#!/usr/bin/env python3
# Copyright 2018 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may not
# use this file except in compliance with the License. You may obtain a copy of
# the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations under
# the License.

import base64
import logging
import os
import subprocess
import sys
import tempfile
from distutils.spawn import find_executable
import google.protobuf.text_format as text_format
from importlib import import_module

def compile_proto(proto_path, output_dir):
    """Invoke Protocol Compiler to generate python from given source .proto."""
    # Find compiler path
    protoc = None
    if 'PROTOC' in os.environ and os.path.exists(os.environ['PROTOC']):
        protoc = os.environ['PROTOC']
    if not protoc:
        protoc = find_executable('protoc')
    if not protoc:
        logging.error(
            "Cannot find Protobuf compiler (>=3.0.0), please install"
            "protobuf-compiler package. Prefer copying from <top>/prebuilts/tools"
        )
        logging.error("    prebuilts/tools/linux-x86_64/protoc/bin/protoc")
        logging.error("If prebuilts are not available, use apt-get:")
        logging.error("    sudo apt-get install protobuf-compiler")
        return None
    # Validate input proto path
    if not os.path.exists(proto_path):
        logging.error('Can\'t find required file: %s\n' % proto_path)
        return None
    # Validate output py-proto path
    if not os.path.exists(output_dir):
        os.mkdirs(output_dir)
    elif not os.path.isdir(output_dir):
        logging.error("Output path is not a valid directory: %s" %
                      (output_dir))
        return None
    input_dir = os.path.dirname(proto_path)
    output_filename = os.path.basename(proto_path).replace('.proto', '_pb2.py')
    output_path = os.path.join(output_dir, output_filename)
    protoc_command = [
        protoc, '-I=%s' % (input_dir), '--python_out=%s' % (output_dir),
        proto_path
    ]
    if subprocess.call(protoc_command, stderr=subprocess.STDOUT) != 0:
        logging.error("Fail to compile proto")
        return None
    output_module_name = os.path.splitext(output_filename)[0]
    return output_module_name


def compile_import_proto(output_dir, proto_path):
    """
    Compile protobuf from PROTO_PATH and put the result in OUTPUT_DIR.
    Return the imported module to caller.
    :param output_dir: To store generated python proto library
    :param proto_path: Path to the .proto file that needs to be compiled
    :return: python proto module
    """
    output_module_name = compile_proto(proto_path, output_dir)
    if not output_module_name:
        return None
    sys.path.append(output_dir)
    output_module = None
    try:
        output_module = import_module(output_module_name)
    except ImportError:
        logging.error("Cannot import generated py-proto %s" %
                      (output_module_name))
    return output_module


def parse_proto_to_ascii(binary_proto_msg):
    """
    Parse binary protobuf message to human readable ascii string
    :param binary_proto_msg:
    :return: ascii string of the message
    """
    return text_format.MessageToString(binary_proto_msg)

def dump_metrics():
    os.system('adb wait-for-device')
    p = subprocess.Popen("adb shell dumpsys bluetooth_manager --proto-bin",
        shell=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
        stdin=subprocess.PIPE)
    return p.communicate()

def get_bluetooth_metrics(proto_native_str_64, bluetooth_proto_module):
    bluetooth_log = bluetooth_proto_module.BluetoothLog()
    proto_native_str = base64.b64decode(proto_native_str_64)
    bluetooth_log.MergeFromString(proto_native_str)
    return bluetooth_log

def main():
    root = logging.getLogger()
    root.setLevel(logging.DEBUG)
    log_handler = logging.StreamHandler(sys.stderr)
    log_handler.setLevel(logging.DEBUG)
    formatter = logging.Formatter(
        "%(asctime)s %(levelname)s %(message)s")
    log_handler.setFormatter(formatter)
    root.addHandler(log_handler)
    if len(sys.argv) < 2:
        logging.error("Not enough arguments. Need at least 2")
        logging.error("Usage: " + sys.argv[0] + " <path_to_metric_proto>")
        sys.exit(1)
    if sys.argv[1] == "-h":
        logging.info("Usage: " + sys.argv[0] + " <path_to_metric_proto>")
        logging.info("Requires Protobuf compiler, protoc, version >=3.0.0")
        sys.exit(0)
    bluetooth_proto_module = compile_import_proto(tempfile.gettempdir(),
        sys.argv[1])
    if not bluetooth_proto_module:
        logging.error("Cannot compile " + sys.argv[1])
        sys.exit(1)
    stdout, stderr = dump_metrics()
    stdout = stdout.strip()
    stderr = stderr.strip()
    bluetooth_log = get_bluetooth_metrics(stdout, bluetooth_proto_module)
    bluetooth_log_ascii = parse_proto_to_ascii(bluetooth_log)
    print(bluetooth_log_ascii)

if __name__ == "__main__":
    main()