var Hipchat = require('node-hipchat'),
    path = require("path"),
    assert = require("assert"),
    fs = require("fs-extra"),
    glob = require("glob"),
    _ = require('lodash'),
    request = require("superagent"),
    async = require("async"),
    tarball = require('tarball-extract'),
    colors = require('colors')

colors.setTheme({
  prompt: 'cyan',
  info: 'grey',
  success: 'green',
  warn: 'yellow',
  error: 'red'
});

var HC = new Hipchat(process.env.HIPCHAT);
var hipchat = {
  message: function(color, message) {
    if (process.env.HIPCHAT) {
      var params = {
        room: 165440,
        from: 'Auto Update',
        message: message,
        color: color,
        notify: 0
      };
      HC.postMessage(params, function(data) {});
    } else {
      console.log('No Hipchat API Key'.warn);
    }
  }
};

hipchat.message('gray', 'Auto Update Started');
var newVersionCount = 0;
var parse = function (json_file, ignore_missing, ignore_parse_fail) {
    var content;

    try {
        content = fs.readFileSync(json_file, 'utf8');
    } catch (err1) {
        if (!ignore_missing) {
            assert.ok(0, json_file + " doesn't exist!");
        }
        return null;
    }
    try {
        return JSON.parse(content);
    } catch (err2) {
        if (!ignore_parse_fail) {
            //assert.ok(0, json_file + " failed to parse");
        }
        return null;
    }
}

var reEscape = function(s){
    return s.replace(/[-\/\\^$*+?.()|[\]{}]/g, '\\$&');
}

/**
 * Check if an npmFileMap object contains any path which are not normalized, and thus could allow access to parent dirs
 * @param pkg
 * @returns {*}
 */
var isValidFileMap = function(pkg){
    var isValidPath = function(p){
        if(p !== null){ //don't allow parent dir access, or tricky paths
            p = p.replace(/\/+/g, '/'); //dont penalize for consequtive path seperators
            return p === path.normalize(p);
        }
        return false
    };

    if(pkg && pkg.npmFileMap){
        return _.every(pkg.npmFileMap, function(fileSpec){
           if(isValidPath(fileSpec.basePath || "/")){
               return _.every(fileSpec.files, isValidPath);
           }
           return false;
        });
    }
    return false
};

var error = function(msg, name){
    var err = new Error(msg);
    err.name = name;
    console.log(msg.error);
    hipchat.message('red', msg);
    return err;
}
error.PKG_NAME = 'BadPackageName'
error.FILE_PATH = 'BadFilePath'

/**
 * returns a fucntion that takes N args, where each arg is a path that must not outside of libPath.
 * returns true if all paths are within libPath, else false
 */
var isAllowedPathFn = function(libPath){ //is path within the lib dir? if not, they shouldnt be writing/reading there
    libPath = path.normalize(libPath || "/");
    return function(){
        var paths = 1 <= arguments.length ? [].slice.call(arguments, 0) : [];
        var re = new RegExp("^"+reEscape(libPath));
        return _.every(paths, function(p) {
            p = path.normalize(p);
            return p.match(re);
        });
    }
};

var invalidNpmName = function(name){
    return !!~name.indexOf(".."); //doesnt contain
}

/**
 * Attempt to update the npmFileMap from extracted package.json, then using npmFileMap move required files to libPath/../
 * If the npmFileMap tries to modify files outside of libPath, dont let it!
 * @param pkg
 * @param libPath = root folder for extracted lib
 * @returns {Array} = array of security related errors triggered during operation.
 */
var processNewVersion = function(pkg, version){
    //sometimes the tar is extracted to a dir that isnt called 'package' - get that dir via glob
    var extractLibPath = glob.sync(getPackageTempPath(pkg, version)+"/*/")[0];

    if(!extractLibPath){
      //even more rarely, the tar doesnt seem to get extracted at all.. which is probably a bug in that lib.
      var msg = pkg.npmName + "@" + version + " - never got extracted! This problem usually goes away on next run. Couldnt find extract dir here: " + getPackageTempPath(pkg, version);
      console.log(msg.error);
      return;
    }
    var libPath = getPackagePath(pkg, version)

    var isAllowedPath = isAllowedPathFn(extractLibPath);

    var newPath = path.join(libPath, 'package.json')
    if(false && fs.existsSync(newPath)){ //turn this off for now
        var newPkg = parse(newPath);
        if(isValidFileMap(newPkg)){
            pkg.npmFileMap = newPkg.npmFileMap;
        }
    }
    var npmFileMap = pkg.npmFileMap;
    var errors = [];

    var updated = false;

    _.each(npmFileMap, function(fileSpec) {
        var basePath = fileSpec.basePath || "";

        _.each(fileSpec.files, function(file) {
            var libContentsPath = path.normalize(path.join(extractLibPath, basePath));
            if(!isAllowedPath(libContentsPath)){
                errors.push(error(pkg.npmName+" contains a malicious file path: "+libContentsPath, error.FILE_PATH));
                return
            }
            var files = glob.sync(path.join(libContentsPath, file));
            var copyPath = path.join(libPath, basePath)

            if(files.length == 0){
              //usually old versions have this problem
              var msg = (pkg.npmName + "@" + version + " - couldnt find file in npmFileMap.") + (" Doesnt exist: " + path.join(libContentsPath, file)).info;
              console.log(msg);
            }

            _.each(files, function(extractFilePath) {
                if(extractFilePath.match(/(dependencies|\.zip\s*$)/i)){
                  return;
                }

                var copyPart = path.relative(libContentsPath, extractFilePath);
                var copyPath = path.join(libPath, copyPart)
                fs.mkdirsSync(path.dirname(copyPath))
                fs.renameSync(extractFilePath, copyPath);
                updated = true;
            });
        });
    });
    if(updated){
      newVersionCount++;
        var libPatha =path.normalize(path.join(__dirname, 'ajax', 'libs', pkg.name, 'package.json'));
        console.log('------------'.red, libPatha.green);    
        pkg.version = version;

        fs.writeFileSync(libPatha, JSON.stringify(pkg, null, 2) + '\n', 'utf8');
    }
    return errors;
}


var getPackageTempPath = function(pkg, version){
    return path.normalize(path.join(__dirname, 'temp', pkg.name, version))
}
var getPackagePath = function(pkg, version){
    return path.normalize(path.join(__dirname, 'ajax', 'libs', pkg.name, version));
}
/**
 * download and extract a tarball for a single npm version, get the files in npmFileMap and delete the rest
 * @param pkg
 * @param tarballUrl
 * @param version
 * @param cb
 * @returns {*}
 */
var updateLibraryVersion = function(pkg, tarballUrl, version, cb) {
    if(invalidNpmName(pkg.name)){
        return cb(error(pkg.npmName+" has a malicious package name:"+ pkg.name, error.PKG_NAME));
    }
    var extractLibPath = getPackageTempPath(pkg, version);
    var libPath = getPackagePath(pkg, version);


    if(!fs.existsSync(libPath)) {
        fs.mkdirsSync(extractLibPath);
        var url = tarballUrl;
        var downloadFile = path.join(extractLibPath, 'dist.tar.gz');
        tarball.extractTarballDownload(url , downloadFile, extractLibPath, {}, function(err, result) {
            if(fs.existsSync(downloadFile)){
                processNewVersion(pkg, version);
                var msg = "Do not have version " + version + " of " + pkg.npmName;
                console.log(msg.warn);
            } else {
                var msg = "error downloading " + version + " of " + pkg.npmName + " it didnt exist: " + result + err;
                console.log(msg.error);
            }
            cb()
        });
    } else {
        cb()
    }
};

/**
 * grab all versions of a lib that has an 'npmFileMap' and 'npmName' in its package.json
 * @param pkg
 * @param tarballUrl
 * @param cb
 */
var updateLibrary = function (pkg, cb) {
    if(!isValidFileMap(pkg)){
        var msg = pkg.npmName.error + " has a malicious npmFileMap";
        console.log(msg.warn);
        hipchat.message('red', pkg.npmName+" has a malicious npmFileMap: "+ JSON.stringify(pkg.npmFileMap));
        return cb(null);
    }
    var msg = 'Checking versions for ' + pkg.npmName;
    console.log(msg);
    request.get('http://registry.npmjs.org/' + pkg.npmName, function(result) {
        async.eachLimit(_.pairs(result.body.versions), maxWorker, function(p, cb){
            var data = p[1];
            var version = p[0];
            updateLibraryVersion(pkg, data.dist.tarball, version, cb)
        }, function(err){
        var msg = 'Library finished' + (err ? ' ' + err.error : '');
        console.log(msg);
            cb(null);
        });
    });
}

exports.run = function(){
    fs.removeSync(path.join(__dirname, 'temp'))

    process.on('uncaughtException', function(){
      fs.removeSync(path.join(__dirname, 'temp'))
    })
    console.log('Looking for npm enabled libraries...');

    // load up those files
    var packages = glob.sync("./ajax/libs/*/package.json");
    packages = _(packages).map(function (pkg) {
        var parsedPkg = parse(pkg);
        return (parsedPkg.npmName && parsedPkg.npmFileMap) ? parsedPkg : null;
    }).compact().value();
    hipchat.message('green', 'Found ' + packages.length + ' npm enabled libraries');
    var msg = 'Found ' + packages.length + ' npm enabled libraries';
    console.log(msg.prompt);

    async.eachLimit(packages, maxWorker, updateLibrary, function(err) {
        var msg = 'Auto Update Completed - ' + newVersionCount + ' versions were updated';
        console.log(msg.prompt);
        hipchat.message('green', 'Auto Update Completed - ' + newVersionCount + ' versions were updated');
        fs.removeSync(path.join(__dirname, 'temp'))
    });
}
exports.updateLibrary = updateLibrary;
exports.updateLibraryVersion = updateLibraryVersion;
exports.processNewVersion = processNewVersion;
exports.error = error;
exports.isAllowedPathFn = isAllowedPathFn;
exports.isValidFileMap = isValidFileMap;
exports.invalidNpmName = invalidNpmName;


var args = process.argv.slice(2);
if(args.length > 0 && args[0] == 'run'){
    maxWorker = (args[1] == 'serial') ? 1 : 8;
    exports.run()
} else {
    console.log('to start, pass the "run" arg'.prompt)
}