From 4a6d5da26c46e25d75107cfeb5987b42ea593e51 Mon Sep 17 00:00:00 2001
From: Adrian-George Bostan <adrg@epistack.com>
Date: Fri, 30 Nov 2018 18:45:48 +0200
Subject: [PATCH] Add default link style to paragraph

---
 pdf/creator/styled_paragraph.go | 32 +++++++++++++++++---------------
 pdf/creator/text_style.go       | 10 ++++++++++
 2 files changed, 27 insertions(+), 15 deletions(-)

diff --git a/pdf/creator/styled_paragraph.go b/pdf/creator/styled_paragraph.go
index bceab4c4..62aabafd 100644
--- a/pdf/creator/styled_paragraph.go
+++ b/pdf/creator/styled_paragraph.go
@@ -26,6 +26,9 @@ type StyledParagraph struct {
 	// Style used for the paragraph for spacing and offsets.
 	defaultStyle TextStyle
 
+	// Style used for the paragraph link annotations.
+	defaultLinkStyle TextStyle
+
 	// Text alignment: Align left/right/center/justify.
 	alignment TextAlignment
 
@@ -68,20 +71,19 @@ type StyledParagraph struct {
 // newStyledParagraph creates a new styled paragraph.
 func newStyledParagraph(style TextStyle) *StyledParagraph {
 	// TODO: Can we wrap intellectually, only if given width is known?
-	p := &StyledParagraph{
-		chunks:       []*TextChunk{},
-		defaultStyle: style,
-		lineHeight:   1.0,
-		alignment:    TextAlignmentLeft,
-		enableWrap:   true,
-		defaultWrap:  true,
-		angle:        0,
-		scaleX:       1,
-		scaleY:       1,
-		positioning:  positionRelative,
+	return &StyledParagraph{
+		chunks:           []*TextChunk{},
+		defaultStyle:     style,
+		defaultLinkStyle: newLinkStyle(style.Font),
+		lineHeight:       1.0,
+		alignment:        TextAlignmentLeft,
+		enableWrap:       true,
+		defaultWrap:      true,
+		angle:            0,
+		scaleX:           1,
+		scaleY:           1,
+		positioning:      positionRelative,
 	}
-
-	return p
 }
 
 // Append adds a new text chunk to the paragraph.
@@ -108,7 +110,7 @@ func (p *StyledParagraph) Insert(index uint, text string) *TextChunk {
 // The text parameter represents the text that is displayed and the url
 // parameter sets the destionation of the link.
 func (p *StyledParagraph) AddExternalLink(text, url string) *TextChunk {
-	chunk := newTextChunk(text, p.defaultStyle)
+	chunk := newTextChunk(text, p.defaultLinkStyle)
 	chunk.annotation = newExternalLinkAnnotation(url)
 	return p.appendChunk(chunk)
 }
@@ -120,7 +122,7 @@ func (p *StyledParagraph) AddExternalLink(text, url string) *TextChunk {
 // The zoom of the destination page is controlled with the zoom
 // parameter. Pass in 0 to keep the current zoom value.
 func (p *StyledParagraph) AddInternalLink(text string, page int64, x, y, zoom float64) *TextChunk {
-	chunk := newTextChunk(text, p.defaultStyle)
+	chunk := newTextChunk(text, p.defaultLinkStyle)
 	chunk.annotation = newInternalLinkAnnotation(page-1, x, y, zoom)
 	return p.appendChunk(chunk)
 }
diff --git a/pdf/creator/text_style.go b/pdf/creator/text_style.go
index 64532dcb..96a21c7f 100644
--- a/pdf/creator/text_style.go
+++ b/pdf/creator/text_style.go
@@ -29,3 +29,13 @@ func newTextStyle(font *model.PdfFont) TextStyle {
 		FontSize: 10,
 	}
 }
+
+// newLinkStyle creates a new text style object which can be
+// used for link annotations.
+func newLinkStyle(font *model.PdfFont) TextStyle {
+	return TextStyle{
+		Color:    ColorRGBFrom8bit(0, 0, 238),
+		Font:     font,
+		FontSize: 10,
+	}
+}