import Foundation

public struct VersionInfo: Equatable {
    public let version: String
    /// 命令类型标识，设备可能返回 Int (如 7) 或 String (如 "0x07")
    public let type: String
    /// 设备运行日志，BLE 响应中 `log` 字段对应的任意 JSON 对象；缺失/非对象时为 nil。
    /// SDK 不解析其内部结构，原样透传给 `update-metadata` 接口。
    public let log: [String: Any]?

    public init(version: String, type: String, log: [String: Any]? = nil) {
        self.version = version
        self.type = type
        self.log = log
    }

    public static func == (lhs: VersionInfo, rhs: VersionInfo) -> Bool {
        guard lhs.version == rhs.version, lhs.type == rhs.type else { return false }
        return NSDictionary(dictionary: lhs.log ?? [:]).isEqual(to: rhs.log ?? [:])
    }
}

extension VersionInfo {
    /// 从设备 BLE 响应字节流（已剥离 0 字节）解析。
    /// type 字段兼容 Int / String 两种返回形态；log 字段缺失/非对象时返回 nil。
    static func parse(from data: Data) throws -> VersionInfo {
        let cleaned = data.filter { $0 != 0 }
        let object = try JSONSerialization.jsonObject(with: cleaned)
        guard let json = object as? [String: Any] else {
            throw DuooomiBleError.transferFailed("VersionInfo: top-level not an object")
        }

        let version = (json["version"] as? String) ?? ""

        let type: String
        if let s = json["type"] as? String {
            type = s
        } else if let n = json["type"] as? NSNumber {
            type = "\(n.intValue)"
        } else {
            type = ""
        }

        let log = json["log"] as? [String: Any]
        return VersionInfo(version: version, type: type, log: log)
    }
}