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import Site from "./site.ts";import { Page } from "./filesystem.ts";import { brightGreen, gray } from "./deps/colors.ts";
/** * Class to collect and return performance metrics */export default class Metrics {  site: Site;
  constructor(site: Site) {    this.site = site;  }
  /**   * Create a mark to start to measure   */  start(name: string, subject?: unknown, processor?: unknown) {    if (this.site.options.metrics) {      const markName = this.#getMarkName(name, subject, processor);      performance.mark(markName);    }  }
  /**   * Measure the time from a mark to now.   */  end(name: string, subject?: unknown, processor?: unknown) {    if (this.site.options.metrics) {      const markName = this.#getMarkName(name, subject, processor);      performance.measure(markName, markName);    }  }
  /**   * Generate an unique mark name   */  #getMarkName(name: string, subject?: unknown, processor?: unknown) {    if (processor) {      // @ts-ignore: processor is the type unknown      name += ` ${processor.name}`;    }    if (subject) {      name += `: ${        subject instanceof Page ? subject.src.path + subject.src.ext : subject      }`;    }    return name;  }
  /**   * Return the list of collected metrics   */  get entries() {    return performance.getEntriesByType("measure");  }
  /**   * Print the metrics in the console   */  print() {    // Sort by duration and get the 100 longest    const metrics = this.entries      .sort((a, b) => a.duration - b.duration)      .slice(-100);
    for (const metric of metrics) {      const duration = Math.round(metric.duration) + "ms";      const [name, file] = metric.name.split(": ");
      console.log(        `${brightGreen(duration.padStart(10))} ${name} ${gray(file || "")}`,      );    }  }
  /**   * Save the metrics data in a file   */  async save(file: string) {    await Deno.writeTextFile(file, JSON.stringify(this.entries));  }}