import type { BackgroundCommand, BackgroundResponse, CrawlStateResponse } from '../types';
import {
    cancelAutoclose,
    cancelCrawl,
    cancelCrawlWhenWindowRemoved,
    cancelStaleCrawlWhenWindowMissing,
    dismissCrawl,
    resumeCrawl,
    startCrawl,
} from './crawlTask';
import { getCrawlTaskState } from './taskState';

/**
 * 扩展安装完成时的初始化入口，当前仅保留日志方便调试生命周期。
 */
export async function handleInstalled(): Promise<void> {
    console.log('[background] installed');
}

/**
 * 浏览器启动并加载扩展时的初始化入口，当前仅保留日志方便调试生命周期。
 */
export async function handleStartup(): Promise<void> {
    console.log('[background] startup');
    await cancelStaleCrawlWhenWindowMissing();
}

/**
 * 监听窗口关闭事件；如果关闭的是爬取窗口，就把当前任务标记为取消。
 */
export async function handleWindowRemoved(windowId: number): Promise<void> {
    console.log('[background] window removed', windowId);
    await cancelCrawlWhenWindowRemoved(windowId);
}

/**
 * 根据 popup/content 发来的 action 分发到对应的后台处理函数。
 */
export async function handleBackgroundCommand(
    message: BackgroundCommand,
): Promise<BackgroundResponse | CrawlStateResponse> {
    switch (message.action) {
        case 'START_CRAWL':
            return startCrawl(message.payload.platformId);
        case 'GET_CRAWL_STATE':
            await cancelStaleCrawlWhenWindowMissing();
            return { ok: true, data: await getCrawlTaskState() };
        case 'CANCEL_CRAWL':
            return cancelCrawl();
        case 'RESUME_CRAWL':
            return resumeCrawl();
        case 'CANCEL_AUTOCLOSE':
            return cancelAutoclose();
        case 'DISMISS_CRAWL':
            return dismissCrawl();
        default:
            return { ok: false, error: '未知的后台指令' };
    }
}