You'll need to create a screeps.json file in the root of the project and add in your own token generated from your Screeps account. A screeps.example.json has been added to the project as a template.
Next, open a terminal at the root of this project and run npm install to install the dependencies.
The code is located in the src folder. To upload it to the Screeps server, run npm run push in the terminal.
Screeps uses NodeJS as its runtime, but it has a few limitations if you're using the IDE in the game. Mainly, it doesn't support import or export statements, and doesn't support nested directories. Here, we're using a bundler to give us the ability to write javascript in the way we know and love, and it will compile it into the dist folder when uploading to the Screeps server.
This configuration does support TypeScript, but I'm not currently using it. I'm still in the process of changing my codebase rapidly while learning the game, and I don't want to have to worry about updating the types as I go. I may switch to TypeScript in the future, but for now I'm sticking with plain old JavaScript.
When brainstorming and looking through existing code-bases for Screeps, I saw how most people were creating enormous chains of logic through several nested functions. It was difficult for me to keep track of what was going on, and I wanted to a way to make it easier to understand and maintain. Using contextually named classes, I've been able to break down the logic into smaller, more manageable chunks, and build on seperate logic paths without "getting lost in the sauce".
While functional programming can be more efficient with CPU usage, an object oriented programming approach is a worthwhile trade-off for the readability and maintainability of the code.
The main loop is the core of the game. It's where all of the logic is executed, and where the game state is updated. Each "game tick", the game calls the loop function in main.js, which is where we'll be putting all of our code. I try to keep the loop function as clean as possible, and instantiate classes to handle the logic for each part of the game.
The spawn controller is a class that represents a single spawn point. It's responsibility is to monitor and evaluate different aspects of the room it's in, handle the logic for spawning new creeps, and includes logic for each new creep's loadout based on the room's energy capacity.
Creeps are the units that you control in the game. They can be assigned different roles, and each role has a different set of responsibilities. For example, a harvester's job is to harvest energy from a source. A hauler's job is to move energy from sources to different assets that need it. A builder's job is to build structures in the room. An upgrader's job is to continuously provide energy to upgrade the room. Each role has a class that handles the logic for that role.
Additionally, all of these roles extend the CreepBase class, where I've put all of the logic that is common to all creeps. This includes things like moving to a target, gathering energy, etc. Any time I require repeating code between roles, I move it to the CreepBase class to make it more maintainable.
As I've been building out the different roles and testing their efficiency, I saw a need for a controller that would help manage them more collectively. The CreepsController class is used for any logic that needs to be shared between all creeps, or between multiple creeps. For example, I use it to assign a designated source to each harvester, so that they don't all try to harvest from the same source. I also use it to assign a designated target to each hauler, so that they don't all try to move energy from the same target.