24 lines
544 B
TypeScript
24 lines
544 B
TypeScript
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export default class Selector<T> {
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private last: T
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private index: number[]
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constructor(private list: T[], private same: boolean, weight: (el: T) => number) {
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this.index = list.map((s, idx) => Array(weight(s)).fill(idx)).reduce((a, b) => a.concat(b))
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}
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next() {
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if (this.same) {
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if (this.last === undefined) {
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this.last = this.select()
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}
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return this.last
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}
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return this.select()
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}
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private select() {
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return this.list[this.index[Math.floor(Math.random() * this.index.length)]]
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}
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}
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