const path = require("path");
const fs = require("fs");
const { sources } = require("webpack");

const { getFileNameHash } = webpackRequire("utils/filename-hash");

class CreateInjectedSharedModulesPlugin {
	constructor({ injectedSharedModulesImportedCount, sortedSharedModules }) {
		this.injectedSharedModulesImportedCount = injectedSharedModulesImportedCount;
		this.sortedSharedModules = sortedSharedModules;
	}

	apply(compiler) {
		compiler.hooks.compilation.tap("CreateInjectedSharedModulesPlugin", compilation => {
			compilation.hooks.processAssets.tap(
				{
					name: "CreateInjectedSharedModulesPlugin",
					stage: compiler.webpack.Compilation.PROCESS_ASSETS_STAGE_ADDITIONAL
				},
				assets => {
					const injectedSharedScripts = this.sortedSharedModules
						.filter(sharedModule => this.injectedSharedModulesImportedCount[sharedModule] > 0)
						.map(sharedModule => `shared/${getFileNameHash(sharedModule, "shared")}.js`);

					if (injectedSharedScripts.length > 0) {
						const scriptInjectorModuleName = getFileNameHash("script-injector", "shared", true);
						const injectionCode = injectedSharedScripts
							.map(injectedScript => `$${scriptInjectorModuleName}.injectScriptHead("shared/${path.basename(injectedScript)}");`)
							.join("");
						compilation.emitAsset(
							`shared/${getFileNameHash("injected-shared-modules", "shared")}.js`,
							new sources.RawSource(injectionCode)
						);
					}
				}
			);
		});
	}
}

module.exports = CreateInjectedSharedModulesPlugin;