import Foundation

/// 崩溃文件持久化
enum LogStorage {

    private static let crashDir = "xuqm_bugcollect_crashes"
    private static let encoder: JSONEncoder = {
        let e = JSONEncoder()
        e.dateEncodingStrategy = .iso8601
        return e
    }()

    /// 保存崩溃到磁盘
    static func saveCrash(_ event: IssueEvent) {
        let dir = crashDirectory()
        try? FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true)

        let filename = "\(Int(Date().timeIntervalSince1970))_\(event.fingerprint.prefix(8)).json"
        let url = dir.appendingPathComponent(filename)

        if let data = try? encoder.encode(event) {
            try? data.write(to: url)
        }
    }

    /// 加载待处理的崩溃
    static func loadPendingCrashes() -> [IssueEvent] {
        let dir = crashDirectory()
        guard let files = try? FileManager.default.contentsOfDirectory(
            at: dir,
            includingPropertiesForKeys: nil
        ) else { return [] }

        let decoder = JSONDecoder()
        decoder.dateDecodingStrategy = .iso8601

        return files
            .filter { $0.pathExtension == "json" }
            .compactMap { url -> IssueEvent? in
                guard let data = try? Data(contentsOf: url) else { return nil }
                return try? decoder.decode(IssueEvent.self, from: data)
            }
    }

    /// 清除已上传的崩溃
    static func clearPendingCrashes() {
        let dir = crashDirectory()
        guard let files = try? FileManager.default.contentsOfDirectory(
            at: dir,
            includingPropertiesForKeys: nil
        ) else { return }

        for file in files {
            try? FileManager.default.removeItem(at: file)
        }
    }

    private static func crashDirectory() -> URL {
        let caches = FileManager.default.urls(for: .cachesDirectory, in: .userDomainMask).first!
        return caches.appendingPathComponent(crashDir)
    }
}