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/*
*/
"use strict";
const RuntimeGlobals = require("../RuntimeGlobals");
const RuntimeModule = require("../RuntimeModule");
const Template = require("../Template");
/** @typedef {import("../Compilation")} Compilation */
/** @typedef {import("../Chunk").ChunkChildIdsByOrdersMap} ChunkChildIdsByOrdersMap */
class ChunkPreloadTriggerRuntimeModule extends RuntimeModule {
/**
* @param {ChunkChildIdsByOrdersMap} chunkMap map from chunk to chunks
* @param {string=} handlerKey the `ensureChunkHandlers` key to install under (default `"preload"`); `"cssPreload"` preloads only the CSS handler so it stays CSS-only even when the build also registers a JS preload handler
*/
constructor(chunkMap, handlerKey = "preload") {
super(`chunk ${handlerKey} trigger`, RuntimeModule.STAGE_TRIGGER);
/** @type {ChunkChildIdsByOrdersMap} */
this.chunkMap = chunkMap;
/** @type {string} */
this.handlerKey = handlerKey;
}
/**
* Generates runtime code for this runtime module.
* @returns {string | null} runtime code
*/
generate() {
const { chunkMap, handlerKey } = this;
const compilation = /** @type {Compilation} */ (this.compilation);
const { runtimeTemplate } = compilation;
// `cssPreload` calls only the CSS preload handler (`preloadChunkHandlers.s`)
// so it stays CSS-only regardless of a JS preload handler registered
// elsewhere; plain `preload` fans out to every handler via `preloadChunk`.
const body =
handlerKey === "cssPreload"
? [
`var handler = ${RuntimeGlobals.preloadChunkHandlers}.s;`,
"var chunks = chunkToChildrenMap[chunkId];",
"if (handler && Array.isArray(chunks)) chunks.forEach(handler);"
]
: [
"var chunks = chunkToChildrenMap[chunkId];",
`Array.isArray(chunks) && chunks.map(${RuntimeGlobals.preloadChunk});`
];
return Template.asString([
`var chunkToChildrenMap = ${JSON.stringify(chunkMap, null, "\t")};`,
`${
RuntimeGlobals.ensureChunkHandlers
}.${handlerKey} = ${runtimeTemplate.basicFunction("chunkId", body)};`
]);
}
}
module.exports = ChunkPreloadTriggerRuntimeModule;