unique underline for links likely to open as image v1 PROPOSED

aoife cassidy: 1
 unique underline for links likely to open as image

 1 files changed, 15 insertions(+), 0 deletions(-)

[PATCH v1] unique underline for links likely to open as image Export this patch

---
prodded around on #senpai asking whether i should add this, got no
strong response so throwing this here for posterity.

the original idea was to have a nerd-fonts image button next to the
image but i decided against that and to use a different underline.
UnderlineDashed was picked as it's the most similar to UnderlineDotted,
but i could go with a solid underline if deemed more readable.

 ui/style.go | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/ui/style.go b/ui/style.go
index c563aca..03572a2 100644
--- a/ui/style.go
+++ b/ui/style.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"math/rand"
 	"net/url"
+	"path"
 	"regexp"
 	"strconv"
 	"strings"
@@ -114,6 +115,7 @@ func (s StyledString) ParseURLs() StyledString {
 		u := urls[i]
 		ub, ue := u[0], u[1]
 		link := s.string[u[0]:u[1]]
+		img := false
 		var params string
 		if link[0] == '#' {
 			if prev := lastRuneBefore(s.string, u[0]); !(prev == 0 || unicode.IsSpace(prev) || prev == '(' || prev == '[') {
@@ -129,6 +131,13 @@ func (s StyledString) ParseURLs() StyledString {
 				link = "https://" + link
 			}
 			params = fmt.Sprintf("id=_%010d", rand.Int31())
+			// roughly guess whether this link is an image or not based on file extension
+			if u, err := url.Parse(link); err == nil {
+				switch strings.ToLower(path.Ext(u.Path)) {
+				case ".jpg", ".jpeg", ".png", ".gif":
+					img = true
+				}
+			}
 		}
 		// find last style starting before or at url begin
 		for ; j < len(s.styles); j++ {
@@ -140,6 +149,9 @@ func (s StyledString) ParseURLs() StyledString {
 				// a style already starts at this position, edit it
 				st.Style.Hyperlink = link
 				st.Style.HyperlinkParams = params
+				if img {
+					st.Style.UnderlineStyle = vaxis.UnderlineDashed
+				}
 			}
 			lastStyle = st
 			styles = append(styles, st)
@@ -149,6 +161,9 @@ func (s StyledString) ParseURLs() StyledString {
 			st := lastStyle.Style
 			st.Hyperlink = link
 			st.HyperlinkParams = params
+			if img {
+				st.UnderlineStyle = vaxis.UnderlineDashed
+			}
 			styles = append(styles, rangedStyle{
 				Start: ub,
 				Style: st,

base-commit: f61411c169f0386d66fa3cedd9758a38eab2d68f
-- 
2.45.2