#!/usr/bin/env python3

import argparse
import glob
import os
from cli import opt_generate_keypair
from cli import opt_save_private_key
from cli import opt_load_private_key
from cli import opt_save_public_key
from cli import opt_mine_block
from cli import opt_generate_transaction
from cli import opt_view_deck
from cli import msg_array
from cli import get_private_key_from_file
from cli import fetch_cards_json

DEFAULT_FILENAME: str = "privatekey";

def resolve_path(path: str | None) -> str | None:
    if not path or path.strip() == "":
        return None;
   
    path = path.strip();

    if not path.endswith(".pem"):
        path += ".pem";

    if os.path.exists(path) and os.path.isfile(path):
        return path;

    return None;


def resolve_path_for_key_creation(filename:str | None) -> str:
    default_name = "privatekey.pem";

    if not filename or filename.strip() == "":
        return default_name;

    filename = filename.strip();

    if os.path.isdir(filename):
        return os.path.join(filename, default_name);

    if not filename.endswith(".pem"):
        filename += ".pem";

    dir_path = os.path.dirname(filename);
    if dir_path and not os.path.exists(dir_path):
        os.makedirs(dir_path);

    return filename;

def get_first_pem_file():
    pem_files = glob.glob("*.pem");
    
    if pem_files:
        first_pem = min(pem_files, key=os.path.getmtime);
        return first_pem;
    else:
        return None;

def handle_createkey(args):
    rsa_key = opt_generate_keypair();
    filepath = resolve_path_for_key_creation(args.output);
    opt_save_private_key(rsa_key, filepath);
    print(msg_array[0]); 
    public_path = f"pub_{filepath}"
    opt_save_public_key(rsa_key, public_path);

def handle_mine(args):
    file = resolve_path(args.use);
    if not file:
        file = get_first_pem_file();
    if not file:
        msg_array[0] = "No valid private key found";
        return;

    opt_mine_block(file);


def handle_tx(args):

    file = resolve_path(args.use);
    if not file:
        file = get_first_pem_file();
    if not file:
        msg_array[0] = "No valid private key found";
        return;

    recv = resolve_path(args.receiver);
    if args.receiver and not recv:
        msg_array[0] = "No valid public key found (receiver)";
        return;

    opt_generate_transaction(file, recv);


def handle_deck(args):
    file = resolve_path(args.use);
    if not file:
        file = get_first_pem_file();
    if not file:
        msg_array[0] = "No valid private key found";
        return;

    rsa = get_private_key_from_file(file);
    if rsa is None:
        return;

    cards = fetch_cards_json(rsa);

    if len(cards) < 1:
        msg_array[0] = "You have no cards to view";
        return;

    for i, card in enumerate(cards):
        print(f"{i+1}. Card ID: {card['cardId']}, Page ID: {card['pageId']}");


def build_parser():
    parser = argparse.ArgumentParser(description="Wikideck CLI");
    subparsers = parser.add_subparsers(dest="command", required=True);

    #createkey
    p_create = subparsers.add_parser("createkey",aliases=["ck"], help="Create an RSA keypair and save it to the current directory");
    p_create.add_argument("-O", "--output", help="Optional custom filename (.pem)");
    p_create.set_defaults(func=handle_createkey);

    #mine
    p_mine = subparsers.add_parser("mine", help="Mine a block, using the first ./*.pem by default.");
    p_mine.add_argument("-u", "--use", help="Use specified keypair (path to .pem file)");
    p_mine.set_defaults(func=handle_mine);

    #transaction
    p_transaction = subparsers.add_parser("transaction", aliases=["tx"], help="Generate a transaction, using the first ./*.pem by default.");
    p_transaction.add_argument("-u", "--use", help="Use specified keypair (path to .pem file)");
    p_transaction.add_argument("-to", "--receiver", help="Send to specified public key (path to .pem file)");
    p_transaction.set_defaults(func=handle_tx);

    #deck
    p_deck = subparsers.add_parser("deck", help="Show all cards tied to the private key, using the first ./*.pem by default.");
    p_deck.add_argument("-u", "--use", help="Use specified keypair (path to .pem file)");
    p_deck.set_defaults(func=handle_deck);

    return parser;

def main():
    parser = build_parser();
    args = parser.parse_args();
    args.func(args);
    print(msg_array[0]);

if __name__ == "__main__":
    main();