Files
Sybil-2/ios/Packages/Sybil/Sources/Sybil/SybilChatAttachmentSupport.swift

355 lines
13 KiB
Swift

import Foundation
import UniformTypeIdentifiers
import UIKit
enum ChatAttachmentError: LocalizedError {
case unsupportedType(String)
case imageTooLarge(String)
case textTooLarge(String)
case unreadableFile(String)
case unsupportedImageFormat(String)
case tooManyAttachments(Int)
var errorDescription: String? {
switch self {
case let .unsupportedType(filename):
return "Unsupported file type for '\(filename)'. Use PNG/JPEG images or text-based files."
case let .imageTooLarge(filename):
return "Image '\(filename)' exceeds the 6 MB upload limit."
case let .textTooLarge(filename):
return "Text file '\(filename)' exceeds the 8 MB upload limit."
case let .unreadableFile(filename):
return "Could not read '\(filename)'."
case let .unsupportedImageFormat(filename):
return "Image '\(filename)' could not be converted to PNG or JPEG."
case let .tooManyAttachments(limit):
return "You can attach up to \(limit) files per message."
}
}
}
enum SybilChatAttachmentSupport {
static let maxAttachmentsPerMessage = 8
static let maxImageBytes = 6 * 1024 * 1024
static let maxTextBytes = 8 * 1024 * 1024
static let maxTextCharacters = 200_000
private static let supportedTextExtensions: Set<String> = [
"txt", "md", "markdown", "csv", "tsv", "json", "jsonl", "xml", "yaml", "yml", "html", "htm",
"css", "js", "jsx", "ts", "tsx", "py", "rb", "java", "c", "cc", "cpp", "h", "hpp", "go",
"rs", "sh", "sql", "log", "toml", "ini", "cfg", "conf", "swift", "kt", "m", "mm"
]
private static let supportedTextMimeTypes: Set<String> = [
"application/json",
"application/ld+json",
"application/sql",
"application/toml",
"application/x-httpd-php",
"application/x-javascript",
"application/x-sh",
"application/xml",
"application/yaml",
"application/x-yaml",
"image/svg+xml"
]
static func attachmentSummary(_ attachments: [ChatAttachment]) -> String {
guard !attachments.isEmpty else { return "" }
let names = attachments.map(\.filename).joined(separator: ", ")
return attachments.count == 1 ? names : "Attached: \(names)"
}
static func metadataValue(for attachments: [ChatAttachment]) -> JSONValue? {
guard !attachments.isEmpty else { return nil }
return .object([
"attachments": .array(attachments.map(\.jsonValue))
])
}
static func buildAttachments(from urls: [URL]) throws -> [ChatAttachment] {
try urls.map { try buildAttachment(fromFileURL: $0) }
}
static func buildImageAttachment(image: UIImage, filename: String = "pasted-image.jpg") throws -> ChatAttachment {
if let pngData = image.pngData(), pngData.count <= maxImageBytes {
return try buildImageAttachment(data: pngData, filename: filename, contentType: .png)
}
guard let jpegData = image.jpegData(compressionQuality: 0.92) else {
throw ChatAttachmentError.unsupportedImageFormat(filename)
}
return try buildImageAttachment(data: jpegData, filename: filename, contentType: .jpeg)
}
static func buildTextAttachment(text: String, filename: String = "pasted-text.txt", mimeType: String = "text/plain") throws -> ChatAttachment {
let data = Data(text.utf8)
return try buildTextAttachment(data: data, filename: filename, mimeType: mimeType)
}
@MainActor
static func buildAttachments(from itemProviders: [NSItemProvider]) async throws -> [ChatAttachment] {
var attachments: [ChatAttachment] = []
for provider in itemProviders {
if let fileURL = try await loadFileURL(from: provider) {
attachments.append(try buildAttachment(fromFileURL: fileURL))
continue
}
if provider.hasItemConformingToTypeIdentifier(UTType.image.identifier) {
if let attachment = try await loadImageAttachment(from: provider) {
attachments.append(attachment)
}
}
}
return attachments
}
static func previewText(for attachment: ChatAttachment) -> String {
let normalized = (attachment.text ?? "")
.replacingOccurrences(of: "\r", with: "")
.trimmingCharacters(in: .whitespacesAndNewlines)
if normalized.isEmpty {
return "(empty file)"
}
if normalized.count <= 280 {
return normalized
}
let endIndex = normalized.index(normalized.startIndex, offsetBy: 280)
return normalized[..<endIndex].trimmingCharacters(in: .whitespacesAndNewlines) + "..."
}
static func image(for attachment: ChatAttachment) -> UIImage? {
guard attachment.kind == .image,
let dataURL = attachment.dataUrl,
let data = decodeDataURL(dataURL)
else {
return nil
}
return UIImage(data: data)
}
private static func buildAttachment(fromFileURL url: URL) throws -> ChatAttachment {
let accessed = url.startAccessingSecurityScopedResource()
defer {
if accessed {
url.stopAccessingSecurityScopedResource()
}
}
let filename = url.lastPathComponent.isEmpty ? "attachment" : url.lastPathComponent
let resourceValues = try? url.resourceValues(forKeys: [.contentTypeKey])
let contentType = resourceValues?.contentType ?? UTType(filenameExtension: url.pathExtension)
let data: Data
do {
data = try Data(contentsOf: url)
} catch {
throw ChatAttachmentError.unreadableFile(filename)
}
if contentType?.conforms(to: .image) == true {
return try buildImageAttachment(data: data, filename: filename, contentType: contentType)
}
if isTextLike(contentType: contentType, mimeType: contentType?.preferredMIMEType, filename: filename) {
return try buildTextAttachment(data: data, filename: filename, mimeType: contentType?.preferredMIMEType ?? "text/plain")
}
throw ChatAttachmentError.unsupportedType(filename)
}
static func buildImageAttachment(data: Data, filename: String, contentType: UTType?) throws -> ChatAttachment {
var mimeType = contentType?.preferredMIMEType
var payload = data
if mimeType != "image/png" && mimeType != "image/jpeg" {
guard let image = UIImage(data: data) else {
throw ChatAttachmentError.unsupportedImageFormat(filename)
}
if let pngData = image.pngData(), pngData.count <= maxImageBytes {
payload = pngData
mimeType = "image/png"
} else if let jpegData = image.jpegData(compressionQuality: 0.92) {
payload = jpegData
mimeType = "image/jpeg"
} else {
throw ChatAttachmentError.unsupportedImageFormat(filename)
}
}
if payload.count > maxImageBytes {
throw ChatAttachmentError.imageTooLarge(filename)
}
let normalizedMimeType = (mimeType == "image/png") ? "image/png" : "image/jpeg"
let dataUrl = "data:\(normalizedMimeType);base64,\(payload.base64EncodedString())"
return .image(
filename: filename,
mimeType: normalizedMimeType,
sizeBytes: payload.count,
dataUrl: dataUrl
)
}
private static func buildTextAttachment(data: Data, filename: String, mimeType: String) throws -> ChatAttachment {
if data.count > maxTextBytes {
throw ChatAttachmentError.textTooLarge(filename)
}
let normalized = String(decoding: data, as: UTF8.self)
.replacingOccurrences(of: "\r\n", with: "\n")
.replacingOccurrences(of: "\u{0000}", with: "")
let truncated = normalized.count > maxTextCharacters
let trimmedText: String
if truncated {
let endIndex = normalized.index(normalized.startIndex, offsetBy: maxTextCharacters)
trimmedText = String(normalized[..<endIndex])
} else {
trimmedText = normalized
}
return .text(
filename: filename,
mimeType: mimeType,
sizeBytes: data.count,
text: trimmedText,
truncated: truncated
)
}
private static func isTextLike(contentType: UTType?, mimeType: String?, filename: String) -> Bool {
if let contentType {
if contentType.conforms(to: .text) || contentType.conforms(to: .plainText) || contentType.conforms(to: .sourceCode) {
return true
}
if contentType.conforms(to: .json) || contentType.conforms(to: .xml) {
return true
}
}
if let mimeType {
if mimeType.hasPrefix("text/") {
return true
}
if supportedTextMimeTypes.contains(mimeType.lowercased()) {
return true
}
}
let ext = URL(fileURLWithPath: filename).pathExtension.lowercased()
return supportedTextExtensions.contains(ext)
}
private static func decodeDataURL(_ value: String) -> Data? {
guard let separator = value.firstIndex(of: ",") else {
return nil
}
let encoded = value[value.index(after: separator)...]
return Data(base64Encoded: String(encoded))
}
@MainActor
private static func loadFileURL(from provider: NSItemProvider) async throws -> URL? {
guard provider.hasItemConformingToTypeIdentifier(UTType.fileURL.identifier) else {
return nil
}
return try await withCheckedThrowingContinuation { continuation in
provider.loadItem(forTypeIdentifier: UTType.fileURL.identifier, options: nil) { item, error in
if let error {
continuation.resume(throwing: error)
return
}
if let url = item as? URL {
continuation.resume(returning: url)
return
}
if let data = item as? Data,
let url = URL(dataRepresentation: data, relativeTo: nil) {
continuation.resume(returning: url)
return
}
if let string = item as? String,
let url = URL(string: string) {
continuation.resume(returning: url)
return
}
continuation.resume(returning: nil)
}
}
}
@MainActor
private static func loadImageAttachment(from provider: NSItemProvider) async throws -> ChatAttachment? {
let preferredImageType: UTType = if provider.hasItemConformingToTypeIdentifier(UTType.png.identifier) {
.png
} else if provider.hasItemConformingToTypeIdentifier(UTType.jpeg.identifier) {
.jpeg
} else {
.image
}
if let data = try await loadDataRepresentation(from: provider, type: preferredImageType) {
let filenameExtension = preferredImageType.preferredFilenameExtension ?? "jpg"
let filename = "pasted-image.\(filenameExtension)"
return try buildImageAttachment(data: data, filename: filename, contentType: preferredImageType)
}
if let image = try await loadUIImage(from: provider),
let jpegData = image.jpegData(compressionQuality: 0.92) {
return try buildImageAttachment(data: jpegData, filename: "pasted-image.jpg", contentType: .jpeg)
}
return nil
}
@MainActor
private static func loadDataRepresentation(from provider: NSItemProvider, type: UTType) async throws -> Data? {
guard provider.hasItemConformingToTypeIdentifier(type.identifier) else {
return nil
}
return try await withCheckedThrowingContinuation { continuation in
provider.loadDataRepresentation(forTypeIdentifier: type.identifier) { data, error in
if let error {
continuation.resume(throwing: error)
return
}
continuation.resume(returning: data)
}
}
}
@MainActor
private static func loadUIImage(from provider: NSItemProvider) async throws -> UIImage? {
guard provider.canLoadObject(ofClass: UIImage.self) else {
return nil
}
return try await withCheckedThrowingContinuation { continuation in
provider.loadObject(ofClass: UIImage.self) { object, error in
if let error {
continuation.resume(throwing: error)
return
}
continuation.resume(returning: object as? UIImage)
}
}
}
}