maps-helper-functions.js

const directionsAPI = process.env.EXPO_PUBLIC_GOOGLE_API_KEY;


export const generateMarkersFromData = ({ data, userLatitude, userLongitude }) => {

  return data.map((driver, index) => {

    const latOffset = (index % 5) * 0.002;

    const lngOffset = ((index + 1) % 5) * 0.002;


    return {
      latitude: userLatitude + latOffset,
      longitude: userLongitude + lngOffset,
      title: `${driver.first_name} ${driver.last_name}`,
      ...driver,
    };

  });
  
};



export const calculateRegion = ({ userLatitude, userLongitude, destinationLatitude, destinationLongitude }) => {


  if (!userLatitude || !userLongitude) {

    return {
      latitude: 37.78825,
      longitude: -122.4324,
      latitudeDelta: 0.01,
      longitudeDelta: 0.01,
    };

  }


  if (!destinationLatitude || !destinationLongitude) {

    return {
      latitude: userLatitude,
      longitude: userLongitude,
      latitudeDelta: 0.01,
      longitudeDelta: 0.01,
    };

  }


  const minLat = Math.min(userLatitude, destinationLatitude);

  const maxLat = Math.max(userLatitude, destinationLatitude);

  const minLng = Math.min(userLongitude, destinationLongitude);

  const maxLng = Math.max(userLongitude, destinationLongitude);


  const latitudeDelta = (maxLat - minLat) * 1.3; 

  const longitudeDelta = (maxLng - minLng) * 1.3; 


  const latitude = (userLatitude + destinationLatitude) / 2;

  const longitude = (userLongitude + destinationLongitude) / 2;


  return {
    latitude,
    longitude,
    latitudeDelta,
    longitudeDelta,
  };


};


export const calculateDriverTimes = async ({ markers, userLatitude, userLongitude, destinationLatitude, destinationLongitude }) => {

  if ( !userLatitude || !userLongitude || !destinationLatitude || !destinationLongitude ) {

    return;

  }
    

  try {

    const timesPromises = markers.map(async (marker) => {

      const responseToUser = await fetch(
        `https://maps.googleapis.com/maps/api/directions/json?origin=${marker.latitude},${marker.longitude}&destination=${userLatitude},${userLongitude}&key=${directionsAPI}`
      );

      const dataToUser = await responseToUser.json();

      const timeToUser = dataToUser.routes[0].legs[0].duration.value; 


      const responseToDestination = await fetch(
        `https://maps.googleapis.com/maps/api/directions/json?origin=${userLatitude},${userLongitude}&destination=${destinationLatitude},${destinationLongitude}&key=${directionsAPI}`
      );


      const dataToDestination = await responseToDestination.json();

      const timeToDestination = dataToDestination.routes[0].legs[0].duration.value; 


      const totalTime = (timeToUser + timeToDestination) / 60; 

      const price = (totalTime * 0.5).toFixed(2); 

      return { ...marker, time: totalTime, price };

    });


    return await Promise.all(timesPromises);

  } catch (error) {

    console.error('Error calculating driver times:', error);

  }

};