/*

 * histolog.c     -- File history handling

 *

 * Copyright (C) 2005 Mikael Berthe <bmikael@lists.lilotux.net>

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License as published by

 * the Free Software Foundation; either version 2 of the License, or (at

 * your option) any later version.

 *

 * This program is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307

 * USA

 */

#include <string.h>

#include <stdlib.h>

#include <time.h>

#include <ctype.h>

#include <sys/types.h>

#include <sys/stat.h>

#include <fcntl.h>

#include "histolog.h"

#include "hbuf.h"

#include "jabglue.h"

#include "utils.h"

#include "logprint.h"

static guint UseFileLogging;

static guint FileLoadLogs;

static char *RootDir;

//  user_histo_file()

// Returns history filename for the given jid

// Note: the caller *must* free the filename after use (if not null).

static char *user_histo_file(const char *jid)

{

  char *filename;

  char *lowerid, *p;

  if (!UseFileLogging && !FileLoadLogs) return NULL;

  lowerid = g_strdup(jid);

  for (p=lowerid; *p ; p++)

    *p = tolower(*p);

  filename = g_new(char, strlen(RootDir) + strlen(jid) + 1);

  strcpy(filename, RootDir);

  strcat(filename, lowerid);

  g_free(lowerid);

  return filename;

}

//  write_histo_line()

// Adds a history (multi-)line to the jid's history logfile

static void write_histo_line(const char *jid,

        time_t timestamp, guchar type, guchar info, const char *data)

{

  guint len = 0;

  FILE *fp;

  time_t ts;

  const char *p;

  char *filename;

  char str_ts[20];

  int err;

  if (!UseFileLogging) return;

  filename = user_histo_file(jid);

  // If timestamp is null, get current date

  if (timestamp)

    ts = timestamp;

  else

    time(&ts);

  if (!data)

    data = "";

  // Count number of extra lines

  for (p=data ; *p ; p++)

    if (*p == '\n') len++;

  /* Line format: "TI yyyymmddThh:mm:ssZ [data]"

   * (Old format: "TI DDDDDDDDDD LLL [data])"

   * T=Type, I=Info, yyyymmddThh:mm:ssZ=date, LLL=0-padded-len

   *

   * Types:

   * - M message    Info: S (send) R (receive)

   * - S status     Info: [_oifdna]

   * We don't check them, we'll trust the caller.

   */

  fp = fopen(filename, "a");

  g_free(filename);

  if (!fp) {

    scr_LogPrint(LPRINT_LOGNORM, "Unable to write history "

                 "(cannot open logfile)");

    return;

  }

  to_iso8601(str_ts, ts);

  err = fprintf(fp, "%c%c %-18.18s %03d %s\n", type, info, str_ts, len, data);

  fclose(fp);

  if (err < 0) {

    scr_LogPrint(LPRINT_LOGNORM, "Error while writing to log file: %s",

                 strerror(errno));

  }

}

//  hlog_read_history()

// Reads the jid's history logfile

void hlog_read_history(const char *jid, GList **p_buddyhbuf, guint width)

{

  char *filename;

  guchar type, info;

  char *data, *tail;

  time_t timestamp;

  guint prefix_flags;

  guint len;

  FILE *fp;

  struct stat bufstat;

  guint err = 0;

  guint ln = 0; // line number

  if (!FileLoadLogs) return;

  data = g_new(char, HBB_BLOCKSIZE+32);

  if (!data) {

    scr_LogPrint(LPRINT_LOGNORM, "Not enough memory to read history file");

    return;

  }

  filename = user_histo_file(jid);

  fp = fopen(filename, "r");

  g_free(filename);

  if (!fp) { g_free(data); return; }

  // If file is large (> 3MB here), display a message to inform the user

  // (it can take a while...)

  if (!fstat(fileno(fp), &bufstat)) {

    if (bufstat.st_size > 3145728)

      scr_LogPrint(LPRINT_LOGNORM, "Reading <%s> history file...", jid);

  }

  /* See write_histo_line() for line format... */

  while (!feof(fp)) {

    if (fgets(data, HBB_BLOCKSIZE+27, fp) == NULL) break;

    ln++;

    for (tail = data; *tail; tail++) ;

    type = data[0];

    info = data[1];

    if ((type != 'M' && type != 'S') ||

        ((data[11] != 'T') || (data[20] != 'Z') ||

         (data[21] != ' ') || (data[25] != ' '))) {

      if (!err) {

        scr_LogPrint(LPRINT_LOGNORM, "Error in history file format (%s), l.%u",

                     jid, ln);

        err = 1;

      }

      //break;

      continue;

    }

    data[21] = data[25] = 0;

    timestamp = from_iso8601(&data[3], 1);

    len = (guint) atoi(&data[22]);

    // Some checks

    if (((type == 'M') && (info != 'S' && info != 'R')) ||

        ((type == 'I') && (!strchr("OAIFDN", info)))) {

      if (!err) {

        scr_LogPrint(LPRINT_LOGNORM, "Error in history file format (%s), l.%u",

                     jid, ln);

        err = 1;

      }

      //break;

      continue;

    }

    // XXX This will fail when a message is too big

    while (len--) {

      ln++;

      if (fgets(tail, HBB_BLOCKSIZE+27 - (tail-data), fp) == NULL)

        break;

      while (*tail) tail++;

    }

    // Small check for too long messages

    if (tail >= HBB_BLOCKSIZE+26 + data) {

      // Maybe we will have a parse error on next, because this

      // message is big (maybe too big).

      scr_LogPrint(LPRINT_LOGNORM, "A message could be too big "

                   "in history file...");

    }

    // Remove last CR (we keep it if the line is empty, too)

    if ((tail > data+26) && (*(tail-1) == '\n'))

      *(tail-1) = 0;

    if (type == 'M') {

      if (info == 'S')

        prefix_flags = HBB_PREFIX_OUT;

      else

        prefix_flags = HBB_PREFIX_IN;

      hbuf_add_line(p_buddyhbuf, &data[26], timestamp,

                    prefix_flags, width);

      err = 0;

    }

  }

  fclose(fp);

  g_free(data);

}

//  hlog_enable()

// Enable logging to files.  If root_dir is NULL, then $HOME/.mcabber is used.

// If loadfiles is TRUE, we will try to load buddies history logs from file.

void hlog_enable(guint enable, const char *root_dir, guint loadfiles)

{

  UseFileLogging = enable;

  FileLoadLogs = loadfiles;

  if (enable || loadfiles) {

    if (root_dir) {

      int l = strlen(root_dir);

      if (l < 1) {

        scr_LogPrint(LPRINT_LOGNORM, "Error: logging dir name too short");

        UseFileLogging = FileLoadLogs = FALSE;

        return;

      }

      // RootDir must be slash-terminated

      if (root_dir[l-1] == '/')

        RootDir = g_strdup(root_dir);

      else {

        RootDir = g_new(char, l+2);

        strcpy(RootDir, root_dir);

        strcat(RootDir, "/");

      }

    } else {

      char *home = getenv("HOME");

      char *dir = "/.mcabber/histo/";

      RootDir = g_new(char, strlen(home) + strlen(dir) + 1);

      strcpy(RootDir, home);

      strcat(RootDir, dir);

    }

    // Check directory permissions (should not be readable by group/others)

    if (checkset_perm(RootDir, TRUE) == -1) {

      // The directory does not actually exists

      g_free(RootDir);

      scr_LogPrint(LPRINT_LOGNORM, "ERROR: Cannot access "

                   "history log directory, logging DISABLED");

      UseFileLogging = FileLoadLogs = FALSE;

    }

  } else {  // Disable history logging

    if (RootDir)

      g_free(RootDir);

  }

}

inline void hlog_write_message(const char *jid, time_t timestamp, int sent,

        const char *msg)

{

  write_histo_line(jid, timestamp, 'M', ((sent) ? 'S' : 'R'), msg);

}

inline void hlog_write_status(const char *jid, time_t timestamp,

        enum imstatus status, const char *status_msg)

{

  // #1 XXX Check status value?

  // #2 We could add a user-readable comment

  write_histo_line(jid, timestamp, 'S', toupper(imstatus2char[status]),

          status_msg);

}