import Foundation
import Capacitor
import AVFoundation

// Earpiece <-> speaker toggle for calls. Registered by cap sync as a real Capacitor plugin package, so it
// shows up as window.Capacitor.Plugins.AudioRoute (an app-embedded class gets stripped in release builds).
//
// THE PROBLEM (from device telemetry): overrideOutputAudioPort(.none) routes to the receiver ONCE, then the
// route latches to the built-in Speaker on every later toggle — even though the category has NO
// .defaultToSpeaker. That fingerprints WebKit's WebRTC engine re-forcing the loudspeaker AFTER our override.
// The earlier build ignored .override-reason route changes (to avoid a feedback loop) and so never corrected
// WebKit's re-force → stuck on speaker → earpiece silent.
//
// THE FIX: re-assert the chosen port AFTER each route change settles (debounced 0.25s), reacting to ALL
// changes but acting ONLY on a real mismatch — so our own override (which also fires a change) finds the
// route already correct and does nothing, terminating the loop. Capped per toggle so a persistent adversary
// can't thrash the audio. A ring-buffer route log (reason -> port) rides back in setSpeaker's result so the
// telemetry shows the exact battle.
@objc(AudioRoutePlugin)
public class AudioRoutePlugin: CAPPlugin, CAPBridgedPlugin {
    public let identifier = "AudioRoutePlugin"
    public let jsName = "AudioRoute"
    public let pluginMethods: [CAPPluginMethod] = [
        CAPPluginMethod(name: "setSpeaker", returnType: CAPPluginReturnPromise)
    ]

    // Bump on every native change so telemetry identifies the running binary unambiguously.
    private static let nativeTag = "1.0.3-reassert"

    private var wantSpeaker = false          // desired output; source of truth, re-applied on route changes
    private var pending: DispatchWorkItem?   // debounced re-assert
    private var asserts = 0                   // re-assert count this toggle (capped, anti-thrash)
    private var routeLog: [String] = []       // reason->port trail, returned to JS for diagnosis

    override public func load() {
        let session = AVAudioSession.sharedInstance()
        // NO .defaultToSpeaker — the port is driven explicitly so .none means the earpiece/receiver.
        try? session.setCategory(.playAndRecord, mode: .voiceChat, options: [.allowBluetooth, .allowBluetoothA2DP])
        try? session.setActive(true)
        NotificationCenter.default.addObserver(self, selector: #selector(routeChanged(_:)),
                                               name: AVAudioSession.routeChangeNotification, object: nil)
    }

    deinit { NotificationCenter.default.removeObserver(self) }

    private func reasonName(_ r: UInt) -> String {
        switch r {
        case 1: return "newDev"; case 2: return "oldDev"; case 3: return "catChg"
        case 4: return "override"; case 6: return "wake"; case 7: return "noRoute"
        case 8: return "cfgChg"; default: return "unknown"
        }
    }

    private func ports() -> String {
        let outs = AVAudioSession.sharedInstance().currentRoute.outputs.map { $0.portType.rawValue }
        return outs.isEmpty ? "(none)" : outs.joined(separator: "+")
    }

    private func log(_ s: String) {
        routeLog.append(s)
        if routeLog.count > 16 { routeLog.removeFirst(routeLog.count - 16) }
    }

    @objc private func routeChanged(_ note: Notification) {
        let raw = (note.userInfo?[AVAudioSessionRouteChangeReasonKey] as? UInt) ?? 0
        log("\(reasonName(raw))>\(ports())")
        // Re-assert AFTER WebKit's change settles; coalesce bursts into one late assert so we act last.
        pending?.cancel()
        let work = DispatchWorkItem { [weak self] in self?.applyRoute() }
        pending = work
        DispatchQueue.main.asyncAfter(deadline: .now() + 0.25, execute: work)
    }

    private func applyRoute() {
        guard asserts < 6 else { log("cap"); return }   // anti-thrash: give up rather than ping-pong forever
        let session = AVAudioSession.sharedInstance()
        let onSpeaker = session.currentRoute.outputs.contains { $0.portType == .builtInSpeaker }
        do {
            if wantSpeaker && !onSpeaker {
                asserts += 1; try session.overrideOutputAudioPort(.speaker); log("assert>spk")
            } else if !wantSpeaker && onSpeaker {
                asserts += 1; try session.overrideOutputAudioPort(.none); log("assert>none")
            }
        } catch { log("assertErr") }
    }

    private func diag(_ applied: String) -> [String: Any] {
        let s = AVAudioSession.sharedInstance()
        return [
            "route": applied,
            "native": AudioRoutePlugin.nativeTag,
            "outputs": ports(),
            "category": s.category.rawValue,
            "mode": s.mode.rawValue,
            "opts": Int(s.categoryOptions.rawValue),
            "log": routeLog.joined(separator: ",")   // route-change trail since the previous toggle
        ]
    }

    @objc func setSpeaker(_ call: CAPPluginCall) {
        wantSpeaker = call.getBool("on") ?? true
        asserts = 0
        let session = AVAudioSession.sharedInstance()
        do {
            try session.overrideOutputAudioPort(wantSpeaker ? .speaker : .none)
            let out = diag(wantSpeaker ? "speaker" : "earpiece")
            routeLog.removeAll()   // reset the trail; next toggle reports what happened in between
            call.resolve(out)
        } catch {
            call.reject(error.localizedDescription)
        }
    }
}