-gdoc opt, clean Google Docs HTML; fr Dave Raggett

src/gdoc.c

@@ -0,0 +1,180 @@
+/*
+  clean.c -- clean up misuse of presentation markup
+
+  (c) 1998-2008 (W3C) MIT, ERCIM, Keio University
+  See tidy.h for the copyright notice.
+
+  CVS Info :
+
+    $Author: arnaud02 $ 
+    $Date: 2008/10/14 12:18:10 $ 
+    $Revision: 1.111 $ 
+
+  Filters from other formats such as Microsoft Word
+  often make excessive use of presentation markup such
+  as font tags, B, I, and the align attribute. By applying
+  a set of production rules, it is straight forward to
+  transform this to use CSS.
+
+  Some rules replace some of the children of an element by
+  style properties on the element, e.g.
+
+  <p><b>...</b></p> -> <p style="font-weight: bold">...</p>
+
+  Such rules are applied to the element's content and then
+  to the element itself until none of the rules more apply.
+  Having applied all the rules to an element, it will have
+  a style attribute with one or more properties. 
+
+  Other rules strip the element they apply to, replacing
+  it by style properties on the contents, e.g.
+  
+  <dir><li><p>...</li></dir> -> <p style="margin-left 1em">...
+      
+  These rules are applied to an element before processing
+  its content and replace the current element by the first
+  element in the exposed content.
+
+  After applying both sets of rules, you can replace the
+  style attribute by a class value and style rule in the
+  document head. To support this, an association of styles
+  and class names is built.
+
+  A naive approach is to rely on string matching to test
+  when two property lists are the same. A better approach
+  would be to first sort the properties before matching.
+
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "tidy-int.h"
+#include "gdoc.h"
+#include "lexer.h"
+#include "parser.h"
+#include "tags.h"
+#include "attrs.h"
+#include "message.h"
+#include "tmbstr.h"
+#include "utf8.h"
+
+/*
+  Extricate "element", replace it by its content and delete it.
+*/
+static void DiscardContainer( TidyDocImpl* doc, Node *element, Node **pnode)
+{
+    if (element->content)
+    {
+        Node *node, *parent = element->parent;
+
+        element->last->next = element->next;
+
+        if (element->next)
+        {
+            element->next->prev = element->last;
+        }
+        else
+            parent->last = element->last;
+
+        if (element->prev)
+        {
+            element->content->prev = element->prev;
+            element->prev->next = element->content;
+        }
+        else
+            parent->content = element->content;
+
+        for (node = element->content; node; node = node->next)
+            node->parent = parent;
+
+        *pnode = element->content;
+
+        element->next = element->content = NULL;
+        TY_(FreeNode)(doc, element);
+    }
+    else
+    {
+        *pnode = TY_(DiscardElement)(doc, element);
+    }
+}
+
+static void CleanNode( TidyDocImpl* doc, Node *node )
+{
+    Node *child, *next;
+
+    if (node->content)
+    {
+        for (child = node->content; child != NULL; child = next)
+        {
+            next = child->next;
+
+            if (TY_(nodeIsElement)(child))
+            {
+                if (nodeIsSTYLE(child))
+                    TY_(DiscardElement)(doc, child);
+                if (nodeIsP(child) && !child->content)
+                    TY_(DiscardElement)(doc, child);
+                else if (nodeIsSPAN(child))
+                    DiscardContainer( doc, child, &next);
+                else if (nodeIsA(child) && !child->content)
+                 {
+                    AttVal *id = TY_(GetAttrByName)( child, "name" );
+
+                    if (id)
+                        TY_(RepairAttrValue)( doc, child->parent, "id", id->value );
+
+                    TY_(DiscardElement)(doc, child);
+                }
+                else
+                {
+                    if (child->attributes)
+                        TY_(DropAttrByName)( doc, child, "class" );
+
+                    CleanNode(doc, child);
+                }
+            }
+        }
+    }
+}
+
+/* insert meta element to force browser to recognize doc as UTF8 */
+static void SetUTF8( TidyDocImpl* doc )
+{
+    Node *head = TY_(FindHEAD)( doc );
+
+    if (head)
+    {
+        Node *node = TY_(InferredTag)(doc, TidyTag_META);
+        TY_(AddAttribute)( doc, node, "http-equiv", "Content-Type" );
+        TY_(AddAttribute)( doc, node, "content", "text/html; charset=UTF-8" );
+        TY_(InsertNodeAtStart)( head, node );
+    }
+}
+
+/* clean html exported by Google Docs
+
+    - strip the script element, as the style sheet is a mess
+    - strip class attributes
+    - strip span elements, leaving their content in place
+    - replace <a name=...></a> by id on parent element
+    - strip empty <p> elements
+*/
+void TY_(CleanGoogleDocument)( TidyDocImpl* doc )
+{
+    /* placeholder.  CleanTree()/CleanNode() will not
+    ** zap root element 
+    */
+    CleanNode( doc, &doc->root );
+    SetUTF8( doc );
+}
+
+/*
+ * local variables:
+ * mode: c
+ * indent-tabs-mode: nil
+ * c-basic-offset: 4
+ * eval: (c-set-offset 'substatement-open 0)
+ * end:
+ */

src/gdoc.h

@@ -0,0 +1,26 @@
+#ifndef __GDOC_H__
+#define __GDOC_H__
+
+/* gdoc.h -- clean up html exported by Google Docs
+
+  (c) 2012 (W3C) MIT, ERCIM, Keio University
+  See tidy.h for the copyright notice.
+
+  CVS Info:
+    $Author: dsr $ 
+    $Date: 2012/06/07 13:14:00 $ 
+    $Revision: 1.0 $ 
+
+*/
+
+/* clean html exported by Google Docs
+
+    - strip the script element, as the style sheet is a mess
+    - strip class attributes
+    - strip span elements, leaving their content in place
+    - replace <a name=...></a> by id on parent element
+    - strip empty <p> elements
+*/
+void TY_(CleanGoogleDocument)( TidyDocImpl* doc );
+
+#endif /* __GDOC_H__ */