#!/usr/bin/env python3
#
# Copyright (C) 2022 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.
#

# A tool that can feed data into GNSS HAL over virtio-console
# This tool can be invoked as gnss_replay.py -s <socket> -i <input>
# where <socket> is the host-side of a UNIX domain socket that backs
# virtio-console GNSS vport and <input> is a log file generated by
# GnssLogger or equivalent tooling

import argparse
import sys
import socket
import time

class DataStore(object):
    def __init__(self, prefix, lines):
        self.idx = 0
        self.lines = []
        for line in lines:
            if line.startswith(prefix):
                self.lines.append(line.strip('\n'))

    def next(self):
        line = ''
        if len(self.lines) > 0:
            line = self.lines[self.idx]
            self.idx = (self.idx + 1) % len(self.lines)
        return line

    def __str__(self):
        return str(self.lines)

def load(input):
    with open(input) as f:
        lines = f.readlines()
        return {'locations' : DataStore('Fix', lines),
                'measurements' : DataStore('Raw', lines)}

class CommandLoop(object):
    def __init__(self, socket):
        self.socket = socket
        self.commands = {}

    def command(self, action, reaction):
        self.commands[action] = reaction

    def loop(self):
        while True:
            inp = self.socket.recv(128)
            reaction = self.commands.get(inp, None)
            if reaction:
                response = reaction() + '\n\n\n\n'
                self.socket.send(str.encode(response))
            else:
                print("Unknown command '%s'" % inp)
                self.socket.send(b'\n\n\n\n')

def main():
    parser = argparse.ArgumentParser(description="GNSS mock host agent")
    parser.add_argument('--socket', '-s', action='store', required=True, help='The UNIX socket to interact with')
    parser.add_argument('--input', '-i', action='store', required=True, help='The file with fix information to send over')

    args = parser.parse_args()

    sk = socket.socket(socket.AF_UNIX, socket.SOCK_SEQPACKET)
    sk.connect(args.socket)

    data = load(args.input)

    loop = CommandLoop(sk)
    loop.command(b'CMD_GET_LOCATION', lambda: data['locations'].next())
    loop.command(b'CMD_GET_RAWMEASUREMENT', lambda: data['measurements'].next())

    loop.loop()

if __name__ == "__main__":
    main()