CC-Tweaked/projects/web/ARCHITECTURE.md

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# Architecture
As mentioned in the main architecture guide, the web subproject is responsible for building CC: Tweaked's documentation
website. This is surprisingly more complex than one might initially assume, hence the need for this document at all!

## Web-based emulator
Most of the complexity comes from the web-based emulator we embed in our documentation. This uses [TeaVM] to compile
CC: Tweaked's core to Javascript, and then call out to it in the main site.

The code for this is split into three separate components:
 - `src/main`: This holds the emulator itself: this is a basic Java project which depends on CC:T's core, and exposes an
   interface for Javascript code.

   Some of our code (or dependencies) cannot be compiled to Javascript, for instance most of our HTTP implementation. In
   theses cases we provide a replacement class. These classes start with `T` (for instance `THttpRequest`), which are
   specially handled in the next step.

 - `src/builder`: This module consumes the above code and compiles everything to Javascript using TeaVM. There's a
    couple of places where we need to patch the bytecode before compiling it, so this also includes a basic ASM
    rewriting system.

 - `src/frontend`: This consumes the interface exposed by the main emulator, and actually embeds the emulator in the
   website.

## Static content
Rendering the static portion of the website is fortunately much simpler.

 - Doc generation: This is mostly handled in various Gradle files. The Forge Gradle script uses [cct-javadoc] to convert
   Javadoc on our peripherals and APIs to LDoc/[illuaminate] compatible documentation. This is then fed into illuaminate
   which spits out HTML.

 - `src/htmlTransform`: We do a small amount of post-processing on the HTML in order. This project does syntax
   highlighting of non-Lua code blocks, and replaces special `<mc-recipe>` tags with a rendered view of a given
   Minecraft recipe.

[TeaVM]: https://github.com/konsoletyper/teavm "TeaVM - Compiler of Java bytecode to JavaScript"
[cct-javadoc]: https://github.com/cc-tweaked/cct-javadoc: "cct-javadoc - A Javadoc doclet to extract documentation from @LuaFunction methods."
[illuaminate]: https://github.com/Squiddev/illuaminate: "illuaminate - Very WIP static analysis for Lua"
Build a web-based emulator for the documentation site (#1597) Historically we've used copy-cat to provide a web-based emulator for running example code on our documentation site. However, copy-cat is often out-of-date with CC:T, which means example snippets fail when you try to run them! This commit vendors in copy-cat (or rather an updated version of it) into CC:T itself, allowing us to ensure the emulator is always in sync with the mod. While the ARCHITECTURE.md documentation goes into a little bit more detail here, the general implementation is as follows - In project/src/main we implement the core of the emulator. This includes a basic reimplementation of some of CC's classes to work on the web (mostly the HTTP API and ComputerThread), and some additional code to expose the computers to Javascript. - This is all then compiled to Javascript using [TeaVM][1] (we actually use a [personal fork of it][2] as there's a couple of changes I've not upstreamed yet). - The Javascript side then pulls in the these compiled classes (and the CC ROM) and hooks them up to [cc-web-term][3] to display the actual computer. - As we're no longer pulling in copy-cat, we can simplify our bundling system a little - we now just compile to ESM modules directly. [1]: https://github.com/konsoletyper/teavm [2]: https://github.com/SquidDev/teavm/tree/squid-patches [3]: https://github.com/squiddev-cc/cc-web-term 2023-10-03 08:19:19 +00:00			`<!--`
			`SPDX-FileCopyrightText: 2023 The CC: Tweaked Developers`

			`SPDX-License-Identifier: MPL-2.0`
			`-->`

			`# Architecture`
			`As mentioned in the main architecture guide, the web subproject is responsible for building CC: Tweaked's documentation`
			`website. This is surprisingly more complex than one might initially assume, hence the need for this document at all!`

			`## Web-based emulator`
			`Most of the complexity comes from the web-based emulator we embed in our documentation. This uses [TeaVM] to compile`
			`CC: Tweaked's core to Javascript, and then call out to it in the main site.`

			`The code for this is split into three separate components:`
			- `src/main`: This holds the emulator itself: this is a basic Java project which depends on CC:T's core, and exposes an
			`interface for Javascript code.`

			`Some of our code (or dependencies) cannot be compiled to Javascript, for instance most of our HTTP implementation. In`
			theses cases we provide a replacement class. These classes start with `T` (for instance `THttpRequest`), which are
			`specially handled in the next step.`

			- `src/builder`: This module consumes the above code and compiles everything to Javascript using TeaVM. There's a
			`couple of places where we need to patch the bytecode before compiling it, so this also includes a basic ASM`
			`rewriting system.`

			- `src/frontend`: This consumes the interface exposed by the main emulator, and actually embeds the emulator in the
			`website.`

			`## Static content`
			`Rendering the static portion of the website is fortunately much simpler.`

			`- Doc generation: This is mostly handled in various Gradle files. The Forge Gradle script uses [cct-javadoc] to convert`
			`Javadoc on our peripherals and APIs to LDoc/[illuaminate] compatible documentation. This is then fed into illuaminate`
			`which spits out HTML.`

			- `src/htmlTransform`: We do a small amount of post-processing on the HTML in order. This project does syntax
			highlighting of non-Lua code blocks, and replaces special `<mc-recipe>` tags with a rendered view of a given
			`Minecraft recipe.`

			`[TeaVM]: https://github.com/konsoletyper/teavm "TeaVM - Compiler of Java bytecode to JavaScript"`
			`[cct-javadoc]: https://github.com/cc-tweaked/cct-javadoc: "cct-javadoc - A Javadoc doclet to extract documentation from @LuaFunction methods."`
			`[illuaminate]: https://github.com/Squiddev/illuaminate: "illuaminate - Very WIP static analysis for Lua"`