#!/usr/bin/env python3
# -*- coding: utf-8 -*-

"""
Helper for parsing AT command responses.
"""

import logging
from typing import TYPE_CHECKING

if TYPE_CHECKING:
    from m2m.serial.serial_port import SerialPort

logger = logging.getLogger('atparser')


class AtParser:
    """
    Parses responses from the serial port to determine command success/failure.
    """

    def __init__(self, serial_port: 'SerialPort'):
        self._port = serial_port
        self._last_response = b''

    @property
    def last_response(self) -> bytes:
        return self._last_response

    def read_ok(self, timeout: float = 1.0) -> bool:
        """
        Reads until a terminator is found and checks if it was 'OK'.
        """
        self._last_response = self._port.read_until(terminator=b'OK', timeout=timeout)
        # Check if the buffer *ends* with OK, or contains it on a line.
        # Strict check:
        lines = self._last_response.splitlines()
        for line in reversed(lines):
            line = line.strip()
            if line == b'OK':
                return True
            if line == b'ERROR' or b'CME ERROR' in line:
                return False
        return False

    def is_on(self, query_cmd: bytes, response_prefix: bytes, timeout: float = 1.0) -> bool:
        """
        Sends a query and checks if the value is '1'.
        Example: is_on(b'AT+CFUN?', b'+CFUN:')
        """
        self._port.send_cmd(query_cmd)
        response = self._port.read_until(timeout=timeout)
        self._last_response = response
        
        # Parse for prefix
        for line in response.splitlines():
            line = line.strip()
            if line.startswith(response_prefix):
                # +CFUN: 1
                try:
                    # Remove prefix, then split by comma if multiple params
                    # We assume the first param is the status
                    payload = line[len(response_prefix):].strip()
                    # Handle cases like "1" or "1,0"
                    val_str = payload.split(b',')[0]
                    return int(val_str) == 1
                except ValueError:
                    pass
        return False