//
//  ClipStore.swift
//  Note
//
//  Created by Kimi Code CLI on 2026/7/15.
//

import Foundation

struct Clip: Codable, Identifiable, Equatable, Sendable {
    let id: UUID
    var text: String
    let createdAt: Date
    var source: String?

    nonisolated init(id: UUID = UUID(), text: String, createdAt: Date = Date(), source: String? = nil) {
        self.id = id
        self.text = text
        self.createdAt = createdAt
        self.source = source
    }
}

actor ClipStore {

    static let shared = ClipStore()

    private let appGroupIdentifier = "group.com.fishestlife.note"
    private let fileName = "clips.json"
    private let subdirectory = "SharedFiles/Clips"

    private var cachedClips: [Clip]?

    private var fileURL: URL {
        let fileManager = FileManager.default
        guard let containerURL = fileManager.containerURL(forSecurityApplicationGroupIdentifier: appGroupIdentifier) else {
            fatalError("无法访问 App Group 容器: \(appGroupIdentifier)")
        }
        let directoryURL = containerURL.appendingPathComponent(subdirectory, isDirectory: true)
        try? fileManager.createDirectory(at: directoryURL, withIntermediateDirectories: true)
        return directoryURL.appendingPathComponent(fileName)
    }

    private init() {}

    func save(text: String, source: String? = nil) async throws {
        var clips = try await loadAll()
        let clip = Clip(text: text, source: source)
        clips.insert(clip, at: 0)
        try await persist(clips)
    }

    func loadAll() async throws -> [Clip] {
        if let cached = cachedClips {
            return cached
        }

        let url = fileURL
        let fileManager = FileManager.default
        guard fileManager.fileExists(atPath: url.path) else {
            cachedClips = []
            return []
        }

        let data = try Data(contentsOf: url)
        let clips = try JSONDecoder().decode([Clip].self, from: data)
        cachedClips = clips
        return clips
    }

    func delete(id: UUID) async throws {
        var clips = try await loadAll()
        clips.removeAll { $0.id == id }
        try await persist(clips)
    }

    func clearAll() async throws {
        try await persist([])
    }

    func count() async throws -> Int {
        let clips = try await loadAll()
        return clips.count
    }

    private func persist(_ clips: [Clip]) async throws {
        let url = fileURL
        let data = try JSONEncoder().encode(clips)
        try data.write(to: url, options: .atomic)
        cachedClips = clips
    }
}