// background 虽然天然可以跨域，然而既然是后台就没有 cookie 的概念，即使 fetch 设置了 credentials, cookie 依然不会被保存  
// http://stackoverflow.com/questions/29251842/why-new-js-fetch-standard-forbid-response-header-name-as-set-cookie-1-2  

// const { createFFmpeg, fetchFile } = FFmpeg;

// async function test(){
//     const ffmpeg = createFFmpeg({log: true});
//     await ffmpeg.load();
//     console.log(ffmpeg);
// };

// test();

const videos = {};
window.videos = videos;

/**
 *  data: fr.result,
    size: blobData.size,
    mimeType: blobData.type,
    name: document.title,
    action: 'data'
 */
chrome.runtime.onMessage.addListener((msg, sender, sendResponse) => {
    // console.log("Received %o from %o, frame", msg, sender.tab, sender.frameId);
    sendResponse("Gotcha!");

    if(msg.action === 'end'){
        return download(sender.documentId);
    }

    if(!msg.data || msg.size !== msg.data.length){
        return console.warn('data received error: ', msg.name);
    }

    const blobAsBinString = msg.data;
    const bytes = new Uint8Array(blobAsBinString.length);
    for(let i=0,len=blobAsBinString.length; i<len; i++){
        bytes[i] = blobAsBinString.charCodeAt(i);
    }
    videos[sender.documentId] = videos[sender.documentId] || {};
    videos[sender.documentId].blob = videos[sender.documentId].blob || [];
    videos[sender.documentId].mimeType = msg.mimeType;
    videos[sender.documentId].name = msg.name;
    videos[sender.documentId].blob.push(bytes);
});

function download(id){
    const tar = videos[id];
    if(!tar){
        return ;
    }
    const blob = new Blob(tar.blob, {type: tar.mimeType});
    const ext = tar.mimeType.includes('webm') ? 'webm' : 'mkb';
    const filename = `${tar.name || 'anonymous'}.${ext}`;
    chrome.downloads.download({
        url: URL.createObjectURL(blob),
        filename
    }, resp => {
        delete videos[id];
    });
};

// chrome.webNavigation.onCompleted
chrome.webNavigation.onBeforeNavigate.addListener(frame => {
    // chrome.webNavigation.getFrame({
    //     frameId: frame.frameId,
    //     tabId: frame.tabId
    // }, details => {
    //     alert(JSON.stringify(details));
    // });
});

// chrome.tabs.onUpdated.addListener(function(tabId, changeInfo, tab) {
    // chrome.webNavigation.getAllFrames({tabId: tabId}, function(details) {
    //     details.forEach(function(frame) {
    //         console.log(tabId);
    //         // chrome.tabs.sendMessage(
    //         //     tabId,
    //         //     {text: 'hey_cs'},
    //         //     {frameId: frame.frameId},
    //         //     function(response) { console.log(response) }
    //         // );
    //     });
    // });
// });