GitHub Explained in OOP

simplified_github.js

class Git {

    constructor(name) {
        this.name = name;
        this.lastCommitId = -1;
        this.branches = [];

        var master = new Branch("master, null");
        this.branches.push(master);
        this.Head = master;
    }

    commit(message) {
        var commit = new Commit(++this.lastCommitId, this.Head.commit, message);
        this.Head.commit = commit
        return commit;
    }

    log() {
        var commit = this.Head.commit, history = [];

        while (commit) {
            history.push(commit);
            // Keep following the parent
            commit = commit.parent;
        }

        return history;
    }

    checkout(branch_name){
        for(var i = this.branches.length; i--;){
            if(this.branches[i].name === branch_name){
                console.log("Switching to existing branch: " + branch_name);
                this.Head = this.branches[i];
                return this;
            }
        }

        var new_branch = new Branch(branch_name, this.Head.commit);
        this.branches.push(new_branch);
        this.Head = new_branch;

        console.log("switched to new branch: " + branch_name);
        return this;
    }
}



class Commit {
    constructor(id, parent, message) {
        this.id = id;
        this.parent = parent;
        this.message = message;
    }
}



class Branch {

    constructor(name, commit) {
        this.name = name;
        this.commit = commit;
    }



}


// git init
var repo = new Git("my-repo");