import SwiftUI
import AppIntents
import Bedrock

@main
struct BusinessCardClipApp: App {
    @State private var recordName: String?
    @State private var launchErrorMessage: String?
    #if DEBUG
    @State private var debugState: ClipDebugState?
    #endif

    var body: some Scene {
        WindowGroup {
            Group {
                #if DEBUG
                if let debugState {
                    ClipDebugHarnessView(initialState: debugState)
                } else if let recordName {
                    ClipRootView(recordName: recordName)
                } else if let launchErrorMessage {
                    ClipErrorView(message: launchErrorMessage) {
                        self.launchErrorMessage = nil
                    }
                } else {
                    ClipLoadingView()
                }
                #else
                if let recordName {
                    ClipRootView(recordName: recordName)
                } else if let launchErrorMessage {
                    ClipErrorView(message: launchErrorMessage) {
                        self.launchErrorMessage = nil
                    }
                } else {
                    ClipLoadingView()
                }
                #endif
            }
            .onContinueUserActivity(NSUserActivityTypeBrowsingWeb) { activity in
                Design.debugLog("Clip: onContinueUserActivity fired, webpageURL=\(activity.webpageURL?.absoluteString ?? "nil")")
                handleUserActivity(activity)
            }
            .onOpenURL { url in
                Design.debugLog("Clip: onOpenURL fired, url=\(url.absoluteString)")
                handleURL(url)
            }
            .task {
                Design.debugLog("Clip: .task running - checking launch sources")
                #if DEBUG
                if let dbg = parseDebugStateArgument() {
                    Design.debugLog("Clip: debug state from args: \(dbg.rawValue)")
                    debugState = dbg
                    return
                }
                #endif
                if let envURL = ProcessInfo.processInfo.environment["_XCAppClipURL"],
                   let url = URL(string: envURL) {
                    Design.debugLog("Clip: _XCAppClipURL from env: \(envURL)")
                    handleURL(url)
                } else {
                    Design.debugLog("Clip: no _XCAppClipURL in env, no debug args. recordName=\(recordName ?? "nil")")
                }
            }
        }
    }

    private func handleUserActivity(_ activity: NSUserActivity) {
        Design.debugLog("Clip: handleUserActivity, webpageURL=\(activity.webpageURL?.absoluteString ?? "nil")")
        guard let url = activity.webpageURL else {
            Design.debugLog("Clip: handleUserActivity - no webpageURL, skipping")
            return
        }
        handleURL(url)
    }

    private func handleURL(_ url: URL) {
        Design.debugLog("Clip: handleURL \(url.absoluteString)")
        guard let id = extractRecordName(from: url) else {
            Design.debugLog("Clip: extractRecordName failed for \(url.absoluteString)")
            launchErrorMessage = ClipError.invalidRecord.localizedDescription
            return
        }
        Design.debugLog("Clip: extracted recordName=\(id), setting recordName")
        launchErrorMessage = nil
        recordName = id
    }
    
    private func extractRecordName(from url: URL) -> String? {
        if let components = URLComponents(url: url, resolvingAgainstBaseURL: true),
           let id = components.queryItems?
            .first(where: { $0.name == ClipDesign.URL.recordQueryName })?
            .value,
           !id.isEmpty {
            return id
        }
        
        // Fallback for path-based links (e.g. /clip/{recordName}).
        let candidate = url.lastPathComponent.trimmingCharacters(in: .whitespacesAndNewlines)
        guard !candidate.isEmpty, candidate != "/" else { return nil }
        return candidate
    }
    
    #if DEBUG
    private func parseDebugStateArgument() -> ClipDebugState? {
        let prefix = "--clip-debug="
        guard let argument = ProcessInfo.processInfo.arguments.first(where: { $0.hasPrefix(prefix) }) else {
            return nil
        }
        
        let value = String(argument.dropFirst(prefix.count))
        return ClipDebugState(rawValue: value)
    }
    #endif
}