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


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, switch: str):
        assert(switch == "time" or switch == "co2")

        print("Performing Dijkstra on the following graph...")
        for vertex in self.graph:
            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 switch == "time":
                    if time < self.table[key]["distance"][0]:
                        self.table[key]["distance"] = (time, co2)
                        self.table[key]["prev"] = v1
                elif switch == "co2":
                    if co2 < self.table[key]["distance"][1]:
                        self.table[key]["distance"] = (time, co2)
                        self.table[key]["prev"] = v1

        print("Final Dijkstra table:", self.table)

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

        total_time = 0
        total_co2 = 0

        while start not in sequence:
            current = self.table[sequence[-1]]  # last element of list
            prev = current["prev"]
            total_time += current["distance"][0]
            total_co2 += current["distance"][1]
            sequence.append(prev)

        sequence.reverse()
        print(sequence)
        print("Total Time:", total_time)
        print("Total CO2:", total_co2)