fpvectorial: html reader structural code

git-svn-id: trunk@45993 -

.gitattributes

@@ -1425,6 +1425,7 @@ components/fpvectorial/fpvectorialpkg.lpk svneol=native#text/plain
 components/fpvectorial/fpvectorialpkg.pas svneol=native#text/plain
 components/fpvectorial/fpvtocanvas.pas svneol=native#text/plain
 components/fpvectorial/fpvutils.pas svneol=native#text/plain
+components/fpvectorial/htmlvectorialreader.pas svneol=native#text/pascal
 components/fpvectorial/lasvectorialreader.pas svneol=native#text/plain
 components/fpvectorial/lazvectorialreader.pas svneol=native#text/plain
 components/fpvectorial/mathmlvectorialreader.pas svneol=native#text/plain

components/fpvectorial/fpvectorial.pas

@@ -54,7 +54,7 @@ type
     { Formula formats }
     vfMathML,
     { Text Document formats }
-    vfODT, vfDOCX,
+    vfODT, vfDOCX, vfHTML,
     { Raster Image formats }
     vfRAW
     );
@@ -89,6 +89,7 @@ const
   STR_ODG_EXTENSION = '.odg';
   STR_ODT_EXTENSION = '.odt';
   STR_DOCX_EXTENSION = '.docx';
+  STR_HTML_EXTENSION = '.html';
 
   STR_FPVECTORIAL_TEXT_HEIGHT_SAMPLE = 'Ćą';
 
@@ -6613,6 +6614,7 @@ begin
   else if AnsiCompareText(lExt, STR_MATHML_EXTENSION) = 0 then Result := vfMathML
   else if AnsiCompareText(lExt, STR_ODG_EXTENSION) = 0 then Result := vfODG
   else if AnsiCompareText(lExt, STR_DOCX_EXTENSION) = 0 then Result := vfDOCX
+  else if AnsiCompareText(lExt, STR_HTML_EXTENSION) = 0 then Result := vfHTML
   else
     raise Exception.Create('TvVectorialDocument.GetFormatFromExtension: The extension (' + lExt + ') doesn''t match any supported formats.');
 end;

components/fpvectorial/fpvectorialpkg.lpk

@@ -1,4 +1,4 @@
-<?xml version="1.0"?>
+<?xml version="1.0" encoding="UTF-8"?>
 <CONFIG>
   <Package Version="4">
     <Name Value="fpvectorialpkg"/>
@@ -12,7 +12,7 @@
         <CompilerPath Value="$(CompPath)"/>
       </Other>
     </CompilerOptions>
-    <Files Count="20">
+    <Files Count="21">
       <Item1>
         <Filename Value="fpvectorial.pas"/>
         <UnitName Value="fpvectorial"/>
@@ -93,6 +93,10 @@
         <Filename Value="docxvectorialwriter.pas"/>
         <UnitName Value="docxvectorialwriter"/>
       </Item20>
+      <Item21>
+        <Filename Value="htmlvectorialreader.pas"/>
+        <UnitName Value="htmlvectorialreader"/>
+      </Item21>
     </Files>
     <Type Value="RunAndDesignTime"/>
     <RequiredPkgs Count="2">

components/fpvectorial/fpvectorialpkg.pas

@@ -13,7 +13,7 @@ uses
   lazvectorialreader, mathmlvectorialreader, odgvectorialreader, 
   rawvectorialreadwrite, svgvectorialreader, svgvectorialwriter, 
   svgzvectorialreader, odtvectorialwriter, docxvectorialwriter, 
-  LazarusPackageIntf;
+  htmlvectorialreader, LazarusPackageIntf;
 
 implementation
 

components/fpvectorial/htmlvectorialreader.pas

@@ -0,0 +1,176 @@
+{
+Reads a HTML Document
+
+License: The same modified LGPL as the Free Pascal RTL
+         See the file COPYING.modifiedLGPL for more details
+
+AUTHORS: Felipe Monteiro de Carvalho
+}
+unit htmlvectorialreader;
+
+{$mode objfpc}{$H+}
+
+interface
+
+uses
+  Classes, SysUtils, math, contnrs,
+  fpimage, fpcanvas, laz2_xmlread, laz2_dom, fgl,
+  // image data formats
+  fpreadpng,
+  // HTML can contain SVG
+  svgvectorialreader,
+  fpvectorial, fpvutils, lazutf8, TypInfo;
+
+type
+  { TvHTMLVectorialReader }
+
+  TvHTMLVectorialReader = class(TvCustomVectorialReader)
+  private
+    FPointSeparator, FCommaSeparator: TFormatSettings;
+    //
+    function ReadEntityFromNode(ANode: TDOMNode; AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+    function ReadHeaderFromNode(ANode: TDOMNode; AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+    function ReadParagraphFromNode(ANode: TDOMNode; AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+    function ReadSVGFromNode(ANode: TDOMNode; AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+  public
+    { General reading methods }
+    constructor Create; override;
+    Destructor Destroy; override;
+    procedure ReadFromStrings(AStrings: TStrings; AData: TvVectorialDocument); override;
+    procedure ReadFromXML(Doc: TXMLDocument; AData: TvVectorialDocument);
+  end;
+
+implementation
+
+const
+  // SVG requires hardcoding a DPI value
+
+  // The Opera Browser and Inkscape use 90 DPI, so we follow that
+
+  // 1 Inch = 25.4 milimiters
+  // 90 inches per pixel = (1 / 90) * 25.4 = 0.2822
+  // FLOAT_MILIMETERS_PER_PIXEL = 0.3528; // DPI 72 = 1 / 72 inches per pixel
+
+  FLOAT_MILIMETERS_PER_PIXEL = 5*0.2822; // DPI 90 = 1 / 90 inches per pixel => Actually I changed the value by this factor! Because otherwise it looks ugly!
+  FLOAT_PIXELS_PER_MILIMETER = 1 / FLOAT_MILIMETERS_PER_PIXEL; // DPI 90 = 1 / 90 inches per pixel
+
+{ TvHTMLVectorialReader }
+
+function TvHTMLVectorialReader.ReadEntityFromNode(ANode: TDOMNode;
+  AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+var
+  lEntityName: DOMString;
+begin
+  Result := nil;
+  lEntityName := LowerCase(ANode.NodeName);
+  case lEntityName of
+    'h1', 'h2', 'h3', 'h4', 'h5', 'h6': Result := ReadHeaderFromNode(ANode, AData, ADoc);
+    'p': Result := ReadParagraphFromNode(ANode, AData, ADoc);
+    'svg': Result := ReadSVGFromNode(ANode, AData, ADoc);
+  end;
+end;
+
+function TvHTMLVectorialReader.ReadHeaderFromNode(ANode: TDOMNode;
+  AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+begin
+end;
+
+function TvHTMLVectorialReader.ReadParagraphFromNode(ANode: TDOMNode;
+  AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+begin
+end;
+
+function TvHTMLVectorialReader.ReadSVGFromNode(ANode: TDOMNode;
+  AData: TvVectorialPage; ADoc: TvVectorialDocument): TvEntity;
+begin
+end;
+
+constructor TvHTMLVectorialReader.Create;
+begin
+  inherited Create;
+
+  FPointSeparator := DefaultFormatSettings;
+  FPointSeparator.DecimalSeparator := '.';
+  FPointSeparator.ThousandSeparator := '#';// disable the thousand separator
+end;
+
+destructor TvHTMLVectorialReader.Destroy;
+begin
+  inherited Destroy;
+end;
+
+procedure TvHTMLVectorialReader.ReadFromStrings(AStrings: TStrings;
+  AData: TvVectorialDocument);
+var
+  Doc: TXMLDocument = nil;
+  lStream: TMemoryStream;
+  lTmp: String;
+begin
+  lStream := TMemoryStream.Create();
+  try
+    // Remove the <!DOCTYPE line
+    if Pos('<!DOCTYPE', AStrings.Strings[0]) <> 0 then
+      AStrings.Delete(0);
+    // Create a header
+    AStrings.Insert(0, '<?xml version="1.0"?>');
+    lTmp := AStrings.Text;
+    // Flush it back to a stream
+    AStrings.SaveToStream(lStream);
+    lStream.Position := 0;
+    // HTML is not XML, but might be compatible enough... a dedicated reader will be complex, but eventually necessary
+    ReadXMLFile(Doc, lStream);
+    lStream.Free; // Release as soon as unnecessary
+    lStream := nil;
+    //
+    ReadFromXML(Doc, AData);
+  finally
+    Doc.Free;
+    lStream.Free;
+  end;
+end;
+
+procedure TvHTMLVectorialReader.ReadFromXML(Doc: TXMLDocument;
+  AData: TvVectorialDocument);
+var
+  lCurNode: TDOMNode;
+  lPage: TvVectorialPage;
+  lNodeName, lNodeValue: DOMString;
+  ANode: TDOMElement;
+  i: Integer;
+  lCurEntity: TvEntity;
+  lViewBox: TDoubleArray;
+  lStr: string;
+  lDocNeedsSizeAutoDetection: Boolean = True;
+  lx, ly, lx2, ly2: Double;
+begin
+  {ANode := Doc.DocumentElement;
+  for i := 0 to ANode.Attributes.Length - 1 do
+  begin
+    lNodeName := ANode.Attributes.Item[i].NodeName;
+    lNodeValue := ANode.Attributes.Item[i].NodeValue;
+  end;}
+
+  // ----------------
+  // Now process the elements
+  // ----------------
+  lCurNode := Doc.DocumentElement.FirstChild;
+  lPage := AData.AddPage();
+  //lPage.Width := AData.Width;
+  //lPage.Height := AData.Height;
+  while Assigned(lCurNode) do
+  begin
+    lNodeName := lCurNode.NodeName;
+    lCurEntity := ReadEntityFromNode(lCurNode, lPage, AData);
+    if lCurEntity <> nil then
+      lPage.AddEntity(lCurEntity);
+
+    lCurNode := lCurNode.NextSibling;
+  end;
+end;
+
+initialization
+
+  RegisterVectorialReader(TvHTMLVectorialReader, vfHTML);
+
+end.
+

components/fpvectorial/svgvectorialreader.pas

@@ -2889,7 +2889,7 @@ end;
 procedure TvSVGVectorialReader.ReadFromStream(AStream: TStream;
   AData: TvVectorialDocument);
 var
-  Doc: TXMLDocument;
+  Doc: TXMLDocument = nil;
 begin
   try
     // Read in xml file from the stream