/* Copyright 2017-2018 ccls Authors

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.
==============================================================================*/

#include "log.hh"
#include "pipeline.hh"
#include "platform.hh"
#include "serializer.hh"
#include "test.hh"
#include "working_files.hh"

#include <clang/Basic/Version.h>
#include <llvm/Support/CommandLine.h>
#include <llvm/Support/CrashRecoveryContext.h>
#include <llvm/Support/FileSystem.h>
#include <llvm/Support/Process.h>
#include <llvm/Support/Program.h>
#include <llvm/Support/Signals.h>

#include <rapidjson/document.h>
#include <rapidjson/error/en.h>

#include <stdio.h>
#include <stdlib.h>
#include <string>
#include <unordered_map>
#include <vector>

using namespace ccls;
using namespace llvm;
using namespace llvm::cl;

namespace ccls {
std::vector<std::string> g_init_options;
}

namespace {
OptionCategory C("ccls options");

opt<bool> opt_help("h", desc("Alias for -help"), cat(C));
opt<int> opt_verbose("v", desc("verbosity"), init(0), cat(C));
opt<std::string> opt_test_index("test-index", ValueOptional, init("!"),
                                desc("run index tests"), cat(C));

opt<std::string> opt_index("index",
                           desc("standalone mode: index a project and exit"),
                           value_desc("root"), cat(C));
list<std::string> opt_init("init", desc("extra initialization options in JSON"),
                           cat(C));
opt<std::string> opt_log_file("log-file", desc("log"), value_desc("filename"),
                              cat(C));
opt<std::string> opt_log_file_append("log-file-append", desc("log"),
                                     value_desc("filename"), cat(C));

void CloseLog() { fclose(ccls::log::file); }

} // namespace

int main(int argc, char **argv) {
  TraceMe();
  sys::PrintStackTraceOnErrorSignal(argv[0]);
  cl::SetVersionPrinter([](raw_ostream &OS) {
    OS << clang::getClangToolFullVersion("ccls") << "\n";
  });

  for (auto &I : TopLevelSubCommand->OptionsMap)
    if (I.second->Category != &C)
      I.second->setHiddenFlag(ReallyHidden);

  ParseCommandLineOptions(argc, argv,
                          "C/C++/Objective-C language server\n\n"
                          "See more on https://github.com/MaskRay/ccls/wiki");

  if (opt_help) {
    PrintHelpMessage();
    return 0;
  }
  ccls::log::verbosity = ccls::log::Verbosity(opt_verbose.getValue());

  pipeline::Init();
  const char *env = getenv("CCLS_CRASH_RECOVERY");
  if (!env || strcmp(env, "0") != 0)
    CrashRecoveryContext::Enable();

  bool language_server = true;

  if (opt_log_file.size() || opt_log_file_append.size()) {
    ccls::log::file = opt_log_file.size()
                          ? fopen(opt_log_file.c_str(), "wb")
                          : fopen(opt_log_file_append.c_str(), "ab");
    if (!ccls::log::file) {
      fprintf(
          stderr, "failed to open %s\n",
          (opt_log_file.size() ? opt_log_file : opt_log_file_append).c_str());
      return 2;
    }
    setbuf(ccls::log::file, NULL);
    atexit(CloseLog);
  }

  if (opt_test_index != "!") {
    language_server = false;
    if (!ccls::RunIndexTests(opt_test_index, sys::Process::StandardInIsUserInput()))
      return 1;
  }

  if (language_server) {
    if (!opt_init.empty()) {
      // We check syntax error here but override client-side
      // initializationOptions in messages/initialize.cc
      g_init_options = opt_init;
      rapidjson::Document reader;
      for (const std::string &str : g_init_options) {
        rapidjson::ParseResult ok = reader.Parse(str.c_str());
        if (!ok) {
          fprintf(stderr, "Failed to parse --init as JSON: %s (%zd)\n",
                  rapidjson::GetParseError_En(ok.Code()), ok.Offset());
          return 1;
        }
        JsonReader json_reader{&reader};
        try {
          Config config;
          Reflect(json_reader, config);
        } catch (std::invalid_argument &e) {
          fprintf(stderr, "Failed to parse --init %s, expected %s\n",
                  static_cast<JsonReader &>(json_reader).GetPath().c_str(),
                  e.what());
          return 1;
        }
      }
    }

    sys::ChangeStdinToBinary();
    sys::ChangeStdoutToBinary();
    if (opt_index.size()) {
      SmallString<256> Root(opt_index);
      sys::fs::make_absolute(Root);
      pipeline::Standalone(Root.str());
    } else {
      // The thread that reads from stdin and dispatchs commands to the main
      // thread.
      pipeline::LaunchStdin();
      // The thread that writes responses from the main thread to stdout.
      pipeline::LaunchStdout();
      // Main thread which also spawns indexer threads upon the "initialize"
      // request.
      pipeline::MainLoop();
    }
  }

  return 0;
}