import Foundation

/// Routet sowohl Custom-Scheme- (`zitare://`) als auch Universal-Link-URLs
/// (`zitare.com/...`) auf eine konkrete `WebTarget` + Ziel-Tab.
///
/// Pure-Logic, kein State — easy testbar.
enum DeepLinkRouter {
    /// Mapt eine externe URL auf eine WebShell-URL.
    /// `zitare://quote/x` → `https://zitare.com/q/x`,
    /// `zitare://author/x` → `https://zitare.com/a/x`,
    /// `zitare://collection/x` → `https://zitare.com/c/x`.
    /// `https://*` bleibt unverändert.
    static func resolveToWebURL(_ url: URL, base: URL) -> URL {
        if url.scheme == "zitare" {
            let host = url.host ?? ""
            let path = url.path
            switch host {
            case "quote": return base.appendingPathComponent("q\(path)")
            case "author": return base.appendingPathComponent("a\(path)")
            case "collection": return base.appendingPathComponent("c\(path)")
            default: return base
            }
        }
        return url
    }

    /// `true` wenn der Pfad in den Erkunden-Tab gehört. Sonst Lesen-Tab.
    static func isExplorePath(_ path: String) -> Bool {
        let prefixes = ["/explore", "/region", "/thema", "/rolle", "/epoche", "/sprache", "/search", "/t"]
        return prefixes.contains { path == $0 || path.hasPrefix($0 + "/") }
    }

    /// One-Shot-Resolution: URL + Base → (resolvedURL, isExploreTab).
    static func route(_ url: URL, base: URL) -> (url: URL, isExplore: Bool) {
        let resolved = resolveToWebURL(url, base: base)
        return (resolved, isExplorePath(resolved.path))
    }
}