"""
This module holds the logic for the solving
"""

from args import Settings
from parser import DataSet


class Dijkstra():
    def __init__(self, graph: dict, connection: tuple):
        """
        table: matrix with vertex as key, price and prev vertex as value
        OL: open list, to keep track of finished vertecis
        """
        self.graph = graph
        self.table = {}
        for vertex in graph:
            self.table.update({vertex: {
                                 "distance": (9999999, 999999),
                                 "prev": None}})
        self.table[connection[0]]["distance"] = (0, 0)

    def algorithm(self, settings: Settings):
        if settings.debug:
            print("Performing Dijkstra on the following graph...")
        for vertex in self.graph:
            if settings.debug:
                print(f"{vertex}: {self.graph[vertex]}")
                print("")

        for v1 in self.graph.keys():
            neighbors = self.graph[v1]
            for n in neighbors:
                key = [elem for elem in n.keys()][0]  # name of neighbor node
                edge = (n[key]["time"], n[key]["co2"])

                # update both time and co2
                time = self.table[v1]["distance"][0] + edge[0]
                co2 = self.table[v1]["distance"][1] + edge[1]
                # but only eval the one we want
                if settings.sort == "time":
                    if time < self.table[key]["distance"][0]:
                        self.table[key]["distance"] = (time, co2)
                        self.table[key]["prev"] = v1
                elif settings.sort == "co2":
                    if co2 < self.table[key]["distance"][1]:
                        self.table[key]["distance"] = (time, co2)
                        self.table[key]["prev"] = v1

        if settings.debug:
            print("Final Dijkstra table:", self.table)

    def print_result(self, connection: tuple, dataset: DataSet):
        sequence = []
        (start, dest) = connection
        # start at destination
        sequence.append(dest)

        # go through all possibilities until we're back at start
        while start not in sequence:
            current = self.table[sequence[-1]]  # last element of list
            prev = current["prev"]
            sequence.append(prev)
        sequence.reverse()

        connection = dataset.connection
        frm = dataset.locations[connection[0]]
        to = dataset.locations[connection[1]]
        print(f"{frm.name}-->{to.name}")
        print("----")
        print(f"Lufstrecke: {frm.distance(to)}")
        total = ""
        for loc in sequence:
            total += f"{dataset.locations[loc].name}-->"
        # remove last arrow again
        total = total[0:-3]
        print(total)
        print("Total Time:", self.table[dest]["distance"][0])
        print("Total CO2:", self.table[dest]["distance"][1])