[libgepub] Helper functions to convert from res to chapter

[Daniel Garcia Moreno <danigm src gnome org>]

commit 021364bc2f62dc38fa6629f44995a394038306c5
Author: Daniel García Moreno <danigm wadobo com>
Date:   Fri Sep 21 11:50:58 2018 +0200

    Helper functions to convert from res to chapter
    
    The `gepub_doc_resource_uri_to_chapter` and
    `gepub_doc_resource_id_to_chapter` methods are useful to convert a
    resource ID or URI to a chapter number and then use in the
    `gepub_doc_set_chapter` method, to navigate.
    
    This new helper functions can be combined with the new
    `gepub_doc_get_toc` to navigate in the document.
    
    See #6

 libgepub/gepub-doc.c | 87 ++++++++++++++++++++++++++++++++++++++++++++++++++--
 libgepub/gepub-doc.h |  4 +++
 tests/test-gepub.c   |  1 +
 3 files changed, 89 insertions(+), 3 deletions(-)
---
diff --git a/libgepub/gepub-doc.c b/libgepub/gepub-doc.c
index ea8dbba..4059ac5 100644
--- a/libgepub/gepub-doc.c
+++ b/libgepub/gepub-doc.c
@@ -410,10 +410,18 @@ gepub_doc_fill_toc (GepubDoc *doc, gchar *toc_id)
             }
 
             if (!g_strcmp0 ((const gchar *)navchilds->name, "content")) {
-                gchar *uri, *tmpuri;
+                gchar **split;
+                gchar *tmpuri;
                 tmpuri = gepub_utils_get_prop (navchilds, "src");
-                uri = g_strdup_printf ("%s%s", doc->content_base, tmpuri);
-                navpoint->content = uri;
+                // removing # params. Maybe we should store the # params in the
+                // navpoint to use in the future if the doc references to a position
+                // inside the chapter
+                split = g_strsplit (tmpuri, "#", -1);
+
+                // adding the base path
+                navpoint->content = g_strdup_printf ("%s%s", doc->content_base, split[0]);
+
+                g_strfreev (split);
                 g_free (tmpuri);
             }
 
@@ -921,3 +929,76 @@ gepub_doc_get_toc (GepubDoc *doc)
     return doc->toc;
 }
 
+/**
+ * gepub_doc_resource_uri_to_chapter:
+ * @doc: a #GepubDoc
+ * @uri: The resource path
+ *
+ * This method tries to find the resource by path in the doc spine and
+ * will return the index in that list. If the resourse isn't there this method
+ * will return -1.
+
+ * Returns: the chapter index to use with gepub_doc_set_chapter or -1 if the
+ * resource isn't found
+ */
+gint
+gepub_doc_resource_uri_to_chapter (GepubDoc *doc,
+                                   const gchar *uri)
+{
+    GHashTableIter iter;
+    gchar *key;
+    GepubResource *res;
+    gchar *id = NULL;
+
+    g_return_val_if_fail (GEPUB_IS_DOC (doc), -1);
+    g_return_val_if_fail (doc->spine != NULL, -1);
+
+    g_hash_table_iter_init (&iter, doc->resources);
+    while (g_hash_table_iter_next (&iter, (gpointer *)&key, (gpointer *)&res)) {
+        if (!g_strcmp0 (res->uri, uri)) {
+            id = key;
+            break;
+        }
+    }
+
+    if (!id) {
+        return -1;
+    }
+
+    return gepub_doc_resource_id_to_chapter (doc, id);
+}
+
+/**
+ * gepub_doc_resource_id_to_chapter:
+ * @doc: a #GepubDoc
+ * @id: The resource id
+ *
+ * This method tries to find the resource by id in the doc spine and
+ * will return the index in that list. If the resourse isn't there this method
+ * will return -1.
+
+ * Returns: the chapter index to use with gepub_doc_set_chapter or -1 if the
+ * resource isn't found
+ */
+gint
+gepub_doc_resource_id_to_chapter (GepubDoc *doc,
+                                  const gchar *id)
+{
+    GList *spine;
+    gint chapter = 0;
+
+    g_return_val_if_fail (GEPUB_IS_DOC (doc), -1);
+    g_return_val_if_fail (doc->spine != NULL, -1);
+
+    spine = g_list_first (doc->spine);
+    while (spine && spine->data) {
+        if (!g_strcmp0 (spine->data, id)) {
+            return chapter;
+        }
+        chapter++;
+        spine = spine->next;
+    }
+
+    return -1;
+}
+
diff --git a/libgepub/gepub-doc.h b/libgepub/gepub-doc.h
index 4290d92..b24a058 100644
--- a/libgepub/gepub-doc.h
+++ b/libgepub/gepub-doc.h
@@ -77,6 +77,10 @@ void              gepub_doc_set_chapter                     (GepubDoc *doc,
                                                              gint      index);
 
 GList            *gepub_doc_get_toc                         (GepubDoc *doc);
+gint              gepub_doc_resource_uri_to_chapter         (GepubDoc *doc,
+                                                             const gchar *uri);
+gint              gepub_doc_resource_id_to_chapter          (GepubDoc *doc,
+                                                             const gchar *id);
 
 G_END_DECLS
 
diff --git a/tests/test-gepub.c b/tests/test-gepub.c
index afdf714..55ab1a2 100644
--- a/tests/test-gepub.c
+++ b/tests/test-gepub.c
@@ -282,6 +282,7 @@ test_doc_toc (const char *path)
     while (nav && nav->data) {
         GepubNavPoint *point = (GepubNavPoint*)nav->data;
         PTEST ("%02d: %s -> %s\n", (gint)point->playorder, point->label, point->content);
+        PTEST (" -> Chapter: %d\n", gepub_doc_resource_uri_to_chapter (doc, point->content));
         nav = nav->next;
     }