githubcue.js

// Utility function to get "num" random numbers below "limit".
var random_nums = function(limit, num) {
    if (limit > num) {
        limit = num;
    }
    var indices = [Math.floor(Math.random()*num)];
    var i = 1;
    while (i < limit){
        var next = Math.floor(Math.random()*num);
        if (indices.indexOf(next) == -1) {
            indices.push(next);
            i++;
        };
    };
    return indices;
};


// Main entry point
// Fetches all the watched repos of the user and triggers off everything else...
var run = function() {

    // Workaround the lack of access to localStorage ...
    chrome.extension.sendMessage({message: "username"}, function(response) {

        // Globally available
        github = new Github({username: '', password: ''});
        var messages = document.getElementById("interesting_messages");
        messages.textContent = "Fetching interesting repositories. Please Wait...";
        messages.hidden = false;
        var gh_user = github.getUser(),
            watch = gh_user.userWatched(response.username, processDataAndDisplay);
        console.log('Fetching watched repos');
    });
};

// Inserts the html with a message indicating that we are fetching repos.
var insertStubHtml = function(){
    var yrepo = document.getElementById("your_repos"),
        interesting = yrepo.cloneNode(),
        heading = document.createElement("h3"),
        top_bar = document.createElement("div"),
        bottom_bar = top_bar.cloneNode(),
        repo_container = document.createElement("div"),
        repo_list = document.createElement("ul"),
        messages = document.createElement("span"),
        refresh = document.createElement("a");

    messages.id = "interesting_messages";
    messages.textContent = "Fetching interesting repositories. Please Wait...";
    messages.setAttribute('style', 'margin: 1em; top: 0.5em; position: relative');
    repo_container.className = "box-body";
    repo_list.className = "repo-list";
    bottom_bar.className = "bottom-bar";
    heading.textContent = "Interesting Repositories ";
    heading.className = "box-title";
    top_bar.className = "box-header";
    refresh.textContent = 'Refresh';
    refresh.href = "#";
    refresh.setAttribute('style', 'float:right; position:relative; margin: 1em; top: 0.5em;');
    refresh.onclick = function(e) { run() };
    top_bar.appendChild(refresh);
    top_bar.appendChild(heading);
    repo_container.appendChild(repo_list);
    interesting.id = "interest_repos";
    interesting.appendChild(top_bar);
    interesting.appendChild(repo_container);
    interesting.appendChild(messages);
    interesting.appendChild(bottom_bar);

    yrepo.insertAdjacentElement("beforeBegin", interesting);

    if (localStorage.repos) {
        showSuggestions(JSON.parse(localStorage.repos));
    } else {
        run();
    };

}

var setMessage = function(text) {
    messages = document.getElementById("interest_repos");
    messages.textContent = text;
}

// Calls all the functions for processing and displaying ...
var processDataAndDisplay = function( err, repos ) {

    if (err) { setMessage('Failed to fetch interesting repos') };
    var userData = parseRepoData(repos);
    getTags(userData);

};

// Parses the data of all watched repos of the user
// Returns a json object
//     - language : a dict of language name to count of repos
//     - descriptions: a list of all descriptions of repos
var parseRepoData = function(repos) {

    var languages = {},
        descriptions = [];

    repos.forEach( function(elm, i, arr) {

        var repo = repos[i];

        // Get language count for user
        if (arr[i].language) {
            if (arr[i].language in languages) {
                languages[arr[i].language]++;
            } else {
                languages[arr[i].language] = 1;
            }
        }

        // Get descriptions of all the watched repos
        if (arr[i].description) {
            descriptions.push(arr[i].description)
        }
    });

    return {languages: languages, descriptions: descriptions};

};

// Get tags using Yahoo's content analysis service from all the descriptions
// available.  Then passes on the tags for further action to XXX.
var getTags = function(userData) {

    var descriptions = userData.descriptions.join(' ');
    console.log('Getting keywords from descriptions');

    var http = new XMLHttpRequest()
    var url = "http://search.yahooapis.com/ContentAnalysisService/V1/termExtraction";
    var params = "appid=YahooDemo&output=json&context=" + encodeURIComponent(descriptions);
    http.open("POST", url, true);
    http.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    http.onreadystatechange = function() {//Call a function when the state changes.
        if (http.readyState == 4 && http.status == 200) {
            tags = JSON.parse(http.responseText).ResultSet.Result;
            getRepos(userData);
        }
    }

    http.send(params);
}

// Searches for repos using Github's search API
var getRepos = function(userData) {
    console.log('Searching interesting repos based on keywords');
    var interestingRepos = new Array,
        langIndices = random_nums(3, Object.keys(userData.languages).length),
        descripIndices = random_nums(5, tags.length),
        totalCallCount = langIndices.length * descripIndices.length;
        search = github.getSearch(),
        count = 0,
        ourCallBack = function( err, data ) {
            count += 1;
            // Call the callback to insert repos, only if all keyword searches
            // have been done.  Count no. of searches made and compare with
            // total expected number.
            selectInterestingRepos( data, interestingRepos, count == totalCallCount);
        };

    for (i in langIndices) {
        for (j in descripIndices) {
            var language = Object.keys(userData.languages)[langIndices[i]];
            var tag = tags[descripIndices[j]];
            // there should be no undefined tags, but ...
            if (tag==undefined) {tag="github"} else {tag=encodeURIComponent(tag)};
            search.searchRepos(tag, ourCallBack, language);
            // callback();
        }
    }
}

var selectInterestingRepos = function(data, repos, call) {
    for (i in data.repositories.slice(0, 9)) {
        var repo = data.repositories[i];
        if (repos.indexOf(repo) == -1) { repos.push(repo) };
    };
    if (call) { showSuggestions(selectN(repos, 15)) };
}

var selectN = function(sample, count) {
    var indices = random_nums(15, sample.length),
        select = new Array();

    for (i in indices) {
        select.push(sample[indices[i]]);
    };

    return select;
}

var showSuggestions = function(repos) {
    console.log('Displaying suggestions...');
    localStorage.repos = JSON.stringify(repos);
    var node = document.getElementById("interest_repos"),
        messages = document.getElementById("interesting_messages"),
        r_list = node.getElementsByClassName("repo-list")[0],
        repo_list = r_list.cloneNode(),
        old_count = node.getElementsByTagName("em")[0];
        count = document.createElement("em");

    if (old_count) { old_count.parentNode.removeChild(old_count); }

    count.textContent = "(" + repos.length + ")";
    node.getElementsByTagName("h3")[0].appendChild(count);
    node.getElementsByClassName('box-body')[0].replaceChild(repo_list, r_list);

    messages.hidden = true;
    messages.textContent = '';

    for (i in repos) {
        var content = document.createElement("li"),
            link = document.createElement("a"),
            icon = document.createElement("span"),
            owner_and_repo = document.createElement("span"),
            owner = document.createElement("span"),
            name = document.createElement("span"),
            stars = document.createElement("span"),
            stars_icon = document.createElement("span"),
            repo = repos[i];

        if (repo.fork) {
            icon.className = "repo-icon octicon octicon-repo-forked";
        } else {
            icon.className = "repo-icon octicon octicon-repo";
        }
        link.appendChild(icon);
        link.appendChild(owner_and_repo);
        owner_and_repo.className = "repo-and-owner css-truncate-target";
        owner.className = "owner css-truncate-target";
        owner.title = repo.owner;
        owner.textContent = repo.owner+"/";
        owner_and_repo.appendChild(owner);
        name.className = "repo css-truncate-target";
        name.title = repo.name;
        name.textContent = repo.name;
        owner_and_repo.appendChild(name);
        stars.className = 'stars';
        link.appendChild(stars);
        stars.textContent = ' ' + (repo.followers || 0) + ' ';
        stars.appendChild(stars_icon);
        stars_icon.className = "octicon octicon-star";
        link.className = 'repo-list-item css-truncate';
        link.href = repo.url || "/"+repo.owner+"/"+repo.name;
        link.title = repo.description;
        content.className = "public source";
        content.appendChild(link);
        repo_list.appendChild(content);

    }

};

insertStubHtml();