Strategy_pattern

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class Navigator {
  public routeForCar(A,B) {
    ... calulate optimal route when user use car
  }
}

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class Navigator {
  public routeForCar(A,B) {
    ... calulate optimal route when user use car
  }
  public routeForWalker(A,B) {
    ... calulate optimal route when user use walking
  }
  public routeForPublicTransport(A,B) {
    ... calulate optimal route when user use transport
  }
  ...
}

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class Navigator {
  public calculateOptimalRoute(A,B){

  }
}

class Walker extends Navigator{}

class Car extends Navigator {}

class PublicTransport extends Navigator {}

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class Navigation {
  private strategy: Strategy;

  constructor(strategy: Strategy) {
    this.strategy = strategy;
  }

  public setStrategy(strategy: Strategy) {
    this.strategy = strategy;
  }

  public doSomethingBussinessLogic(): void {
    // input start point and end point
    this.strategy.setStartAndEndPoint("a", "b");
    const result = this.strategy.doAlgorithm(["a", "b", "c", "d", "e"]);
    console.log(result.join(","));
  }
}

interface Strategy {
  setStartAndEndPoint(start: string, end: string);
  doAlgorithm(data: string[]): string[];
}

class User implements Strategy {
  private startPoint: string;
  private endPoint: string;
  doAlgorithm(data: string[]): string[] {
    return data;
  }
  setStartAndEndPoint(start: string, end: string) {
    this.startPoint = start;
    this.endPoint = end;
  }
}

class Walker extends User {
  doAlgorithm(data: string[]): string[] {
    return data.sort();
  }
}

class Car extends User {
  doAlgorithm(data: string[]): string[] {
    return data.sort();
  }
}

class PublicTransport extends User {
  doAlgorithm(data: string[]): string[] {
    return data.reverse();
  }
}

const navigation = new Navigation(new Walker());
navigation.doSomethingBussinessLogic();