import json
import sys
from typing import List, Tuple, Dict

import click
import requests

from ..operation_strings import descriptions as op_desc


class Abort(click.ClickException):
    """Abort silently."""

    def __init__(self, exit_code=1):
        super().__init__('')
        self.exit_code = exit_code

    def show(self):
        pass


def print_colon_kv(pairs: List[Tuple[str, str]]):
    """
    Pretty-print a list of key-value pairs such that the key and value
    columns align.
    Example:
    key1:    value1
    key1000: value2
    """
    maxlen = max(len(key) for key, val in pairs)
    for key, val in pairs:
        click.echo(key + ': ', nl=False)
        extra_space = ' ' * (maxlen - len(key))
        click.echo(extra_space, nl=False)
        click.echo(val)


def handle_stream_response(resp: requests.Response, operations: List[str]) -> List[Dict]:
    """
    Print output to the console while operations are being streamed
    from the server over HTTP.
    Returns the parsed JSON data streamed from the server.
    """
    if resp.status_code != 200:
        click.echo('An error occurred:')
        click.echo(resp.text.rstrip())
        raise Abort()
    click.echo(op_desc[operations[0]] + '... ', nl=False)
    idx = 0
    data = []
    for line in resp.iter_lines(decode_unicode=True, chunk_size=8):
        d = json.loads(line)
        data.append(d)
        if d['status'] == 'aborted':
            click.echo(click.style('ABORTED', fg='red'))
            click.echo('The transaction was rolled back.')
            click.echo('The error was: ' + d['error'])
            click.echo('Please check the ceod logs.')
            sys.exit(1)
        elif d['status'] == 'completed':
            click.echo('Transaction successfully completed.')
            return data

        operation = d['operation']
        oper_failed = False
        err_msg = None
        prefix = 'failed_to_'
        if operation.startswith(prefix):
            operation = operation[len(prefix):]
            oper_failed = True
            # sometimes the operation looks like
            # "failed_to_do_something: error message"
            if ':' in operation:
                operation, err_msg = operation.split(': ', 1)

        while idx < len(operations) and operations[idx] != operation:
            click.echo('Skipped')
            idx += 1
            if idx == len(operations):
                break
            click.echo(op_desc[operations[idx]] + '... ', nl=False)
        if idx == len(operations):
            click.echo('Unrecognized operation: ' + operation)
            continue
        if oper_failed:
            click.echo(click.style('Failed', fg='red'))
            if err_msg is not None:
                click.echo('   Error message: ' + err_msg)
        else:
            click.echo(click.style('Done', fg='green'))
        idx += 1
        if idx < len(operations):
            click.echo(op_desc[operations[idx]] + '... ', nl=False)

    raise Exception('server response ended abruptly')


def handle_sync_response(resp: requests.Response):
    """
    Exit the program if the request was not successful.
    Returns the parsed JSON response.
    """
    if resp.status_code != 200:
        click.echo('An error occurred:')
        click.echo(resp.text.rstrip())
        raise Abort()
    return resp.json()