dzming.li
A vibe coded tangled fork which supports pijul.
1// Package markup is an umbrella package for all markups and their renderers.
2package markup
3
4import (
5 "bytes"
6 "fmt"
7 "io"
8 "io/fs"
9 "net/url"
10 "path"
11 "strings"
12
13 chromahtml "github.com/alecthomas/chroma/v2/formatters/html"
14 "github.com/alecthomas/chroma/v2/styles"
15 "github.com/yuin/goldmark"
16 "github.com/yuin/goldmark-emoji"
17 highlighting "github.com/yuin/goldmark-highlighting/v2"
18 "github.com/yuin/goldmark/ast"
19 "github.com/yuin/goldmark/extension"
20 "github.com/yuin/goldmark/parser"
21 "github.com/yuin/goldmark/renderer/html"
22 "github.com/yuin/goldmark/text"
23 "github.com/yuin/goldmark/util"
24 callout "gitlab.com/staticnoise/goldmark-callout"
25 htmlparse "golang.org/x/net/html"
26
27 "tangled.org/core/api/tangled"
28 textension "tangled.org/core/appview/pages/markup/extension"
29 "tangled.org/core/appview/pages/repoinfo"
30)
31
32// RendererType defines the type of renderer to use based on context
33type RendererType int
34
35const (
36 // RendererTypeRepoMarkdown is for repository documentation markdown files
37 RendererTypeRepoMarkdown RendererType = iota
38 // RendererTypeDefault is non-repo markdown, like issues/pulls/comments.
39 RendererTypeDefault
40)
41
42// RenderContext holds the contextual data for rendering markdown.
43// It can be initialized empty, and that'll skip any transformations.
44type RenderContext struct {
45 CamoUrl string
46 CamoSecret string
47 repoinfo.RepoInfo
48 IsDev bool
49 RendererType RendererType
50 Files fs.FS
51}
52
53func NewMarkdown() goldmark.Markdown {
54 md := goldmark.New(
55 goldmark.WithExtensions(
56 extension.GFM,
57 highlighting.NewHighlighting(
58 highlighting.WithFormatOptions(
59 chromahtml.Standalone(false),
60 chromahtml.WithClasses(true),
61 ),
62 highlighting.WithCustomStyle(styles.Get("catppuccin-latte")),
63 ),
64 extension.NewFootnote(
65 extension.WithFootnoteIDPrefix([]byte("footnote")),
66 ),
67 callout.CalloutExtention,
68 textension.AtExt,
69 emoji.Emoji,
70 ),
71 goldmark.WithParserOptions(
72 parser.WithAutoHeadingID(),
73 ),
74 goldmark.WithRendererOptions(html.WithUnsafe()),
75 )
76 return md
77}
78
79func (rctx *RenderContext) RenderMarkdown(source string) string {
80 return rctx.RenderMarkdownWith(source, NewMarkdown())
81}
82
83func (rctx *RenderContext) RenderMarkdownWith(source string, md goldmark.Markdown) string {
84 if rctx != nil {
85 var transformers []util.PrioritizedValue
86
87 transformers = append(transformers, util.Prioritized(&MarkdownTransformer{rctx: rctx}, 10000))
88
89 md.Parser().AddOptions(
90 parser.WithASTTransformers(transformers...),
91 )
92 }
93
94 var buf bytes.Buffer
95 if err := md.Convert([]byte(source), &buf); err != nil {
96 return source
97 }
98
99 var processed strings.Builder
100 if err := postProcess(rctx, strings.NewReader(buf.String()), &processed); err != nil {
101 return source
102 }
103
104 return processed.String()
105}
106
107func postProcess(ctx *RenderContext, input io.Reader, output io.Writer) error {
108 node, err := htmlparse.Parse(io.MultiReader(
109 strings.NewReader("<html><body>"),
110 input,
111 strings.NewReader("</body></html>"),
112 ))
113 if err != nil {
114 return fmt.Errorf("failed to parse html: %w", err)
115 }
116
117 if node.Type == htmlparse.DocumentNode {
118 node = node.FirstChild
119 }
120
121 visitNode(ctx, node)
122
123 newNodes := make([]*htmlparse.Node, 0, 5)
124
125 if node.Data == "html" {
126 node = node.FirstChild
127 for node != nil && node.Data != "body" {
128 node = node.NextSibling
129 }
130 }
131 if node != nil {
132 if node.Data == "body" {
133 child := node.FirstChild
134 for child != nil {
135 newNodes = append(newNodes, child)
136 child = child.NextSibling
137 }
138 } else {
139 newNodes = append(newNodes, node)
140 }
141 }
142
143 for _, node := range newNodes {
144 if err := htmlparse.Render(output, node); err != nil {
145 return fmt.Errorf("failed to render processed html: %w", err)
146 }
147 }
148
149 return nil
150}
151
152func visitNode(ctx *RenderContext, node *htmlparse.Node) {
153 switch node.Type {
154 case htmlparse.ElementNode:
155 switch node.Data {
156 case "img", "source":
157 for i, attr := range node.Attr {
158 if attr.Key != "src" {
159 continue
160 }
161
162 camoUrl, _ := url.Parse(ctx.CamoUrl)
163 dstUrl, _ := url.Parse(attr.Val)
164 if dstUrl.Host != camoUrl.Host {
165 attr.Val = ctx.imageFromKnotTransformer(attr.Val)
166 attr.Val = ctx.camoImageLinkTransformer(attr.Val)
167 node.Attr[i] = attr
168 }
169 }
170 }
171
172 for n := node.FirstChild; n != nil; n = n.NextSibling {
173 visitNode(ctx, n)
174 }
175 default:
176 }
177}
178
179type MarkdownTransformer struct {
180 rctx *RenderContext
181}
182
183func (a *MarkdownTransformer) Transform(node *ast.Document, reader text.Reader, pc parser.Context) {
184 _ = ast.Walk(node, func(n ast.Node, entering bool) (ast.WalkStatus, error) {
185 if !entering {
186 return ast.WalkContinue, nil
187 }
188
189 switch a.rctx.RendererType {
190 case RendererTypeRepoMarkdown:
191 switch n := n.(type) {
192 case *ast.Heading:
193 a.rctx.anchorHeadingTransformer(n)
194 case *ast.Link:
195 a.rctx.relativeLinkTransformer(n)
196 case *ast.Image:
197 a.rctx.imageFromKnotAstTransformer(n)
198 a.rctx.camoImageLinkAstTransformer(n)
199 }
200 case RendererTypeDefault:
201 switch n := n.(type) {
202 case *ast.Heading:
203 a.rctx.anchorHeadingTransformer(n)
204 case *ast.Image:
205 a.rctx.imageFromKnotAstTransformer(n)
206 a.rctx.camoImageLinkAstTransformer(n)
207 }
208 }
209
210 return ast.WalkContinue, nil
211 })
212}
213
214func (rctx *RenderContext) relativeLinkTransformer(link *ast.Link) {
215
216 dst := string(link.Destination)
217
218 if isAbsoluteUrl(dst) || isFragment(dst) || isMail(dst) {
219 return
220 }
221
222 actualPath := rctx.actualPath(dst)
223
224 newPath := path.Join("/", rctx.RepoInfo.FullName(), "tree", rctx.RepoInfo.Ref, actualPath)
225 link.Destination = []byte(newPath)
226}
227
228func (rctx *RenderContext) imageFromKnotTransformer(dst string) string {
229 if isAbsoluteUrl(dst) {
230 return dst
231 }
232
233 scheme := "https"
234 if rctx.IsDev {
235 scheme = "http"
236 }
237
238 actualPath := rctx.actualPath(dst)
239
240 repoName := fmt.Sprintf("%s/%s", rctx.RepoInfo.OwnerDid, rctx.RepoInfo.Name)
241
242 query := fmt.Sprintf("repo=%s&ref=%s&path=%s&raw=true",
243 url.QueryEscape(repoName), url.QueryEscape(rctx.RepoInfo.Ref), actualPath)
244
245 parsedURL := &url.URL{
246 Scheme: scheme,
247 Host: rctx.Knot,
248 Path: path.Join("/xrpc", tangled.RepoBlobNSID),
249 RawQuery: query,
250 }
251 newPath := parsedURL.String()
252 return newPath
253}
254
255func (rctx *RenderContext) imageFromKnotAstTransformer(img *ast.Image) {
256 dst := string(img.Destination)
257 img.Destination = []byte(rctx.imageFromKnotTransformer(dst))
258}
259
260func (rctx *RenderContext) anchorHeadingTransformer(h *ast.Heading) {
261 idGeneric, exists := h.AttributeString("id")
262 if !exists {
263 return // no id, nothing to do
264 }
265 id, ok := idGeneric.([]byte)
266 if !ok {
267 return
268 }
269
270 // create anchor link
271 anchor := ast.NewLink()
272 anchor.Destination = fmt.Appendf(nil, "#%s", string(id))
273 anchor.SetAttribute([]byte("class"), []byte("anchor"))
274
275 // create icon text
276 iconText := ast.NewString([]byte("#"))
277 anchor.AppendChild(anchor, iconText)
278
279 // set class on heading
280 h.SetAttribute([]byte("class"), []byte("heading"))
281
282 // append anchor to heading
283 h.AppendChild(h, anchor)
284}
285
286// actualPath decides when to join the file path with the
287// current repository directory (essentially only when the link
288// destination is relative. if it's absolute then we assume the
289// user knows what they're doing.)
290func (rctx *RenderContext) actualPath(dst string) string {
291 if path.IsAbs(dst) {
292 return dst
293 }
294
295 return path.Join(rctx.CurrentDir, dst)
296}
297
298func isAbsoluteUrl(link string) bool {
299 parsed, err := url.Parse(link)
300 if err != nil {
301 return false
302 }
303 return parsed.IsAbs()
304}
305
306func isFragment(link string) bool {
307 return strings.HasPrefix(link, "#")
308}
309
310func isMail(link string) bool {
311 return strings.HasPrefix(link, "mailto:")
312}