backend/ev-page-cache.c

   1 #include "ev-page-cache.h"
   2 #include "ev-job-queue.h"
   3 #include <stdlib.h>
   4 #include <string.h>
   5
   6 typedef struct _EvPageCacheInfo
   7 {
   8         double width;
   9         double height;
  10 }
  11 EvPageCacheInfo;
  12
  13
  14 struct _EvPageCache
  15 {
  16         GObject parent;
  17
  18         gint current_page;
  19         int n_pages;
  20         char *title;
  21         char **page_labels;
  22
  23         gint max_label_chars;
  24         gboolean has_labels;
  25         gboolean uniform;
  26
  27         double uniform_width;
  28         double uniform_height;
  29
  30         double  max_width;
  31         double  max_height;
  32         double* height_to_page;
  33         double* dual_height_to_page;
  34
  35         EvPageCacheInfo *size_cache;
  36         EvDocumentInfo *page_info;
  37 };
  38
  39 struct _EvPageCacheClass
  40 {
  41         GObjectClass parent_class;
  42
  43         void (* page_changed) (EvPageCache *page_cache, gint page);
  44 };
  45
  46 enum
  47 {
  48         PAGE_CHANGED,
  49         N_SIGNALS,
  50 };
  51
  52 static guint signals[N_SIGNALS] = {0, };
  53
  54 static void ev_page_cache_init       (EvPageCache      *page_cache);
  55 static void ev_page_cache_class_init (EvPageCacheClass *page_cache);
  56 static void ev_page_cache_finalize   (GObject *object);
  57
  58 G_DEFINE_TYPE (EvPageCache, ev_page_cache, G_TYPE_OBJECT)
  59
  60 static void
  61 ev_page_cache_init (EvPageCache *page_cache)
  62 {
  63         page_cache->current_page = -1;
  64         page_cache->max_label_chars = 0;
  65 }
  66
  67 static void
  68 ev_page_cache_class_init (EvPageCacheClass *class)
  69 {
  70         GObjectClass *object_class;
  71
  72         object_class = G_OBJECT_CLASS (class);
  73
  74         object_class->finalize = ev_page_cache_finalize;
  75
  76         signals [PAGE_CHANGED] =
  77                 g_signal_new ("page-changed",
  78                               EV_TYPE_PAGE_CACHE,
  79                               G_SIGNAL_RUN_LAST,
  80                               G_STRUCT_OFFSET (EvPageCacheClass, page_changed),
  81                               NULL, NULL,
  82                               g_cclosure_marshal_VOID__INT,
  83                               G_TYPE_NONE, 1,
  84                               G_TYPE_INT);
  85
  86 }
  87
  88 static void
  89 ev_page_cache_finalize (GObject *object)
  90 {
  91         EvPageCache *page_cache;
  92
  93         page_cache = EV_PAGE_CACHE (object);
  94
  95         g_free (page_cache->title);
  96         g_free (page_cache->size_cache);
  97         g_free (page_cache->height_to_page);
  98         g_free (page_cache->dual_height_to_page);
  99
 100         ev_document_info_free (page_cache->page_info);
 101 }
 102
 103 EvPageCache *
 104 _ev_page_cache_new (EvDocument *document)
 105 {
 106         EvDocumentInfo *doc_info;
 107         EvPageCache *page_cache;
 108         EvPageCacheInfo *info;
 109         gint i;
 110         double saved_height;
 111
 112         page_cache = (EvPageCache *) g_object_new (EV_TYPE_PAGE_CACHE, NULL);
 113
 114         ev_document_doc_mutex_lock ();
 115
 116         /* We read page information out of the document */
 117
 118         /* Assume all pages are the same size until proven otherwise */
 119         page_cache->uniform = TRUE;
 120         page_cache->has_labels = FALSE;
 121         page_cache->n_pages = ev_document_get_n_pages (document);
 122         page_cache->page_labels = g_new0 (char *, page_cache->n_pages);
 123         page_cache->max_width = 0;
 124         page_cache->max_height = 0;
 125
 126         doc_info = ev_document_get_info (document);
 127         if (doc_info->fields_mask & EV_DOCUMENT_INFO_TITLE) {
 128                 page_cache->title = g_strdup (doc_info->title);
 129         } else {
 130                 page_cache->title = NULL;
 131         }
 132         g_free (doc_info);
 133
 134         for (i = 0; i < page_cache->n_pages; i++) {
 135                 double page_width = 0;
 136                 double page_height = 0;
 137
 138                 ev_document_get_page_size (document, i, &page_width, &page_height);
 139
 140                 page_cache->page_labels[i] = ev_document_get_page_label (document, i);
 141
 142                 if (page_cache->page_labels[i] != NULL) {
 143
 144                         page_cache->max_label_chars = MAX(page_cache->max_label_chars,
 145                                                             g_utf8_strlen (page_cache->page_labels[i], 256));
 146                         if (!page_cache->has_labels) {
 147                                 gchar *expected_label;
 148
 149                                 expected_label = g_strdup_printf ("%d", i + 1);
 150                                 if (strcmp (expected_label, page_cache->page_labels[i]))
 151                                         page_cache->has_labels = TRUE;
 152                                 g_free (expected_label);
 153                         }
 154                 }
 155
 156                 if (page_width > page_cache->max_width) {
 157                         page_cache->max_width = page_width;
 158                 }
 159
 160                 if (page_height > page_cache->max_height) {
 161                         page_cache->max_height = page_height;
 162                 }
 163
 164                 if (i == 0) {
 165                         page_cache->uniform_width = page_width;
 166                         page_cache->uniform_height = page_height;
 167                 } else if (page_cache->uniform &&
 168                            (page_cache->uniform_width != page_width ||
 169                             page_cache->uniform_height != page_height)) {
 170                         /* It's a different page size.  Backfill the array. */
 171                         int j;
 172
 173                         page_cache->size_cache = g_new0 (EvPageCacheInfo, page_cache->n_pages);
 174
 175                         for (j = 0; j < i; j++) {
 176                                 info = &(page_cache->size_cache [j]);
 177                                 info->width = page_cache->uniform_width;
 178                                 info->height = page_cache->uniform_height;
 179                         }
 180                         page_cache->uniform = FALSE;
 181
 182                 }
 183
 184                 if (! page_cache->uniform) {
 185                         info = &(page_cache->size_cache [i]);
 186
 187                         info->width = page_width;
 188                         info->height = page_height;
 189                 }
 190         }
 191
 192         page_cache->height_to_page = g_new0(double, page_cache->n_pages);
 193         page_cache->dual_height_to_page = g_new0(double, page_cache->n_pages / 2 + 1);
 194
 195         saved_height = 0;
 196         for (i = 0; i < page_cache->n_pages; i++) {
 197
 198                 if (page_cache->uniform) {
 199                         page_cache->height_to_page [i] = (i + 1) * page_cache->uniform_height;
 200                 } else {
 201                         page_cache->height_to_page [i] = saved_height + page_cache->size_cache [i].height;
 202                         saved_height = page_cache->height_to_page [i];
 203                 }
 204         }
 205
 206         saved_height = 0;
 207         for (i = 0; i < page_cache->n_pages; i += 2) {
 208
 209                 if (page_cache->uniform) {
 210                         page_cache->dual_height_to_page [i / 2] = (i / 2 + 1) * page_cache->uniform_height;
 211                 } else {
 212                         if (i == page_cache->n_pages - 1) {
 213                                 page_cache->dual_height_to_page [i / 2] =
 214                                         saved_height + page_cache->size_cache [i].height;
 215                         }
 216                         else {
 217                                 page_cache->dual_height_to_page [i / 2] = saved_height +
 218                                        MAX(page_cache->size_cache [i].height,
 219                                            page_cache->size_cache [i + 1].height);
 220                                 saved_height = page_cache->dual_height_to_page [i / 2];
 221                         }
 222                 }
 223         }
 224
 225         page_cache->page_info = ev_document_get_info (document);
 226
 227         /* make some sanity check assertions */
 228         if (! page_cache->uniform)
 229                 g_assert (page_cache->size_cache != NULL);
 230         if (page_cache->uniform)
 231                 g_assert (page_cache->uniform_width > 0 && page_cache->uniform_height > 0);
 232
 233         ev_document_doc_mutex_unlock ();
 234
 235         if (page_cache->n_pages > 0)
 236                 ev_page_cache_set_current_page (page_cache, 0);
 237
 238         return page_cache;
 239 }
 240
 241 gint
 242 ev_page_cache_get_n_pages (EvPageCache *page_cache)
 243 {
 244         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), 0);
 245
 246         return page_cache->n_pages;
 247 }
 248
 249 gint
 250 ev_page_cache_get_current_page (EvPageCache *page_cache)
 251 {
 252         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), 0);
 253
 254         return page_cache->current_page;
 255 }
 256
 257 void
 258 ev_page_cache_set_current_page (EvPageCache *page_cache,
 259                                 int          page)
 260 {
 261         g_return_if_fail (EV_IS_PAGE_CACHE (page_cache));
 262         g_return_if_fail (page >= 0 || page < page_cache->n_pages);
 263
 264         if (page == page_cache->current_page)
 265                 return;
 266
 267         page_cache->current_page = page;
 268         g_signal_emit (page_cache, signals[PAGE_CHANGED], 0, page);
 269 }
 270
 271 gboolean
 272 ev_page_cache_set_page_label (EvPageCache *page_cache,
 273                               const char  *page_label)
 274 {
 275         gint i, page;
 276         long value;
 277         char *endptr = NULL;
 278
 279         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), FALSE);
 280         g_return_val_if_fail (page_label != NULL, FALSE);
 281
 282         /* First, look for a literal label match */
 283         for (i = 0; i < page_cache->n_pages; i ++) {
 284                 if (page_cache->page_labels[i] != NULL &&
 285                     ! strcmp (page_label, page_cache->page_labels[i])) {
 286                         ev_page_cache_set_current_page (page_cache, i);
 287                         return TRUE;
 288                 }
 289         }
 290
 291         /* Next, parse the label, and see if the number fits */
 292         value = strtol (page_label, &endptr, 10);
 293         if (endptr[0] == '\0') {
 294                 /* Page number is an integer */
 295                 page = MIN (G_MAXINT, value);
 296
 297                 /* convert from a page label to a page offset */
 298                 page --;
 299                 if (page >= 0 &&
 300                     page < page_cache->n_pages &&
 301                     page_cache->page_labels[page] == NULL) {
 302                         ev_page_cache_set_current_page (page_cache, page);
 303                         return TRUE;
 304                 }
 305         }
 306
 307         return FALSE;
 308 }
 309
 310 void
 311 ev_page_cache_set_link (EvPageCache *page_cache,
 312                         EvLink      *link)
 313 {
 314         g_return_if_fail (EV_IS_PAGE_CACHE (page_cache));
 315         g_return_if_fail (EV_IS_LINK (link));
 316
 317         ev_page_cache_set_current_page (page_cache, ev_link_get_page (link));
 318 }
 319
 320 char *
 321 ev_page_cache_get_title (EvPageCache *page_cache)
 322 {
 323         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), NULL);
 324
 325         return page_cache->title;
 326 }
 327
 328 void
 329 ev_page_cache_get_size (EvPageCache *page_cache,
 330                         gint         page,
 331                         gfloat       scale,
 332                         gint        *width,
 333                         gint        *height)
 334 {
 335         g_return_if_fail (EV_IS_PAGE_CACHE (page_cache));
 336         g_return_if_fail (page >= 0 && page < page_cache->n_pages);
 337
 338         if (page_cache->uniform) {
 339                 if (width)
 340                         *width = page_cache->uniform_width;
 341                 if (height)
 342                         *height = page_cache->uniform_height;
 343         } else {
 344                 EvPageCacheInfo *info;
 345
 346                 info = &(page_cache->size_cache [page]);
 347
 348                 if (width)
 349                         *width = info->width;
 350                 if (height)
 351                         *height = info->height;
 352         }
 353
 354         if (width)
 355                 *width = (int) ((*width) * scale + 0.5);
 356         if (width)
 357                 *height = (int) ((*height) * scale + 0.5);
 358
 359 }
 360
 361
 362 void
 363 ev_page_cache_get_max_width      (EvPageCache *page_cache,
 364                                   gfloat       scale,
 365                                   gint        *width)
 366 {
 367         g_return_if_fail (EV_IS_PAGE_CACHE (page_cache));
 368
 369         if (width)
 370                 *width = page_cache->max_width * scale;
 371 }
 372
 373 void
 374 ev_page_cache_get_max_height      (EvPageCache *page_cache,
 375                                    gfloat       scale,
 376                                    gint        *height)
 377 {
 378         g_return_if_fail (EV_IS_PAGE_CACHE (page_cache));
 379
 380         if (height)
 381                 *height = page_cache->max_height * scale;
 382 }
 383
 384 void
 385 ev_page_cache_get_height_to_page (EvPageCache *page_cache,
 386                                   gint page,
 387                                   gfloat       scale,
 388                                   gint        *height,
 389                                   gint        *dual_height)
 390 {
 391         double result = 0.0;
 392         double dual_result = 0.0;
 393
 394         g_return_if_fail (EV_IS_PAGE_CACHE (page_cache));
 395
 396         if (page > 0)
 397                 result = page_cache->height_to_page [page - 1];
 398
 399         if (height)
 400                 *height = result * scale;
 401
 402         if (page > 1)
 403                 dual_result = page_cache->dual_height_to_page [page / 2 - 1];
 404
 405         if (dual_height)
 406                 *dual_height = dual_result * scale;
 407 }
 408
 409 gint
 410 ev_page_cache_get_max_label_chars (EvPageCache *page_cache)
 411 {
 412         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), 0);
 413
 414         return page_cache->max_label_chars;
 415 }
 416
 417 gchar *
 418 ev_page_cache_get_page_label (EvPageCache *page_cache,
 419                               gint         page)
 420 {
 421         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), NULL);
 422         g_return_val_if_fail (page >= 0 && page < page_cache->n_pages, NULL);
 423
 424         if (page_cache->page_labels[page] == NULL)
 425                 return g_strdup_printf ("%d", page + 1);
 426
 427         return g_strdup (page_cache->page_labels[page]);
 428 }
 429
 430 gboolean
 431 ev_page_cache_has_nonnumeric_page_labels (EvPageCache *page_cache)
 432 {
 433         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), FALSE);
 434         return page_cache->has_labels;
 435 }
 436
 437 const EvDocumentInfo *
 438 ev_page_cache_get_info (EvPageCache *page_cache)
 439 {
 440         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), NULL);
 441
 442         return page_cache->page_info;
 443 }
 444
 445
 446 gboolean
 447 ev_page_cache_next_page (EvPageCache *page_cache)
 448 {
 449         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), FALSE);
 450
 451         if (page_cache->current_page >= page_cache->n_pages - 1)
 452                 return FALSE;
 453
 454         ev_page_cache_set_current_page (page_cache, page_cache->current_page + 1);
 455         return TRUE;
 456
 457 }
 458
 459 gboolean
 460 ev_page_cache_prev_page (EvPageCache *page_cache)
 461 {
 462         g_return_val_if_fail (EV_IS_PAGE_CACHE (page_cache), FALSE);
 463
 464         if (page_cache->current_page <= 0)
 465                 return FALSE;
 466
 467         ev_page_cache_set_current_page (page_cache, page_cache->current_page - 1);
 468         return TRUE;
 469 }
 470