#include "terminal.h"
#include <iostream>
#include "logging.h"
#include "singletons.h"
#include <unistd.h>
#include <sys/wait.h>

#include <iostream> //TODO: remove
using namespace std; //TODO: remove

const ssize_t buffer_size=131072;

//A working implementation of popen3, with all pipes getting closed properly. 
//TODO: Eidheim is going to publish this one on his github, along with example uses
pid_t popen3(const std::string &command, const std::string &path, int *stdin_fd, int *stdout_fd, int *stderr_fd) {
  pid_t pid;
  int stdin_p[2], stdout_p[2], stderr_p[2];

  if(stdin_fd!=nullptr && pipe(stdin_p)!=0) {
    close(stdin_p[0]);
    close(stdin_p[1]);
    return -1;
  }
  if(stdout_fd!=nullptr && pipe(stdout_p)!=0) {
    if(stdin_fd!=nullptr) close(stdin_p[0]);
    if(stdin_fd!=nullptr) close(stdin_p[1]);
    close(stdout_p[0]);
    close(stdout_p[1]);
    return -1;
  }
  if(stderr_fd!=nullptr && pipe(stderr_p)!=0) {
    if(stdin_fd!=nullptr) close(stdin_p[0]);
    if(stdin_fd!=nullptr) close(stdin_p[1]);
    if(stdout_fd!=nullptr) close(stdout_p[0]);
    if(stdout_fd!=nullptr) close(stdout_p[1]);
    close(stderr_p[0]);
    close(stderr_p[1]);
    return -1;
  }
  
  pid = fork();

  if (pid < 0) {
    if(stdin_fd!=nullptr) close(stdin_p[0]);
    if(stdin_fd!=nullptr) close(stdin_p[1]);
    if(stdout_fd!=nullptr) close(stdout_p[0]);
    if(stdout_fd!=nullptr) close(stdout_p[1]);
    if(stderr_fd!=nullptr) close(stderr_p[0]);
    if(stderr_fd!=nullptr) close(stderr_p[1]);
    return pid;
  }
  else if (pid == 0) {
    if(stdin_fd!=nullptr) close(stdin_p[1]);
    if(stdout_fd!=nullptr) close(stdout_p[0]);
    if(stderr_fd!=nullptr) close(stderr_p[0]);
    if(stdin_fd!=nullptr) dup2(stdin_p[0], 0);
    if(stdout_fd!=nullptr) dup2(stdout_p[1], 1);
    if(stderr_fd!=nullptr) dup2(stderr_p[1], 2);

    setpgid(0, 0);
    //TODO: See here on how to emulate tty for colors: http://stackoverflow.com/questions/1401002/trick-an-application-into-thinking-its-stdin-is-interactive-not-a-pipe
    //TODO: One solution is: echo "command;exit"|script -q /dev/null
    std::string cd_path_and_command;
    if(path!="") {
      cd_path_and_command="cd \""+path+"\" && "+command;
    }
    else
      cd_path_and_command=command;
    execl("/bin/sh", "sh", "-c", cd_path_and_command.c_str(), NULL);
    perror("execl");
    exit(EXIT_FAILURE);
  }

  if(stdin_fd!=nullptr) close(stdin_p[0]);
  if(stdout_fd!=nullptr) close(stdout_p[1]);
  if(stderr_fd!=nullptr) close(stderr_p[1]);
  
  if(stdin_fd!=nullptr) *stdin_fd = stdin_p[1];
  if(stdout_fd!=nullptr) *stdout_fd = stdout_p[0];
  if(stderr_fd!=nullptr) *stderr_fd = stderr_p[0];

  return pid;
}

Terminal::InProgress::InProgress(const std::string& start_msg): stop(false) {
  waiting_print.connect([this](){
    Singleton::terminal()->async_print(line_nr-1, ".");
  });
  start(start_msg);
}

Terminal::InProgress::~InProgress() {
  stop=true;
  if(wait_thread.joinable())
    wait_thread.join();
}

void Terminal::InProgress::start(const std::string& msg) {
  line_nr=Singleton::terminal()->print(msg+"...\n");
  wait_thread=std::thread([this](){
    size_t c=0;
    while(!stop) {
      if(c%100==0)
        waiting_print();
      std::this_thread::sleep_for(std::chrono::milliseconds(10));
      c++;
    }
  });
}

void Terminal::InProgress::done(const std::string& msg) {
  if(!stop) {
    stop=true;
    Singleton::terminal()->async_print(line_nr-1, msg);
  }
}

void Terminal::InProgress::cancel(const std::string& msg) {
  if(!stop) {
    stop=true;
    Singleton::terminal()->async_print(line_nr-1, msg);
  }
}

Terminal::Terminal() {
  bold_tag=get_buffer()->create_tag();
  bold_tag->property_weight()=PANGO_WEIGHT_BOLD;
  
  async_print_dispatcher.connect([this](){
    async_print_strings_mutex.lock();
    if(async_print_strings.size()>0) {
      for(auto &string_bold: async_print_strings)
        print(string_bold.first, string_bold.second);
      async_print_strings.clear();
    }
    async_print_strings_mutex.unlock();
  });
  async_print_on_line_dispatcher.connect([this](){
    async_print_on_line_strings_mutex.lock();
    if(async_print_on_line_strings.size()>0) {
      for(auto &line_string: async_print_on_line_strings)
        print(line_string.first, line_string.second);
      async_print_on_line_strings.clear();
    }
    async_print_on_line_strings_mutex.unlock();
  });
}

int Terminal::execute(const std::string &command, const boost::filesystem::path &path, bool use_pipes) {
  int stdin_fd, stdout_fd, stderr_fd;
  pid_t pid;
  if(use_pipes)
    pid=popen3(command, path.string(), &stdin_fd, &stdout_fd, &stderr_fd);
  else
    pid=popen3(command, path.string(), nullptr, nullptr, nullptr);
  
  if (pid<=0) {
    async_print("Error: Failed to run command: " + command + "\n");
    return -1;
  }
  else {
    if(use_pipes) {
      std::thread stderr_thread([this, stderr_fd](){
        char buffer[buffer_size];
        ssize_t n;
        while ((n=read(stderr_fd, buffer, buffer_size)) > 0) {
          std::string message;
          message.reserve(n);
          for(ssize_t c=0;c<n;c++)
            message+=buffer[c];
          async_print(message, true);
        }
      });
      stderr_thread.detach();
      std::thread stdout_thread([this, stdout_fd](){
        char buffer[buffer_size];
        ssize_t n;
        while ((n=read(stdout_fd, buffer, buffer_size)) > 0) {
          std::string message;
          message.reserve(n);
          for(ssize_t c=0;c<n;c++)
            message+=buffer[c];
          async_print(message);
        }
      });
      stdout_thread.detach();
    }
    
    int exit_code;
    waitpid(pid, &exit_code, 0);
    if(use_pipes) {
      close(stdin_fd);
      close(stdout_fd);
      close(stderr_fd);
    }
    
    return exit_code;
  }
}

int Terminal::execute(std::istream &stdin_stream, std::ostream &stdout_stream, const std::string &command, const boost::filesystem::path &path) {
  int stdin_fd, stdout_fd, stderr_fd;
  auto pid=popen3(command, path.string(), &stdin_fd, &stdout_fd, &stderr_fd);
  
  if (pid<=0) {
    async_print("Error: Failed to run command: " + command + "\n");
    return -1;
  }
  else {
    std::thread stderr_thread([this, stderr_fd](){
      char buffer[buffer_size];
      ssize_t n;
      while ((n=read(stderr_fd, buffer, buffer_size)) > 0) {
        std::string message;
        message.reserve(n);
        for(ssize_t c=0;c<n;c++)
          message+=buffer[c];
        async_print(message, true);
      }
    });
    stderr_thread.detach();
    std::thread stdout_thread([this, &stdout_stream, stdout_fd](){
      char buffer[buffer_size];
      ssize_t n;
      while ((n=read(stdout_fd, buffer, buffer_size)) > 0) {
        Glib::ustring umessage;
        umessage.reserve(n);
        for(ssize_t c=0;c<n;c++)
          umessage+=buffer[c];
        Glib::ustring::iterator iter;
        while(!umessage.validate(iter)) {
          auto next_char_iter=iter;
          next_char_iter++;
          umessage.replace(iter, next_char_iter, "?");
        }
        stdout_stream.write(umessage.data(), n);
      }
    });
    stdout_thread.detach();
    
    char buffer[buffer_size];
    for(;;) {
      stdin_stream.readsome(buffer, buffer_size);
      auto read_n=stdin_stream.gcount();
      if(read_n==0)
        break;
      auto write_n=write(stdin_fd, buffer, read_n);
      if(write_n==0)
        break;
    }
    close(stdin_fd);
    
    int exit_code;
    waitpid(pid, &exit_code, 0);
    close(stdout_fd);
    close(stderr_fd);
    
    return exit_code;
  }
}

void Terminal::async_execute(const std::string &command, const boost::filesystem::path &path, std::function<void(int exit_code)> callback) {
  std::thread async_execute_thread([this, command, path, callback](){
    int stdin_fd, stdout_fd, stderr_fd;
    async_executes_mutex.lock();
    stdin_buffer.clear();
    auto pid=popen3(command, path.string(), &stdin_fd, &stdout_fd, &stderr_fd);
    async_executes.emplace_back(pid, stdin_fd);
    async_executes_mutex.unlock();
    
    if (pid<=0) {
      async_print("Error: Failed to run command: " + command + "\n");
      if(callback)
        callback(-1);
    }
    else {
      std::thread stderr_thread([this, stderr_fd](){
        char buffer[buffer_size];
        ssize_t n;
        while ((n=read(stderr_fd, buffer, buffer_size)) > 0) {
          std::string message;
          message.reserve(n);
          for(ssize_t c=0;c<n;c++)
            message+=buffer[c];
          async_print(message, true);
	}
      });
      stderr_thread.detach();
      std::thread stdout_thread([this, stdout_fd](){
        char buffer[buffer_size];
        ssize_t n;
        while ((n=read(stdout_fd, buffer, buffer_size)) > 0) {
          std::string message;
          message.reserve(n);
          for(ssize_t c=0;c<n;c++)
            message+=buffer[c];
          async_print(message);
	}
      });
      stdout_thread.detach();
      
      int exit_code;
      waitpid(pid, &exit_code, 0);
      async_executes_mutex.lock();
      for(auto it=async_executes.begin();it!=async_executes.end();it++) {
        if(it->first==pid) {
          async_executes.erase(it);
          break;
        }
      }
      stdin_buffer.clear();
      close(stdin_fd);
      close(stdout_fd);
      close(stderr_fd);
      async_executes_mutex.unlock();
      
      if(callback)
        callback(exit_code);
    }
  });
  async_execute_thread.detach();
}

void Terminal::kill_last_async_execute(bool force) {
  async_executes_mutex.lock();
  if(async_executes.size()>0) {
    if(force)
      kill(-async_executes.back().first, SIGTERM);
    else
      kill(-async_executes.back().first, SIGINT);
  }
  async_executes_mutex.unlock();
}

void Terminal::kill_async_executes(bool force) {
  async_executes_mutex.lock();
  for(auto &async_execute: async_executes) {
    if(force)
      kill(-async_execute.first, SIGTERM);
    else
      kill(-async_execute.first, SIGINT);
  }
  async_executes_mutex.unlock();
}

size_t Terminal::print(const std::string &message, bool bold){
  Glib::ustring umessage=message;
  Glib::ustring::iterator iter;
  while(!umessage.validate(iter)) {
    auto next_char_iter=iter;
    next_char_iter++;
    umessage.replace(iter, next_char_iter, "?");
  }
  
  if(bold)
    get_buffer()->insert_with_tag(get_buffer()->end(), umessage, bold_tag);
  else
    get_buffer()->insert(get_buffer()->end(), umessage);
  
  if(get_buffer()->get_line_count()>Singleton::Config::terminal()->history_size) {
    int lines=get_buffer()->get_line_count()-Singleton::Config::terminal()->history_size;
    get_buffer()->erase(get_buffer()->begin(), get_buffer()->get_iter_at_line(lines));
    deleted_lines+=static_cast<size_t>(lines);
  }
  
  return static_cast<size_t>(get_buffer()->end().get_line())+deleted_lines;
}

void Terminal::print(size_t line_nr, const std::string &message){
  if(line_nr<deleted_lines)
    return;
  
  Glib::ustring umessage=message;
  Glib::ustring::iterator iter;
  while(!umessage.validate(iter)) {
    auto next_char_iter=iter;
    next_char_iter++;
    umessage.replace(iter, next_char_iter, "?");
  }
  
  auto end_line_iter=get_buffer()->get_iter_at_line(static_cast<int>(line_nr-deleted_lines));
  while(!end_line_iter.ends_line() && end_line_iter.forward_char()) {}
  get_buffer()->insert(end_line_iter, umessage);
}

std::shared_ptr<Terminal::InProgress> Terminal::print_in_progress(std::string start_msg) {
  std::shared_ptr<Terminal::InProgress> in_progress=std::shared_ptr<Terminal::InProgress>(new Terminal::InProgress(start_msg));
  return in_progress;
}

void Terminal::async_print(const std::string &message, bool bold) {
  async_print_strings_mutex.lock();
  bool dispatch=true;
  if(async_print_strings.size()>0)
    dispatch=false;
  async_print_strings.emplace_back(message, bold);
  async_print_strings_mutex.unlock();
  if(dispatch)
    async_print_dispatcher();
}

void Terminal::async_print(int line_nr, const std::string &message) {
  async_print_on_line_strings_mutex.lock();
  bool dispatch=true;
  if(async_print_on_line_strings.size()>0)
    dispatch=false;
  async_print_on_line_strings.emplace_back(line_nr, message);
  async_print_on_line_strings_mutex.unlock();
  if(dispatch)
    async_print_on_line_dispatcher();
}

bool Terminal::on_key_press_event(GdkEventKey *event) {
  async_executes_mutex.lock();
  if(async_executes.size()>0) {
    get_buffer()->place_cursor(get_buffer()->end());
    auto unicode=gdk_keyval_to_unicode(event->keyval);
    char chr=(char)unicode;
    if(unicode>=32 && unicode<=126) {
      stdin_buffer+=chr;
      get_buffer()->insert_at_cursor(stdin_buffer.substr(stdin_buffer.size()-1));
    }
    else if(event->keyval==GDK_KEY_BackSpace) {
      if(stdin_buffer.size()>0 && get_buffer()->get_char_count()>0) {
        auto iter=get_buffer()->end();
        iter--;
        stdin_buffer.pop_back();
        get_buffer()->erase(iter, get_buffer()->end());
      }
    }
    else if(event->keyval==GDK_KEY_Return) {
      stdin_buffer+='\n';
      write(async_executes.back().second, stdin_buffer.c_str(), stdin_buffer.size());
      get_buffer()->insert_at_cursor(stdin_buffer.substr(stdin_buffer.size()-1));
      stdin_buffer.clear();
    }
  }
  async_executes_mutex.unlock();
  return true;
}