#!/usr/bin/python
# Copyright (C) 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 argparse

from google.protobuf import descriptor, descriptor_pb2, message_factory, reflection
from google.protobuf.pyext import _message

CLONE_THREAD = 0x00010000


class Trace(object):
  def __init__(self, trace):
    self.trace = trace
    self.proc_map = {}
    self.proc_map[0] = "idle_thread"

  def add_system_info(self, arch=None):
    self.packet = self.trace.packet.add()
    self.packet.system_info.utsname.machine = arch

  def add_ftrace_packet(self, cpu):
    self.packet = self.trace.packet.add()
    self.packet.ftrace_events.cpu = cpu

  def __add_ftrace_event(self, ts, tid):
    ftrace = self.packet.ftrace_events.event.add()
    ftrace.timestamp = ts
    ftrace.pid = tid
    return ftrace

  def add_rss_stat(self, ts, tid, member, size):
    ftrace = self.__add_ftrace_event(ts, tid)
    rss_stat = ftrace.rss_stat
    rss_stat.member = member
    rss_stat.size = size

  def add_oom_score_update(self, ts, oom_score_adj, pid):
    ftrace = self.__add_ftrace_event(ts, pid)
    oom_score = ftrace.oom_score_adj_update
    oom_score.comm = self.proc_map[pid]
    oom_score.oom_score_adj = oom_score_adj
    oom_score.pid = pid

  def add_sched(self, ts, prev_pid, next_pid, prev_comm=None, next_comm=None):
    ftrace = self.__add_ftrace_event(ts, 0)
    ss = ftrace.sched_switch
    ss.prev_comm = prev_comm or self.proc_map[prev_pid]
    ss.prev_pid = prev_pid
    ss.next_pid = next_pid
    ss.next_comm = next_comm or self.proc_map[next_pid]

  def add_cpufreq(self, ts, freq, cpu):
    ftrace = self.__add_ftrace_event(ts, 0)
    cpufreq = ftrace.cpu_frequency
    cpufreq.state = freq
    cpufreq.cpu_id = cpu

  def add_kernel_lmk(self, ts, tid):
    ftrace = self.__add_ftrace_event(ts, tid)
    lowmemory_kill = ftrace.lowmemory_kill
    lowmemory_kill.pid = tid

  def add_sys_enter(self, ts, tid, id):
    ftrace = self.__add_ftrace_event(ts, tid)
    sys_enter = ftrace.sys_enter
    sys_enter.id = id

  def add_sys_exit(self, ts, tid, id, ret):
    ftrace = self.__add_ftrace_event(ts, tid)
    sys_exit = ftrace.sys_exit
    sys_exit.id = id
    sys_exit.ret = ret

  def add_newtask(self, ts, tid, new_tid, new_comm, flags):
    ftrace = self.__add_ftrace_event(ts, tid)
    newtask = ftrace.task_newtask
    newtask.pid = new_tid
    newtask.comm = new_comm
    newtask.clone_flags = flags

  def add_process_tree_packet(self, ts=None):
    self.packet = self.trace.packet.add()
    if ts is not None:
      self.packet.timestamp = ts

  def add_process(self, pid, ppid, cmdline):
    process = self.packet.process_tree.processes.add()
    process.pid = pid
    process.ppid = ppid
    process.cmdline.append(cmdline)
    self.proc_map[pid] = cmdline

  def add_thread(self, tid, tgid, cmdline):
    thread = self.packet.process_tree.threads.add()
    thread.tid = tid
    thread.tgid = tgid
    self.proc_map[tid] = cmdline


def create_trace():
  parser = argparse.ArgumentParser()
  parser.add_argument(
      'trace_descriptor', type=str, help='location of trace descriptor')
  args = parser.parse_args()

  with open(args.trace_descriptor, "rb") as t:
    fileContent = t.read()

  file_desc_set_pb2 = descriptor_pb2.FileDescriptorSet()
  file_desc_set_pb2.MergeFromString(fileContent)

  desc_by_path = {}
  for f_desc_pb2 in file_desc_set_pb2.file:
    f_desc_pb2_encode = f_desc_pb2.SerializeToString()
    f_desc = descriptor.FileDescriptor(
        name=f_desc_pb2.name,
        package=f_desc_pb2.package,
        serialized_pb=f_desc_pb2_encode)

    for desc in f_desc.message_types_by_name.values():
      desc_by_path[desc.full_name] = desc

  trace = message_factory.MessageFactory().GetPrototype(
      desc_by_path["perfetto.protos.Trace"])()
  return Trace(trace)