from tkinter import *
from datetime import date
import all_constants as c
import converter as cr
from display_help import DisplayHelp
from history_export_v2 import HistoryExport


class Converter:
    # Currency conversion tool (NZD to other currencies)

    def __init__(self):
        # Currency converter GUI
        self.all_calculations_list = []

        self.curr_frame = Frame(padx=10, pady=10)
        self.curr_frame.grid()

        self.curr_heading = Label(self.curr_frame,
                                  text="Currency Converter",
                                  font=("Arial", "16", "bold"))
        self.curr_heading.grid(row=0)

        instructions = ("Please enter an amount in NZD below and "
                        "then press one of the buttons to convert it.")
        self.curr_instructions = Label(self.curr_frame,
                                       text=instructions,
                                       wraplength=250,
                                       width=40,
                                       justify="left")
        self.curr_instructions.grid(row=1)

        self.curr_entry = Entry(self.curr_frame, font=("Arial", "14"))
        self.curr_entry.grid(row=2, padx=10, pady=10)

        self.answer_error = Label(self.curr_frame,
                                  text="Enter an amount to convert",
                                  fg="#004C99",
                                  font=("Arial", "14", "bold"))
        self.answer_error.grid(row=3)

        self.button_frame = Frame(self.curr_frame)
        self.button_frame.grid(row=4)

        button_details_list = [
            ["To USD", "#990099", lambda: self.check_amount("USD"), 0, 0],
            ["To EUR", "#009900", lambda: self.check_amount("EUR"), 0, 1],
            ["To GBP", "#CC0000", lambda: self.check_amount("GBP"), 1, 0],
            ["To JPY", "#CC6600", lambda: self.check_amount("JPY"), 1, 1],
            ["To AUD", "#006666", lambda: self.check_amount("AUD"), 2, 0],
            ["Help / Info", "#666666", self.to_help, 2, 1],
            ["History / Export", "#004C99", self.to_history, 3, 0],
        ]

        self.button_ref_list = []
        for item in button_details_list:
            make_button = Button(self.button_frame,
                                 text=item[0],
                                 bg=item[1],
                                 fg="#FFFFFF",
                                 font=("Arial", "12", "bold"),
                                 width=12,
                                 command=item[2])
            make_button.grid(row=item[3], column=item[4], padx=5, pady=5)
            self.button_ref_list.append(make_button)

        # history button is index 6 in the list
        self.to_history_button = self.button_ref_list[6]
        self.to_history_button.config(state=DISABLED)

    def check_amount(self, to_currency):
        # checks the amount is valid and converts or shows error
        to_convert = self.curr_entry.get()

        self.answer_error.config(fg="#004C99", font=("Arial", "13", "bold"))
        self.curr_entry.config(bg="#FFFFFF")

        error = "Please enter a positive number"
        has_errors = "no"

        try:
            to_convert = float(to_convert)
            if to_convert > 0:
                self.convert(to_currency, to_convert)
            else:
                has_errors = "yes"
        except ValueError:
            has_errors = "yes"

        if has_errors == "yes":
            self.answer_error.config(text=error, fg="#9C0000",
                                     font=("Arial", "13", "bold"))
            self.curr_entry.config(bg="#F4CCCC")
            self.curr_entry.delete(0, END)

    def convert(self, to_currency, to_convert):
        # converts NZD to chosen currency and saves to history
        if to_currency == "USD":
            answer = cr.to_usd(to_convert)
            answer_statement = f"NZ${to_convert:.2f} = US${answer}"
        elif to_currency == "EUR":
            answer = cr.to_eur(to_convert)
            answer_statement = f"NZ${to_convert:.2f} = €{answer}"
        elif to_currency == "GBP":
            answer = cr.to_gbp(to_convert)
            answer_statement = f"NZ${to_convert:.2f} = £{answer}"
        elif to_currency == "JPY":
            answer = cr.to_jpy(to_convert)
            answer_statement = f"NZ${to_convert:.2f} = ¥{answer}"
        else:   
            answer = cr.to_aud(to_convert)
            answer_statement = f"NZ${to_convert:.2f} = AU${answer}"

        self.to_history_button.config(state=NORMAL)
        self.answer_error.config(text=answer_statement)
        self.all_calculations_list.append(answer_statement)

    def to_help(self):
        # opens help window
        DisplayHelp(self)

    def to_history(self):
        # opens history window
        HistoryExport(self, self.all_calculations_list)


# main routine
if __name__ == "__main__":
    root = Tk()
    root.title("Currency Converter")
    Converter()
    root.mainloop()