageUploadState is not active');
                    return;
                }

                // 首先，同步Redux中的会话开始时间
                const action = await dispatch(syncUploadSessionState());
                const sessionStartTime = action.payload as number | null;

                if (sessionStartTime) {
                    // 如果会话存在，则获取任务进度
                    const allTasks = await getUploadTasksSince(sessionStartTime);
                    const total = allTasks.length;
                    const completed = allTasks.filter((t: UploadTask) => t.status === 'success' || t.status === 'failed' || t.status === 'skipped').length;
                    const pending = allTasks.filter((t: UploadTask) => t.status === 'pending' || t.status === 'uploading');

                    if (isActive) {
                        setProgressInfo({ total, completed, image: allTasks[0]?.uri || '' });
                    }

                    // 如果任务完成，则结束会话并清除定时器
                    if (total > 0 && pending.length === 0) {
                        console.log('useUploadManager detects all tasks are complete. Ending session.');
                        if (interval) clearInterval(interval);
                        dispatch(endUploadSessionInDb());
                    }
                } else {
                    // 如果没有会话，确保本地状态被重置
                    if (isActive) {
                        setProgressInfo({ total: 0, completed: 0, image: '' });
                    }
                }
            };

            const initializeUploadProcess = async () => {
                // First, check if a session is already active.
                const action = await dispatch(syncUploadSessionState());
                const existingSessionStartTime = action.payload as number | null;
                const existPendingTasks = await exist_pending_tasks();

                if (existingSessionStartTime && existPendingTasks) {
                    console.log('useUploadManager focused, existing session found. Monitoring progress.');
                    // If a session exists, just start monitoring.
                    manageUploadState(true); // Initial check
                    // 将轮询间隔从2秒增加到3秒，减少资源消耗
                    interval = setInterval(manageUploadState, 3000);
                } else {
                    // If no session, then try to trigger a new upload.
                    console.log('useUploadManager focused, no existing session. Triggering foreground media upload check.');
                    const now = new Date();
                    const oneDayAgo = new Date(now.getTime() - 24 * 60 * 60 * 1000);

                    const newSessionStartTimeStr = await triggerManualUpload(oneDayAgo, now);

                    if (newSessionStartTimeStr) {
                        console.log(`New upload session started with time: ${newSessionStartTimeStr}, beginning to monitor...`);
                        // A new session was started, so start monitoring.
                        manageUploadState(); // Initial check
                        // 将轮询间隔从2秒增加到3秒，减少资源消耗
                        interval = setInterval(manageUploadState, 3000);
                    }
                }
            };

            initializeUploadProcess();

            return () => {
                isActive = false;
                if (interval) {
                    clearInterval(interval);
                }
            };
        }, [dispatch])
    );

    return { progressInfo, uploadSessionStartTime };
};