P04.Agents

package agents;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.*;

public class Main {
    public static void main(String[] args) throws IOException {
        Map<String, Map<String, Double>> agentMissions = new LinkedHashMap<>();
        Map<String, Double> missions = new HashMap<>();

        BufferedReader consoleReader = new BufferedReader(new InputStreamReader(System.in));

        String input;
        while (!("registration".equals(input = consoleReader.readLine()))) {
            if (isMission(input)) {
                String missionName = input.split(":")[0];
                Double missionRating = Double.parseDouble(input.split(":")[1]);
                missions.put(missionName, missionRating);
            } else if (isAgent(input)) {
                if (input.length() < 3)
                    continue;

                agentMissions.put(input, new LinkedHashMap<>());
            }
        }

        while (!("operate".equals(input = consoleReader.readLine()))) {
            String[] tokens= input.split("->");
            String operationName = tokens[0];

            switch (operationName) {
                case "assign":
                    assign(agentMissions, missions, tokens);
                    break;

                case "abort":
                    abort(agentMissions, tokens);
                    break;

                case "change":
                    change(agentMissions, tokens);
                    break;
            }
        }

        consoleReader.close();

        agentMissions.entrySet().stream() //streaming all agents
                .filter(a -> !a.getValue().isEmpty()) //remove all agents with 0 missions
                .sorted((a1, a2) -> Double.compare(sumRatings(a2.getValue()), sumRatings(a1.getValue()))) //descending
                .forEach(a -> {
                    System.out.printf("Agent: %s - Total Rating: %.2f%n", a.getKey(), sumRatings(a.getValue()));
                    a.getValue().entrySet().stream() //streaming a single agents missions
                            .sorted((m1, m2) -> Double.compare(m2.getValue(), m1.getValue())) //descending
                            .forEach(m -> {
                                System.out.printf(" - %s -> %.2f%n", m.getKey(), m.getValue());
                            });
                });
    }

    private static boolean isMission(String input) {
        return '#' == input.charAt(0);

    }

    private static boolean isAgent(String input) {
        return input.substring(input.length() - 3).charAt(0) == '0';
    }

    /*
    If command is "assign" – line format will be:  assign->{agentName}->{missionName}.
    Your task is to assign a mission with its rating to a given agent.
    (One agent cannot assign a mission twice, but one mission can be assigned to many agents.)
    ONLY REGISTERED MISSION CAN BE ASSIGNED.
     */
    private static void assign(Map<String, Map<String, Double>> agentMissions, Map<String, Double> missions, String... tokens) {
        String agentName = tokens[1];
        String missionName = tokens[2];

        if (!missions.containsKey(missionName))
            return;

        if (!agentMissions.containsKey(agentName))
            return;

        agentMissions.get(agentName).put(missionName, missions.get(missionName));
    }

    /*
    If command is "abort" – line format will be: abort->{missionName}.
    Remove a mission from every agent that is assigned to it (one or many).
     */
    private static void abort(Map<String, Map<String, Double>> agentMissions, String... tokens) {
        String missionName = tokens[1];

        for (Map<String, Double> missionNameRating : agentMissions.values()) {
            missionNameRating.remove(missionName);
        }
    }

    /*
    If command is "change" – line format will be: change->{agentName}->{agentName}.
    Swap the missions with their ratings, of the two given agents (they are always be valid).
     */
    private static void change(Map<String, Map<String, Double>> agentMissions, String... tokens) {
        String firstAgentName = tokens[1];
        String secondAgentName = tokens[2];

        Map<String, Double> firstAgentsMissions = agentMissions.get(firstAgentName);
        Map<String, Double> secondAgentMissions = agentMissions.get(secondAgentName);

        agentMissions.put(firstAgentName, secondAgentMissions); //updates
        agentMissions.put(secondAgentName, firstAgentsMissions); //updates
    }

    private static Double sumRatings(Map<String, Double> missions) {
        return missions.entrySet().stream().mapToDouble(m -> m.getValue()).sum();
    }
}