load-scripts.js

// { name: dependencies, ... }
var scripts = {
    s1: ["s2", "s3"],
    s2: ["s3", "s4", "s5"],
    s3: ["s4"],
    s4: [],
    s5: []
}

var scriptsLoadStarted = { };
var scriptsExecuted = { };
var scriptsDependencies = { };

var loadScript = function(name, callback) {
    scriptsLoadStarted[name] = true;
    setTimeout(function () { callback(name, scripts[name]); }, 1000);
}

var executeScript = function (name) {
    console.log(name + " executed!");
    scriptsExecuted[name] = true;
    
    for (var m in scriptsDependencies) {
        var dependencies = scriptsDependencies[m];
        var index = dependencies.indexOf(name);
        if (index >= 0) {
            dependencies.splice(index, 1);
            if (dependencies.length <= 0) {
                executeScript(m);
            }
        }
    }
}

var loadScriptCallback = function (name, dependencies) {
    scriptsDependencies[name] = [];
    console.log(name + " loaded!");
    
    for (var i = 0; i < dependencies.length; i++) {
        var d = dependencies[i];
        if (!scriptsExecuted[d]) {
            scriptsDependencies[name].push(d);
            if (!scriptsLoadStarted[d]) {
                loadScript(d, loadScriptCallback);
            }
        }
    }
    
    if (scriptsDependencies[name].length <= 0) {
        executeScript(name);
    }
}

loadScript("s1", loadScriptCallback);