0.10.6

2026-07-30 20:07:51 +07:00
commit 92660a4ba0
228 changed files with 24496 additions and 0 deletions
@@ -0,0 +1,107 @@
+import Foundation
+
+/// Builds and removes the plain-text quote used when a peer does not render
+/// XEP-0461 replies. XEP-0428 offsets are Unicode scalar offsets, not UTF-16.
+enum MessageReplyFallback {
+    struct Parsed: Equatable, Sendable {
+        let body: String
+        let preview: String?
+    }
+
+    static func make(author: String, preview: String) -> (prefix: String, scalarCount: Int) {
+        let safeAuthor = author
+            .replacingOccurrences(of: "\n", with: " ")
+            .trimmingCharacters(in: .whitespacesAndNewlines)
+        let quoteLines = preview
+            .trimmingCharacters(in: .whitespacesAndNewlines)
+            .split(separator: "\n", omittingEmptySubsequences: false)
+            .prefix(8)
+            .map { "> \($0)" }
+        let prefix = (["> \(safeAuthor) написал(а):"] + quoteLines).joined(separator: "\n") + "\n\n"
+        return (prefix, prefix.unicodeScalars.count)
+    }
+
+    static func parse(
+        body: String,
+        fallbackStart: Int?,
+        fallbackEnd: Int?
+    ) -> Parsed {
+        if let fallbackStart,
+           let fallbackEnd,
+           let fallback = scalarSubstring(body, start: fallbackStart, end: fallbackEnd),
+           let stripped = removingScalarRange(body, start: fallbackStart, end: fallbackEnd) {
+            return Parsed(
+                body: stripped.trimmingCharacters(in: .whitespacesAndNewlines),
+                preview: quotePreview(from: fallback)
+            )
+        }
+        return parseLegacyQuote(body) ?? Parsed(body: body, preview: nil)
+    }
+
+    static func parseLegacyQuote(_ body: String) -> Parsed? {
+        let lines = body.components(separatedBy: .newlines)
+        guard let first = lines.first,
+              first.trimmingCharacters(in: .whitespaces).hasPrefix(">") else { return nil }
+
+        var quoteLines: [String] = []
+        var bodyStart = 0
+        for (index, line) in lines.enumerated() {
+            let trimmed = line.trimmingCharacters(in: .whitespaces)
+            if trimmed.hasPrefix(">") {
+                quoteLines.append(String(trimmed.dropFirst()).trimmingCharacters(in: .whitespaces))
+                bodyStart = index + 1
+                continue
+            }
+            if trimmed.isEmpty, !quoteLines.isEmpty {
+                bodyStart = index + 1
+                continue
+            }
+            break
+        }
+
+        guard !quoteLines.isEmpty, bodyStart < lines.count else { return nil }
+        let remaining = lines[bodyStart...]
+            .joined(separator: "\n")
+            .trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !remaining.isEmpty else { return nil }
+        return Parsed(body: remaining, preview: normalizedPreview(quoteLines))
+    }
+
+    private static func quotePreview(from fallback: String) -> String? {
+        let lines = fallback.components(separatedBy: .newlines).compactMap { line -> String? in
+            let trimmed = line.trimmingCharacters(in: .whitespaces)
+            guard trimmed.hasPrefix(">") else { return nil }
+            return String(trimmed.dropFirst()).trimmingCharacters(in: .whitespaces)
+        }
+        return normalizedPreview(lines)
+    }
+
+    private static func normalizedPreview(_ lines: [String]) -> String? {
+        var values = lines.filter { !$0.isEmpty }
+        if values.count > 1,
+           let first = values.first?.lowercased(),
+           first.hasSuffix(":") || first.contains(" wrote") || first.contains("написал") {
+            values.removeFirst()
+        }
+        let value = values.joined(separator: "\n")
+            .trimmingCharacters(in: .whitespacesAndNewlines)
+        guard !value.isEmpty else { return nil }
+        return value.count > 280 ? String(value.prefix(277)) + "…" : value
+    }
+
+    private static func scalarSubstring(_ value: String, start: Int, end: Int) -> String? {
+        let scalars = value.unicodeScalars
+        guard start >= 0, end >= start, end <= scalars.count else { return nil }
+        let lower = scalars.index(scalars.startIndex, offsetBy: start)
+        let upper = scalars.index(scalars.startIndex, offsetBy: end)
+        return String(value[lower..<upper])
+    }
+
+    private static func removingScalarRange(_ value: String, start: Int, end: Int) -> String? {
+        let scalars = value.unicodeScalars
+        guard start >= 0, end >= start, end <= scalars.count else { return nil }
+        let lower = scalars.index(scalars.startIndex, offsetBy: start)
+        let upper = scalars.index(scalars.startIndex, offsetBy: end)
+        return String(value[..<lower]) + String(value[upper...])
+    }
+}