Add document outline support

@@ -22,7 +22,7 @@ import 'package:pdf/pdf.dart';
 import 'package:pdf/widgets.dart' as pw;
 
 Future<Uint8List> generateDocument(PdfPageFormat format) async {
-  final pw.Document doc = pw.Document();
+  final pw.Document doc = pw.Document(pageMode: PdfPageMode.outlines);
 
   doc.addPage(pw.MultiPage(
       pageFormat:
@@ -57,6 +57,7 @@ Future<Uint8List> generateDocument(PdfPageFormat format) async {
       build: (pw.Context context) => <pw.Widget>[
             pw.Header(
                 level: 0,
+                title: 'Portable Document Format',
                 child: pw.Row(
                     mainAxisAlignment: pw.MainAxisAlignment.spaceBetween,
                     children: <pw.Widget>[

@@ -4,6 +4,7 @@
 
 - Implement different border radius on all corners
 - Add AcroForm widgets
+- Add document outline support
 
 ## 1.12.0
 

@@ -207,20 +207,27 @@ class PdfSecString extends PdfString {
       [PdfStringFormat format = PdfStringFormat.binary])
       : super(value, format);
 
-  factory PdfSecString.fromString(PdfObject object, String value) {
+  factory PdfSecString.fromString(
+    PdfObject object,
+    String value, [
+    PdfStringFormat format = PdfStringFormat.litteral,
+  ]) {
     return PdfSecString(
       object,
       PdfString._string(value),
-      PdfStringFormat.litteral,
+      format,
     );
   }
 
-  factory PdfSecString.fromStream(PdfObject object, PdfStream value,
-      [PdfStringFormat format = PdfStringFormat.litteral]) {
+  factory PdfSecString.fromStream(
+    PdfObject object,
+    PdfStream value, [
+    PdfStringFormat format = PdfStringFormat.litteral,
+  ]) {
     return PdfSecString(
       object,
       value.output(),
-      PdfStringFormat.litteral,
+      format,
     );
   }
 

@@ -14,13 +14,15 @@
  * limitations under the License.
  */
 
+// ignore_for_file: omit_local_variable_types
+
 part of pdf;
 
 class PdfNames extends PdfObject {
   /// This constructs a Pdf Name object
   PdfNames(PdfDocument pdfDocument) : super(pdfDocument);
 
-  final PdfArray _dests = PdfArray();
+  final Map<String, PdfDataType> _dests = <String, PdfDataType>{};
 
   void addDest(
     String name,
@@ -32,8 +34,7 @@ class PdfNames extends PdfObject {
     assert(page.pdfDocument == pdfDocument);
     assert(name != null);
 
-    _dests.add(PdfSecString.fromString(this, name));
-    _dests.add(PdfDict(<String, PdfDataType>{
+    _dests[name] = PdfDict(<String, PdfDataType>{
       '/D': PdfArray(<PdfDataType>[
         page.ref(),
         const PdfName('/XYZ'),
@@ -41,13 +42,32 @@ class PdfNames extends PdfObject {
         if (posY == null) const PdfNull() else PdfNum(posY),
         if (posZ == null) const PdfNull() else PdfNum(posZ),
       ]),
-    }));
+    });
   }
 
   @override
   void _prepare() {
     super._prepare();
 
-    params['/Dests'] = PdfDict(<String, PdfDataType>{'/Names': _dests});
+    if (_dests.isEmpty) {
+      return;
+    }
+
+    final PdfArray dests = PdfArray();
+
+    final List<String> keys = _dests.keys.toList()..sort();
+
+    for (String name in keys) {
+      dests.add(PdfSecString.fromString(this, name));
+      dests.add(_dests[name]);
+    }
+
+    params['/Dests'] = PdfDict(<String, PdfDataType>{
+      '/Names': dests,
+      '/Limits': PdfArray(<PdfDataType>[
+        PdfSecString.fromString(this, keys.first),
+        PdfSecString.fromString(this, keys.last),
+      ])
+    });
   }
 }

@@ -26,15 +26,36 @@ enum PdfOutlineMode {
   fitrect
 }
 
+enum PdfOutlineStyle {
+  /// Normal
+  normal,
+
+  /// Italic
+  italic,
+
+  // Bold
+  bold,
+
+  /// Italic and Bold
+  italicBold,
+}
+
 class PdfOutline extends PdfObject {
   /// Constructs a Pdf Outline object. When selected, the specified region
   /// is displayed.
-  ///
-  /// @param title Title of the outline
-  /// @param dest The destination page
-  /// @param rect coordinate
-  PdfOutline(PdfDocument pdfDocument, {this.title, this.dest, this.rect})
-      : super(pdfDocument, '/Outlines');
+  PdfOutline(
+    PdfDocument pdfDocument, {
+    this.title,
+    this.dest,
+    this.rect,
+    this.anchor,
+    this.color,
+    this.destMode = PdfOutlineMode.fitpage,
+    this.style = PdfOutlineStyle.normal,
+  })  : assert(anchor == null || (dest == null && rect == null)),
+        assert(destMode != null),
+        assert(style != null),
+        super(pdfDocument);
 
   /// This holds any outlines below us
   List<PdfOutline> outlines = <PdfOutline>[];
@@ -51,33 +72,25 @@ class PdfOutline extends PdfObject {
   /// The region on the destination page
   final PdfRect rect;
 
+  /// Named destination
+  final String anchor;
+
+  /// Color of the outline text
+  final PdfColor color;
+
   /// How the destination is handled
-  PdfOutlineMode destMode = PdfOutlineMode.fitpage;
+  final PdfOutlineMode destMode;
+
+  /// How to display the outline text
+  final PdfOutlineStyle style;
+
+  int effectiveLevel;
 
   /// This method creates an outline, and attaches it to this one.
   /// When the outline is selected, the supplied region is displayed.
-  ///
-  /// Note: the coordinates are in User space. They are converted to User
-  /// space.
-  ///
-  /// This allows you to have an outline for say a Chapter,
-  /// then under the chapter, one for each section. You are not really
-  /// limited on how deep you go, but it's best not to go below say 6 levels,
-  /// for the reader's sake.
-  ///
-  /// @param title Title of the outline
-  /// @param dest The destination page
-  /// @param x coordinate of region in User space
-  /// @param y coordinate of region in User space
-  /// @param w width of region in User space
-  /// @param h height of region in User space
-  /// @return [PdfOutline] object created, for creating sub-outlines
-  PdfOutline add({String title, PdfPage dest, PdfRect rect}) {
-    final PdfOutline outline =
-        PdfOutline(pdfDocument, title: title, dest: dest, rect: rect);
-    // Tell the outline of ourselves
+  void add(PdfOutline outline) {
     outline.parent = this;
-    return outline;
+    outlines.add(outline);
   }
 
   /// @param os OutputStream to send the object to
@@ -88,20 +101,33 @@ class PdfOutline extends PdfObject {
     // These are for kids only
     if (parent != null) {
       params['/Title'] = PdfSecString.fromString(this, title);
-      final PdfArray dests = PdfArray();
-      dests.add(dest.ref());
 
-      if (destMode == PdfOutlineMode.fitpage) {
-        dests.add(const PdfName('/Fit'));
+      if (color != null) {
+        params['/C'] = PdfColorType(color);
+      }
+
+      if (style != PdfOutlineStyle.normal) {
+        params['/F'] = PdfNum(style.index);
+      }
+
+      if (anchor != null) {
+        params['/Dest'] = PdfSecString.fromString(this, anchor);
       } else {
-        dests.add(const PdfName('/FitR'));
-        dests.add(PdfNum(rect.left));
-        dests.add(PdfNum(rect.bottom));
-        dests.add(PdfNum(rect.right));
-        dests.add(PdfNum(rect.top));
+        final PdfArray dests = PdfArray();
+        dests.add(dest.ref());
+
+        if (destMode == PdfOutlineMode.fitpage) {
+          dests.add(const PdfName('/Fit'));
+        } else {
+          dests.add(const PdfName('/FitR'));
+          dests.add(PdfNum(rect.left));
+          dests.add(PdfNum(rect.bottom));
+          dests.add(PdfNum(rect.right));
+          dests.add(PdfNum(rect.top));
+        }
+        params['/Dest'] = dests;
       }
       params['/Parent'] = parent.ref();
-      params['/Dest'] = dests;
 
       // were a descendent, so by default we are closed. Find out how many
       // entries are below us

@@ -19,22 +19,38 @@
 part of widget;
 
 class Anchor extends SingleChildWidget {
-  Anchor({Widget child, @required this.name, this.description})
-      : assert(name != null),
+  Anchor({
+    Widget child,
+    @required this.name,
+    this.description,
+    this.zoom,
+    this.setX = false,
+  })  : assert(name != null),
+        assert(setX != null),
         super(child: child);
 
   final String name;
 
   final String description;
 
+  final double zoom;
+
+  final bool setX;
+
   @override
   void paint(Context context) {
     super.paint(context);
     paintChild(context);
 
     final Matrix4 mat = context.canvas.getTransform();
-    final Vector3 lt = mat.transform3(Vector3(box.left, box.bottom, 0));
-    context.document.pdfNames.addDest(name, context.page, posY: lt.y);
+    final Vector3 lt = mat.transform3(Vector3(box.left, box.top, 0));
+    context.document.pdfNames.addDest(
+      name,
+      context.page,
+      posX: setX ? lt.x : null,
+      posY: lt.y,
+      posZ: zoom,
+    );
 
     if (description != null) {
       final Vector3 rb = mat.transform3(Vector3(box.right, box.top, 0));
@@ -307,3 +323,74 @@ class TextField extends Annotation {
               textStyle: textStyle,
             ));
 }
+
+class Outline extends Anchor {
+  Outline({
+    Widget child,
+    @required String name,
+    @required this.title,
+    this.level = 0,
+    this.color,
+    this.style = PdfOutlineStyle.normal,
+  })  : assert(title != null),
+        assert(level != null && level >= 0),
+        assert(style != null),
+        super(child: child, name: name, setX: true);
+
+  final String title;
+
+  final int level;
+
+  final PdfColor color;
+
+  final PdfOutlineStyle style;
+
+  PdfOutline _outline;
+
+  @override
+  void layout(Context context, BoxConstraints constraints,
+      {bool parentUsesSize = false}) {
+    super.layout(context, constraints, parentUsesSize: parentUsesSize);
+    _buildOutline(context);
+  }
+
+  @override
+  void debugPaint(Context context) {
+    context.canvas
+      ..setFillColor(PdfColors.pink100)
+      ..drawRect(box.x, box.y, box.width, box.height)
+      ..fillPath();
+  }
+
+  void _buildOutline(Context context) {
+    if (_outline != null) {
+      return;
+    }
+
+    _outline = PdfOutline(
+      context.document,
+      title: title,
+      anchor: name,
+      color: color,
+      style: style,
+    );
+
+    PdfOutline parent = context.document.outline;
+    int l = level;
+
+    while (l > 0) {
+      if (parent.effectiveLevel == l) {
+        break;
+      }
+
+      if (parent.outlines.isEmpty) {
+        parent.effectiveLevel = level;
+        break;
+      }
+      parent = parent.outlines.last;
+      l--;
+    }
+
+    parent.add(_outline);
+  }
+}

@@ -19,15 +19,23 @@
 part of widget;
 
 class Header extends StatelessWidget {
-  Header(
-      {this.level = 1,
-      this.text,
-      this.child,
-      this.decoration,
-      this.margin,
-      this.padding,
-      this.textStyle})
-      : assert(level >= 0 && level <= 5);
+  Header({
+    this.level = 1,
+    this.text,
+    this.child,
+    this.decoration,
+    this.margin,
+    this.padding,
+    this.textStyle,
+    String title,
+    this.outlineColor,
+    this.outlineStyle = PdfOutlineStyle.normal,
+  })  : assert(level != null, level >= 0 && level <= 5),
+        assert(text != null || child != null),
+        assert(outlineStyle != null),
+        title = title ?? text;
+
+  final String title;
 
   final String text;
 
@@ -43,6 +51,10 @@ class Header extends StatelessWidget {
 
   final TextStyle textStyle;
 
+  final PdfColor outlineColor;
+
+  final PdfOutlineStyle outlineStyle;
+
   @override
   Widget build(Context context) {
     BoxDecoration _decoration = decoration;
@@ -85,13 +97,27 @@ class Header extends StatelessWidget {
         _textStyle ??= Theme.of(context).header5;
         break;
     }
-    return Container(
+
+    final Widget container = Container(
       alignment: Alignment.topLeft,
       margin: _margin,
       padding: _padding,
       decoration: _decoration,
       child: child ?? Text(text, style: _textStyle),
     );
+
+    if (title == null) {
+      return container;
+    }
+
+    return Outline(
+      name: text.hashCode.toString(),
+      title: title,
+      child: container,
+      level: level,
+      color: outlineColor,
+      style: outlineStyle,
+    );
   }
 }
 

@@ -40,6 +40,7 @@ import 'widget_form_test.dart' as widget_form;
 import 'widget_grid_view_test.dart' as widget_grid_view;
 import 'widget_multipage_test.dart' as widget_multipage;
 import 'widget_opacity_test.dart' as widget_opacity;
+import 'widget_outline_test.dart' as widget_outline;
 import 'widget_partitions_test.dart' as widget_partitions;
 import 'widget_table_test.dart' as widget_table;
 import 'widget_test.dart' as widget;
@@ -73,6 +74,7 @@ void main() {
   widget_grid_view.main();
   widget_multipage.main();
   widget_opacity.main();
+  widget_outline.main();
   widget_partitions.main();
   widget_table.main();
   widget_text.main();

@@ -175,14 +175,14 @@ Document pdf;
 void main() {
   setUpAll(() {
     Document.debug = true;
-    pdf = Document();
+    pdf = Document(pageMode: PdfPageMode.outlines);
   });
 
   test('Pdf Colors', () {
     pdf.addPage(MultiPage(
         pageFormat: PdfPageFormat.standard,
         build: (Context context) => <Widget>[
-              Header(text: 'Red'),
+              Header(text: 'Red', outlineColor: PdfColors.red),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -207,7 +207,7 @@ void main() {
                     Color(PdfColors.redAccent700, 'Red', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Pink'),
+              Header(text: 'Pink', outlineColor: PdfColors.pink),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -232,7 +232,7 @@ void main() {
                     Color(PdfColors.pinkAccent700, 'Pink', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Purple'),
+              Header(text: 'Purple', outlineColor: PdfColors.purple),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -257,7 +257,7 @@ void main() {
                     Color(PdfColors.purpleAccent700, 'Purple', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Deep Purple'),
+              Header(text: 'Deep Purple', outlineColor: PdfColors.deepPurple),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -286,7 +286,7 @@ void main() {
                         'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Indigo'),
+              Header(text: 'Indigo', outlineColor: PdfColors.indigo),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -311,7 +311,7 @@ void main() {
                     Color(PdfColors.indigoAccent700, 'Indigo', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Blue'),
+              Header(text: 'Blue', outlineColor: PdfColors.blue),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -336,7 +336,7 @@ void main() {
                     Color(PdfColors.blueAccent700, 'Blue', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Light Blue'),
+              Header(text: 'Light Blue', outlineColor: PdfColors.lightBlue),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -365,7 +365,7 @@ void main() {
                         'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Cyan'),
+              Header(text: 'Cyan', outlineColor: PdfColors.cyan),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -390,7 +390,7 @@ void main() {
                     Color(PdfColors.cyanAccent700, 'Cyan', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Teal'),
+              Header(text: 'Teal', outlineColor: PdfColors.teal),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -415,7 +415,7 @@ void main() {
                     Color(PdfColors.tealAccent700, 'Teal', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Green'),
+              Header(text: 'Green', outlineColor: PdfColors.green),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -440,7 +440,7 @@ void main() {
                     Color(PdfColors.greenAccent700, 'Green', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Light Green'),
+              Header(text: 'Light Green', outlineColor: PdfColors.lightGreen),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -469,7 +469,7 @@ void main() {
                         'Accent700'),
                   ]),
               NewPage(),
-              Header(text: 'Lime'),
+              Header(text: 'Lime', outlineColor: PdfColors.lime),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -494,7 +494,7 @@ void main() {
                     Color(PdfColors.limeAccent700, 'Lime', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Yellow'),
+              Header(text: 'Yellow', outlineColor: PdfColors.yellow),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -519,7 +519,7 @@ void main() {
                     Color(PdfColors.yellowAccent700, 'Yellow', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Amber'),
+              Header(text: 'Amber', outlineColor: PdfColors.amber),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -544,7 +544,7 @@ void main() {
                     Color(PdfColors.amberAccent700, 'Amber', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Orange'),
+              Header(text: 'Orange', outlineColor: PdfColors.orange),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -569,7 +569,7 @@ void main() {
                     Color(PdfColors.orangeAccent700, 'Orange', 'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Deep Orange'),
+              Header(text: 'Deep Orange', outlineColor: PdfColors.deepOrange),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -598,7 +598,7 @@ void main() {
                         'Accent 700'),
                   ]),
               NewPage(),
-              Header(text: 'Brown'),
+              Header(text: 'Brown', outlineColor: PdfColors.brown),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -619,7 +619,7 @@ void main() {
                     Color(PdfColors.brown900, 'Brown', '900'),
                   ]),
               NewPage(),
-              Header(text: 'Blue Grey'),
+              Header(text: 'Blue Grey', outlineColor: PdfColors.blueGrey),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -640,7 +640,7 @@ void main() {
                     Color(PdfColors.blueGrey900, 'Blue Grey', '900'),
                   ]),
               NewPage(),
-              Header(text: 'Grey'),
+              Header(text: 'Grey', outlineColor: PdfColors.grey),
               GridView(
                   crossAxisCount: 4,
                   direction: Axis.vertical,
@@ -677,7 +677,7 @@ void main() {
       pdf.addPage(Page(
           build: (Context context) => Column(
                 children: <Widget>[
-                  Header(text: name),
+                  Header(text: name, outlineStyle: PdfOutlineStyle.italic),
                   SizedBox(
                     height: context.page.pageFormat.availableWidth,
                     child: ColorWheel(

+/*
+ * Copyright (C) 2017, David PHAM-VAN <dev.nfet.net@gmail.com>
+ *
+ * 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.
+ */
+
+// ignore_for_file: omit_local_variable_types
+
+import 'dart:io';
+import 'dart:math';
+
+import 'package:pdf/pdf.dart';
+import 'package:pdf/widgets.dart';
+import 'package:test/test.dart';
+
+Document pdf;
+
+final LoremText lorem = LoremText(random: Random(42));
+
+Iterable<Widget> level(int i) sync* {
+  final String text = lorem.sentence(5);
+  int p = 0;
+  PdfColor color;
+  PdfOutlineStyle style = PdfOutlineStyle.normal;
+
+  if (i >= 3 && i <= 6) {
+    p++;
+  }
+
+  if (i >= 5 && i <= 6) {
+    p++;
+  }
+
+  if (i == 15) {
+    p = 10;
+    color = PdfColors.amber;
+    style = PdfOutlineStyle.bold;
+  }
+
+  if (i == 17) {
+    color = PdfColors.red;
+    style = PdfOutlineStyle.italic;
+  }
+
+  if (i == 18) {
+    color = PdfColors.blue;
+    style = PdfOutlineStyle.italicBold;
+  }
+
+  yield Outline(
+    child: Text(text),
+    name: 'anchor$i',
+    title: text,
+    level: p,
+    color: color,
+    style: style,
+  );
+
+  yield SizedBox(height: 300);
+}
+
+void main() {
+  setUpAll(() {
+    Document.debug = true;
+    pdf = Document(pageMode: PdfPageMode.outlines);
+  });
+
+  test('Outline Widget', () {
+    pdf.addPage(
+      MultiPage(
+        build: (Context context) => <Widget>[
+          for (int i = 0; i < 20; i++) ...level(i),
+        ],
+      ),
+    );
+  });
+
+  tearDownAll(() {
+    final File file = File('widgets-outline.pdf');
+    file.writeAsBytesSync(pdf.save());
+  });
+}