| /** |
| * Copyright 2010 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| // Author: jmarantz@google.com (Joshua Marantz) |
| |
| #include "public/add_head_filter.h" |
| |
| #include "net/instaweb/htmlparse/public/html_parse.h" |
| #include "net/instaweb/htmlparse/public/html_element.h" |
| |
| namespace net_instaweb { |
| |
| AddHeadFilter::AddHeadFilter(HtmlParse* html_parse, bool combine_multiple_heads) |
| : html_parse_(html_parse), |
| combine_multiple_heads_(combine_multiple_heads), |
| found_head_(false), |
| s_head_(html_parse->Intern("head")), |
| s_body_(html_parse->Intern("body")), |
| head_element_(NULL) { |
| } |
| |
| void AddHeadFilter::StartDocument() { |
| found_head_ = false; |
| head_element_ = NULL; |
| } |
| |
| void AddHeadFilter::StartElement(HtmlElement* element) { |
| if (!found_head_) { |
| if (element->tag() == s_body_) { |
| head_element_ = html_parse_->NewElement( |
| element->parent(), s_head_); |
| html_parse_->InsertElementBeforeElement(element, head_element_); |
| found_head_ = true; |
| } else if (element->tag() == s_head_) { |
| found_head_ = true; |
| head_element_ = element; |
| } |
| } |
| } |
| |
| void AddHeadFilter::EndElement(HtmlElement* element) { |
| // Detect elements that are children of a subsequent head. Move them |
| // into the first head if possible. |
| if (combine_multiple_heads_ && found_head_ && (head_element_ != NULL) && |
| html_parse_->IsRewritable(head_element_)) { |
| if ((element->tag() == s_head_) && (element != head_element_)) { |
| // There should be no elements left in the subsequent head, so |
| // remove it. |
| bool moved = html_parse_->MoveCurrentInto(head_element_); |
| CHECK(moved) << "failed to move new head under old head"; |
| bool deleted = html_parse_->DeleteSavingChildren(element); |
| CHECK(deleted) << "failed to delete extra head"; |
| } |
| } |
| } |
| |
| void AddHeadFilter::Flush() { |
| head_element_ = NULL; |
| } |
| |
| void AddHeadFilter::EndDocument() { |
| if (!found_head_) { |
| // In order to insert a <head> in a docucument that lacks one, we |
| // must first find the body. If we get through the whole doc without |
| // finding a <head> or a <body> then this filter will have failed to |
| // add a head. |
| html_parse_->ErrorHere("Reached end of document without finding <body>"); |
| } |
| } |
| |
| } // namespace net_instaweb |
