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interface NavigationMap {
  launch(latLng: LatLng): Promise<void>
  // 他の地図制御メソッド 省略
  dispose(): void
}
  
interface MarkerIndicationMap {
  launch(latLng: LatLng): Promise<void>
  // 省略
  dispose(): void
}

import AppleNavigationMap from "./navigation-map"
import AppleMarkerIndicationMap from "./marker-indication-map"

export const getNavigationMap: (element: HTMLElement) => NavigationMap = 
  (element: HTMLElement) => new AppleNavigationMap(element)

export const getMarkerIndicationMap: (element: HTMLElement) => MarkerIndicationMap =
  (element: HTMLElement) => new AppleMarkerIndicationMap(element)

type Mapkit = any

export default abstract class AppleMaps {

  private static mapKit: Mapkit

  protected static async getMapKit(): Promise<Mapkit> {

    if (this.mapKit) {
      return this.mapKit
    }

    await new Promise(resolve => {
      const element = document.createElement("script")
      element.addEventListener("load", resolve, { once : true })
      element.src = "https://cdn.apple-mapkit.com/mk/5.x.x/mapkit.js"
      element.crossOrigin = "anonymous"
      document.head.appendChild(element)
    })

    this.mapKit = await new Promise((resolve, reject) => {
      const mapKit = (globalThis as any).mapkit

      mapKit.init({
        // libraries: ["services", "full-map", "annotations"],
        authorizationCallback: function(done: any) {
          done("-- TOKEN --")
        },
        language: "ja"
      })

      mapKit.addEventListener("configuration-change", (event: any) => {
        switch (event.status) {
          case "Initialized":
            resolve(mapKit)
            return
          // case "Refreshed":
          // default:
        }
        reject(event)
      })

      mapKit.addEventListener("error", (error: any) => reject(error))
    })

    return this.mapKit
  }
}

import AppleMaps from "./apple-maps"

export default class AppleNavigationMap extends AppleMaps implements NavigationMap {

  private element: HTMLElement
  private map: any = undefined

  constructor(element: HTMLElement) {
    super()
    this.element = element
  }

  private async getMap() {
    if (this.map) {
      return this.map
    }
    const mapKit = await AppleMaps.getMapKit()
    this.map = new mapKit.Map(this.element, {
      // 省略
    })
    return this.map
  }

  async launch(latLng: LatLng) {
    const mapKit = await AppleMaps.getMapKit()
    const map = await this.getMap()
    map.region = new mapKit.CoordinateRegion(
      // 省略
    )
  }

  // 他の地図制御メソッド 省略

  dispose() {
    this.map?.destroy()
  }
}

abstract class AppleMaps {

  private static MapKit mapKit;

  static synchronized MapKit getMapKit() {
    if (mapKit != null) {
      return mapKit;
    }
    // MapKit 生成処理
  }
}

abstract class AppleMaps {

  protected companion object {
    val mapKit by lazy {
      // MapKit 生成処理
    }
  }
}

class Mutex {
  private mutex = Promise.resolve();

  async lock<T>(fn: () => Promise<T>): Promise<T> {
    let release: () => void;
    const releasePromise = new Promise<void>(resolve => release = resolve);

    // finally の代わりに then と catch を使ってロックを解放
    const result = this.mutex.then(() => fn())
      .then(
        (value) => {
          release(); // 正常終了時にリリース
          return value;
        },
        (error) => {
          release(); // エラー時にも必ずリリース
          throw error;
        }
      );

    this.mutex = releasePromise;

    return result;
  }
}

const mutex = new Mutex();

async function criticalSection(id: number) {
  console.log(`Task ${id} is waiting to enter the critical section.`);
  await mutex.lock(async () => {
    console.log(`Task ${id} has entered the critical section.`);
    // クリティカルセクションに入った後、非同期の処理をシミュレート
    await new Promise(resolve => setTimeout(resolve, 1000)); 
    console.log(`Task ${id} is leaving the critical section.`);
  });
}

async function runTasks() {
  await Promise.all([
    criticalSection(1),
    criticalSection(2),
    criticalSection(3)
  ]);
}

runTasks();

type Mapkit = any

export default abstract class AppleMaps {

  private static mapKit: Mapkit
  private static mutex = new Mutex()

  protected static async getMapKit(): Promise<Mapkit> {
 
    await this.mutex.lock(async () => {

      if (this.mapKit) {
        return
      }
      
      await new Promise(resolve => {
        const element = document.createElement("script")
        element.addEventListener("load", resolve, { once : true })
        element.src = "https://cdn.apple-mapkit.com/mk/5.x.x/mapkit.js"
        element.crossOrigin = "anonymous"
        document.head.appendChild(element)
      })
  
      this.mapKit = await new Promise((resolve, reject) => {
        const mapKit = (globalThis as any).mapkit;
        (globalThis as any).mapkit = undefined
        
        mapKit.init({
          // libraries: ["services", "full-map", "annotations"],
          authorizationCallback: function(done: any) {
            done("-- TOKEN --")
          },
          language: "ja"
        })
        
        mapKit.addEventListener("configuration-change", (event: any) => {
          switch (event.status) {
            case "Initialized":
              resolve(mapKit)
              return
            // case "Refreshed":
            // default:
          }
          reject(event)
        })
        
        mapKit.addEventListener("error", (error: any) => reject(error))
      })
    })
    
    return this.mapKit
  }
}