kmid/songlist.cpp

   1 /**************************************************************************
   2
   3     songlist.cc  - class SongList, which holds a list of songs (collection)
   4     Copyright (C) 1997,98  Antonio Larrosa Jimenez
   5
   6     This program is free software; you can redistribute it and/or modify
   7     it under the terms of the GNU General Public License as published by
   8     the Free Software Foundation; either version 2 of the License, or
   9     (at your option) any later version.
  10
  11     This program is distributed in the hope that it will be useful,
  12     but WITHOUT ANY WARRANTY; without even the implied warranty of
  13     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14     GNU General Public License for more details.
  15
  16     You should have received a copy of the GNU General Public License
  17     along with this program; if not, write to the Free Software
  18     Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  19
  20     Send comments and bug fixes to larrosa@kde.org
  21     or to Antonio Larrosa, Rio Arnoya, 10 5B, 29006 Malaga, Spain
  22
  23 ***************************************************************************/
  24 #include "songlist.h"
  25 #include <stdlib.h>
  26 #include <stdio.h>
  27 #include <string.h>
  28
  29 SongList::SongList(void)
  30 {
  31     list=NULL;
  32     last=NULL;
  33     active=NULL;
  34     ntotal=0;
  35 }
  36
  37 SongList::SongList(SongList &src)
  38 {
  39     list=last=active=NULL;
  40     ntotal=0;
  41     src.iteratorStart();
  42     while (!src.iteratorAtEnd())
  43     {
  44         AddSong(src.getIteratorName());
  45         src.iteratorNext();
  46     }
  47     if (src.active!=NULL) active=getSongid(src.active->id);
  48 }
  49
  50 SongList::~SongList()
  51 {
  52     clean();
  53     Song *ptr=list;
  54     active=last=NULL;
  55     ntotal=0;
  56
  57     while (ptr!=NULL)
  58     {
  59         list=ptr->next;
  60         delete ptr->name;
  61         delete ptr;
  62         ptr=list;
  63     }
  64
  65 }
  66
  67 SongList::Song *SongList::getSongid(int id)
  68 {
  69     Song *ptr=list;
  70     while ((ptr!=NULL)&&(ptr->id!=id))
  71         ptr=ptr->next;
  72
  73     return ptr;
  74 }
  75
  76 int SongList::AddSong(const char *song)
  77 {
  78     if (!song) return 0;
  79
  80     if (last==NULL)
  81     {
  82         last=new Song;
  83         list=last;
  84     }
  85     else
  86     {
  87         last->next=new Song;
  88         last=last->next;
  89     }
  90     last->name=new char[strlen(song)+1];
  91     strcpy(last->name,song);
  92     last->id= ++ntotal;
  93     last->next=NULL;
  94     if (active==NULL) active=last;
  95     return last->id;
  96 }
  97
  98 void SongList::DelSong(int id)
  99 {
 100     Song *ptr;
 101
 102     if (list==NULL) return;
 103     if (id==1)
 104     {
 105         if (last->id==1)
 106         {
 107             list=last=active=NULL;
 108             ntotal=0;
 109         }
 110         else
 111         {
 112             ptr=list;
 113             if (active->id==1) active=list->next;
 114             list=list->next;
 115             delete ptr->name;
 116             delete ptr;
 117             ntotal--;
 118
 119             regenerateid(list,1);
 120         }
 121         return;
 122     }
 123     Song *ptr_prev=getSongid(id-1);
 124     ptr=ptr_prev->next;
 125     if (last->id==id) last=ptr_prev;
 126     if (active->id==id)
 127         if (active->next!=NULL) active=active->next;
 128         else active=ptr_prev;
 129
 130     ntotal--;
 131     ptr_prev->next=ptr->next;
 132     delete ptr->name;
 133     delete ptr;
 134     regenerateid(ptr_prev->next,id);
 135
 136 }
 137
 138 void SongList::regenerateid(Song *song,int id)
 139 {
 140     Song *tmp=song;
 141     int i=id;
 142     while (tmp!=NULL)
 143     {
 144         tmp->id=i++;
 145         tmp=tmp->next;
 146     }
 147     ntotal=i-1;
 148 }
 149
 150 void SongList::setActiveSong(int id)
 151 {
 152     Song *tmp=getSongid(id);
 153     if (tmp!=NULL) active=tmp;
 154 }
 155
 156 char *SongList::getName(int id)
 157 {
 158     Song *tmp=getSongid(id);
 159     if (tmp!=NULL) return tmp->name;
 160     return NULL;
 161 }
 162
 163 /*
 164 void SongList::saveList(FILE *fh)
 165 {
 166     Song *ptr=list;
 167     while (ptr!=NULL)
 168     {
 169         fputs(fh,ptr->name);
 170         ptr=ptr->next;
 171     }
 172 }
 173 */
 174
 175 void SongList::iteratorStart(void)
 176 {
 177     it=list;
 178 }
 179
 180 void SongList::iteratorNext(void)
 181 {
 182     if (it!=NULL) it=it->next;
 183 }
 184
 185 int SongList::getIteratorID(void)
 186 {
 187     if (it==NULL) return -1;
 188     return it->id;
 189 }
 190
 191 char *SongList::getIteratorName(void)
 192 {
 193     if (it==NULL) return NULL;
 194     return it->name;
 195 }
 196
 197
 198 void SongList::clean(void)
 199 {
 200     Song *tmp=list;
 201     active=last=NULL;
 202     ntotal=0;
 203
 204     while (tmp!=NULL)
 205     {
 206         list=tmp->next;
 207         delete [] tmp->name;
 208         delete tmp;
 209         tmp=list;
 210     }
 211 }
 212
 213 void SongList::copy(SongList &src)
 214 {
 215     clean();
 216     src.iteratorStart();
 217     while (!src.iteratorAtEnd())
 218     {
 219         AddSong(src.getIteratorName());
 220         src.iteratorNext();
 221     }
 222     if (src.active!=NULL) active=getSongid(src.active->id);
 223 }
 224
 225 int SongList::next(void)
 226 {
 227     if (list==NULL) {active=NULL;return 0;};
 228     if (active!=NULL) active=active->next;
 229     if (active==NULL)
 230     {
 231         Song *tmp=list;
 232         while (tmp->next!=NULL) tmp=tmp->next;
 233         active=tmp;
 234         return 0;
 235     }
 236     return 1;
 237 }
 238
 239
 240 void SongList::previous(void)
 241 {
 242     if (list==NULL) {active=NULL;return;};
 243     Song *tmp=list;
 244     while ((tmp->next!=NULL)&&(tmp->next->id!=active->id)) tmp=tmp->next;
 245     if (tmp->next==NULL) {active=list;return;};
 246     active=tmp;
 247 }