#define _GNU_SOURCE 
#include <readline/readline.h>
#include <readline/history.h>

#include <assert.h>
#include <stdio.h>

#include <stdlib.h>
#include <string.h>
#include "include.h"
char *default_prompt = ">";

char *get_default_prompt (void) {
  return default_prompt;
}

char *complete_none (const char *text UU, int state UU) {
  return 0;
}

char *commands[] = {
  "help",
  "msg",
  0 };

int commands_flags[] = {
  070,
  072,
};

char *a = 0;
char **user_list = &a;
char **chat_list = &a;

int init_token (char **q) {
  char *r = *q;
  while (*r == ' ') { r ++; }
  if (!*r) { return 0; }
  *q = r;
  return 1;
}

char *get_token (char **q, int *l) {
  char *r = *q;
  while (*r == ' ') { r ++; }
  if (!*r) { 
    *q = r; 
    *l = 0;
    return 0;
  }
  int neg = 0;
  char *s = r;
  while (*r && (*r != ' ' || neg)) {
    if (*r == '\\') {
      neg = 1 - neg;
    } else {
      neg = 0;
    }
    r++;
  }
  *q = r;
  *l = r - s;
  return s;
}


int get_complete_mode (void) {
  char *q = rl_line_buffer;
  if (!init_token (&q)) { return 0; }
  int l = 0;
  char *r = get_token (&q, &l);
  if (!*q) { return 0; }
  
  char **command = commands;
  int n = 0;
  int flags = -1;
  while (*command) {
    if (!strncmp (r, *command, l)) {
      flags = commands_flags[n];
      break;
    }
    n ++;
    command ++;
  }
  if (flags == -1) {
    return -1;
  }
  int s = 0;
  while (1) {
    get_token (&q, &l);
    if (!*q) { return flags & 7; }
    s ++;
    if (s <= 4) { flags >>= 3; }
  }
}

int complete_string_list (char **list, int index, const char *text, int len, char **R) {
  index ++;
  while (list[index] && strncmp (list[index], text, len)) {
    index ++;
  }
  if (list[index]) {
    *R = strdup (list[index]);
    return index;
  } else {
    *R = 0;
    return -1;
  }
}
char *command_generator (const char *text, int state) {  
  static int len, index, mode;
 
  if (!state) {
    len = strlen (text);
    index = -1;
     
    rl_line_buffer[rl_point] = '\0'; /* the effect should be such
			* that the cursor position
			* is at the end of line for
		  * the auto completion regex
			* above (note the $ at end)
			*/

    mode = get_complete_mode ();
  } else {
    if (index == -1) { return 0; }
  }

  if (mode == -1) { return 0; }

  char *R = 0;
  switch (mode & 7) {
  case 0:
    index = complete_string_list (commands, index, text, len, &R);
    return R;
  case 1:
    index = complete_string_list (user_list, index, text, len, &R);
    return R;
  case 2:
    index = complete_string_list (chat_list, index, text, len, &R);
    return R;
  case 3:
    return rl_filename_completion_function(text,state);
  default:
    return 0;
  }
}

char **complete_text (char *text, int start UU, int end UU) {
  return (char **) rl_completion_matches (text, command_generator);
}

void interpreter (char *line UU) {
  assert (0);
}