/** express app for routing */
const express = require("express");

/**session data for login and storing preferences*/
const session = require('express-session');

const fileIO = require('./fileIO');

const userUtils = require('./user.js');

const configLoader = require('./configManager.js');

const recursive = require('./recursiveTraversal');

const filepreview = require('filepreview');

const fs = require('fs');





const app = express();

/**Initializes sessions for login */
app.use(session({ secret: configLoader.getConfiguration().sessionSecret, cookie: { maxAge: 6000000 }}));

app.use(express.urlencoded());
app.use(express.json());      // if needed

const routes = require('./routes');
app.use('/', routes);




// const CONFIG_FILE_NAME = "conf.json";
// const config = fileIO.getFileAsJSON(CONFIG_FILE_NAME);



// /** Template engine */
// const whiskers = require('whiskers');

var rootDir = '/home/jeff/work/aaSchool/Algo/online Lectures/';

var serverURL = "http://localhost:5000";

// function fetchInTemplate(templateContext, templateKey, filename)
// {
//     templateContext[templateKey] = fileIO.getFile(filename);
// }

// function renderHTML(request, result, templateFile, templateDependencyFunction)
// {
//     var templateContext = Object();
//     var prom = [];
//
//     prom.push(fileIO.getFile("./html/mainTemplate.html"));
//     prom.push(fetchInTemplate(templateContext, "header", "./html/header.html"));
//     prom.push(fetchInTemplate(templateContext, "footer", "./html/footer.html"));
//     if(checkPrivilege(request) >= PRIVILEGE.MEMBER)
//     {
//         templateContext.loggedIn = true;
//         if(checkPrivilege(request) === PRIVILEGE.ADMIN)
//             templateContext.admin = true;
//         if(templateDependencyFunction !== null)
//             prom.push(templateDependencyFunction(templateContext, request));
//         prom.push(fetchInTemplate(templateContext, "main","./html/" + templateFile));
//     }
//     else
//     {
//         prom.push(fetchInTemplate(templateContext, "login","./html/login.html"));
//     }
//
//     Promise.all(prom).then(function(content)
//     {
//         result.write(whiskers.render(content[0], templateContext));
//         result.end();
//     });
// }

// function getUserInformation(templateContext, request)
// {
//     templateContext.users = configLoader.getConfiguration().users;
//     templateContext.apiKey = request.session.API;
//     templateContext.id = request.session.userID;
//     templateContext.username = request.session.username;
// }

// function getHomePageInformation(templateContext, request)
// {
//     templateContext.username = request.session.username;
// }

// app.get('/', (req, res) => renderHTML(req, res, "home.html", getHomePageInformation));
// app.get('/users', (req, res) => renderHTML(req, res, "users.html", getUserInformation));

app.use(express.static('css'));
app.use(express.static('js'));
app.use(express.static('img'));



var videos = null;

function getVideosTemplateInformation(templateContext, request)
{
    if(videos === null)
    {
        videos = [];
        return new Promise(function(resolve, reject)
        {
            recursive(rootDir, function (err, files)
            {
                console.log(files);
                files.forEach(file =>
                {
                    var splitArray = file.split('/');
                    var name = splitArray[splitArray.length -1];
                    const icon = 'img/private/' + name + ".png";
                    if (!fs.existsSync(icon))
                    {
                        filepreview.generate(file, icon, function(error) {
                            if (error) {
                                return console.log(error);
                            }
                            console.log('File preview is located ' + icon);
                        });
                    }
                    videos.push({name: file.replace(rootDir, ''), length: "n/a"});
                });
                templateContext.videos = videos;
                resolve();
            });
        })
    }
    else
    {
        templateContext.videos = videos;
    }
}

function getVideoTemplateInfo(templateContext, request)
{
    templateContext.api = request.session.API;
    templateContext.serverURL = serverURL;
    templateContext.videoURL = request.query.v.split(" ").join("%20");
}

// app.get('/videos', (req, res) => renderHTML(req, res, "videos.html", getVideosTemplateInformation));
// app.get('/watch', (req, res) => renderHTML(req, res, "watch.html", getVideoTemplateInfo));


function isPublicVideo(videoURL)
{
    return false;
}


app.get('/icon/', function(request, result)
{
    try
    {
        const videoID = request.query.v;

        const splitArray = videoID.split('/');
        const name = splitArray[splitArray.length -1] + ".png";

        var file="";

        if(!isPublicVideo(videoID))
        {
            if(checkPrivilege(request) >= PRIVILEGE.MEMBER)
            {
                file = fs.readFileSync("img/private/" + name);
            }
            else
            {
                throw "Not logged in";
            }
        }
        else
        {
            file = fs.readFileSync("img/public/" + name);
        }

        result.writeHead(200, {'Content-Type': 'image/png',
            'Vary': 'Accept-Encoding'});
        result.write(file);
        result.end();
    }
    catch(error)
    {
        result.writeHead(404, {'Content-Type': 'text/html',
            'Vary': 'Accept-Encoding'});
        result.write("Nada");
        result.end();
    }
});

app.get('/video/', function(request, result)
{
    if(checkPrivilege(request) >= PRIVILEGE.MEMBER || userUtils.isValidAPI(request.query.api, config))
    {
        var videoID = request.query.v;
        const path = rootDir + videoID;
        const stat = fs.statSync(path);
        const fileSize = stat.size;
        const range = request.headers.range;

        if (range)
        {
            const parts = range.replace(/bytes=/, "").split("-");
            const start = parseInt(parts[0], 10);
            const end = parts[1]
                ? parseInt(parts[1], 10)
                : fileSize-1;

            const chunksize = (end-start)+1;
            const file = fs.createReadStream(path, {start, end});
            const head =
                {
                    'Content-Range': `bytes ${start}-${end}/${fileSize}`,
                    'Accept-Ranges': 'bytes',
                    'Content-Length': chunksize,
                    'Content-Type': 'video/mp4',
                };
            result.writeHead(206, head);
            file.pipe(result);
        }
        else
        {
            const head =
                {
                    'Content-Length': fileSize,
                    'Content-Type': 'video/mp4',
                };

            result.writeHead(200, head);
            fs.createReadStream(path).pipe(result);
        }
    }
    else
    {
        console.log("invalid attempt to view video");
        result.status(401);
        result.send('None shall pass');
    }
});


// app.post('/revokeAPI', function(request, result)
// {
//     if(checkPrivilege(request) === PRIVILEGE.ADMIN)
//     {
//         userUtils.revokeAPI(request.body.username, config);
//         request.session.API = userUtils.getAPIKEY(request.session.username, config);
//         fileIO.writeJSONToFile(CONFIG_FILE_NAME, config);
//     }
//     else if (checkPrivilege(request) === PRIVILEGE.MEMBER)
//     {
//         userUtils.revokeAPI(request.session.username, config);
//         request.session.API = userUtils.getAPIKEY(request.session.username, config);
//         fileIO.writeJSONToFile(CONFIG_FILE_NAME, config);
//     }
//     result.redirect('/users');
// });


// app.post('/addUser', function(request, result)
// {
//     if(checkPrivilege(request) === PRIVILEGE.ADMIN)
//     {
//         console.log(request.body);
//         var admin = false;
//         if(request.body.admin === 'on')
//             admin = true;
//         userUtils.addUser(request.body.username, request.body.password,admin, config);
//         fileIO.writeJSONToFile(CONFIG_FILE_NAME, config);
//         result.redirect('/users');
//     }
//     else
//     {
//         result.status(401);
//         result.send('None shall pass');
//     }
// });


// app.post('/edituser', function(request, result)
// {
//     if(checkPrivilege(request) === PRIVILEGE.ADMIN)
//     {
//         var admin = false;
//         if(request.body.admin === 'on')
//             admin = true;
//         userUtils.editUser(request.body.id, request.body.username, request.body.password,admin, config);
//         fileIO.writeJSONToFile(CONFIG_FILE_NAME, config);
//         result.redirect('/users');
//     }
//     else
//     {
//         result.status(401);
//         result.send('None shall pass');
//     }
// });


// app.post('/updateUser', function(request, result)
// {
//     if(checkPrivilege(request) >= PRIVILEGE.MEMBER)
//     {
//         console.log(request.session.userID);
//         var admin = false;
//         userUtils.editUser(request.session.userID, request.body.username, request.body.password,admin, config);
//         fileIO.writeJSONToFile(CONFIG_FILE_NAME, config);
//         result.redirect('/users');
//     }
//     else
//     {
//         result.status(401);
//         result.send('None shall pass');
//     }
// });

// const PRIVILEGE = {NOBODY: 0, MEMBER: 1, ADMIN: 2};
// const checkPrivilege = function(request)
// {
//     if(request.session.login !== true)
//         return PRIVILEGE.NOBODY;
//     else if(request.session.admin === true)
//         return PRIVILEGE.ADMIN;
//     return PRIVILEGE.MEMBER;
// };

// app.post('/removeuser', function(request, result)
// {
//     if(checkPrivilege(request) === PRIVILEGE.ADMIN)
//     {
//         userUtils.removeUser(request.body.id, config);
//         fileIO.writeJSONToFile(CONFIG_FILE_NAME, config);
//         result.redirect('/users');
//     }
//     else
//     {
//         result.status(401);
//         result.send('None shall pass');
//     }
// });

// app.post('/logout', function(request, result)
// {
//     request.session.login = false;
//     request.session.admin = false;
//     result.redirect('/');
// });



// app.post('/login', function(request, result)
// {
//     if(userUtils.checkLogin(request.body.username, request.body.password, config))
//     {
//         request.session.login = true;
//         request.session.username = request.body.username;
//         request.session.userID = userUtils.getID(request.body.username, config);
//         request.session.API = userUtils.getAPIKEY(request.body.username, config);
//         if(userUtils.isAdmin(request.body.username, config))
//         {
//             request.session.admin = true;
//         }
//     }
//     result.redirect('/');
// });


app.listen(configLoader.getConfiguration().port, () => console.log(`App listening on port ${configLoader.getConfiguration().port}!`));