import React, { useContext, useState, useEffect, useRef } from "react";
import api from "../../services/fleetsAPI";
import updatesApi from "../../services/updatesAPI";
import vehiclesAPI from "../../services/vehiclesAPI";
import { downloadPercent, installPercent } from "./CarUpdatesContext";
import { validateCANID, validateFilter, validateVIN } from "../../utils/validationSupplier";
import Polling from "../../utils/polling";

const FleetContext = React.createContext();

export const FleetProvider = ({ children }) => {
  const [busy, setBusy] = useState(false);

  const [fleet, setFleet] = useState({});

  const [fleets, setFleets] = useState([]);
  const [totalFleets, setTotalFleets] = useState(0);

  const [fleetVehicles, setFleetVehicles] = useState([]);
  const [totalFleetVehicles, setTotalFleetVehicles] = useState(0);

  const [carUpdateIds, setCarUpdateIds] = useState([]);
  const carUpdateIdsRef = useRef();
  carUpdateIdsRef.current = carUpdateIds;

  const [fleetCANFilters, setFleetCANFilters] = useState([]);
  const [totalFleetCANFilters, setTotalFleetCANFilters] = useState(0);

  const addFleet = async (f, token) => {
    try {
      setBusy(true);
      validateFleet(f);

      const result = await api.addFleet(f, token);
      if (result.error) throw new Error(`Add fleet error. ${result.message}`);
      return result;
    } finally {
      setBusy(false);
    }
  };

  const getFleet = async (name, token) => {
    try {
      setBusy(true);
      validateFleetName(name);

      const result = await api.getFleet(name, token);
      if (result.error) {
        setFleet({});
        throw new Error(`Get fleet error. ${result.message}`);
      }

      setFleet(result);
      return result;
    } finally {
      setBusy(false);
    }
  };

  const getFleets = async (search, token) => {
    try {
      setBusy(true);

      const result = await api.getFleets(search, token);
      if (result.error) {
        setFleets([])
        throw new Error(`Get fleets error. ${result.message}`);
      }
      setFleets(result.data)
      if (result.total) {
        setTotalFleets(result.total);
      }
      return result;
    } finally {
      setBusy(false);
    }
  };

  const updateFleet = async (name, f, token) => {
    try {
      setBusy(true);

      validateFleetName(name);
      validateFleet(f);

      const result = await api.updateFleet(name, f, token);
      if (result.error) {
        throw new Error(`Update fleet error. ${result.message}`);
      }
      return result;
    } finally {
      setBusy(false);
    }
  };

  const deleteFleet = async (name, token) => {
    try {
      setBusy(true);

      validateFleetName(name);

      const result = await api.deleteFleet(name, token);
      if (result.error) {
        throw new Error(`Delete filter error. ${result.message}`);
      }

      return result;
    } finally {
      setBusy(false);
    }
  };

  const getFleetVehicles = async (name, search, token) => {
    try {
      setBusy(true);

      const result = await api.getFleetVehicles(name, search, token);
      if (result.error) {
        setFleetVehicles([])
        throw new Error(`Get fleet vehicles error. ${result.message}`);
      }

      const vins = result.data.map(vehicle => vehicle.vin);
      const connectionsResult = await vehiclesAPI.getConnections({ "VINs": vins }, token)
      if (connectionsResult.error) {
        setFleetVehicles([])
        throw new Error(`Get vehicles connections error. ${result.message}`);
      }

      var cars = []
      result.data.forEach((vehicle) => {
        cars.push({
          vin: vehicle.vin,
          connected: connectionsResult[vehicle.vin] || false,
          connectedHMI: connectionsResult[`2:${vehicle.vin}`] || false,
          trex_version: vehicle.carstate?.trex_version || "",
          car_update_id: vehicle.carupdate?.id || "",
          car_update_name: vehicle.carupdate?.updatemanifest?.name || "",
          car_update_status: vehicle.carupdate?.status || "",
          car_update_type: vehicle.carupdate?.updatemanifest?.type || "",
          voltage: vehicle.carstate?.battery?.battery_voltage,
          charge: vehicle.carstate?.battery?.percent,
          charge_type: vehicle.carstate?.vcu0x260?.charge_type,
          park: vehicle.carstate?.gear?.in_park,
        });
      });

      setFleetVehicles(cars)
      if (result.total) {
        setTotalFleetVehicles(result.total);
      }
      return result;
    } finally {
      setBusy(false);
    }
  };

  const watchFleetVehicles = new Polling(async ({ token }) => {
    const result = await updatesApi.getCarUpdateProgress(
      carUpdateIdsRef.current.join(","),
      token
    )
      .then((result) => {
        if (!Array.isArray(result?.statuses)) {
          return Promise.reject();
        }
        return result;
      })
      .catch(() => {
        return Promise.reject();
      });

    let pivot = result.statuses?.length ? result.statuses.length - 1 : 0;

    setFleetVehicles((fleetVehicles) => fleetVehicles.map((vehicle) => {
      result.statuses.find((status, i) => {
        if (vehicle.car_update_id !== status.car_update_id) {
          return false;
        }

        switch (status.msg) {
          case "downloading":
            vehicle.car_update_progress = downloadPercent(status);
            vehicle.car_update_status = `${status.ecu} downloading ${vehicle.car_update_progress}%`.trim();
            break;
          case "package_download_complete":
            vehicle.car_update_progress = 100;
            vehicle.car_update_status = `download complete`;
            break;
          case "installing":
            vehicle.car_update_progress = installPercent(status);
            vehicle.car_update_status = `${status.ecu} installing ${vehicle.car_update_progress}%`.trim();
            break;
          case "package_install_complete":
            vehicle.car_update_progress = 100;
            vehicle.car_update_status = `install complete`;
            break;
          default:
            vehicle.car_update_progress = -1;
            vehicle.car_update_status = status.msg;
            break;
        }

        // Move found status' to end to reduce time complexity to Ologn
        result.statuses[i] = result.statuses[pivot];
        result.statuses[pivot] = status;
        pivot -= 1;

        return true;
      });
      return vehicle;
    }));
    return Promise.resolve();
  }, 2000);

  const addFleetVehicles = async (name, vehicles, token) => {
    try {
      setBusy(true);

      validateFleetName(name);

      for (const vin of vehicles.vins) {
        validateVIN(vin);
      }

      const result = await api.addFleetVehicles(name, vehicles, token);
      if (result.error) {
        throw new Error(`Add fleet vehicle error. ${result.message}`);
      }
      return result;
    } finally {
      setBusy(false);
    }
  };

  const deleteFleetVehicle = async (name, vehicle, token) => {
    try {
      setBusy(true);

      validateFleetName(name);
      validateVIN(vehicle.vin);

      const result = await api.deleteFleetVehicle(name, vehicle, token);
      if (result.error) {
        throw new Error(`Delete fleet vehicle error. ${result.message}`);
      }

      const index = fleetVehicles.findIndex(element => element === vehicle.vin);
      if (index >= 0) fleetVehicles.splice(index, 1);
      return result;
    } finally {
      setBusy(false);
    }
  };

  const getFleetCANFilters = async (name, search, token) => {
    try {
      setBusy(true);

      const result = await api.getFleetCANFilters(name, search, token);
      if (result.error) {
        setFleetCANFilters([])
        throw new Error(`Get fleet filters error. ${result.message}`);
      }

      setFleetCANFilters(result.data)
      if (result.total) {
        setTotalFleetCANFilters(result.total);
      }
      return result;
    } finally {
      setBusy(false);
    }
  };

  const addFleetCANFilter = async (name, filter, token) => {
    try {
      setBusy(true);

      validateFleetName(name);
      validateFilter(filter);

      const result = await api.addFleetCANFilter(name, filter, token);
      if (result.error) {
        throw new Error(`Add fleet CAN filter error. ${result.message}`);
      }
      return result;
    } finally {
      setBusy(false);
    }
  }

  const updateFleetCANFilter = async (name, can_id, filter, token) => {
    try {
      setBusy(true);

      validateFleetName(name);
      validateFilter(filter);

      const result = await api.updateFleetCANFilter(name, can_id, filter, token);
      if (result.error) {
        throw new Error(`Update fleet CAN filter error. ${result.message}`);
      }
      return result;
    } finally {
      setBusy(false);
    }
  }

  const deleteFleetCANFilter = async (name, can_id, token) => {
    try {
      setBusy(true);

      validateFleetName(name);
      validateCANID(can_id);

      const result = await api.deleteFleetCANFilter(name, can_id, token);
      if (result.error) {
        throw new Error(`Delete fleet vehicle error. ${result.message}`);
      }

      const index = fleetCANFilters.findIndex(element => element.can_id === can_id);
      if (index >= 0) fleetCANFilters.splice(index, 1);
      return result;
    } finally {
      setBusy(false);
    }
  };

  useEffect(() => {
    setCarUpdateIds(() => fleetVehicles
      .filter((vehicle) => vehicle.car_update_status && vehicle.car_update_status !== "installed")
      .map((vehicle) => vehicle.car_update_id));
  }, [fleetVehicles, setCarUpdateIds]);

  return (
    <FleetContext.Provider
      value={{
        busy,

        fleet,
        fleets,
        totalFleets,
        addFleet,
        getFleet,
        getFleets,
        updateFleet,
        deleteFleet,

        fleetVehicles,
        totalFleetVehicles,
        watchFleetVehicles,
        getFleetVehicles,
        addFleetVehicles,
        deleteFleetVehicle,

        fleetCANFilters,
        totalFleetCANFilters,
        getFleetCANFilters,
        addFleetCANFilter,
        updateFleetCANFilter,
        deleteFleetCANFilter
      }}
    >
      {children}
    </FleetContext.Provider>
  );
};

const validateFleet = (f) => {
  if (f == null) {
    throw new Error("No fleet data");
  }

  validateFleetName(f.name);
}

const validateFleetName = (name) => {
  if (name == null || !/^[\w-]+$/.test(name)) {
    throw new Error("Invalid name");
  }
};

export const useFleetContext = () => useContext(FleetContext);