package com.ufund.api.ufundapi.service;

import java.io.IOException;
import java.util.Arrays;

import org.springframework.context.annotation.Lazy;
import org.springframework.stereotype.Component;

import com.ufund.api.ufundapi.DuplicateKeyException;
import com.ufund.api.ufundapi.model.Need;
import com.ufund.api.ufundapi.persistence.CupboardDAO;

@Component
public class CupboardService {

    private final CupboardDAO cupboardDAO;
    final AuthService authService;

    public CupboardService(@Lazy AuthService authService, CupboardDAO cupboardDAO) {
        this.authService = authService;
        this.cupboardDAO = cupboardDAO;
    }

    /**
     * Creates a new Need
     *
     * @param name The name of the need to create
     * @param image The image representation of the need to create
     * @param location The location of the new need
     * @param maxGoal The max goal of the new need
     * @param goalType The goal type of the new need
     * @param urgent The urgency of the new need
     * @param description The description of the new need
     * @return The need that was created
     * @throws IOException Thrown if there was any issue saving the data
     * @throws DuplicateKeyException If there already exists a need with the same name
     */
    public Need createNeed(String name, String image, String location, double maxGoal, Need.GoalType goalType, boolean urgent, String description) throws IOException, DuplicateKeyException {

        if (maxGoal <= 0) {
            throw new IllegalArgumentException("Max Goal must be greater than zero");
        } else if (goalType.equals(Need.GoalType.PHYSICAL) && maxGoal % 1 != 0) {
            throw new IllegalArgumentException("Cannot have non whole number value for physical goal");
        } else if (name == null || name.isEmpty()) {
            throw new IllegalArgumentException("Required fields cannot be blank");
        }

        for (Need searchNeed : cupboardDAO.getNeeds()) {
            if (searchNeed.getName().equalsIgnoreCase(name)) {
                throw new DuplicateKeyException("Duplicate names are not allowed");
            }
        }

        Need need = new Need(name, image, location, maxGoal, goalType, urgent, description);
        return cupboardDAO.addNeed(need);

    }

    /**
     * Get all the needs in the cupboard
     *
     * @return An array containing all needs
     * @throws IOException Thrown if there was any issue saving the data
     */
    public Need[] getNeeds() throws IOException {
        return cupboardDAO.getNeeds();
    }

    /**
     * Returns an array of needs filtered by a search
     *
     * @param search The search substring
     * @return The requested array
     * @throws IOException Thrown if there was any issue saving the data
     */
    public Need[] searchNeeds(String search) throws IOException {
        return Arrays.stream(cupboardDAO.getNeeds())
                .filter(i -> i.getName().toLowerCase().contains(search.toLowerCase()))
                .toArray(Need[]::new);
    }

    /**
     * Gets a need with the specified ID
     *
     * @param id the ID of the need
     * @return The resulting Need or null if the need was not found
     */
    public Need getNeed(int id) throws IOException {
        return cupboardDAO.getNeed(id);
    }

    /**
     * Updates a need
     *
     * @param id The ID of the need to update
     * @param need The need object to set (note: the ID is ignored)
     * @return The updated need object
     * @throws IOException Thrown if there was an issue saving the changes
     */
    public Need updateNeed(Need need, int id) throws IOException {
        if (need.getId() != id) {
            throw new IllegalArgumentException("ID in URL and body must match");
        }
        if (need.getMaxGoal() <= 0) {
            throw new IllegalArgumentException("Goal must be greater than 0");
        } else if (need.getType().equals(Need.GoalType.PHYSICAL) && need.getMaxGoal() % 1 != 0) {
            throw new IllegalArgumentException("Cannot have non whole number value for physical goal");
        } else if (need.getName() == null || need.getName().isEmpty()) {
            throw new IllegalArgumentException("Required fields cannot be blank");
        }
        return cupboardDAO.updateNeed(need);
    }

    /**
     * Checks out a need with the desired amount
     * 
     * @param id The ID of the need to update
     * @param checkoutAmount The amount to update the need by
     * @throws IOException If there is an error reading the file
     * @throws IllegalAccessException If the user has insufficient permission
    */
    public void checkoutNeed(int id, double checkoutAmount, String key) throws IOException, IllegalAccessException {
        if (checkoutAmount <= 0) {
            throw new IllegalArgumentException("Amount must be greater than 0");
        }
        if ((checkoutAmount % 1 != 0) && (cupboardDAO.getNeed(id).getType() == Need.GoalType.PHYSICAL)) {
            throw new IllegalArgumentException("Physical amounts must be whole numbers");
        }
        authService.keyIsValid(key);
        Need need = cupboardDAO.getNeed(id);
        need.incrementCurrent(checkoutAmount);
    }

    /**
     * Delete a need from the cupboard
     *
     * @param id the ID of the need
     * @return True if the need was deleted
     * @throws IOException Thrown on any problem removing the need
     */
    public boolean deleteNeed(int id) throws IOException {
        
        return cupboardDAO.deleteNeed(id);
    }
}