Infrastructure for simple internal hyperlink handling

tools/tui/render_lines.go

@@ -0,0 +1,120 @@
+package tui
+
+import (
+	"fmt"
+	"regexp"
+	"strings"
+	"sync"
+
+	"kitty/tools/tui/loop"
+	"kitty/tools/utils/style"
+	"kitty/tools/wcswidth"
+)
+
+var _ = fmt.Print
+
+const KittyInternalHyperlinkProtocol = "kitty-ih"
+
+func InternalHyperlink(text, id string) string {
+	return fmt.Sprintf("\x1b]8;;%s:%s\x1b\\%s\x1b]8;;\x1b\\", KittyInternalHyperlinkProtocol, id, text)
+}
+
+type RenderLines struct {
+	WrapOptions style.WrapOptions
+}
+
+var hyperlink_pat = sync.OnceValue(func() *regexp.Regexp {
+	return regexp.MustCompile("\x1b]8;([^;]*);.*?(\x1b\\\\|\a)")
+})
+
+// Render lines in the specified rectangle. If width > 0 then lines are wrapped
+// to fit in the width. A string containing rendered lines with escape codes to
+// move cursor is returned. Any internal hyperlinks are added to the
+// MouseState.
+func (r RenderLines) InRectangle(
+	lines []string, start_x, start_y, width, height int, mouse_state *MouseState,
+) (all_rendered bool, final_y int, ans string) {
+	end_y := start_y + height - 1
+	if end_y < start_y {
+		return len(lines) == 0, start_y, ""
+	}
+	x, y := start_x, start_y
+	buf := strings.Builder{}
+	buf.Grow(len(lines) * max(1, width) * 3)
+	move_cursor := func(x, y int) { buf.WriteString(fmt.Sprintf(loop.MoveCursorToTemplate, y+1, x+1)) }
+	var hyperlink_state struct {
+		action           string
+		start_x, start_y int
+	}
+
+	start_hyperlink := func(action string) {
+		hyperlink_state.action = action
+		hyperlink_state.start_x, hyperlink_state.start_y = x, y
+	}
+
+	add_chunk := func(text string) {
+		if text != "" {
+			buf.WriteString(text)
+			x += wcswidth.Stringwidth(text)
+		}
+	}
+
+	commit_hyperlink := func() {
+		mouse_state.AddCellRegion(hyperlink_state.action, hyperlink_state.start_x, hyperlink_state.start_y, x, y)
+		hyperlink_state.action = ``
+	}
+
+	add_hyperlink := func(id, url string) {
+		is_closer := id == "" && url == ""
+		if is_closer {
+			if hyperlink_state.action != "" {
+				commit_hyperlink()
+			} else {
+				buf.WriteString("\x1b]8;;\x1b\\")
+			}
+		} else {
+			if hyperlink_state.action != "" {
+				commit_hyperlink()
+			}
+			if strings.HasPrefix(url, KittyInternalHyperlinkProtocol+":") {
+				start_hyperlink(url[len(KittyInternalHyperlinkProtocol)+1:])
+			} else {
+				buf.WriteString(fmt.Sprintf("\x1b]8;%s;%s\x1b\\", id, url))
+			}
+		}
+
+	}
+
+	add_line := func(line string) {
+		x = start_x
+		indices := hyperlink_pat().FindAllStringSubmatchIndex(line, -1)
+		start := 0
+		for _, index := range indices {
+			full_hyperlink_start, full_hyperlink_end := index[0], index[1]
+			add_chunk(line[start:full_hyperlink_start])
+			start = full_hyperlink_end
+			add_hyperlink(line[index[2]:index[3]], line[index[4]:index[5]])
+		}
+		add_chunk(line[start:])
+	}
+
+	all_rendered = true
+	for _, line := range lines {
+		lines := []string{line}
+		if width > 0 {
+			lines = style.WrapTextAsLines(line, width, r.WrapOptions)
+		}
+		for _, line := range lines {
+			if y > end_y {
+				all_rendered = false
+				goto end
+			}
+			move_cursor(start_x, y)
+			add_line(line)
+			y += 1
+		}
+	}
+end:
+	commit_hyperlink()
+	return all_rendered, y, buf.String()
+}