// Copyright (c) 2011 The Chromium Embedded Framework Authors. All rights
// reserved. Use of this source code is governed by a BSD-style license that
// can be found in the LICENSE file.

#include "dom_document_impl.h"
#include "dom_node_impl.h"
#include "cef_thread.h"

#include "base/logging.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebDocument.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebElement.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebFrame.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebNode.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebRange.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebString.h"
#include "third_party/WebKit/Source/WebKit/chromium/public/WebURL.h"

using WebKit::WebDocument;
using WebKit::WebElement;
using WebKit::WebFrame;
using WebKit::WebNode;
using WebKit::WebRange;
using WebKit::WebString;
using WebKit::WebURL;


CefDOMDocumentImpl::CefDOMDocumentImpl(CefBrowserImpl* browser,
                                       WebFrame* frame)
    : browser_(browser), frame_(frame)
{
  const WebDocument& document = frame_->document();
  DCHECK(!document.isNull());
}

CefDOMDocumentImpl::~CefDOMDocumentImpl()
{
  REQUIRE_UIT();

  // Verify that the Detach() method has been called.
  DCHECK(frame_ == NULL);
}

CefDOMDocumentImpl::Type CefDOMDocumentImpl::GetType()
{
  if (!VerifyContext())
    return DOM_DOCUMENT_TYPE_UNKNOWN;

  const WebDocument& document = frame_->document();
  if (document.isHTMLDocument())
    return DOM_DOCUMENT_TYPE_HTML;
  if (document.isXHTMLDocument())
    return DOM_DOCUMENT_TYPE_XHTML;
  if (document.isPluginDocument())
    return DOM_DOCUMENT_TYPE_PLUGIN;
  return DOM_DOCUMENT_TYPE_UNKNOWN;
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetDocument()
{
  const WebDocument& document = frame_->document();
  return GetOrCreateNode(document.document());
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetBody()
{
  const WebDocument& document = frame_->document();
  return GetOrCreateNode(document.body());
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetHead()
{
  WebDocument document = frame_->document();
  return GetOrCreateNode(document.head());
}

CefString CefDOMDocumentImpl::GetTitle()
{
  CefString str;
  if (!VerifyContext())
    return str;

  const WebDocument& document = frame_->document();
  const WebString& title = document.title();
  if (!title.isNull())
    str = title;

  return str;
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetElementById(const CefString& id)
{
  const WebDocument& document = frame_->document();
  return GetOrCreateNode(document.getElementById(string16(id)));
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetFocusedNode()
{
  const WebDocument& document = frame_->document();
  return GetOrCreateNode(document.focusedNode());
}

bool CefDOMDocumentImpl::HasSelection()
{
  if (!VerifyContext())
    return false;

  return frame_->hasSelection();
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetSelectionStartNode()
{
  if (!VerifyContext() || !frame_->hasSelection())
    return NULL;

  const WebRange& range = frame_->selectionRange();
  if (range.isNull())
    return NULL;

  int exceptionCode;
  return GetOrCreateNode(range.startContainer(exceptionCode));
}

int CefDOMDocumentImpl::GetSelectionStartOffset()
{
  if (!VerifyContext() || !frame_->hasSelection())
    return 0;

  const WebRange& range = frame_->selectionRange();
  if (range.isNull())
    return 0;

  return range.startOffset();
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetSelectionEndNode()
{
  if (!VerifyContext() || !frame_->hasSelection())
    return NULL;

  const WebRange& range = frame_->selectionRange();
  if (range.isNull())
    return NULL;

  int exceptionCode;
  return GetOrCreateNode(range.endContainer(exceptionCode));
}

int CefDOMDocumentImpl::GetSelectionEndOffset()
{
  if (!VerifyContext() || !frame_->hasSelection())
    return 0;

  const WebRange& range = frame_->selectionRange();
  if (range.isNull())
    return 0;

  return range.endOffset();
}

CefString CefDOMDocumentImpl::GetSelectionAsMarkup()
{
  CefString str;
  if (!VerifyContext() || !frame_->hasSelection())
    return str;

  const WebString& markup = frame_->selectionAsMarkup();
  if (!markup.isNull())
    str = markup;

  return str;
}

CefString CefDOMDocumentImpl::GetSelectionAsText()
{
  CefString str;
  if (!VerifyContext() || !frame_->hasSelection())
    return str;

  const WebString& text = frame_->selectionAsText();
  if (!text.isNull())
    str = text;

  return str;
}

CefString CefDOMDocumentImpl::GetBaseURL()
{
  CefString str;
  if (!VerifyContext())
    return str;
  
  const WebDocument& document = frame_->document();
  const WebURL& url = document.baseURL();
  if (!url.isNull()) {
    GURL gurl = url;
    str = gurl.spec();
  }

  return str;
}

CefString CefDOMDocumentImpl::GetCompleteURL(const CefString& partialURL)
{
  CefString str;
  if (!VerifyContext())
    return str;
  
  const WebDocument& document = frame_->document();
  const WebURL& url = document.completeURL(string16(partialURL));
  if (!url.isNull()) {
    GURL gurl = url;
    str = gurl.spec();
  }

  return str;
}

CefRefPtr<CefDOMNode> CefDOMDocumentImpl::GetOrCreateNode(
    const WebKit::WebNode& node)
{
  if (!VerifyContext())
    return NULL;

  // Nodes may potentially be null.
  if (node.isNull())
    return NULL;

  if (!node_map_.empty()) {
    // Locate the existing node, if any.
    NodeMap::const_iterator it = node_map_.find(node);
    if (it != node_map_.end())
      return it->second;
  }

  // Create the new node object.
  CefRefPtr<CefDOMNode> nodeImpl(new CefDOMNodeImpl(this, node));
  node_map_.insert(std::make_pair(node, nodeImpl));
  return nodeImpl;
}

void CefDOMDocumentImpl::RemoveNode(const WebKit::WebNode& node)
{
  if (!VerifyContext())
    return;

  if (!node_map_.empty()) {
    NodeMap::iterator it = node_map_.find(node);
    if (it != node_map_.end())
      node_map_.erase(it);
  }
}

void CefDOMDocumentImpl::Detach()
{
  if (!VerifyContext())
    return;

  // If you hit this assert it means that you are keeping references to node
  // objects beyond the valid scope.
  DCHECK(node_map_.empty());

  // If you hit this assert it means that you are keeping references to this
  // document object beyond the valid scope.
  DCHECK(GetRefCt() == 1);

  if (!node_map_.empty()) {
    NodeMap::const_iterator it = node_map_.begin();
    for (; it != node_map_.end(); ++it)
      static_cast<CefDOMNodeImpl*>(it->second)->Detach();
    node_map_.clear();
  }

  frame_ = NULL;
}

bool CefDOMDocumentImpl::VerifyContext()
{
  if(!CefThread::CurrentlyOn(CefThread::UI) || frame_ == NULL) {
    NOTREACHED();
    return false;
  }
  return true;
}