import os
import sys
import time
import requests
from typing import Optional
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.primitives import serialization


sys.path.insert(0, os.path.abspath(os.path.join(os.path.dirname(__file__), "wikideck")));

from Mine.Block import Block
from Mine.Transaction import Transaction

WIKIDECK_URL = os.getenv('WIKIDECK_URL', 'http://localhost:8080/');


rsa_private_key: Optional[rsa.RSAPrivateKey] = None;
msg_array: list[str] = [""];
private_key_file: str = "private_key.pem";



def main():

    while True:

        if (msg_array[0]):
            print(f"Last Action: {msg_array[0]}");

        print("\n--- Wikideck CLI ---");
        print("1. Create RSA Keypair");
        print("2. Save RSA Keypair");
        print("3. Load RSA Keypair");
        print("4. Mine a Block");
        print("5. Generate a Transaction");
        print("6. View Deck");
        print("0. Exit");
        print("\n-------------------");

        try:
            choice: int = int(input("Select an option: ").strip());
        except ValueError:
            msg_array[0] = "Invalid Input. Please Choose a Number Between 0-6.";
            clear_console();
            continue;


        if choice == 0:
            break;
        elif choice == 1: 
            opt_generate_private_key(65537, 2048);
        elif choice == 2:
            opt_save_private_key();
        elif choice == 3:
            opt_load_private_key();
        elif choice == 4:
            opt_mine_block();
        elif choice == 5:
            opt_generate_transaction();
        elif choice == 6:
            opt_view_deck();
        else:
            msg_array[0] = "Invalid Input. Please Choose a Number Between 0-6.";
        
        clear_console();

def opt_generate_private_key(exponent, size):
    global rsa_private_key;
    rsa_private_key = rsa.generate_private_key(
                public_exponent = exponent,
                key_size = size,
            )
    msg_array[0] = "RSA Keypair Generated";

def opt_save_private_key():
    if rsa_private_key is None:
        msg_array[0] = "No RSA Keypair to Save. Please Generate one first.";
        return None;
    else:
        with open(private_key_file, "wb") as file:
            pem = rsa_private_key.private_bytes(
                        encoding=serialization.Encoding.PEM,
                        format=serialization.PrivateFormat.TraditionalOpenSSL,
                        encryption_algorithm=serialization.NoEncryption()
                    )
            file.write(pem);
            msg_array[0] = f"RSA Private Key Saved to {private_key_file}";

def opt_load_private_key():
    global rsa_private_key;
    if not os.path.exists(private_key_file):
        msg_array[0] = f"No saved key found ({private_key_file} missing)";
        return None;

    with open(private_key_file, "rb") as file:
        rsa_private_key = serialization.load_pem_private_key(
                    file.read(),
                    password=None,
                )
        msg_array[0] = f"RSA Private Key Loaded From {private_key_file}";

def opt_mine_block():

    global rsa_private_key;


    if rsa_private_key is None:
        msg_array[0] = "You must load or generate an RSA keypair first.";
        return;

    try:
        response = requests.get(f"{WIKIDECK_URL}/blocks");
        if response.status_code != 200:
            msg_array[0] = f"Failed to fetch block to mine: {response.status_code}";
            return;

        block_to_mine = Block(data = response.json());
        block_to_mine.mine(rsa_private_key);

        response = requests.post(f"{WIKIDECK_URL}/blocks", json=block_to_mine.as_dict());
        if response.status_code == 200:
            msg_array[0] = "Block successfully mined and submitted";
        else:
            msg_array[0] = f"Failed to submit mined block: {response.status_code}";
            
    except Exception as e:
        msg_array[0] = f"Error during mining: {str(e)}";

def opt_generate_transaction():
    global rsa_private_key;
    
    if rsa_private_key is None:
        msg_array[0] = "You must load or generate an RSA keypair first.";
        return;

    print("\nPaste the recipient's RSA Public Key (PEM format). End with an Empty Line (Press enter twice): ");
    lines = [];

    while True:
        line = input();
        if not line.strip():
            break;
        lines.append(line);

    receiver_pem = "\n".join(lines);

    try:
        receiver_key = serialization.load_pem_public_key(receiver_pem.encode("utf-8"));
    except Exception:
        msg_array[0] = "Invalid public key format";
        return;

    try:
                
        cards = fetch_cards_json(rsa_private_key);

        if not cards:
            msg_array[0] = "You have no cards to send";
            return;

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


        try:
            index: int = int(input("Select a card number to send: ").strip()) - 1;
            
            if not (0 <= index < len(cards)):
                raise ValueError;
        except ValueError:
            msg_array[0] = "Invalid card selection";
            return;

        selected_card = cards[index];

        tx = Transaction(
                    cardId = selected_card['cardId'],
                    sender = rsa_private_key.public_key(),
                    receiver=receiver_key,
                    authorPrivateKey=rsa_private_key
                );

        response = requests.post(f"{WIKIDECK_URL}/transactions", json=tx.as_dict());

        if response.status_code != 200:
            msg_array[0] = f"Transaction failed: {response.status_code}";
        else:
            msg_array[0] = "Transaction submitted successfully";
    
    except Exception as e:
        msg_array[0] = f"Error creating transaction: {str(e)}";

def opt_view_deck():

    global rsa_private_key;
    if rsa_private_key is None:
        msg_array[0] = "You must load or generate an RSA keypair first.";
        return;

    try:
        cards = fetch_cards_json(rsa);


        if len(cards) <= 0:
            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']}");

    except Exception as e:
        msg_array[0] = f"Error fetching cards: {str(e)}";

def fetch_cards_json(rsa):
        pem = rsa.public_key().public_bytes(
                    encoding=serialization.Encoding.PEM,
                    format=serialization.PublicFormat.SubjectPublicKeyInfo
                ).decode("utf-8");

        response = requests.get(f"{WIKIDECK_URL}/cards", params={"publicKey": pem});

        if response.status_code != 200:
            msg_array[0] = f"Failed to fetch cards: {response.status_code}";
            return;

        cards = response.json();
        return cards;


def clear_console():
    os.system('cls' if os.name == 'nt' else 'clear');

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