prime8dev

project_markdown_render.go (4760B)

---

 package tui
 
 import "strings"
 
 // README rendering is synchronous and on demand: whenever the detail pane is
 // about to show the selected project (syncViewport: selection, tab switch,
 // resize, a README arriving), its README is rendered for the current width if
 // that width is not cached yet. Rendering takes a few milliseconds, and doing
 // it inline means the pane can never show the raw markdown while an async
 // render is in flight, or keep showing it because a render result was
 // dropped or landed for a width/README that was no longer current (what the
 // old async path did until something happened to re-render the pane).
 
 func (m portfolioModel) cachedProjectMarkdown(projectID string, width int) (string, bool) {
 	byWidth, ok := m.projectReadmeRender[projectID]
 	if !ok {
 		return "", false
 	}
 
 	rendered, ok := byWidth[width]
 	return rendered, ok
 }
 
 // maxCachedReadmeWidths bounds the per-project cache while a window is
 // being resized through many widths.
 const maxCachedReadmeWidths = 8
 
 func (m *portfolioModel) setCachedProjectMarkdown(projectID string, width int, rendered string) {
 	byWidth := m.projectReadmeRender[projectID]
 	if byWidth == nil || len(byWidth) >= maxCachedReadmeWidths {
 		byWidth = make(map[int]string)
 		m.projectReadmeRender[projectID] = byWidth
 	}
 
 	byWidth[width] = rendered
 }
 
 // ensureSelectedProjectMarkdown renders the selected project's README for the
 // current detail width when it is not cached. It reports whether it rendered.
 func (m *portfolioModel) ensureSelectedProjectMarkdown() bool {
 	if m.activeTab != tabProjects || m.projectReadmeRender == nil {
 		return false
 	}
 
 	project := m.selectedProject()
 	if project == nil {
 		return false
 	}
 
 	readme, ok := m.projectReadmes[project.ID]
 	if !ok || strings.TrimSpace(readme) == "" {
 		return false
 	}
 
 	width := m.projectMarkdownWidth()
 	if _, ok := m.cachedProjectMarkdown(project.ID, width); ok {
 		return false
 	}
 
 	patched := replaceFirstH1WithSourceLink(readme, project.Name, project.URL)
 	m.setCachedProjectMarkdown(project.ID, width, renderProjectMarkdown(patched, renderTagList(project.Tech), width))
 	return true
 }
 
 func renderProjectMarkdown(markdown string, techRow string, width int) string {
 	rendered := renderMarkdown(markdown, width)
 	if rendered == "" {
 		rendered = markdown
 	}
 	rendered = outdentRenderedBody(rendered)
 	if strings.TrimSpace(techRow) != "" {
 		rendered = insertTechRowBelowRenderedH1(rendered, techRow)
 	}
 	return rendered
 }
 
 func insertTechRowBelowRenderedH1(rendered string, techRow string) string {
 	if strings.TrimSpace(techRow) == "" {
 		return rendered
 	}
 
 	lines := strings.Split(rendered, "\n")
 	headIdx := -1
 	for i, line := range lines {
 		plain := strings.TrimSpace(ansiEscapeRE.ReplaceAllString(line, ""))
 		if plain != "" {
 			headIdx = i
 			break
 		}
 	}
 	if headIdx == -1 {
 		if strings.TrimSpace(rendered) == "" {
 			return techRow
 		}
 		return techRow + "\n\n" + rendered
 	}
 
 	insertAt := headingBlockEndIndex(lines, headIdx)
 
 	bodyStart := insertAt
 	for bodyStart < len(lines) && strings.TrimSpace(ansiEscapeRE.ReplaceAllString(lines[bodyStart], "")) == "" {
 		bodyStart++
 	}
 
 	header := strings.Join(lines[:insertAt], "\n")
 	if bodyStart >= len(lines) {
 		if strings.TrimSpace(header) == "" {
 			return techRow
 		}
 		return header + "\n" + techRow
 	}
 
 	body := strings.Join(lines[bodyStart:], "\n")
 	return header + "\n" + techRow + "\n\n" + body
 }
 
 func headingBlockEndIndex(lines []string, headIdx int) int {
 	for i := headIdx + 1; i < len(lines); i++ {
 		plain := strings.TrimSpace(ansiEscapeRE.ReplaceAllString(lines[i], ""))
 		if horizontalRuleLineRE.MatchString(plain) {
 			return i + 1
 		}
 		if plain == "" {
 			return i
 		}
 	}
 	return len(lines)
 }
 
 func outdentRenderedBody(rendered string) string {
 	lines := strings.Split(rendered, "\n")
 	if len(lines) < 2 {
 		return rendered
 	}
 
 	headIdx := -1
 	for i, line := range lines {
 		if strings.TrimSpace(line) != "" {
 			headIdx = i
 			break
 		}
 	}
 	if headIdx == -1 || headIdx == len(lines)-1 {
 		return rendered
 	}
 
 	bodyStart := headIdx + 1
 	for bodyStart < len(lines) && strings.TrimSpace(lines[bodyStart]) == "" {
 		bodyStart++
 	}
 	if bodyStart >= len(lines) {
 		return rendered
 	}
 
 	outdent := 0
 	for _, line := range lines[bodyStart:] {
 		if strings.TrimSpace(line) == "" || !strings.HasPrefix(line, " ") {
 			continue
 		}
 		indent := 0
 		for indent < len(line) && line[indent] == ' ' {
 			indent++
 		}
 		if outdent == 0 || indent < outdent {
 			outdent = indent
 		}
 	}
 	if outdent == 0 {
 		return rendered
 	}
 
 	for i := bodyStart; i < len(lines); i++ {
 		indent := 0
 		for indent < len(lines[i]) && indent < outdent && lines[i][indent] == ' ' {
 			indent++
 		}
 		lines[i] = lines[i][indent:]
 	}
 
 	return strings.Join(lines, "\n")
 }