feat: add url shortner

2026-05-11 16:13:22 +05:30
parent f2889a5679
commit 5e0a484239
17 changed files with 1305 additions and 13 deletions
@@ -0,0 +1,189 @@
+package shorturl
+
+import (
+	"net/url"
+	"strings"
+)
+
+// Parsed contains analytics-friendly components extracted from a long URL.
+// Unrecognized paths produce ContentType = "unknown" with the other fields
+// left empty.
+type Parsed struct {
+	Path           string
+	ContentType    string
+	BookCode       string
+	Division       string
+	Chapter        string
+	Verse          string
+	Slug           string
+	HasHighlight   bool
+	HighlightParam string
+}
+
+// ParsePath decomposes a long URL (path + query) into analytics columns.
+// It expects a same-site relative path; callers should run ValidatePath first.
+func ParsePath(longURL string) Parsed {
+	u, err := url.Parse("http://x" + longURL)
+	if err != nil {
+		return Parsed{Path: longURL, ContentType: "unknown"}
+	}
+
+	hl := u.Query().Get("hl")
+	out := Parsed{
+		Path:           u.Path,
+		HasHighlight:   hl != "",
+		HighlightParam: truncate(hl, 1024),
+		ContentType:    "unknown",
+	}
+
+	parts := splitPath(u.Path)
+	if len(parts) == 0 {
+		return out
+	}
+
+	switch parts[0] {
+	case "books":
+		out = parseBooks(parts, out)
+	case "letters":
+		if len(parts) >= 2 {
+			out.ContentType = "letter"
+			out.Slug = parts[1]
+		}
+	case "transcriptions":
+		if len(parts) >= 2 {
+			out.ContentType = "transcription"
+			out.Slug = parts[1]
+		}
+	case "essays":
+		if len(parts) >= 2 {
+			out.ContentType = "essay"
+			out.Slug = parts[1]
+		}
+	case "journals":
+		if len(parts) >= 2 {
+			out.ContentType = "journal"
+			out.Slug = parts[1]
+		}
+		if len(parts) >= 3 {
+			out.Chapter = parts[2]
+		}
+	case "magazines":
+		if len(parts) >= 2 {
+			out.ContentType = "magazine"
+			out.Slug = parts[1]
+		}
+		if len(parts) >= 3 {
+			out.Chapter = parts[2]
+		}
+	case "other-documents":
+		if len(parts) >= 2 {
+			out.ContentType = "other_document"
+			out.Slug = parts[1]
+		}
+		if len(parts) >= 3 {
+			out.Chapter = parts[2]
+		}
+	case "glossary":
+		out.ContentType = "glossary"
+		if len(parts) >= 2 {
+			out.Slug = parts[1]
+		}
+	}
+	return out
+}
+
+// verseBookCodes are the books whose URL pattern has a per-verse leaf.
+var verseBookCodes = map[string]bool{
+	"bg":     true,
+	"sb1962": true,
+	"iso":    true,
+	"noi":    true,
+	"bs":     true,
+	"mm":     true,
+	"nbs":    true,
+}
+
+// divisionVerseBookCodes have an extra division segment (canto for SB, līlā for CC).
+var divisionVerseBookCodes = map[string]bool{
+	"sb": true,
+	"cc": true,
+}
+
+func parseBooks(parts []string, out Parsed) Parsed {
+	if len(parts) < 2 {
+		out.ContentType = "book"
+		return out
+	}
+	code := parts[1]
+	out.BookCode = code
+
+	if divisionVerseBookCodes[code] {
+		// /books/sb/{canto}/{chapter}/{verse}
+		// /books/cc/{lila}/{chapter}/{verse}
+		if len(parts) >= 5 {
+			out.ContentType = "verse"
+			out.Division = parts[2]
+			out.Chapter = parts[3]
+			out.Verse = parts[4]
+		} else if len(parts) >= 4 {
+			out.ContentType = "verse_index"
+			out.Division = parts[2]
+			out.Chapter = parts[3]
+		} else {
+			out.ContentType = "book"
+		}
+		return out
+	}
+
+	if verseBookCodes[code] {
+		// /books/{code}/{chapter}/{verse}  (BG, SB1962, BS, MM, NBS)
+		// /books/{code}/{slug}             (ISO, NOI — single-segment leaf)
+		if len(parts) >= 4 {
+			out.ContentType = "verse"
+			out.Chapter = parts[2]
+			out.Verse = parts[3]
+		} else if len(parts) >= 3 {
+			out.ContentType = "verse"
+			out.Slug = parts[2]
+		} else {
+			out.ContentType = "book"
+		}
+		return out
+	}
+
+	// All other book codes are prose. KB has /kb/{volume}/{slug}; others /code/{slug}.
+	if code == "kb" && len(parts) >= 4 {
+		out.ContentType = "prose"
+		out.Division = parts[2] // volume number
+		out.Slug = parts[3]
+		return out
+	}
+	if len(parts) >= 3 {
+		out.ContentType = "prose"
+		out.Slug = parts[2]
+		return out
+	}
+	out.ContentType = "book"
+	return out
+}
+
+func splitPath(p string) []string {
+	p = strings.Trim(p, "/")
+	if p == "" {
+		return nil
+	}
+	parts := strings.Split(p, "/")
+	for i, s := range parts {
+		if decoded, err := url.PathUnescape(s); err == nil {
+			parts[i] = decoded
+		}
+	}
+	return parts
+}
+
+func truncate(s string, n int) string {
+	if len(s) <= n {
+		return s
+	}
+	return s[:n]
+}