Example for: https://ogaston.com/en/blogs/factory-method-creational-design-pattern/

factory-method.ts

interface IAutomobile {
    tires: Tire[],
    engine: Engine
}

class Car implements IAutomobile { 
    constructor(public tires: Tire[], public engine: Engine) { } 
} 

class Tire { 
    constructor(public brand: string) { } 
} 
 
class Engine { 
    constructor(public cylinder: number) { } 
} 


class CarFactory { 

    joinTires(): Tire[] {  
        let tireSet = [] 

        for (let i = 0; i < 4; i++) { 
            tireSet.push(new Tire("Generic")) 
        } 

        return tireSet 
    }  

 

    createEngine(): Engine {  
        return new Engine(4) 
    } 


    buildCar(): IAutomobile {  
        const tires = this.joinTires() 
        const engine = this.createEngine() 
        return new Car(tires, engine); 
    } 

} 

class ElectricCar implements IAutomobile {
   constructor(public tires: Tire[], public engine: Engine) { } 
}

class ElectricEngine extends Engine {
    constructor(batteryAh: number ) {
        super(0)
    }
}

class ElectricCarFactory extends CarFactory {
    createEngine() {
        return new ElectricEngine(3.8)
    }

    buildCar() {
        const tires = this.joinTires() 
        const engine = this.createEngine() 
        return new ElectricCar(tires, engine); 
    }
}


const factory = new ElectricCarFactory() 

const car = factory.buildCar() 

console.log(car)