diff options
Diffstat (limited to 'internal/router/template.go')
| -rw-r--r-- | internal/router/template.go | 158 |
1 files changed, 126 insertions, 32 deletions
diff --git a/internal/router/template.go b/internal/router/template.go index 0bae96548..1e3b2e715 100644 --- a/internal/router/template.go +++ b/internal/router/template.go @@ -25,7 +25,9 @@ import ( "path/filepath" "reflect" "regexp" + "slices" "strings" + "sync" "unsafe" apimodel "code.superseriousbusiness.org/gotosocial/internal/api/model" @@ -134,25 +136,25 @@ func LoadTemplates(engine *gin.Engine) error { } var funcMap = template.FuncMap{ - "add": add, - "acctInstance": acctInstance, - "objectPosition": objectPosition, - "demojify": demojify, - "deref": deref, - "emojify": emojify, - "escape": escape, - "increment": increment, - "indent": indent, - "indentAttr": indentAttr, - "isNil": isNil, - "outdentPre": outdentPre, - "noescapeAttr": noescapeAttr, - "noescape": noescape, - "oddOrEven": oddOrEven, - "subtract": subtract, - "timestampPrecise": timestampPrecise, - "timestampVague": timestampVague, - "visibilityIcon": visibilityIcon, + "add": add, + "acctInstance": acctInstance, + "objectPosition": objectPosition, + "demojify": demojify, + "deref": deref, + "emojify": emojify, + "escape": escape, + "increment": increment, + "indent": indent, + "indentAttr": indentAttr, + "isNil": isNil, + "outdentPreformatted": outdentPreformatted, + "noescapeAttr": noescapeAttr, + "noescape": noescape, + "oddOrEven": oddOrEven, + "subtract": subtract, + "timestampPrecise": timestampPrecise, + "timestampVague": timestampVague, + "visibilityIcon": visibilityIcon, } func oddOrEven(n int) string { @@ -291,11 +293,31 @@ func subtract(n1 int, n2 int) int { } var ( - indentRegex = regexp.MustCompile(`(?m)^`) + // Find starts of lines to replace with indent. + indentRegex = regexp.MustCompile(`(?m)^`) + + // One indent level. indentStr = " " indentStrLen = len(indentStr) - indents = strings.Repeat(indentStr, 12) - indentPre = regexp.MustCompile(fmt.Sprintf(`(?Ums)^((?:%s)+)<pre>.*</pre>`, indentStr)) + + // Preformatted slice of indents. + indents = strings.Repeat(indentStr, 12) + + // Measure indent at the start of a line. + indentDepthStr = fmt.Sprintf(`^((?:%s)+)`, indentStr) + indentDepth = regexp.MustCompile(`(?m)` + indentDepthStr) + + // Find <pre> tags and determine how indented they are. + indentPre = regexp.MustCompile(fmt.Sprintf(`(?Ums)%s<pre>.*</pre>`, indentDepthStr)) + // Find content of alt or title attributes. + indentAltOrTitle = regexp.MustCompile(`(?Ums)\b(?:alt|title)="(.*)"(?:\b|>|$)`) + + // Map of lazily-compiled replaceIndent + // regexes, keyed by the indent they + // replace, to avoid recompilation. + // + // At *most* 12 entries long. + replaceIndents = sync.Map{} ) // indent appropriately indents the given html @@ -318,32 +340,104 @@ func indentAttr(n int, html template.HTMLAttr) template.HTMLAttr { return noescapeAttr(out) } -// outdentPre outdents all `<pre></pre>` tags in the -// given HTML so that they render correctly in code -// blocks, even if they were indented before. -func outdentPre(html template.HTML) template.HTML { +// outdentPreformatted outdents all preformatted text in +// the given HTML, ie., in `alt` and `title` attributes, +// and between `<pre>` tags, so that it renders correctly, +// even if it was indented before. +func outdentPreformatted(html template.HTML) template.HTML { input := string(html) output := regexes.ReplaceAllStringFunc(indentPre, input, func(match string, buf *bytes.Buffer) string { // Reuse the regex to pull out submatches. matches := indentPre.FindAllStringSubmatch(match, -1) + + // Ensure matches + // expected length. if len(matches) != 1 { return match } + // Ensure inner matches + // expected length. + innerMatches := matches[0] + if len(innerMatches) != 2 { + return match + } + var ( - indented = matches[0][0] - indent = matches[0][1] + indentedContent = innerMatches[0] + indent = innerMatches[1] ) - // Outdent everything in the inner match, add - // a newline at the end to make it a bit neater. - outdented := strings.ReplaceAll(indented, indent, "") + // Outdent everything in the inner match. + outdented := strings.ReplaceAll(indentedContent, indent, "") // Replace original match with the outdented version. - return strings.ReplaceAll(match, indented, outdented) + return strings.ReplaceAll(match, indentedContent, outdented) }, ) + + output = regexes.ReplaceAllStringFunc(indentAltOrTitle, output, + func(match string, buf *bytes.Buffer) string { + // Reuse the regex to pull out submatches. + matches := indentAltOrTitle.FindAllStringSubmatch(match, -1) + + // Ensure matches + // expected length. + if len(matches) != 1 { + return match + } + + // Ensure inner matches + // expected length. + innerMatches := matches[0] + if len(innerMatches) != 2 { + return match + } + + // The content of the alt or title + // attr inside quotation marks. + indentedContent := innerMatches[1] + + // Find all indents in this text. + indents := indentDepth.FindAllString(indentedContent, -1) + if len(indents) == 0 { + // No indents in this text, + // it's probably just something + // inline like `alt="whatever"`. + return match + } + + // Find the shortest indent as this + // is undoubtedly the one we added. + // + // By targeting the shortest one we + // avoid removing user-inserted + // whitespace at the start of lines + // of alt text (eg., in poetry etc). + slices.Sort(indents) + indent := indents[0] + + // Load or create + store the + // regex to replace this indent, + // avoiding recompilation. + var replaceIndent *regexp.Regexp + if replaceIndentI, ok := replaceIndents.Load(indent); ok { + // Got regex for this indent. + replaceIndent = replaceIndentI.(*regexp.Regexp) + } else { + // No regex stored for + // this indent yet, store it. + replaceIndent = regexp.MustCompile(`(?m)^` + indent) + replaceIndents.Store(indent, replaceIndent) + } + + // Remove all occurrences of the indent + // at the start of a line in the match. + return replaceIndent.ReplaceAllString(match, "") + }, + ) + return noescape(output) } |