"""CLI: Show summarised information on a piggybank."""

from re import match
from sys import argv, exit, stderr

from piggybank import print_program_version, PIGGYBANK_FILE_EXTENSION
from piggybank.configuration import Configuration
from piggybank.cli import handle_default_arguments
from piggybank.currencies import CURRENCIES, \
    BaseCurrencyError
from piggybank.piggybank import PiggyBank

__all__ = ["main"]


USAGE_SHOW: str = "Usage: piggybank-show FILE [with t,transactions]\n\n" \
    "Show statistics about a piggybank.\n" \
    "FILE                 -- .pb file name of your piggybank;\n" \
    "with (t|transaction) -- also list all transactions.\n"

DEFAULT_COIN_CENTERING: int = 10


def parse_show_arguments(args):
    r = r"^(?P<file>\S+)(?= with (?P<transactions>t|transactions))?"
    argd = match(r, args)
    if not argd is None:
        argd = argd.groupdict()
        return {
            "file": argd["file"],
            "transactions": argd["transactions"] is None }


def print_summary(piggybank: PiggyBank,
                  centering: int = DEFAULT_COIN_CENTERING) -> None:
    """Print summarised information on a piggy bank.
    Prints a table with totals of how much coins of which face value are in a
    piggy bank; A total sum converted to its currency for each face value and
    overall total sum in a currency of a piggy bank."""
    def print_separator(left="┣", lmiddle="╋", rmiddle="╋", right="┫"):
        line = rmiddle.join('━' * centering
                            for _ in
                            range(CURRENCIES[piggybank.currency]['count']))
        print(f"{left}{'━'*27}{lmiddle}{line}{right}")

    cc, cs, ct = piggybank.count, piggybank.sum, piggybank.total

    cline = "┃".join([f'{l:^{centering}}'
                     for l in CURRENCIES[piggybank.currency]["names"]])
    cline_len = len(cline)

    print_separator(left="┏", lmiddle="┳", rmiddle="━", right="┓")
    print(f"┃{'currency':^27}┃"
          f"{CURRENCIES[piggybank.currency]['name']:^{cline_len}}┃")
    print_separator(rmiddle="┳")
    print(f"┃{'face values':^27}┃{cline}┃")
    print_separator()
    print(f"┃{'amount':^27}┃{'┃'.join([f'{c:^{centering}}' for c in cc])}┃")
    print_separator()
    print(f"┃{'sum':^27}┃"
          f"{'┃'.join(['{:^{}.2f}'.format(c / 100, centering) for c in cs])}┃")
    print_separator(rmiddle="┻")
    print(f"┃{'total':^27}┃{'{:^{}.2f}'.format(ct / 100, cline_len)}┃")
    print_separator(left="┗", lmiddle="┻", rmiddle="━", right="┛")


def print_transactions(piggybank, centering=DEFAULT_COIN_CENTERING):
    """Print a list of all transactions stored in a piggy bank."""
    def print_separator(left="┏", middle="┳", right="┓"):
        line = middle.join('━' * centering
                           for _ in
                           range(CURRENCIES[piggybank.currency]['count']))
        print(f"{left}━━━━━━━━━━━━━━━━━━━━━{middle}━━━━━{middle}{line}{right}")

    cline = "┃".join([f'{l:^{centering}}'
                     for l in CURRENCIES[piggybank.currency]["names"]])

    print_separator()
    print(f"┃{'Timestamp':^21}┃ I/O ┃{cline}┃")
    print_separator("┣", "╋", "┫")
    for tr in piggybank.transactions:
        coin_line = "┃".join([f'{c:^{centering}}' for c in tr.coins])
        ts = tr.timestamp.replace("T", " ")
        print(f"┃ {ts} ┃{tr.direction:^5}┃{coin_line}┃")
    print_separator("┗", "┻", "┛")


def main() -> None:
    handle_default_arguments(' '.join(argv), lambda: print(USAGE_SHOW))

    args = parse_show_arguments(' '.join(argv))

    try:
        piggybank = PiggyBank.from_file(args["file"])
        print_summary(piggybank)
        if args["transactions"]:
            print_transactions(piggybank)
    except BaseCurrencyError as err:
        print(f"{type(err).__name__}:", err, file=stderr)
    except FileNotFoundError as err:
        print(f"{type(err).__name__}:", f"{err} doesn't exist.", file=stderr)
    except Exception as err:
        print(f"Something went exceptionally wrong. Error:",
              f"{type(err).__name__}:", err, file=stderr)