/* -*- Mode: C -*-
    ======================================================================
    FILE: icaldirset.c
    CREATOR: eric 28 November 1999
  
    $Id: icaldirset.c,v 1.24 2008-01-02 20:07:40 dothebart Exp $
    $Locker:  $
    
 (C) COPYRIGHT 2000, Eric Busboom, http://www.softwarestudio.org

 This program is free software; you can redistribute it and/or modify
 it under the terms of either: 

    The LGPL as published by the Free Software Foundation, version
    2.1, available at: http://www.fsf.org/copyleft/lesser.html

  Or:

    The Mozilla Public License Version 1.0. You may obtain a copy of
    the License at http://www.mozilla.org/MPL/

    The Original Code is eric. The Initial Developer of the Original
    Code is Eric Busboom


    ======================================================================*/


/**
   @file   icaldirset.c
 
   @brief  icaldirset manages a database of ical components and offers
  interfaces for reading, writing and searching for components.

  icaldirset groups components in to clusters based on their DTSTAMP
  time -- all components that start in the same month are grouped
  together in a single file. All files in a sotre are kept in a single
  directory. 

  The primary interfaces are icaldirset__get_first_component and
  icaldirset_get_next_component. These routine iterate through all of
  the components in the store, subject to the current gauge. A gauge
  is an icalcomponent that is tested against other componets for a
  match. If a gauge has been set with icaldirset_select,
  icaldirset_first and icaldirset_next will only return componentes
  that match the gauge.

  The Store generated UIDs for all objects that are stored if they do
  not already have a UID. The UID is the name of the cluster (month &
  year as MMYYYY) plus a unique serial number. The serial number is
  stored as a property of the cluster.

*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif


#include <libical/ical.h>
#include "icaldirset.h"
#include "icaldirset.h"
#include "icalfileset.h"
#include "icalfilesetimpl.h"
#include "icalcluster.h"
#include "icalgauge.h"

#ifndef WIN32
#include <dirent.h> /* for opendir() */
#include <unistd.h> /* for stat, getpid */
#include <sys/utsname.h> /* for uname */
#else
#include <io.h>
#include <process.h>
#endif

#include <errno.h>
#include <sys/types.h> /* for opendir() */
#include <sys/stat.h> /* for stat */
#include <limits.h> /* For PATH_MAX */
#include <time.h> /* for clock() */
#include <stdlib.h> /* for rand(), srand() */
#include <string.h> /* for strdup */
#include "icaldirsetimpl.h"

#if defined(_MSC_VER)
#define _S_ISTYPE(mode, mask)  (((mode) & _S_IFMT) == (mask))
#define S_ISDIR(mode)    _S_ISTYPE((mode), _S_IFDIR)
#define S_ISREG(mode)    _S_ISTYPE((mode), _S_IFREG)
#define snprintf _snprintf
#define strcasecmp stricmp
#endif

/** Default options used when NULL is passed to icalset_new() **/
icaldirset_options icaldirset_options_default = {O_RDWR|O_CREAT};


const char* icaldirset_path(icalset* set)
{
  icaldirset *dset = (icaldirset*)set;

  return dset->dir;
}


void icaldirset_mark(icalset* set)
{
  icaldirset *dset = (icaldirset*)set;

  icalcluster_mark(dset->cluster);
}


icalerrorenum icaldirset_commit(icalset* set)
{
  icaldirset *dset = (icaldirset*)set;
  icalset *fileset;
  icalfileset_options options = icalfileset_options_default;

  options.cluster = dset->cluster;

  fileset = icalset_new(ICAL_FILE_SET, icalcluster_key(dset->cluster), &options);

  fileset->commit(fileset);
  fileset->free(fileset);

  return ICAL_NO_ERROR;
}

void icaldirset_lock(const char* dir)
{
}


void icaldirset_unlock(const char* dir)
{
}

/* Load the contents of the store directory into the store's internal directory list*/
icalerrorenum icaldirset_read_directory(icaldirset *dset)
{
    char *str;
#ifndef WIN32
    struct dirent *de;
    DIR* dp;
 
    dp = opendir(dset->dir);
   
    if (dp == 0) {
	icalerror_set_errno(ICAL_FILE_ERROR);
	return ICAL_FILE_ERROR;
    }

    /* clear contents of directory list */
    while((str = pvl_pop(dset->directory))){
	free(str);
    }
    
    /* load all of the cluster names in the directory list */
    for(de = readdir(dp);
	de != 0;
	de = readdir(dp)){

	/* Remove known directory names  '.' and '..'*/
	if (strcmp(de->d_name,".") == 0 ||
	    strcmp(de->d_name,"..") == 0 ){
	    continue;
	}

	pvl_push(dset->directory, (void*)strdup(de->d_name));	
    }

    closedir(dp);
#else
    struct _finddata_t c_file;
    intptr_t hFile;
	
    /* Find first .c file in current directory */
    if( (hFile = _findfirst( "*", &c_file )) == -1L ) {
		icalerror_set_errno(ICAL_FILE_ERROR);
		return ICAL_FILE_ERROR;
    } else {
      while((str = pvl_pop(dset->directory))){
			free(str);
		}
		
		/* load all of the cluster names in the directory list */
      do {
			/* Remove known directory names  '.' and '..'*/
			if (strcmp(c_file.name,".") == 0 ||
				strcmp(c_file.name,"..") == 0 ){
				continue;
			}
			
	pvl_push(dset->directory, (void*)strdup(c_file.name));
		}
		while ( _findnext( hFile, &c_file ) == 0 );
			
		_findclose( hFile );
	}

#endif

    return ICAL_NO_ERROR;
}


icalset* icaldirset_init(icalset* set, const char* dir, void* options_in)
{
  icaldirset *dset = (icaldirset*)set;
  icaldirset_options *options = options_in;
    struct stat sbuf;

    icalerror_check_arg_rz( (dir!=0), "dir");
  icalerror_check_arg_rz( (set!=0), "set");

    if (stat(dir,&sbuf) != 0){
	icalerror_set_errno(ICAL_FILE_ERROR);
	return 0;
    }
    
    /* dir is not the name of a direectory*/
    if (!S_ISDIR(sbuf.st_mode)){ 
	icalerror_set_errno(ICAL_USAGE_ERROR);
	return 0;
    }	    

    icaldirset_lock(dir);

  dset->dir = (char*)strdup(dir);
  dset->options = *options;
  dset->directory = pvl_newlist();
  dset->directory_iterator = 0;
  dset->gauge = 0;
  dset->first_component = 0;
  dset->cluster = 0;

  return set;
}

icalset* icaldirset_new(const char* dir)
{
  return icalset_new(ICAL_DIR_SET, dir, &icaldirset_options_default);
}

    
icalset* icaldirset_new_reader(const char* dir)
{
  icaldirset_options reader_options = icaldirset_options_default;

  reader_options.flags = O_RDONLY;

  return icalset_new(ICAL_DIR_SET, dir, &reader_options);
}

    
icalset* icaldirset_new_writer(const char* dir)
{
  icaldirset_options writer_options = icaldirset_options_default;

  writer_options.flags = O_RDWR|O_CREAT;

  return icalset_new(ICAL_DIR_SET, dir, &writer_options);
}


void icaldirset_free(icalset* s)
{
  icaldirset *dset = (icaldirset*)s;
    char* str;

  icaldirset_unlock(dset->dir);

  if(dset->dir !=0){
    free(dset->dir);
    dset->dir = 0;
    }

  if(dset->gauge !=0){
    icalgauge_free(dset->gauge);
    dset->gauge = 0;
    }

  if(dset->cluster !=0){
    icalcluster_free(dset->cluster);
    }

  while(dset->directory !=0 &&  (str=pvl_pop(dset->directory)) != 0){
	free(str);
    }

  if(dset->directory != 0){
    pvl_free(dset->directory);
    dset->directory = 0;
    }

  dset->directory_iterator = 0;
  dset->first_component = 0;
}


/* icaldirset_next_uid_number updates a serial number in the Store
   directory in a file called SEQUENCE */

int icaldirset_next_uid_number(icaldirset* dset)
{
    char sequence = 0;
    char temp[128];
    char filename[ICAL_PATH_MAX];
    char *r;
    FILE *f;
    struct stat sbuf;

    icalerror_check_arg_rz( (dset!=0), "dset");

    snprintf(filename,sizeof(filename),"%s/%s",dset->dir,"SEQUENCE");

    /* Create the file if it does not exist.*/
    if (stat(filename,&sbuf) == -1 || !S_ISREG(sbuf.st_mode)){

	f = fopen(filename,"w");
	if (f != 0){
	    fprintf(f,"0");
	    fclose(f);
	} else {
	    icalerror_warn("Can't create SEQUENCE file in icaldirset_next_uid_number");
	    return 0;
	}
    }
    
    if ( (f = fopen(filename,"r+")) != 0){

	rewind(f);
	r = fgets(temp,128,f);

	if (r == 0){
	    sequence = 1;
	} else {
	    sequence = atoi(temp)+1;
	}

	rewind(f);

	fprintf(f,"%d",sequence);

	fclose(f);

	return sequence;
	
    } else {
	icalerror_warn("Can't create SEQUENCE file in icaldirset_next_uid_number");
	return 0;
    }
}

icalerrorenum icaldirset_next_cluster(icaldirset* dset)
{
    char path[ICAL_PATH_MAX];

    if (dset->directory_iterator == 0){
	icalerror_set_errno(ICAL_INTERNAL_ERROR);
	return ICAL_INTERNAL_ERROR;
    }	    
    dset->directory_iterator = pvl_next(dset->directory_iterator);

    if (dset->directory_iterator == 0){
	/* There are no more clusters */
	if(dset->cluster != 0){
	    icalcluster_free(dset->cluster);
	    dset->cluster = 0;
	}
	return ICAL_NO_ERROR;
    }
	    
    snprintf(path,sizeof(path),"%s/%s", dset->dir,(char*)pvl_data(dset->directory_iterator));

    icalcluster_free(dset->cluster);
    dset->cluster = icalfileset_produce_icalcluster(path);

    return icalerrno;
}

static void icaldirset_add_uid(icalcomponent* comp)
{
    char uidstring[ICAL_PATH_MAX];
    icalproperty *uid;
#ifndef WIN32
    struct utsname unamebuf;
#endif

    icalerror_check_arg_rv( (comp!=0), "comp");

    uid = icalcomponent_get_first_property(comp,ICAL_UID_PROPERTY);
    
    if (uid == 0) {
	
#ifndef WIN32
	uname(&unamebuf);
	
	snprintf(uidstring,sizeof(uidstring),"%d-%s",(int)getpid(),unamebuf.nodename);
#else
	snprintf(uidstring,sizeof(uidstring),"%d-%s",(int)getpid(),"WINDOWS");  /* FIX: There must be an easy get the system name */
#endif
	
	uid = icalproperty_new_uid(uidstring);
	icalcomponent_add_property(comp,uid);
    } else {
	strncpy(uidstring,icalproperty_get_uid(uid),ICAL_PATH_MAX-1);
	uidstring[ICAL_PATH_MAX-1]='\0';
    }
}


/**
  This assumes that the top level component is a VCALENDAR, and there
   is an inner component of type VEVENT, VTODO or VJOURNAL. The inner
  component must have a DSTAMP property 
*/

icalerrorenum icaldirset_add_component(icalset* set, icalcomponent* comp)
{
    char clustername[ICAL_PATH_MAX];
    icalproperty *dt = 0;
    icalvalue *v;
    struct icaltimetype tm;
    icalerrorenum error = ICAL_NO_ERROR;
    icalcomponent *inner;
    icaldirset *dset = (icaldirset*) set;

    icalerror_check_arg_rz( (dset!=0), "dset");
    icalerror_check_arg_rz( (comp!=0), "comp");

    icaldirset_add_uid(comp);

    /* Determine which cluster this object belongs in. This is a HACK */

    for(inner = icalcomponent_get_first_component(comp,ICAL_ANY_COMPONENT);
	inner != 0;
	inner = icalcomponent_get_next_component(comp,ICAL_ANY_COMPONENT)){
  
	dt = icalcomponent_get_first_property(inner,ICAL_DTSTAMP_PROPERTY);
 	
      if (dt != 0)
	    break; 
	}	

    if (dt == 0) {
	for(inner = icalcomponent_get_first_component(comp,ICAL_ANY_COMPONENT);
	    inner != 0;
	    inner = icalcomponent_get_next_component(comp,ICAL_ANY_COMPONENT)){
	    
	    dt = icalcomponent_get_first_property(inner,ICAL_DTSTART_PROPERTY);
	    
	  if (dt != 0)
		break; 
	    }	
	}

    if (dt == 0){
	icalerror_warn("The component does not have a DTSTAMP or DTSTART property, so it cannot be added to the store");
	icalerror_set_errno(ICAL_BADARG_ERROR);
	return ICAL_BADARG_ERROR;
    }

    v = icalproperty_get_value(dt);
    tm = icalvalue_get_datetime(v);

    snprintf(clustername,ICAL_PATH_MAX,"%s/%04d%02d",dset->dir, tm.year, tm.month);

    /* Load the cluster and insert the object */
    if(dset->cluster != 0 && 
       strcmp(clustername,icalcluster_key(dset->cluster)) != 0 ){
      icalcluster_free(dset->cluster);
      dset->cluster = 0;
    }

    if (dset->cluster == 0){
      dset->cluster = icalfileset_produce_icalcluster(clustername);

      if (dset->cluster == 0){
	    error = icalerrno;
	}
    }
    
    if (error != ICAL_NO_ERROR){
	icalerror_set_errno(error);
	return error;
    }

    /* Add the component to the cluster */
    icalcluster_add_component(dset->cluster,comp);
    
    /* icalcluster_mark(impl->cluster); */

    return ICAL_NO_ERROR;    
}

/**
   Remove a component in the current cluster. HACK. This routine is a
   "friend" of icalfileset, and breaks its encapsulation. It was
   either do it this way, or add several layers of interfaces that had
   no other use.  
 */

icalerrorenum icaldirset_remove_component(icalset* set, icalcomponent* comp)
{
    icaldirset *dset = (icaldirset*)set;
    icalcomponent *filecomp = icalcluster_get_component(dset->cluster);

    icalcompiter i;
    int found = 0;

    icalerror_check_arg_re((set!=0),"set",ICAL_BADARG_ERROR);
    icalerror_check_arg_re((comp!=0),"comp",ICAL_BADARG_ERROR);
    icalerror_check_arg_re((dset->cluster!=0),"Cluster pointer",ICAL_USAGE_ERROR);

    for(i = icalcomponent_begin_component(filecomp,ICAL_ANY_COMPONENT);
	icalcompiter_deref(&i)!= 0; icalcompiter_next(&i)){
	
	icalcomponent *this = icalcompiter_deref(&i);

	if (this == comp){
	    found = 1;
	    break;
	}
    }

    if (found != 1){
	icalerror_warn("icaldirset_remove_component: component is not part of current cluster");
	icalerror_set_errno(ICAL_USAGE_ERROR);
	return ICAL_USAGE_ERROR;
    }

    icalcluster_remove_component(dset->cluster,comp);

    /* icalcluster_mark(impl->cluster); */

    /* If the removal emptied the fileset, get the next fileset */
    if( icalcluster_count_components(dset->cluster,ICAL_ANY_COMPONENT)==0){
      icalerrorenum error = icaldirset_next_cluster(dset);

      if(dset->cluster != 0 && error == ICAL_NO_ERROR){
	icalcluster_get_first_component(dset->cluster);
	} else {
	    /* HACK. Not strictly correct for impl->cluster==0 */
	    return error;
	}
    } else {
	/* Do nothing */
    }

    return ICAL_NO_ERROR;
}



int icaldirset_count_components(icalset* store,
			       icalcomponent_kind kind)
{
    /* HACK, not implemented */
    assert(0);

    return 0;
}


icalcomponent* icaldirset_fetch_match(icalset* set, icalcomponent *c)
{
    fprintf(stderr," icaldirset_fetch_match is not implemented\n");
    assert(0);
    return 0;
}


icalcomponent* icaldirset_fetch(icalset* set, const char* uid)
{
    icaldirset *dset = (icaldirset*)set;
    icalgauge *gauge;
    icalgauge *old_gauge;
    icalcomponent *c;
    char sql[256];

    icalerror_check_arg_rz( (set!=0), "set");
    icalerror_check_arg_rz( (uid!=0), "uid");

    snprintf(sql, 256, "SELECT * FROM VEVENT WHERE UID = \"%s\"", uid);
    
    gauge = icalgauge_new_from_sql(sql, 0);

    old_gauge = dset->gauge;
    dset->gauge = gauge;

    c= icaldirset_get_first_component(set);

    dset->gauge = old_gauge;

    icalgauge_free(gauge);

    return c;
}


int icaldirset_has_uid(icalset* set, const char* uid)
{
    icalcomponent *c;

    icalerror_check_arg_rz( (set!=0), "set");
    icalerror_check_arg_rz( (uid!=0), "uid");
    
    /* HACK. This is a temporary implementation. _has_uid should use a
       database, and _fetch should use _has_uid, not the other way
       around */
    c = icaldirset_fetch(set,uid);

    return c!=0;

}


icalerrorenum icaldirset_select(icalset* set, icalgauge* gauge)
{
  icaldirset *dset = (icaldirset*)set;

  icalerror_check_arg_re( (set!=0), "set",ICAL_BADARG_ERROR);
    icalerror_check_arg_re( (gauge!=0), "gauge",ICAL_BADARG_ERROR);

  dset->gauge = gauge;

    return ICAL_NO_ERROR;
}


icalerrorenum icaldirset_modify(icalset* set, 
				icalcomponent *old,
			       icalcomponent *new)
{
    assert(0);
    return ICAL_NO_ERROR; /* HACK, not implemented */

}


void icaldirset_clear(icalset* set)
{

    assert(0);
    return;
    /* HACK, not implemented */
}

icalcomponent* icaldirset_get_current_component(icalset* set)
{
  icaldirset *dset = (icaldirset*)set;

  if (dset->cluster == 0){
    icaldirset_get_first_component(set);
    }
  if(dset->cluster == 0){
	return 0;
    }

  return icalcluster_get_current_component(dset->cluster);
}


icalcomponent* icaldirset_get_first_component(icalset* set)
{
  icaldirset *dset = (icaldirset*)set;

    icalerrorenum error;
    char path[ICAL_PATH_MAX];

  error = icaldirset_read_directory(dset);

    if (error != ICAL_NO_ERROR){
	icalerror_set_errno(error);
	return 0;
    }

  dset->directory_iterator = pvl_head(dset->directory);
    
  if (dset->directory_iterator == 0){
	icalerror_set_errno(error);
	return 0;
    }
    
  snprintf(path,ICAL_PATH_MAX,"%s/%s",
	   dset->dir,
	   (char*)pvl_data(dset->directory_iterator));

    /* If the next cluster we need is different than the current cluster, 
       delete the current one and get a new one */

  if(dset->cluster != 0 && strcmp(path,icalcluster_key(dset->cluster)) != 0 ){
    icalcluster_free(dset->cluster);
    dset->cluster = 0;
    }
    
  if (dset->cluster == 0){
    dset->cluster = icalfileset_produce_icalcluster(path);

    if (dset->cluster == 0){
	    error = icalerrno;
	}
    } 

    if (error != ICAL_NO_ERROR){
	icalerror_set_errno(error);
	return 0;
    }

  dset->first_component = 1;

  return icaldirset_get_next_component(set);
}


icalcomponent* icaldirset_get_next_component(icalset* set)
{
  icaldirset *dset = (icaldirset*)set;
    icalcomponent *c;
    icalerrorenum error;

  icalerror_check_arg_rz( (set!=0), "set");


  if(dset->cluster == 0){
	icalerror_warn("icaldirset_get_next_component called with a NULL cluster (Caller must call icaldirset_get_first_component first");
	icalerror_set_errno(ICAL_USAGE_ERROR);
	return 0;

    }

    /* Set the component iterator for the following for loop */
  if (dset->first_component == 1){
    icalcluster_get_first_component(dset->cluster);
    dset->first_component = 0;
    } else {
    icalcluster_get_next_component(dset->cluster);
    }

    while(1){
	/* Iterate through all of the objects in the cluster*/
    for( c = icalcluster_get_current_component(dset->cluster);
	     c != 0;
	 c = icalcluster_get_next_component(dset->cluster)){
	    
	    /* If there is a gauge defined and the component does not
	       pass the gauge, skip the rest of the loop */

      if (dset->gauge != 0 && icalgauge_compare(dset->gauge,c) == 0){
		continue;
	    }

	    /* Either there is no gauge, or the component passed the
	       gauge, so return it*/

	    return c;
	}

	/* Fell through the loop, so the component we want is not
	   in this cluster. Load a new cluster and try again.*/

    error = icaldirset_next_cluster(dset);

    if(dset->cluster == 0 || error != ICAL_NO_ERROR){
	    /* No more clusters */
	    return 0;
	} else {
      c = icalcluster_get_first_component(dset->cluster);

	    return c;
	}
	
    }

    return 0; /* Should never get here */
}

icalsetiter icaldirset_begin_component(icalset* set, icalcomponent_kind kind, icalgauge* gauge)
{
    icalsetiter itr = icalsetiter_null;
    icaldirset *fset = (icaldirset*) set;

    icalerror_check_arg_re((fset!=0), "set", icalsetiter_null);

    itr.iter.kind = kind;
    itr.gauge = gauge;

    /* TO BE IMPLEMENTED */
    return icalsetiter_null;
}

icalcomponent* icaldirsetiter_to_next(icalset* set, icalsetiter* i)
{
    /* TO BE IMPLEMENTED */
    return NULL;
}

icalcomponent* icaldirsetiter_to_prior(icalset* set, icalsetiter* i)
{
    /* TO BE IMPLEMENTED */
    return NULL;
}
