"""
Moonstream crawlers CLI.
"""
import argparse
from distutils.util import strtobool
from enum import Enum
import json
import sys
import time
from typing import Iterator, List

from .ethereum import (
    crawl_blocks_executor,
    crawl_blocks,
    check_missing_blocks,
    get_latest_blocks,
    process_contract_deployments,
)
from .settings import MOONSTREAM_CRAWL_WORKERS


class ProcessingOrder(Enum):
    DESCENDING = 0
    ASCENDING = 1


def yield_blocks_numbers_lists(
    blocks_range_str: str,
    order: ProcessingOrder = ProcessingOrder.DESCENDING,
    block_step: int = 1000,
) -> Iterator[List[int]]:
    """
    Generate list of blocks.
    Block steps used to prevent long executor tasks and data loss possibility.
    """
    try:
        blocks_start_end = blocks_range_str.split("-")
        input_start_block = int(blocks_start_end[0])
        input_end_block = int(blocks_start_end[1])
    except Exception:
        print(
            "Wrong format provided, expected {bottom_block}-{top_block}, as ex. 105-340"
        )
        return

    starting_block = max(input_start_block, input_end_block)
    ending_block = min(input_start_block, input_end_block)

    stepsize = -1
    if order == ProcessingOrder.ASCENDING:
        starting_block = min(input_start_block, input_end_block)
        ending_block = max(input_start_block, input_end_block)
        stepsize = 1

    current_block = starting_block

    def keep_going() -> bool:
        if order == ProcessingOrder.ASCENDING:
            return current_block <= ending_block
        return current_block >= ending_block

    while keep_going():
        temp_ending_block = current_block + stepsize * block_step
        if order == ProcessingOrder.ASCENDING:
            if temp_ending_block > ending_block:
                temp_ending_block = ending_block + 1
        else:
            if temp_ending_block < ending_block:
                temp_ending_block = ending_block - 1
        blocks_numbers_list = list(range(current_block, temp_ending_block, stepsize))

        yield blocks_numbers_list

        if order == ProcessingOrder.ASCENDING:
            current_block += block_step
        else:
            current_block -= block_step


def ethcrawler_blocks_sync_handler(args: argparse.Namespace) -> None:
    """
    Synchronize latest Ethereum blocks with database.
    """
    starting_block: int = args.start
    while True:
        bottom_block_number, top_block_number = get_latest_blocks(
            bool(strtobool(args.transactions))
        )
        bottom_block_number = max(bottom_block_number + 1, starting_block)
        if bottom_block_number >= top_block_number:
            print(
                f"Synchronization is unnecessary for blocks {bottom_block_number}-{top_block_number - 1}"
            )
            time.sleep(20)
            continue

        for blocks_numbers_list in yield_blocks_numbers_lists(
            f"{bottom_block_number}-{top_block_number}",
            order=args.order,
        ):
            print(f"Adding blocks {blocks_numbers_list[-1]}-{blocks_numbers_list[0]}")
            # TODO(kompotkot): Set num_processes argument based on number of blocks to synchronize.
            crawl_blocks_executor(
                block_numbers_list=blocks_numbers_list,
                with_transactions=bool(strtobool(args.transactions)),
            )

        print(f"Synchronized blocks from {bottom_block_number} to {top_block_number}")
        time.sleep(10)


def ethcrawler_blocks_add_handler(args: argparse.Namespace) -> None:
    """
    Add blocks to moonstream database.
    """
    startTime = time.time()

    for blocks_numbers_list in yield_blocks_numbers_lists(args.blocks):
        print(f"Adding blocks {blocks_numbers_list[-1]}-{blocks_numbers_list[0]}")
        crawl_blocks_executor(
            block_numbers_list=blocks_numbers_list,
            with_transactions=bool(strtobool(args.transactions)),
        )

    print(f"Required {time.time() - startTime} with {MOONSTREAM_CRAWL_WORKERS} workers")


def ethcrawler_blocks_missing_handler(args: argparse.Namespace) -> None:
    startTime = time.time()
    missing_blocks_numbers_total = []
    for blocks_numbers_list in yield_blocks_numbers_lists(args.blocks):
        print(
            f"Check missing blocks from {blocks_numbers_list[0]} to {blocks_numbers_list[-1]}"
        )
        missing_blocks_numbers = check_missing_blocks(
            blocks_numbers=blocks_numbers_list,
        )
        missing_blocks_numbers_total.extend(missing_blocks_numbers)
    print(f"Found {len(missing_blocks_numbers_total)} missing blocks")

    time.sleep(5)

    if (len(missing_blocks_numbers_total)) > 0:
        if bool(strtobool(args.lazy)):
            print("Executed lazy block crawler")
            crawl_blocks(
                missing_blocks_numbers_total,
                with_transactions=bool(strtobool(args.transactions)),
                verbose=True,
            )
        else:
            crawl_blocks_executor(
                missing_blocks_numbers_total,
                with_transactions=bool(strtobool(args.transactions)),
                verbose=True,
            )
    print(
        f"Required {time.time() - startTime} with {MOONSTREAM_CRAWL_WORKERS} workers "
        f"for {len(missing_blocks_numbers_total)} missing blocks"
    )


def ethcrawler_contracts_update_handler(args: argparse.Namespace) -> None:
    results = process_contract_deployments()
    with args.outfile:
        json.dump(results, args.outfile)


def main() -> None:
    parser = argparse.ArgumentParser(description="Moonstream crawlers CLI")
    parser.set_defaults(func=lambda _: parser.print_help())
    subcommands = parser.add_subparsers(description="Crawlers commands")

    parser_ethcrawler = subcommands.add_parser(
        "ethcrawler", description="Ethereum crawler"
    )
    parser_ethcrawler.set_defaults(func=lambda _: parser_ethcrawler.print_help())
    subcommands_ethcrawler = parser_ethcrawler.add_subparsers(
        description="Ethereum crawler commands"
    )

    # Ethereum blocks parser
    parser_ethcrawler_blocks = subcommands_ethcrawler.add_parser(
        "blocks", description="Ethereum blocks commands"
    )
    parser_ethcrawler_blocks.set_defaults(
        func=lambda _: parser_ethcrawler_blocks.print_help()
    )
    subcommands_ethcrawler_blocks = parser_ethcrawler_blocks.add_subparsers(
        description="Ethereum blocks commands"
    )

    valid_processing_orders = {
        "asc": ProcessingOrder.ASCENDING,
        "desc": ProcessingOrder.DESCENDING,
    }

    def processing_order(raw_order: str) -> ProcessingOrder:
        if raw_order in valid_processing_orders:
            return valid_processing_orders[raw_order]
        raise ValueError(
            f"Invalid processing order ({raw_order}). Valid choices: {valid_processing_orders.keys()}"
        )

    parser_ethcrawler_blocks_sync = subcommands_ethcrawler_blocks.add_parser(
        "synchronize", description="Synchronize to latest ethereum block commands"
    )
    parser_ethcrawler_blocks_sync.add_argument(
        "-t",
        "--transactions",
        choices=["True", "False"],
        default="True",
        help="Add or not block transactions",
    )
    parser_ethcrawler_blocks_sync.add_argument(
        "-s",
        "--start",
        type=int,
        default=0,
        help="(Optional) Block to start synchronization from. Default: 0",
    )
    parser_ethcrawler_blocks_sync.add_argument(
        "--order",
        type=processing_order,
        default=ProcessingOrder.DESCENDING,
        help="Order in which to process blocks (choices: desc, asc; default: desc)",
    )
    parser_ethcrawler_blocks_sync.set_defaults(func=ethcrawler_blocks_sync_handler)

    parser_ethcrawler_blocks_add = subcommands_ethcrawler_blocks.add_parser(
        "add", description="Add ethereum blocks commands"
    )
    parser_ethcrawler_blocks_add.add_argument(
        "-b",
        "--blocks",
        required=True,
        help="List of blocks range in format {bottom_block}-{top_block}",
    )
    parser_ethcrawler_blocks_add.add_argument(
        "-t",
        "--transactions",
        choices=["True", "False"],
        default="True",
        help="Add or not block transactions",
    )
    parser_ethcrawler_blocks_add.set_defaults(func=ethcrawler_blocks_add_handler)

    parser_ethcrawler_blocks_missing = subcommands_ethcrawler_blocks.add_parser(
        "missing", description="Add missing ethereum blocks commands"
    )
    parser_ethcrawler_blocks_missing.add_argument(
        "-b",
        "--blocks",
        required=True,
        help="List of blocks range in format {bottom_block}-{top_block}",
    )
    parser_ethcrawler_blocks_missing.add_argument(
        "-t",
        "--transactions",
        choices=["True", "False"],
        default="True",
        help="Add or not block transactions",
    )
    parser_ethcrawler_blocks_missing.add_argument(
        "-l",
        "--lazy",
        choices=["True", "False"],
        default="False",
        help="Lazy block adding one by one",
    )
    parser_ethcrawler_blocks_missing.set_defaults(
        func=ethcrawler_blocks_missing_handler
    )

    parser_ethcrawler_contracts = subcommands_ethcrawler.add_parser(
        "contracts", description="Ethereum smart contract related crawlers"
    )
    parser_ethcrawler_contracts.set_defaults(
        func=lambda _: parser_ethcrawler_contracts.print_help()
    )
    subcommands_ethcrawler_contracts = parser_ethcrawler_contracts.add_subparsers(
        description="Ethereum contracts commands"
    )

    parser_ethcrawler_contracts_update = subcommands_ethcrawler_contracts.add_parser(
        "update",
        description="Update smart contract registry to include newly deployed smart contracts",
    )
    parser_ethcrawler_contracts_update.add_argument(
        "-o",
        "--outfile",
        type=argparse.FileType("w"),
        default=sys.stdout,
        help="(Optional) File to write new (transaction_hash, contract_address) pairs to",
    )
    parser_ethcrawler_contracts_update.set_defaults(
        func=ethcrawler_contracts_update_handler
    )

    args = parser.parse_args()
    args.func(args)


if __name__ == "__main__":
    main()