import AppKit
import ConjureKit
import Testing

@Test @MainActor
func notesRoundTripIndependentMarkdownUnicodeAndImageContents() throws {
    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    defer { try? FileManager.default.removeItem(at: directory) }
    let store = try NotesStore(directory: directory)
    let firstID = try store.create()
    let secondID = try store.create()
    #expect(store.notes.count == 2)
    #expect(store.notes.allSatisfy { $0.title == "Untitled Note" })

    let bitmap = try #require(NSBitmapImageRep(
        bitmapDataPlanes: nil, pixelsWide: 1, pixelsHigh: 1,
        bitsPerSample: 8, samplesPerPixel: 4, hasAlpha: true, isPlanar: false,
        colorSpaceName: .deviceRGB, bytesPerRow: 0, bitsPerPixel: 0
    ))
    bitmap.setColor(.red, atX: 0, y: 0)
    let png = try #require(bitmap.representation(using: .png, properties: [:]))
    let imageFile = FileWrapper(regularFileWithContents: png)
    imageFile.preferredFilename = "pixel.png"
    let attachment = NSTextAttachment(fileWrapper: imageFile)
    let first = NSMutableAttributedString(attributedString: NoteDocument.importMarkdown(NSAttributedString(string: "\n  # 日本語 🦊  \n**bold** and `code`\n")))
    first.append(NSAttributedString(attachment: attachment))
    let expectedFirstText = first.string
    try store.update(id: firstID, contents: first)
    first.mutableString.setString("Mutated caller buffer")
    #expect(store.notes.first { $0.id == firstID }?.contents.string == expectedFirstText)
    #expect(store.notes.first { $0.id == firstID }?.title == "日本語 🦊")

    try store.update(id: secondID, contents: NSAttributedString(string: "Second note"))
    try store.update(id: secondID, contents: NoteDocument.importMarkdown(NSAttributedString(string: "## Edited\n- café\n- Ελληνικά")))
    #expect(store.notes.first { $0.id == firstID }?.contents.string == expectedFirstText)

    let reloaded = try NotesStore(directory: directory)
    #expect(Set(reloaded.notes.map(\.id)) == Set([firstID, secondID]))
    let restoredFirst = try #require(reloaded.notes.first { $0.id == firstID })
    #expect(restoredFirst.contents.string == expectedFirstText)
    #expect(restoredFirst.title == "日本語 🦊")
    let restoredAttachment = try #require(restoredFirst.contents.attribute(
        .attachment, at: restoredFirst.contents.length - 1, effectiveRange: nil
    ) as? NSTextAttachment)
    let restoredPNG = try #require(restoredAttachment.fileWrapper?.regularFileContents)
    #expect(restoredPNG == png)
    #expect(NSImage(data: restoredPNG) != nil)
    #expect(reloaded.notes.first { $0.id == secondID }?.contents.string == "Edited\ncafé\nΕλληνικά")
}

@Test @MainActor
func notesWriteFailuresPreserveSavedMemoryAndDiskContents() throws {
    let root = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    defer { try? FileManager.default.removeItem(at: root) }
    let directory = root.appendingPathComponent("Notes")
    let backup = root.appendingPathComponent("SavedNotes")
    let store = try NotesStore(directory: directory)
    let id = try store.create()
    try store.update(id: id, contents: NSAttributedString(string: "Saved contents"))

    // A regular file in place of the parent directory fails even when tests run as root.
    try FileManager.default.moveItem(at: directory, to: backup)
    try Data("not a directory".utf8).write(to: directory)
    #expect(throws: (any Error).self) {
        try store.update(id: id, contents: NSAttributedString(string: "Unsaved changes"))
    }
    #expect(throws: (any Error).self) { try store.create() }
    #expect(store.notes.count == 1)
    #expect(store.notes.first?.contents.string == "Saved contents")
    #expect(store.notes.first?.title == "Saved contents")

    try FileManager.default.removeItem(at: directory)
    try FileManager.default.moveItem(at: backup, to: directory)
    let reloaded = try NotesStore(directory: directory)
    #expect(reloaded.notes.first?.id == id)
    #expect(reloaded.notes.first?.contents.string == "Saved contents")
}

@Test @MainActor
func corruptPersistedNotesRaiseErrorsWithoutReplacement() throws {
    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    defer { try? FileManager.default.removeItem(at: directory) }
    let package = directory.appendingPathComponent(UUID().uuidString + ".rtfd")
    try FileManager.default.createDirectory(at: package, withIntermediateDirectories: true)
    let corruptRTF = package.appendingPathComponent("TXT.rtf")
    let bytes = Data("This is not an RTF document".utf8)
    try bytes.write(to: corruptRTF)

    #expect(throws: (any Error).self) { try NotesStore(directory: directory) }
    #expect(try Data(contentsOf: corruptRTF) == bytes)
}

@Test @MainActor
func noteTitlesUseFirstNonemptyLineAndCapAtSixtyCharacters() throws {
    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    defer { try? FileManager.default.removeItem(at: directory) }
    let store = try NotesStore(directory: directory)
    let id = try store.create()
    try store.update(id: id, contents: NSAttributedString(string: "\n \t\n  " + String(repeating: "🦊", count: 70) + "  \nIgnored"))
    #expect(store.notes.first?.title == String(repeating: "🦊", count: 60))
    try store.update(id: id, contents: NSAttributedString(string: " \t\n\n"))
    #expect(store.notes.first?.title == "Untitled Note")
}

@Test @MainActor
func deletingNotesPersistsWithoutChangingOtherNotesAndPreservesMemoryOnFailure() throws {
    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    let backup = directory.appendingPathExtension("backup")
    defer {
        try? FileManager.default.removeItem(at: directory)
        try? FileManager.default.removeItem(at: backup)
    }
    let store = try NotesStore(directory: directory)
    let deleted = try store.create()
    let kept = try store.create()
    try store.update(id: kept, contents: NSAttributedString(string: "Keep this note"))
    try store.delete(id: deleted)
    #expect(store.notes.map(\.id) == [kept])
    #expect(try NotesStore(directory: directory).notes.map(\.id) == [kept])
    #expect(throws: (any Error).self) { try store.delete(id: deleted) }

    try FileManager.default.moveItem(at: directory, to: backup)
    try Data("Blocked storage".utf8).write(to: directory)
    #expect(throws: (any Error).self) { try store.delete(id: kept) }
    #expect(store.notes.map(\.id) == [kept])
    #expect(store.notes.first?.contents.string == "Keep this note")
    try FileManager.default.removeItem(at: directory)
    try FileManager.default.moveItem(at: backup, to: directory)
    #expect(try NotesStore(directory: directory).notes.first?.contents.string == "Keep this note")
    try store.delete(id: kept)
    #expect(store.notes.isEmpty)
    #expect(try NotesStore(directory: directory).notes.isEmpty)
}

@Test @MainActor
func legacyNotesConvertWithoutWritingAndBackUpOriginalPackageOnlyOnFirstSave() throws {
    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    defer { try? FileManager.default.removeItem(at: directory) }
    try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true)
    let id = UUID()
    let url = directory.appendingPathComponent(id.uuidString + ".rtfd")
    let legacy = NSMutableAttributedString(string: "# Heading\n- [ ] task\n**bold** and `code`\n")
    let bitmap = try #require(NSBitmapImageRep(bitmapDataPlanes: nil, pixelsWide: 1, pixelsHigh: 1, bitsPerSample: 8, samplesPerPixel: 4, hasAlpha: true, isPlanar: false, colorSpaceName: .deviceRGB, bytesPerRow: 0, bitsPerPixel: 0))
    bitmap.setColor(.blue, atX: 0, y: 0)
    let png = try #require(bitmap.representation(using: .png, properties: [:]))
    let image = FileWrapper(regularFileWithContents: png)
    image.preferredFilename = "legacy.png"
    legacy.append(NSAttributedString(attachment: NSTextAttachment(fileWrapper: image)))
    let wrapper = try legacy.fileWrapper(from: NSRange(location: 0, length: legacy.length), documentAttributes: [.documentType: NSAttributedString.DocumentType.rtfd])
    try wrapper.write(to: url, options: .atomic, originalContentsURL: nil)
    let originalRTF = try Data(contentsOf: url.appendingPathComponent("TXT.rtf"))
    let store = try NotesStore(directory: directory)
    let note = try #require(store.notes.first)
    #expect(note.contents.string == "Heading\ntask\nbold and code\n\u{fffc}")
    #expect(note.title == "Heading")
    #expect(try Data(contentsOf: url.appendingPathComponent("TXT.rtf")) == originalRTF)
    #expect(!FileManager.default.fileExists(atPath: url.appendingPathComponent("ConjureNote.json").path))
    #expect(!FileManager.default.fileExists(atPath: directory.appendingPathComponent("LegacyBackups").path))

    try store.update(id: id, contents: note.contents)
    let backup = directory.appendingPathComponent("LegacyBackups").appendingPathComponent(id.uuidString + ".rtfd")
    #expect(try Data(contentsOf: backup.appendingPathComponent("TXT.rtf")) == originalRTF)
    #expect(try Data(contentsOf: backup.appendingPathComponent("legacy.png")) == png)
    #expect(!FileManager.default.fileExists(atPath: backup.appendingPathComponent("ConjureNote.json").path))
    #expect(FileManager.default.fileExists(atPath: url.appendingPathComponent("ConjureNote.json").path))
    let reloaded = try NotesStore(directory: directory)
    #expect(reloaded.notes.first?.contents.string == note.contents.string)
    let restored = try #require(reloaded.notes.first?.contents)
    let attachment = try #require(restored.attribute(.attachment, at: restored.length - 1, effectiveRange: nil) as? NSTextAttachment)
    #expect(attachment.fileWrapper?.regularFileContents == png)
    try reloaded.update(id: id, contents: NSAttributedString(string: "Changed"))
    #expect(try Data(contentsOf: backup.appendingPathComponent("TXT.rtf")) == originalRTF)
    #expect(try FileManager.default.contentsOfDirectory(atPath: directory.appendingPathComponent("LegacyBackups").path) == [id.uuidString + ".rtfd"])
}

@Test @MainActor
func failedLegacyBackupBlocksMigrationAndPreservesMemoryAndOriginalSource() throws {
    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    defer { try? FileManager.default.removeItem(at: directory) }
    try FileManager.default.createDirectory(at: directory, withIntermediateDirectories: true)
    let id = UUID()
    let url = directory.appendingPathComponent(id.uuidString + ".rtfd")
    let source = NSAttributedString(string: "## Original")
    let wrapper = try source.fileWrapper(from: NSRange(location: 0, length: source.length), documentAttributes: [.documentType: NSAttributedString.DocumentType.rtfd])
    try wrapper.write(to: url, options: .atomic, originalContentsURL: nil)
    let original = try Data(contentsOf: url.appendingPathComponent("TXT.rtf"))
    let store = try NotesStore(directory: directory)
    let blocker = directory.appendingPathComponent("LegacyBackups")
    try Data("not a directory".utf8).write(to: blocker)
    #expect(throws: (any Error).self) { try store.update(id: id, contents: NSAttributedString(string: "Unsaved")) }
    #expect(store.notes.first?.contents.string == "Original")
    #expect(try Data(contentsOf: url.appendingPathComponent("TXT.rtf")) == original)
    #expect(!FileManager.default.fileExists(atPath: url.appendingPathComponent("ConjureNote.json").path))
    try FileManager.default.removeItem(at: blocker)
    try store.update(id: id, contents: NSAttributedString(string: "Saved"))
    #expect(try NotesStore(directory: directory).notes.first?.contents.string == "Saved")
}

@Test @MainActor
func corruptStructuredMetadataIsNeverReinterpretedAsLegacyMarkdown() throws {
    let directory = FileManager.default.temporaryDirectory.appendingPathComponent(UUID().uuidString)
    defer { try? FileManager.default.removeItem(at: directory) }
    let store = try NotesStore(directory: directory)
    let id = try store.create()
    try store.update(id: id, contents: NSAttributedString(string: "# literal"))
    let package = directory.appendingPathComponent(id.uuidString + ".rtfd")
    let metadata = package.appendingPathComponent("ConjureNote.json")
    let corrupt = Data("invalid json".utf8)
    try corrupt.write(to: metadata)
    let originalRTF = try Data(contentsOf: package.appendingPathComponent("TXT.rtf"))
    #expect(throws: NoteDocument.DocumentError.self) { try NotesStore(directory: directory) }
    #expect(try Data(contentsOf: metadata) == corrupt)
    #expect(try Data(contentsOf: package.appendingPathComponent("TXT.rtf")) == originalRTF)
    #expect(!FileManager.default.fileExists(atPath: directory.appendingPathComponent("LegacyBackups").path))
}