#include "cmake.h"
#include "compile_commands.h"
#include "config.h"
#include "dialogs.h"
#include "filesystem.h"
#include "terminal.h"
#include <regex>

CMake::CMake(const boost::filesystem::path &path) {
  const auto find_cmake_project = [](const boost::filesystem::path &cmake_path) {
    for(auto &line : filesystem::read_lines(cmake_path)) {
      const static std::regex project_regex(R"(^ *project *\(.*\r?$)", std::regex::icase);
      std::smatch sm;
      if(std::regex_match(line, sm, project_regex))
        return true;
    }
    return false;
  };

  auto search_path = boost::filesystem::is_directory(path) ? path : path.parent_path();
  while(true) {
    auto search_cmake_path = search_path / "CMakeLists.txt";
    if(boost::filesystem::exists(search_cmake_path)) {
      paths.emplace(paths.begin(), search_cmake_path);
      if(find_cmake_project(search_cmake_path)) {
        project_path = search_path;
        break;
      }
    }
    if(search_path == search_path.root_directory())
      break;
    search_path = search_path.parent_path();
  }
}

bool CMake::update_default_build(const boost::filesystem::path &default_build_path, bool force) {
  if(project_path.empty() || !boost::filesystem::exists(project_path / "CMakeLists.txt") || default_build_path.empty())
    return false;

  if(!boost::filesystem::exists(default_build_path)) {
    boost::system::error_code ec;
    boost::filesystem::create_directories(default_build_path, ec);
    if(ec) {
      Terminal::get().print("Error: could not create " + default_build_path.string() + ": " + ec.message() + "\n", true);
      return false;
    }
  }

  if(!force && boost::filesystem::exists(default_build_path / "compile_commands.json"))
    return true;

  auto compile_commands_path = default_build_path / "compile_commands.json";
  Dialog::Message message("Creating/updating default build");
  auto exit_status = Terminal::get().process(Config::get().project.cmake.command + ' ' +
                                                 filesystem::escape_argument(project_path.string()) + " -DCMAKE_EXPORT_COMPILE_COMMANDS=ON", default_build_path);
  message.hide();
  if(exit_status == EXIT_SUCCESS) {
#ifdef _WIN32 //Temporary fix to MSYS2's libclang
    auto compile_commands_file = filesystem::read(compile_commands_path);
    auto replace_drive = [&compile_commands_file](const std::string &param) {
      size_t pos = 0;
      auto param_size = param.length();
      while((pos = compile_commands_file.find(param + "/", pos)) != std::string::npos) {
        if(pos + param_size + 1 < compile_commands_file.size())
          compile_commands_file.replace(pos, param_size + 2, param + compile_commands_file[pos + param_size + 1] + ":");
        else
          break;
      }
    };
    replace_drive("-I");
    replace_drive("-isystem ");
    filesystem::write(compile_commands_path, compile_commands_file);
#endif
    return true;
  }
  return false;
}

bool CMake::update_debug_build(const boost::filesystem::path &debug_build_path, bool force) {
  if(project_path.empty() || !boost::filesystem::exists(project_path / "CMakeLists.txt") || debug_build_path.empty())
    return false;

  if(!boost::filesystem::exists(debug_build_path)) {
    boost::system::error_code ec;
    boost::filesystem::create_directories(debug_build_path, ec);
    if(ec) {
      Terminal::get().print("Error: could not create " + debug_build_path.string() + ": " + ec.message() + "\n", true);
      return false;
    }
  }

  if(!force && boost::filesystem::exists(debug_build_path / "CMakeCache.txt"))
    return true;

  Dialog::Message message("Creating/updating debug build");
  auto exit_status = Terminal::get().process(Config::get().project.cmake.command + ' ' +
                                                 filesystem::escape_argument(project_path.string()) + " -DCMAKE_BUILD_TYPE=Debug", debug_build_path);
  message.hide();
  if(exit_status == EXIT_SUCCESS)
    return true;
  return false;
}

boost::filesystem::path CMake::get_executable(const boost::filesystem::path &build_path, const boost::filesystem::path &file_path) {
  // CMake does not store in compile_commands.json if an object is part of an executable or not.
  // Therefore, executables are first attempted found in the cmake files. These executables
  // are then used to identify if a file in compile_commands.json is part of an executable or not

  auto parameters = get_functions_parameters("add_executable");

  std::vector<boost::filesystem::path> cmake_executables;
  for(auto &parameter : parameters) {
    if(parameter.second.size() > 1 && parameter.second[0].size() > 0 && parameter.second[0].compare(0, 2, "${") != 0) {
      auto executable = (parameter.first.parent_path() / parameter.second[0]).string();
      auto project_path_str = project_path.string();
      size_t pos = executable.find(project_path_str);
      if(pos != std::string::npos)
        executable.replace(pos, project_path_str.size(), build_path.string());
      cmake_executables.emplace_back(executable);
    }
  }


  CompileCommands compile_commands(build_path);
  std::vector<std::pair<boost::filesystem::path, boost::filesystem::path>> command_files_and_maybe_executables;
  for(auto &command : compile_commands.commands) {
    auto command_file = filesystem::get_normal_path(command.file);
    auto values = command.parameter_values("-o");
    if(!values.empty()) {
      size_t pos;
      values[0].erase(0, 11);
      if((pos = values[0].find(".dir")) != std::string::npos) {
        auto executable = command.directory / values[0].substr(0, pos);
        command_files_and_maybe_executables.emplace_back(command_file, executable);
      }
    }
  }

  size_t best_match_size = -1;
  boost::filesystem::path best_match_executable;

  for(auto &cmake_executable : cmake_executables) {
    for(auto &command_file_and_maybe_executable : command_files_and_maybe_executables) {
      auto &command_file = command_file_and_maybe_executable.first;
      auto &maybe_executable = command_file_and_maybe_executable.second;
      if(cmake_executable == maybe_executable) {
        if(command_file == file_path)
          return maybe_executable;
        auto command_file_directory = command_file.parent_path();
        if(filesystem::file_in_path(file_path, command_file_directory)) {
          auto size = static_cast<size_t>(std::distance(command_file_directory.begin(), command_file_directory.end()));
          if(best_match_size == static_cast<size_t>(-1) || best_match_size < size) {
            best_match_size = size;
            best_match_executable = maybe_executable;
          }
        }
      }
    }
  }
  if(!best_match_executable.empty())
    return best_match_executable;

  for(auto &command_file_and_maybe_executable : command_files_and_maybe_executables) {
    auto &command_file = command_file_and_maybe_executable.first;
    auto &maybe_executable = command_file_and_maybe_executable.second;
    if(command_file == file_path)
      return maybe_executable;
    auto command_file_directory = command_file.parent_path();
    if(filesystem::file_in_path(file_path, command_file_directory)) {
      auto size = static_cast<size_t>(std::distance(command_file_directory.begin(), command_file_directory.end()));
      if(best_match_size == static_cast<size_t>(-1) || best_match_size < size) {
        best_match_size = size;
        best_match_executable = maybe_executable;
      }
    }
  }
  return best_match_executable;
}

void CMake::read_files() {
  for(auto &path : paths)
    files.emplace_back(filesystem::read(path));
}

void CMake::remove_tabs() {
  for(auto &file : files) {
    for(auto &chr : file) {
      if(chr == '\t')
        chr = ' ';
    }
  }
}

void CMake::remove_comments() {
  for(auto &file : files) {
    size_t pos = 0;
    size_t comment_start;
    bool inside_comment = false;
    while(pos < file.size()) {
      if(!inside_comment && file[pos] == '#') {
        comment_start = pos;
        inside_comment = true;
      }
      if(inside_comment && file[pos] == '\n') {
        file.erase(comment_start, pos - comment_start);
        pos -= pos - comment_start;
        inside_comment = false;
      }
      pos++;
    }
    if(inside_comment)
      file.erase(comment_start);
  }
}

void CMake::remove_newlines_inside_parentheses() {
  for(auto &file : files) {
    size_t pos = 0;
    bool inside_para = false;
    bool inside_quote = false;
    char last_char = 0;
    while(pos < file.size()) {
      if(!inside_quote && file[pos] == '"' && last_char != '\\')
        inside_quote = true;
      else if(inside_quote && file[pos] == '"' && last_char != '\\')
        inside_quote = false;

      else if(!inside_quote && file[pos] == '(')
        inside_para = true;
      else if(!inside_quote && file[pos] == ')')
        inside_para = false;

      else if(inside_para && file[pos] == '\n')
        file.replace(pos, 1, 1, ' ');
      last_char = file[pos];
      pos++;
    }
  }
}

void CMake::parse_variable_parameters(std::string &data) {
  size_t pos = 0;
  bool inside_quote = false;
  char last_char = 0;
  while(pos < data.size()) {
    if(!inside_quote && data[pos] == '"' && last_char != '\\') {
      inside_quote = true;
      data.erase(pos, 1); //TODO: instead remove quote-mark if pasted into a quote, for instance: "test${test}test"<-remove quotes from ${test}
      pos--;
    }
    else if(inside_quote && data[pos] == '"' && last_char != '\\') {
      inside_quote = false;
      data.erase(pos, 1); //TODO: instead remove quote-mark if pasted into a quote, for instance: "test${test}test"<-remove quotes from ${test}
      pos--;
    }
    else if(!inside_quote && data[pos] == ' ' && pos + 1 < data.size() && data[pos + 1] == ' ') {
      data.erase(pos, 1);
      pos--;
    }

    if(pos != static_cast<size_t>(-1))
      last_char = data[pos];
    pos++;
  }
  for(auto &var : variables) {
    auto pos = data.find("${" + var.first + '}');
    while(pos != std::string::npos) {
      data.replace(pos, var.first.size() + 3, var.second);
      pos = data.find("${" + var.first + '}');
    }
  }

  //Remove variables we do not know:
  pos = data.find("${");
  auto pos_end = data.find('}', pos + 2);
  while(pos != std::string::npos && pos_end != std::string::npos) {
    data.erase(pos, pos_end - pos + 1);
    pos = data.find("${");
    pos_end = data.find('}', pos + 2);
  }
}

void CMake::parse() {
  read_files();
  remove_tabs();
  remove_comments();
  remove_newlines_inside_parentheses();
  parsed = true;
}

std::vector<std::string> CMake::get_function_parameters(std::string &data) {
  std::vector<std::string> parameters;
  size_t pos = 0;
  size_t parameter_pos = 0;
  bool inside_quote = false;
  char last_char = 0;
  while(pos < data.size()) {
    if(!inside_quote && data[pos] == '"' && last_char != '\\') {
      inside_quote = true;
      data.erase(pos, 1);
      pos--;
    }
    else if(inside_quote && data[pos] == '"' && last_char != '\\') {
      inside_quote = false;
      data.erase(pos, 1);
      pos--;
    }
    else if(!inside_quote && pos + 1 < data.size() && data[pos] == ' ' && data[pos + 1] == ' ') {
      data.erase(pos, 1);
      pos--;
    }
    else if(!inside_quote && data[pos] == ' ') {
      parameters.emplace_back(data.substr(parameter_pos, pos - parameter_pos));
      if(pos + 1 < data.size())
        parameter_pos = pos + 1;
    }

    if(pos != static_cast<size_t>(-1))
      last_char = data[pos];
    pos++;
  }
  parameters.emplace_back(data.substr(parameter_pos));
  for(auto &var : variables) {
    for(auto &parameter : parameters) {
      auto pos = parameter.find("${" + var.first + '}');
      while(pos != std::string::npos) {
        parameter.replace(pos, var.first.size() + 3, var.second);
        pos = parameter.find("${" + var.first + '}');
      }
    }
  }
  return parameters;
}

std::vector<std::pair<boost::filesystem::path, std::vector<std::string>>> CMake::get_functions_parameters(const std::string &name) {
  const std::regex function_regex("^ *" + name + R"( *\( *(.*)\) *\r?$)", std::regex::icase);
  variables.clear();
  if(!parsed)
    parse();
  std::vector<std::pair<boost::filesystem::path, std::vector<std::string>>> functions;
  for(size_t c = 0; c < files.size(); ++c) {
    size_t pos = 0;
    while(pos < files[c].size()) {
      auto start_line = pos;
      auto end_line = files[c].find('\n', start_line);
      if(end_line == std::string::npos)
        end_line = files[c].size();
      if(end_line > start_line) {
        auto line = files[c].substr(start_line, end_line - start_line);
        std::smatch sm;
        const static std::regex set_regex(R"(^ *set *\( *([A-Za-z_][A-Za-z_0-9]*) +(.*)\) *\r?$)", std::regex::icase);
        const static std::regex project_regex(R"(^ *project *\( *([^ ]+).*\) *\r?$)", std::regex::icase);
        if(std::regex_match(line, sm, set_regex)) {
          auto data = sm[2].str();
          while(data.size() > 0 && data.back() == ' ')
            data.pop_back();
          parse_variable_parameters(data);
          variables[sm[1].str()] = data;
        }
        else if(std::regex_match(line, sm, project_regex)) {
          auto data = sm[1].str();
          parse_variable_parameters(data);
          variables["CMAKE_PROJECT_NAME"] = data; //TODO: is this variable deprecated/non-standard?
          variables["PROJECT_NAME"] = data;
        }
        if(std::regex_match(line, sm, function_regex)) {
          auto data = sm[1].str();
          while(data.size() > 0 && data.back() == ' ')
            data.pop_back();
          auto parameters = get_function_parameters(data);
          functions.emplace_back(paths[c], parameters);
        }
      }
      pos = end_line + 1;
    }
  }
  return functions;
}