krz/skunky-art

Alternative privacy frontend for DeviantArt.

clone: git clone https://gitbay.org/krz/skunky-art.git

v1.4.0: app/parsers.go · raw

  1package app
  2
  3import (
  4	"encoding/json"
  5	"strconv"
  6	"strings"
  7
  8	"github.com/krazywarez/devianter"
  9	"golang.org/x/net/html"
 10)
 11
 12// ParseComments renders a comment thread, nesting replies under the comment they
 13// answer. It returns a placeholder message rather than failing if the upstream
 14// fetch errored.
 15func (s skunkyart) ParseComments(c devianter.Comments, daError devianter.Error) string {
 16	if daError.RAW != nil {
 17		return "Failed to fetch comments :("
 18	}
 19
 20	var cmmts strings.Builder
 21	replied := make(map[int]string)
 22
 23	cmmts.WriteString("<details><summary>Comments: <b>")
 24	cmmts.WriteString(strconv.Itoa(c.Total))
 25	cmmts.WriteString("</b></summary>")
 26	for _, x := range c.Thread {
 27		replied[x.ID] = x.User.Username
 28		cmmts.WriteString(`<div class="msg`)
 29		if x.Parent > 0 {
 30			cmmts.WriteString(` reply`)
 31		}
 32		cmmts.WriteString(`"><p id="`)
 33		cmmts.WriteString(strconv.Itoa(x.ID))
 34		cmmts.WriteString(`"><img src="`)
 35		cmmts.WriteString(URLBuilder(s.Host, "media", "emojitar", x.User.Username, "?type=a"))
 36		cmmts.WriteString(`" width="30px" height="30px"><a href="`)
 37		cmmts.WriteString(URLBuilder(s.Host, "group_user", "?q=", x.User.Username, "&type=a"))
 38		cmmts.WriteString(`"><b`)
 39		cmmts.WriteString(` class="`)
 40		if x.User.Banned {
 41			cmmts.WriteString(`banned`)
 42		}
 43		if x.Author {
 44			cmmts.WriteString(`author`)
 45		}
 46		cmmts.WriteString(`">`)
 47		cmmts.WriteString(x.User.Username)
 48		cmmts.WriteString("</b></a> ")
 49
 50		if x.Parent > 0 {
 51			cmmts.WriteString(` In reply to <a href="`)
 52			cmmts.WriteString(s._pth)
 53			cmmts.WriteString("#")
 54			cmmts.WriteString(strconv.Itoa(x.Parent))
 55			cmmts.WriteString(`">`)
 56			if replied[x.Parent] == "" {
 57				cmmts.WriteString("???")
 58			} else {
 59				cmmts.WriteString(replied[x.Parent])
 60			}
 61			cmmts.WriteString("</a>")
 62		}
 63		cmmts.WriteString(" [")
 64		cmmts.WriteString(x.Posted.UTC().String())
 65		cmmts.WriteString("]<p>")
 66
 67		cmmts.WriteString(ParseDescription(s.Host, x.TextContent))
 68		cmmts.WriteString("<p>👍: ")
 69		cmmts.WriteString(strconv.Itoa(x.Likes))
 70		cmmts.WriteString(" ⏩: ")
 71		cmmts.WriteString(strconv.Itoa(x.Replies))
 72		cmmts.WriteString("</p></div>\n")
 73	}
 74	cmmts.WriteString(s.NavBase(DeviationList{
 75		Pages: 0,
 76		More:  c.HasMore,
 77	}))
 78	cmmts.WriteString("</details>")
 79	return cmmts.String()
 80}
 81
 82// DeviationList renders devs as an HTML grid, or as an Atom feed when the
 83// request asked for one and allowAtom permits it. NSFW entries are dropped
 84// unless the instance allows them. Passing content adds a navigation bar.
 85// VisibleDeviation reports whether a deviation may be shown by this instance.
 86//
 87// Both the HTML listing and the JSON API ask this, deliberately: an API that
 88// returned what the pages hide would leak exactly what hide-ai and the NSFW
 89// setting exist to withhold, and a second copy of the rule is a second thing to
 90// forget to update.
 91func VisibleDeviation(d *devianter.Deviation) bool {
 92	if d.AI && CFG.HideAI {
 93		return false
 94	}
 95	return !d.NSFW || CFG.Nsfw
 96}
 97
 98func (s skunkyart) DeviationList(devs []devianter.Deviation, allowAtom bool, content ...DeviationList) string {
 99	if s.Atom && s.Page > 1 {
100		s.ReturnHTTPError(400)
101		return ""
102	}
103
104	var list, listContent strings.Builder
105
106	for i, l := 0, len(devs); i < l; i++ {
107		data := &devs[i]
108		if !VisibleDeviation(data) {
109			continue
110		}
111		if preview, fullview := ParseMedia(s.Host, data.Media, 320), ParseMedia(s.Host, data.Media); true {
112			if allowAtom && s.Atom {
113				s.Writer.Header().Add("Content-Type", "application/atom+xml")
114				id := strconv.Itoa(data.ID)
115				listContent.WriteString(`<entry><author><name>`)
116				listContent.WriteString(data.Author.Username)
117				listContent.WriteString(`</name></author><title>`)
118				listContent.WriteString(data.Title)
119				listContent.WriteString(`</title><link rel="alternate" type="text/html" href="`)
120				listContent.WriteString(URLBuilder(s.Host, "post", data.Author.Username, "atom-"+id))
121				listContent.WriteString(`"/><id>`)
122				listContent.WriteString(id)
123				listContent.WriteString(`</id><published>`)
124				listContent.WriteString(data.PublishedTime.UTC().Format("Mon, 02 Jan 2006 15:04:05 -0700"))
125				listContent.WriteString(`</published>`)
126				listContent.WriteString(`<media:group><media:title>`)
127				listContent.WriteString(data.Title)
128				listContent.WriteString(`</media:title><media:thumbinal url="`)
129				listContent.WriteString(preview)
130				listContent.WriteString(`"/></media:group><content type="xhtml"><div xmlns="http://www.w3.org/1999/xhtml"><a href="`)
131				listContent.WriteString(ConvertDeviantArtURLToSkunkyArt(s.Host, data.Url))
132				listContent.WriteString(`"><img src="`)
133				listContent.WriteString(fullview)
134				listContent.WriteString(`"/></a><p>`)
135				listContent.WriteString(ParseDescription(s.Host, data.TextContent))
136				listContent.WriteString(`</p></div></content></entry>`)
137			} else {
138				listContent.WriteString(`<div class="block">`)
139				if fullview != "" && preview != "" {
140					listContent.WriteString(`<a title="open/download" href="`)
141					listContent.WriteString(fullview)
142					listContent.WriteString(`"><img loading="lazy" src="`)
143					listContent.WriteString(preview)
144					listContent.WriteString(`" width="15%"></a>`)
145				} else {
146					listContent.WriteString(`<h1>[ TEXT ]</h1>`)
147				}
148				listContent.WriteString(`<br><a href="`)
149				listContent.WriteString(ConvertDeviantArtURLToSkunkyArt(s.Host, data.Url))
150				listContent.WriteString(`">`)
151				listContent.WriteString(data.Author.Username)
152				listContent.WriteString(" - ")
153				listContent.WriteString(data.Title)
154
155				if data.NSFW {
156					listContent.WriteString(` [<span class="nsfw">NSFW</span>]`)
157				}
158				if data.AI {
159					listContent.WriteString(" [🤖]")
160				}
161				if data.DD {
162					listContent.WriteString(` [<span class="dd">DD</span>]`)
163				}
164
165				listContent.WriteString("</a></div>")
166			}
167		}
168	}
169
170	if allowAtom && s.Atom {
171		list.WriteString(`<?xml version="1.0" encoding="UTF-8"?><feed xmlns:media="http://search.yahoo.com/mrss/" xmlns="http://www.w3.org/2005/Atom">`)
172
173		list.WriteString(`<title>`)
174		switch {
175		case s.Type == 0:
176			list.WriteString("Daily Deviations")
177		case s.Type == 'g' && len(devs) != 0:
178			list.WriteString(devs[0].Author.Username)
179		default:
180			list.WriteString("SkunkyArt")
181		}
182		list.WriteString(`</title>`)
183
184		list.WriteString(`<link rel="alternate" href="`)
185		list.WriteString(s.Host)
186		list.WriteString(`"/>`)
187
188		list.WriteString(listContent.String())
189
190		list.WriteString("</feed>")
191		wr(s.Writer, list.String())
192	} else {
193		list.WriteString(`<div class="content">`)
194
195		list.WriteString(listContent.String())
196
197		list.WriteString("</div>")
198		if content != nil {
199			list.WriteString(s.NavBase(content[0]))
200		}
201	}
202
203	return list.String()
204}
205
206/* DESCRIPTION/COMMENT PARSER */
207
208// text is one styled run within a description: the rendered HTML, the raw source
209// it came from, and the offsets it spans in the original block.
210type text struct {
211	Txt    string
212	TxtRaw string
213	From   int
214	To     int
215}
216
217// ParseDescription renders a DeviantArt description into HTML, handling both the
218// Draft.js-style JSON payload and the plain HTML markup DeviantArt returns, and
219// rewriting embedded links and artwork references to point at this instance.
220// host is the request's scheme and host, as taken by URLBuilder.
221//
222// TODO: rewrite this whole mess.
223func ParseDescription(host string, dscr devianter.Text) string {
224	var parsedDescription strings.Builder
225	TagBuilder := func(content string, tags ...string) string {
226		l := len(tags)
227		for x := range l {
228			var htm strings.Builder
229			htm.WriteString("<")
230			htm.WriteString(tags[x])
231			htm.WriteString(">")
232
233			htm.WriteString(content)
234
235			htm.WriteString("</")
236			htm.WriteString(tags[x])
237			htm.WriteString(">")
238			content = htm.String()
239		}
240		return content
241	}
242	DeleteTrackingFromURL := func(url string) string {
243		if len(url) > 42 && url[:42] == "https://www.deviantart.com/users/outgoing?" {
244			url = url[42:]
245		}
246		return url
247	}
248
249	if description, dl := dscr.Html.Markup, len(dscr.Html.Markup); dl != 0 &&
250		description[0] == '{' &&
251		description[dl-1] == '}' {
252		var descr struct {
253			Blocks []struct {
254				Text              string `json:"text"`
255				Type              string `json:"type"`
256				InlineStyleRanges []struct {
257					Offset int    `json:"offset"`
258					Length int    `json:"length"`
259					Style  string `json:"style"`
260				} `json:"inlineStyleRanges"`
261				EntityRanges []struct {
262					Offset int `json:"offset"`
263					Length int `json:"length"`
264					Key    int `json:"key"`
265				} `json:"entityRanges"`
266				Data struct {
267					TextAlignment string `json:"textAlignment"`
268				} `json:"data"`
269			} `json:"blocks"`
270			EntityMap map[string]struct {
271				Type string `json:"type"`
272				Data struct {
273					URL    string `json:"url"`
274					Config struct {
275						// "aligment" is DeviantArt's own spelling; do not correct it.
276						Aligment string `json:"aligment"`
277						Width    int    `json:"width"`
278					} `json:"config"`
279					Data devianter.Deviation `json:"data"`
280				} `json:"data"`
281			} `json:"entityMap"`
282		}
283		e := json.Unmarshal([]byte(description), &descr)
284		try(e)
285
286		entities := make(map[int]devianter.Deviation)
287		urls := make(map[int]string)
288		for n, x := range descr.EntityMap {
289			num, _ := strconv.Atoi(n)
290			if x.Data.URL != "" {
291				urls[num] = DeleteTrackingFromURL(x.Data.URL)
292			}
293			entities[num] = x.Data.Data
294		}
295
296		for _, x := range descr.Blocks {
297			Styles := make([]text, len(x.InlineStyleRanges))
298
299			if len(x.InlineStyleRanges) != 0 {
300				var tags = make(map[int][]string)
301				for n, rngs := range x.InlineStyleRanges {
302					Styles := &Styles[n]
303					switch rngs.Style {
304					case "BOLD":
305						rngs.Style = "b"
306					case "UNDERLINE":
307						rngs.Style = "u"
308					case "ITALIC":
309						rngs.Style = "i"
310					}
311					Styles.From = rngs.Offset
312					Styles.To = rngs.Offset + rngs.Length
313					FT := Styles.From * Styles.To
314					tags[FT] = append(tags[FT], rngs.Style)
315				}
316				for n := range Styles {
317					Styles := &Styles[n]
318					Styles.TxtRaw = x.Text[Styles.From:Styles.To]
319					Styles.Txt = TagBuilder(Styles.TxtRaw, tags[Styles.From*Styles.To]...)
320				}
321			}
322
323			switch x.Type {
324			case "atomic":
325				if len(x.EntityRanges) != 0 {
326					d := entities[x.EntityRanges[0].Key]
327					parsedDescription.WriteString(`<a href="`)
328					parsedDescription.WriteString(ConvertDeviantArtURLToSkunkyArt(host, d.Url))
329					parsedDescription.WriteString(`"><img width="50%" src="`)
330					parsedDescription.WriteString(ParseMedia(host, d.Media))
331					parsedDescription.WriteString(`" title="`)
332					parsedDescription.WriteString(d.Author.Username)
333					parsedDescription.WriteString(" - ")
334					parsedDescription.WriteString(d.Title)
335					parsedDescription.WriteString(`"></a>`)
336				}
337			case "unstyled":
338				if l := len(Styles); l != 0 {
339					for n, r := range Styles {
340						var tag string
341						if x.Type == "header-two" {
342							tag = "h2"
343						}
344
345						parsedDescription.WriteString(x.Text[:r.From])
346						if len(urls) != 0 && len(x.EntityRanges) != 0 {
347							ra := &x.EntityRanges[0]
348
349							parsedDescription.WriteString(`<a target="_blank" href="`)
350							parsedDescription.WriteString(urls[ra.Key])
351							parsedDescription.WriteString(`">`)
352							parsedDescription.WriteString(r.Txt)
353							parsedDescription.WriteString(`</a>`)
354						} else if l > n+1 {
355							parsedDescription.WriteString(r.Txt)
356						}
357						parsedDescription.WriteString(TagBuilder(tag, x.Text[r.To:]))
358					}
359				} else {
360					parsedDescription.WriteString(x.Text)
361				}
362			}
363			parsedDescription.WriteString("<br>")
364		}
365	} else if dl != 0 {
366		for tt := html.NewTokenizer(strings.NewReader(dscr.Html.Markup)); ; {
367			switch tt.Next() {
368			case html.ErrorToken:
369				return parsedDescription.String()
370			case html.CommentToken, html.DoctypeToken:
371				// No renderable content; skip.
372			case html.StartTagToken, html.EndTagToken, html.SelfClosingTagToken:
373				token := tt.Token()
374				switch token.Data {
375				case "a":
376					for _, a := range token.Attr {
377						if a.Key == "href" {
378							url := DeleteTrackingFromURL(a.Val)
379							parsedDescription.WriteString(`<a target="_blank" href="`)
380							parsedDescription.WriteString(url)
381							parsedDescription.WriteString(`">`)
382							parsedDescription.WriteString(GetValueOfTag(tt))
383							parsedDescription.WriteString("</a> ")
384						}
385					}
386				case "img":
387					var uri, title string
388					for b, a := range token.Attr {
389						switch a.Key {
390						case "src":
391							if len(a.Val) > 9 && a.Val[8:9] == "e" {
392								uri = URLBuilder(host, "media", "emojitar", a.Val[37:len(a.Val)-4], "?type=e")
393							}
394						case "title":
395							title = a.Val
396						}
397						if title != "" {
398							for x := -1; x < b; x++ {
399								parsedDescription.WriteString(`<img src="`)
400								parsedDescription.WriteString(uri)
401								parsedDescription.WriteString(`" title="`)
402								parsedDescription.WriteString(title)
403								parsedDescription.WriteString(`">`)
404							}
405						}
406					}
407				case "br", "li", "ul", "p", "b":
408					parsedDescription.WriteString(token.String())
409				case "div":
410					parsedDescription.WriteString("<p> ")
411				}
412			case html.TextToken:
413				parsedDescription.Write(tt.Text())
414			}
415		}
416	}
417
418	return parsedDescription.String()
419}