//
//  HostVersionCheck.swift
//  MioIsland AirDrop Plugin
//
//  Gates the plugin against a minimum host version. Plugin relies on
//  the v2.2.0 panel-sizing rules (min height 120, floating back chip,
//  no chrome header), so older hosts would render this plugin wrong.
//

import Foundation

enum HostVersionCheck {
    static let minHost = "2.2.0"

    /// Bundle.main inside a plugin dylib points to the *host* app, so
    /// we can read its CFBundleShortVersionString to gate features.
    static func isOK() -> Bool {
        let host = Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String ?? "0.0.0"
        return compare(host, ">=", minHost)
    }

    static func hostVersion() -> String {
        Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String ?? "?"
    }

    // MARK: - Pure semver compare

    private static func compare(_ a: String, _ op: String, _ b: String) -> Bool {
        let aParts = parts(a)
        let bParts = parts(b)
        let maxLen = max(aParts.count, bParts.count)
        let ap = aParts + Array(repeating: 0, count: maxLen - aParts.count)
        let bp = bParts + Array(repeating: 0, count: maxLen - bParts.count)

        switch op {
        case ">=": return !ap.lexicographicallyPrecedes(bp)
        case "<":  return ap.lexicographicallyPrecedes(bp)
        case "==": return ap == bp
        default:   return false
        }
    }

    private static func parts(_ s: String) -> [Int] {
        s.split(separator: ".").compactMap { Int($0) }
    }
}