/**********************************************************************
 *
 *  G_read_history (name, mapset, phist)
 *      char *name                   name of map
 *      char *mapset                 mapset that map belongs to
 *      struct History *phist        structure to hold history info
 *
 *  Reads the history information associated with map layer "map"
 *  in mapset "mapset" into the structure "phist".
 *
 *   returns:    0  if successful
 *              -1  on fail
 *
 *  note:   a warning message is printed if the file is incorrect
 *
 **********************************************************************
 *
 *  G_write_history (name, phist)
 *      char *name                   name of map
 *      struct History *phist        structure holding history info
 *
 *  Writes the history information associated with map layer "map"
 *  into current from the structure "phist".
 *
 *   returns:    0  if successful
 *              -1  on fail
 ***********************************************************************
 *
 *  G_short_history (name, type, hist)
 *     char *name             name of cell file
 *     char *type             type of cell file
 *     struct History *hist   History structure to be filled in
 *
 *  Puts local information like time and date, user's name, map name,
 *  and current mapset name into the hist structure
 *
 *  NOTE: use G_write_history() to write the structure.
 **********************************************************************
 *
 *  G_command_history (hist)
 *     struct History *hist   History structure to be filled in
 *
 *  Appends (parsed) command line to history structure's comments
 *
 * Returns:
 *     0 success
 *     1 failure (history file full, no change)
 *     2 failure (history file full, added as much as we could)
 *
 *  NOTE: initialize structure with G_short_history() first.
 *  NOTE: use G_write_history() to write the structure.
 **********************************************************************/

#include <string.h>
#include <grass/gis.h>
#include <grass/glocale.h>


/*!
 * \brief read raster history file
 *
 * This routine reads the history file for
 * the raster map <b>name</b> in <b>mapset</b> into the <b>history</b>
 * structure.
 * A diagnostic message is printed and -1 is returned if there is an error
 * reading the history file. Otherwise, 0 is returned.
 *
 *  \param name
 *  \param mapset
 *  \param history
 *  \return int
 */

int G_read_history(const char *name, const char *mapset, struct History *hist)
{
    FILE *fd;

    G_zero(hist, sizeof(struct History));
    fd = G_fopen_old("hist", name, mapset);
    if (!fd)
	goto error;


    if (!G_getl(hist->mapid, sizeof(hist->mapid), fd))
	goto error;
    G_ascii_check(hist->mapid);

    if (!G_getl(hist->title, sizeof(hist->title), fd))
	goto error;
    G_ascii_check(hist->title);

    if (!G_getl(hist->mapset, sizeof(hist->mapset), fd))
	goto error;
    G_ascii_check(hist->mapset);

    if (!G_getl(hist->creator, sizeof(hist->creator), fd))
	goto error;
    G_ascii_check(hist->creator);

    if (!G_getl(hist->maptype, sizeof(hist->maptype), fd))
	goto error;
    G_ascii_check(hist->maptype);

    if (!G_getl(hist->datsrc_1, sizeof(hist->datsrc_1), fd))
	goto error;
    G_ascii_check(hist->datsrc_1);

    if (!G_getl(hist->datsrc_2, sizeof(hist->datsrc_2), fd))
	goto error;
    G_ascii_check(hist->datsrc_2);

    if (!G_getl(hist->keywrd, sizeof(hist->keywrd), fd))
	goto error;
    G_ascii_check(hist->keywrd);

    hist->edlinecnt = 0;
    while ((hist->edlinecnt < MAXEDLINES) &&
	   (G_getl
	    (hist->edhist[hist->edlinecnt], sizeof(hist->edhist[0]), fd))) {
	G_ascii_check(hist->edhist[hist->edlinecnt]);
	hist->edlinecnt++;
    }


    fclose(fd);
    return 0;

  error:
    if (fd != NULL)
	fclose(fd);
    G_warning(_("can't get history information for [%s] in mapset [%s]"),
	      name, mapset);
    return -1;
}


/*!
 * \brief write raster history file
 *
 * This routine writes the history file for the raster map
 * <b>name</b> in the current mapset from the <b>history</b> structure.
 * A diagnostic message is printed and -1 is returned if there is an error
 * writing the history file. Otherwise, 0 is returned.
 * <b>Note.</b> The <b>history</b> structure should first be initialized
 * using <i>G_short_history.</i>
 *
 *  \param name
 *  \param history
 *  \return int
 */

int G_write_history(const char *name, struct History *hist)
{
    FILE *fd;
    int i;

    fd = G_fopen_new("hist", name);
    if (!fd)
	goto error;

    fprintf(fd, "%s\n", hist->mapid);
    fprintf(fd, "%s\n", hist->title);
    fprintf(fd, "%s\n", hist->mapset);
    fprintf(fd, "%s\n", hist->creator);
    fprintf(fd, "%s\n", hist->maptype);
    fprintf(fd, "%s\n", hist->datsrc_1);
    fprintf(fd, "%s\n", hist->datsrc_2);
    fprintf(fd, "%s\n", hist->keywrd);

    for (i = 0; i < hist->edlinecnt; i++)
	fprintf(fd, "%s\n", hist->edhist[i]);

    fclose(fd);
    return 0;

  error:
    if (fd)
	fclose(fd);
    G_warning(_("can't write history information for [%s]"), name);
    return -1;
}



/*!
 * \brief initialize history structure
 *
 * This routine initializes the
 * <b>history</b> structure, recording the date, user, module name and the
 * raster map <b>name</b> structure. The <b>type</b> is an anachronism from
 * earlier versions of GRASS and should be specified as "raster".
 * <b>Note.</b> This routine only initializes the data structure. It does not
 * write the history file.
 *
 *  \param name
 *  \param type
 *  \param history
 *  \return int
 */

int G_short_history(const char *name, const char *type, struct History *hist)
{
    strncpy(hist->mapid, G_date(), RECORD_LEN);
    strncpy(hist->title, name, RECORD_LEN);
    strncpy(hist->mapset, G_mapset(), RECORD_LEN);
    strncpy(hist->creator, G_whoami(), RECORD_LEN);
    strncpy(hist->maptype, type, RECORD_LEN);

    sprintf(hist->keywrd, "generated by %s", G_program_name());
    strcpy(hist->datsrc_1, "");
    strcpy(hist->datsrc_2, "");
    hist->edlinecnt = 0;

    return 1;
}

/*!
 * \brief Save command line to raster history structure
 *
 * This routine takes an existing (run <i>G_short_history first</i>) history
 *  structure and adds the command line to the end of the comments array, as
 *  cleaned & expanded by the parser.
 *
 * History file is limited to [80]x[50], as defined in include/gis.h
 *
 * * First version had for loops of [i][j] character assignments and ending
 *   nulls, but using the string libraries is cleaner and less bug prone.
 * * Second version had white space detection, intelligent wrapping, and
 *   indentation of continued lines, but this proved a pain in the neck for 
 *   things like r.patch which can have long strings without any
 *   parser-acceptable breaks.
 * * This is MK-III, simplified, but that's good: it's cut & paste-able.
 *
 *  NOTE: use G_write_history() to write the structure.
 *
 * Sample Usage:
 *
 *   struct History history;
 *   G_short_history(rasterfile, "raster", &history);
 *   G_command_history(&history);
 *   G_write_history(rasterfile, &history);
 *
 * Returns:
 *     0 success
 *     1 failure (history file full, no change)
 *     2 failure (history file full, added as much as we could)
 *
 * \param history
 * \return int
 *
 */

int G_command_history(struct History *hist)
{
    int j, cmdlen;
    char *cmdlin;

    cmdlin = G_recreate_command();
    cmdlen = strlen(cmdlin);

    if (hist->edlinecnt > MAXEDLINES - 2) {
	G_warning(_("Not enough room in history file to record command line."));
	return 1;
    }

    if (hist->edlinecnt > 0) {	/* add a blank line if preceding history exists */
	strcpy(hist->edhist[hist->edlinecnt], "");
	hist->edlinecnt++;
    }

    if (cmdlen < 70) {		/* ie if it will fit on a single line */
	sprintf(hist->edhist[hist->edlinecnt], G_recreate_command());
	hist->edlinecnt++;
    }
    else {			/* multi-line required */
	j = 0;			/* j is the current position in the command line string */
	while ((cmdlen - j) > 70) {
	    strncpy(hist->edhist[hist->edlinecnt], &cmdlin[j], 68);
	    hist->edhist[hist->edlinecnt][68] = '\0';
	    strcat(hist->edhist[hist->edlinecnt], "\\");
	    j += 68;
	    hist->edlinecnt++;
	    if (hist->edlinecnt > MAXEDLINES - 2) {
		G_warning(_("Not enough room in history file for command line (truncated)."));
		return 2;
	    }
	}
	if ((cmdlen - j) > 0) {	/* ie anything left */
	    strcpy(hist->edhist[hist->edlinecnt], &cmdlin[j]);
	    hist->edlinecnt++;
	}
    }
    return 0;
}