1package md2man
2
3import (
4 "bytes"
5 "fmt"
6 "html"
7 "strings"
8
9 "github.com/russross/blackfriday"
10)
11
12type roffRenderer struct {
13 ListCounters []int
14}
15
16// RoffRenderer creates a new blackfriday Renderer for generating roff documents
17// from markdown
18func RoffRenderer(flags int) blackfriday.Renderer {
19 return &roffRenderer{}
20}
21
22func (r *roffRenderer) GetFlags() int {
23 return 0
24}
25
26func (r *roffRenderer) TitleBlock(out *bytes.Buffer, text []byte) {
27 out.WriteString(".TH ")
28
29 splitText := bytes.Split(text, []byte("\n"))
30 for i, line := range splitText {
31 line = bytes.TrimPrefix(line, []byte("% "))
32 if i == 0 {
33 line = bytes.Replace(line, []byte("("), []byte("\" \""), 1)
34 line = bytes.Replace(line, []byte(")"), []byte("\" \""), 1)
35 }
36 line = append([]byte("\""), line...)
37 line = append(line, []byte("\" ")...)
38 out.Write(line)
39 }
40 out.WriteString("\n")
41
42 // disable hyphenation
43 out.WriteString(".nh\n")
44 // disable justification (adjust text to left margin only)
45 out.WriteString(".ad l\n")
46}
47
48func (r *roffRenderer) BlockCode(out *bytes.Buffer, text []byte, lang string) {
49 out.WriteString("\n.PP\n.RS\n\n.nf\n")
50 escapeSpecialChars(out, text)
51 out.WriteString("\n.fi\n.RE\n")
52}
53
54func (r *roffRenderer) BlockQuote(out *bytes.Buffer, text []byte) {
55 out.WriteString("\n.PP\n.RS\n")
56 out.Write(text)
57 out.WriteString("\n.RE\n")
58}
59
60func (r *roffRenderer) BlockHtml(out *bytes.Buffer, text []byte) { // nolint: golint
61 out.Write(text)
62}
63
64func (r *roffRenderer) Header(out *bytes.Buffer, text func() bool, level int, id string) {
65 marker := out.Len()
66
67 switch {
68 case marker == 0:
69 // This is the doc header
70 out.WriteString(".TH ")
71 case level == 1:
72 out.WriteString("\n\n.SH ")
73 case level == 2:
74 out.WriteString("\n.SH ")
75 default:
76 out.WriteString("\n.SS ")
77 }
78
79 if !text() {
80 out.Truncate(marker)
81 return
82 }
83}
84
85func (r *roffRenderer) HRule(out *bytes.Buffer) {
86 out.WriteString("\n.ti 0\n\\l'\\n(.lu'\n")
87}
88
89func (r *roffRenderer) List(out *bytes.Buffer, text func() bool, flags int) {
90 marker := out.Len()
91 r.ListCounters = append(r.ListCounters, 1)
92 out.WriteString("\n.RS\n")
93 if !text() {
94 out.Truncate(marker)
95 return
96 }
97 r.ListCounters = r.ListCounters[:len(r.ListCounters)-1]
98 out.WriteString("\n.RE\n")
99}
100
101func (r *roffRenderer) ListItem(out *bytes.Buffer, text []byte, flags int) {
102 if flags&blackfriday.LIST_TYPE_ORDERED != 0 {
103 out.WriteString(fmt.Sprintf(".IP \"%3d.\" 5\n", r.ListCounters[len(r.ListCounters)-1]))
104 r.ListCounters[len(r.ListCounters)-1]++
105 } else {
106 out.WriteString(".IP \\(bu 2\n")
107 }
108 out.Write(text)
109 out.WriteString("\n")
110}
111
112func (r *roffRenderer) Paragraph(out *bytes.Buffer, text func() bool) {
113 marker := out.Len()
114 out.WriteString("\n.PP\n")
115 if !text() {
116 out.Truncate(marker)
117 return
118 }
119 if marker != 0 {
120 out.WriteString("\n")
121 }
122}
123
124func (r *roffRenderer) Table(out *bytes.Buffer, header []byte, body []byte, columnData []int) {
125 out.WriteString("\n.TS\nallbox;\n")
126
127 maxDelims := 0
128 lines := strings.Split(strings.TrimRight(string(header), "\n")+"\n"+strings.TrimRight(string(body), "\n"), "\n")
129 for _, w := range lines {
130 curDelims := strings.Count(w, "\t")
131 if curDelims > maxDelims {
132 maxDelims = curDelims
133 }
134 }
135 out.Write([]byte(strings.Repeat("l ", maxDelims+1) + "\n"))
136 out.Write([]byte(strings.Repeat("l ", maxDelims+1) + ".\n"))
137 out.Write(header)
138 if len(header) > 0 {
139 out.Write([]byte("\n"))
140 }
141
142 out.Write(body)
143 out.WriteString("\n.TE\n")
144}
145
146func (r *roffRenderer) TableRow(out *bytes.Buffer, text []byte) {
147 if out.Len() > 0 {
148 out.WriteString("\n")
149 }
150 out.Write(text)
151}
152
153func (r *roffRenderer) TableHeaderCell(out *bytes.Buffer, text []byte, align int) {
154 if out.Len() > 0 {
155 out.WriteString("\t")
156 }
157 if len(text) == 0 {
158 text = []byte{' '}
159 }
160 out.Write([]byte("\\fB\\fC" + string(text) + "\\fR"))
161}
162
163func (r *roffRenderer) TableCell(out *bytes.Buffer, text []byte, align int) {
164 if out.Len() > 0 {
165 out.WriteString("\t")
166 }
167 if len(text) > 30 {
168 text = append([]byte("T{\n"), text...)
169 text = append(text, []byte("\nT}")...)
170 }
171 if len(text) == 0 {
172 text = []byte{' '}
173 }
174 out.Write(text)
175}
176
177func (r *roffRenderer) Footnotes(out *bytes.Buffer, text func() bool) {
178
179}
180
181func (r *roffRenderer) FootnoteItem(out *bytes.Buffer, name, text []byte, flags int) {
182
183}
184
185func (r *roffRenderer) AutoLink(out *bytes.Buffer, link []byte, kind int) {
186 out.WriteString("\n\\[la]")
187 out.Write(link)
188 out.WriteString("\\[ra]")
189}
190
191func (r *roffRenderer) CodeSpan(out *bytes.Buffer, text []byte) {
192 out.WriteString("\\fB\\fC")
193 escapeSpecialChars(out, text)
194 out.WriteString("\\fR")
195}
196
197func (r *roffRenderer) DoubleEmphasis(out *bytes.Buffer, text []byte) {
198 out.WriteString("\\fB")
199 out.Write(text)
200 out.WriteString("\\fP")
201}
202
203func (r *roffRenderer) Emphasis(out *bytes.Buffer, text []byte) {
204 out.WriteString("\\fI")
205 out.Write(text)
206 out.WriteString("\\fP")
207}
208
209func (r *roffRenderer) Image(out *bytes.Buffer, link []byte, title []byte, alt []byte) {
210}
211
212func (r *roffRenderer) LineBreak(out *bytes.Buffer) {
213 out.WriteString("\n.br\n")
214}
215
216func (r *roffRenderer) Link(out *bytes.Buffer, link []byte, title []byte, content []byte) {
217 out.Write(content)
218 r.AutoLink(out, link, 0)
219}
220
221func (r *roffRenderer) RawHtmlTag(out *bytes.Buffer, tag []byte) { // nolint: golint
222 out.Write(tag)
223}
224
225func (r *roffRenderer) TripleEmphasis(out *bytes.Buffer, text []byte) {
226 out.WriteString("\\s+2")
227 out.Write(text)
228 out.WriteString("\\s-2")
229}
230
231func (r *roffRenderer) StrikeThrough(out *bytes.Buffer, text []byte) {
232}
233
234func (r *roffRenderer) FootnoteRef(out *bytes.Buffer, ref []byte, id int) {
235
236}
237
238func (r *roffRenderer) Entity(out *bytes.Buffer, entity []byte) {
239 out.WriteString(html.UnescapeString(string(entity)))
240}
241
242func (r *roffRenderer) NormalText(out *bytes.Buffer, text []byte) {
243 escapeSpecialChars(out, text)
244}
245
246func (r *roffRenderer) DocumentHeader(out *bytes.Buffer) {
247}
248
249func (r *roffRenderer) DocumentFooter(out *bytes.Buffer) {
250}
251
252func needsBackslash(c byte) bool {
253 for _, r := range []byte("-_&\\~") {
254 if c == r {
255 return true
256 }
257 }
258 return false
259}
260
261func escapeSpecialChars(out *bytes.Buffer, text []byte) {
262 for i := 0; i < len(text); i++ {
263 // escape initial apostrophe or period
264 if len(text) >= 1 && (text[0] == '\'' || text[0] == '.') {
265 out.WriteString("\\&")
266 }
267
268 // directly copy normal characters
269 org := i
270
271 for i < len(text) && !needsBackslash(text[i]) {
272 i++
273 }
274 if i > org {
275 out.Write(text[org:i])
276 }
277
278 // escape a character
279 if i >= len(text) {
280 break
281 }
282 out.WriteByte('\\')
283 out.WriteByte(text[i])
284 }
285}