/*
  Copyright (C) 2000-2004 SKYRIX Software AG

  This file is part of OpenGroupware.org.

  OGo is free software; you can redistribute it and/or modify it under
  the terms of the GNU Lesser General Public License as published by the
  Free Software Foundation; either version 2, or (at your option) any
  later version.

  OGo 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 Lesser General Public
  License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with OGo; see the file COPYING.  If not, write to the
  Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
  02111-1307, USA.
*/

#include "iCalEvent.h"
#include "iCalPerson.h"
#include "iCalEventChanges.h"
#include "iCalRenderer.h"
#include "common.h"

@interface NSString(DurationTimeInterval)
- (NSTimeInterval)durationAsTimeInterval;
@end

@implementation iCalEvent

- (void)dealloc {
  [self->duration release];
  [self->endDate  release];
  [super dealloc];
}

/* accessors */

- (void)setEndDate:(NSCalendarDate *)_date {
  id tmp;
  if (self->endDate == _date) return;
  tmp = self->endDate;
  self->endDate = [_date retain];
  [tmp release];
}
- (NSCalendarDate *)endDate {
  if ([self hasEndDate])
    return self->endDate;
  
  if ([self hasDuration] && (self->startDate != nil)) {
    return [[self startDate] dateByAddingYears:0 months:0 days:0
			     hours:0 minutes:0 
			     seconds:[self durationAsTimeInterval]];
  }
  return nil;
}
- (BOOL)hasEndDate {
  return self->endDate ? YES : NO;
}

- (void)setTransp:(NSString *)_transp {
  /* ignore transp ... (used by Evo 'TRANSP:OPAQUE') */
}

- (void)setDuration:(NSString *)_value {
  ASSIGNCOPY(self->duration, _value);
}
- (NSString *)duration {
  // eg: "DURATION:PT1H"
  if ([self hasDuration])
    return self->duration;
  
  // TODO: calculate
  return nil;
}
- (BOOL)hasDuration {
  return self->duration ? YES : NO;
}
- (NSTimeInterval)durationAsTimeInterval {
  /*
    eg: DURATION:PT1H
    P      - "period"
    P2H30M - "2 hours 30 minutes"

     dur-value  = (["+"] / "-") "P" (dur-date / dur-time / dur-week)

     dur-date   = dur-day [dur-time]
     dur-time   = "T" (dur-hour / dur-minute / dur-second)
     dur-week   = 1*DIGIT "W"
     dur-hour   = 1*DIGIT "H" [dur-minute]
     dur-minute = 1*DIGIT "M" [dur-second]
     dur-second = 1*DIGIT "S"
     dur-day    = 1*DIGIT "D"
  */
  
  if (self->duration)
    return [self->duration durationAsTimeInterval];
  
  if (self->endDate != nil && self->startDate != nil)
    /* calculate duration using enddate */
    return [[self endDate] timeIntervalSinceDate:[self startDate]];
  
  return 0.0;
}

/* ical typing */

- (NSString *)entityName {
  return @"vevent";
}

/* descriptions */

- (NSString *)description {
  NSMutableString *ms;

  ms = [NSMutableString stringWithCapacity:128];
  [ms appendFormat:@"<0x%08X[%@]:", self, NSStringFromClass([self class])];

  if (self->uid)       [ms appendFormat:@" uid=%@", self->uid];
  if (self->startDate) [ms appendFormat:@" from=%@", self->startDate];
  if (self->endDate)   [ms appendFormat:@" to=%@", self->endDate];
  if (self->summary)   [ms appendFormat:@" summary=%@", self->summary];
  
  if (self->organizer)
    [ms appendFormat:@" organizer=%@", self->organizer];
  if (self->attendees)
    [ms appendFormat:@" attendees=%@", self->attendees];
  
  if ([self hasAlarms])
    [ms appendFormat:@" alarms=%@", self->alarms];
  
  [ms appendString:@">"];
  return ms;
}

/* changes */

- (iCalEventChanges *)getChangesRelativeToEvent:(iCalEvent *)_event {
  return [iCalEventChanges changesFromEvent:_event
                           toEvent:self];
}

/* generating iCal content */

- (NSString *)vEventString {
  return [[iCalRenderer sharedICalendarRenderer] vEventStringForEvent:self];
}

@end /* iCalEvent */

@implementation NSString(DurationTimeInterval)

- (NSTimeInterval)durationAsTimeInterval {
  /*
    eg: DURATION:PT1H
    P      - "period"
    P2H30M - "2 hours 30 minutes"

     dur-value  = (["+"] / "-") "P" (dur-date / dur-time / dur-week)

     dur-date   = dur-day [dur-time]
     dur-time   = "T" (dur-hour / dur-minute / dur-second)
     dur-week   = 1*DIGIT "W"
     dur-hour   = 1*DIGIT "H" [dur-minute]
     dur-minute = 1*DIGIT "M" [dur-second]
     dur-second = 1*DIGIT "S"
     dur-day    = 1*DIGIT "D"
  */
  unsigned       i, len;
  NSTimeInterval ti;
  BOOL           isTime;
  int            val;
    
  if (![self hasPrefix:@"P"]) {
    NSLog(@"Cannot parse iCal duration value: '%@'", self);
    return 0.0;
  }
    
  ti  = 0.0;
  val = 0;
  for (i = 1, len = [self length], isTime = NO; i < len; i++) {
    unichar c;
      
    c = [self characterAtIndex:i];
    if (c == 't' || c == 'T') {
      isTime = YES;
      val = 0;
      continue;
    }
      
    if (isdigit(c)) {
      val = (val * 10) + (c - 48);
      continue;
    }
      
    switch (c) {
    case 'W': /* week */
      ti += (val * 7 * 24 * 60 * 60);
      break;
    case 'D': /* day  */
      ti += (val * 24 * 60 * 60);
      break;
    case 'H': /* hour */
      ti += (val * 60 * 60);
      break;
    case 'M': /* min  */
      ti += (val * 60);
      break;
    case 'S': /* sec  */
      ti += val;
      break;
    default:
      [self logWithFormat:@"cannot process duration unit: '%c'", c];
      break;
    }
    val = 0;
  }
  return ti;
}

@end /* NSString(DurationTimeInterval) */