// AiNpcControl.cs
// A talking, listening, walking AI NPC. It wears one of YOUR (the scene owner's) saved outfits, follows players,
// and holds a spoken conversation powered by your own Claude or ChatGPT API key.
//
// How the pieces fit together (each is usable on its own; this script just wires them up):
//   * AiNpc      - an avatar clone (from a named outfit) the SERVER walks around: WalkTo / Follow / StopMoving,
//                  plus Say (speaks aloud to everyone nearby, quieter with distance) and Listen (one player's mic).
//   * AiBrain    - the conversation: Provider + [Secret] ApiKey + Instructions + Knowledge, Ask(text, reply => ...).
//   * CreatePanel- the little worldspace menu (Follow me / Interact) that pops up when you click the NPC.
//
// The API key is a [Secret] field: it is stored only on the server, never downloaded by players, and only you
// (the scene owner) can see or change it in the Inspector.
//
// Setup: drop this script on an empty object where the NPC should appear. Set OutfitOwner to your username and
// OutfitName to one of your saved outfits. Pick a Provider and paste the matching API key. Describe how the NPC
// should behave in Instructions, and give it facts in Knowledge. Walk up to it and click it.

using System.Collections;
using System.Collections.Generic;
using IHXR.Simulation;

public class AiNpcControl : ScriptBase
{
    public enum AiProvider { Anthropic, OpenAI }
    public enum SpeechEngine { Browser, Local }
    public enum NpcVoice { Default, Female, Male, GoogleUSEnglish, GoogleUKFemale, GoogleUKMale }

    [Header("Who the NPC is")]
    [Tooltip("The display name shown when it talks in chat.")]
    public string NpcName = "Guide";
    [Tooltip("Whose saved outfit the NPC wears. Your username (the scene owner).")]
    public string OutfitOwner = "";
    [Tooltip("The name of one of that person's outfits (Avatar Editor). Blank = the outfit they currently wear.")]
    public string OutfitName = "";
    public Vector3 SpawnOffset = new Vector3(0f, 0f, 0f);
    public Vector3 SpawnFacing = Vector3.zero;

    [Header("Brain (your own API key)")]
    public AiProvider Provider = AiProvider.Anthropic;
    [Secret]
    [Tooltip("Your Anthropic or OpenAI API key. Stored on the server only; players never receive it.")]
    public string ApiKey = "";
    [Tooltip("Model id. Light + cheap by default (good for short NPC chat). Anthropic: claude-haiku-5-5 / claude-sonnet-5-5. If you switch Provider to OpenAI it uses gpt-4o-mini automatically.")]
    public string Model = "claude-haiku-5-5";
    [Multiline(4)]
    [Tooltip("How the NPC should behave, talk and act — its personality and rules.")]
    public string Instructions = "You are a friendly, concise guide in a virtual world. Keep replies to a sentence or two, suitable for speaking aloud.";
    [Multiline(4)]
    [Tooltip("Facts the NPC may use when answering (its knowledge bank).")]
    public string Knowledge = "";
    [Range(50, 800)]
    public int MaxReplyTokens = 300;

    [Header("Voice")]
    [Tooltip("Which voice the NPC speaks with. Default = the player's system voice. Female/Male pick a matching voice on each player's device. The Google ones use those voices when present, else fall back to the default.")]
    public NpcVoice Voice = NpcVoice.Female;
    [Range(0.5f, 2f)] public float VoiceRate = 1f;
    [Range(0f, 2f)] public float VoicePitch = 1f;
    [Tooltip("How the player's speech is turned into text when they Interact. Browser = the browser's built-in recognition (fast, but streams audio to the browser's cloud). Local = a small Whisper model that runs fully in the player's browser (private, offline; a ~75MB one-time download).")]
    public SpeechEngine VoiceToText = SpeechEngine.Browser;

    [Header("Movement")]
    [Range(1f, 8f)] public float WalkSpeed = 3.5f;
    [Tooltip("How close the NPC stops when following a player.")]
    public float FollowDistance = 2f;

    [Header("Menu")]
    [Tooltip("How close you must be to click the NPC.")]
    public float ClickDistance = 14f;
    public float MenuHeight = 2.55f;
    [Range(0.4f, 3f)] public float MenuWidth = 0.9f;
    [Tooltip("Seconds the pop-up menu stays up before it fades if you don't pick anything.")]
    public float MenuIdleSeconds = 6f;

    AiNpc npc;
    AiBrain brain;
    ScriptPanel menu;
    int menuToken;
    bool interacting;
    string interactingWith = "";
    string followingWho = "";
    int interactToken;

    [Tooltip("How far (metres) the NPC looks for a seat. Any sitpoint in the scene within this range is used automatically — no need to slot any in.")]
    public float SeatSearchRange = 20f;
    [Tooltip("When a player asks what something looks like, the NPC snapshots their view and the model describes it. Max such requests per hour (0 = off).")]
    public int VisionRepliesPerHour = 6;
    bool seated;
    Sitpoint currentSeat;
    readonly List<DateTime> visionTimes = new List<DateTime>();

    public override void Start()
    {
        string owner = string.IsNullOrWhiteSpace(OutfitOwner) ? "" : OutfitOwner.Trim();
        if (owner == "")
        {
            Log("[AiNpc] Set OutfitOwner to your username (the scene owner) so the NPC knows whose outfit to wear.");
            return;
        }

        Vector3 spawnPos = transform.position + SpawnOffset;
        AvatarClone clone = SpawnAvatarClone(owner, spawnPos, SpawnFacing, Vector3.one, OutfitName);
        npc = new AiNpc(clone, spawnPos) { WalkSpeed = WalkSpeed };

        // Click the NPC itself to open the menu.
        MakeInteractable(clone, OnNpcClicked, true, null, true, ClickDistance, "Talk to " + NpcName);

        brain = new AiBrain
        {
            Provider = Provider.ToString(),
            ApiKey = ApiKey,
            Model = Model,
            Instructions = Instructions,
            Knowledge = Knowledge,
            MaxTokens = MaxReplyTokens,
        };

        // The worldspace pop-up menu (hidden until the NPC is clicked).
        menu = CreatePanel("ai-npc-menu", 300);
        menu.SetTitle(NpcName).SetLayout(1, 8, 14);
        menu.AddButton("Follow me", OnFollowClicked);
        menu.AddButton("Stop following", OnStopFollowClicked);
        menu.AddButton("Interact", OnInteractClicked);
        menu.AddButton("Sit / Stand", OnSitClicked);
        // Stand the menu above the NPC so it rides along wherever the NPC walks (not a fixed spot).
        menu.PlaceOnObject(npc.Clone, new Vector3(0f, MenuHeight, 0f), MenuWidth, true);

        if (!brain.HasKey)
            Log("[AiNpc] No API key set — the NPC can walk and follow, but can't talk until you add your key in the Inspector.");

        Log("[AiNpc] '" + NpcName + "' ready (outfit of " + owner + (OutfitName == "" ? "" : " / '" + OutfitName + "'") + ").");
    }

    void OnNpcClicked(InteractionInfo info)
    {
        if (npc == null || npc.IsNull || info == null) return;
        ShowMenuTo(info.Username);
    }

    void ShowMenuTo(string username)
    {
        if (string.IsNullOrWhiteSpace(username) || menu == null) return;
        menu.Show(username);
        // Idle fade: after MenuIdleSeconds, hide it unless another action superseded this one.
        int token = ++menuToken;
        StartCoroutine(HideMenuAfterIdle(token, username));
    }

    IEnumerator HideMenuAfterIdle(int token, string username)
    {
        yield return new WaitForSeconds(MenuIdleSeconds);
        if (token == menuToken && menu != null)
            menu.Hide(username);
    }

    void OnFollowClicked(PanelEvent e)
    {
        menuToken++; // cancels the pending idle-hide
        menu.Hide(e.Username);
        if (npc == null || npc.IsNull) return;
        if (seated) StandUp();
        followingWho = e.Username;
        npc.Follow(e.Username, FollowDistance);
        SendScriptChat(NpcName + " is now following " + e.Username + ".");
    }

    void OnStopFollowClicked(PanelEvent e)
    {
        menuToken++;
        menu.Hide(e.Username);
        if (npc == null || npc.IsNull) return;
        if (!string.IsNullOrEmpty(followingWho)) SendScriptChat(NpcName + " stopped following " + followingWho + ".");
        followingWho = "";
        npc.StopMoving();
    }

    void OnSitClicked(PanelEvent e)
    {
        menuToken++;
        menu.Hide(e.Username);
        if (npc == null || npc.IsNull) return;
        if (seated) { StandUp(); SendScriptChat(NpcName + " stood up."); return; }
        GoSitNearest(e.Username);
    }

    // Closest sitpoint in the scene to the NPC, within SeatSearchRange (found automatically — no slotting required).
    Sitpoint NearestSeat()
    {
        if (npc == null || npc.IsNull) return null;
        return NearestSitpoint(npc.Position, SeatSearchRange);
    }

    // Walk to the nearest seat and sit in it. Movement runs on the server, so every player sees the same walk + sit.
    void GoSitNearest(string username)
    {
        Sitpoint seat = NearestSeat();
        if (seat == null) { SendScriptChat(NpcName + " can't find a seat nearby."); return; }
        followingWho = "";
        currentSeat = seat;
        SendScriptChat(NpcName + " is heading to a seat.");
        // Stop ~1.4m out so the NPC halts at the edge of the seat/booth instead of grinding into it; Sit snaps it onto the seat.
        npc.WalkTo(seat.transform.position, 12f, 1.4f, ok =>
        {
            if (npc == null || npc.IsNull || !ok) return;
            npc.Sit(seat);
            seated = true;
        });
    }

    void StandUp()
    {
        if (npc == null || npc.IsNull) return;
        if (seated) npc.Stand();
        seated = false;
        currentSeat = null;
    }

    void OnInteractClicked(PanelEvent e)
    {
        menuToken++;
        menu.Hide(e.Username);
        if (npc == null || npc.IsNull) return;

        if (interacting)
        {
            // Same person clicking again (after a rejoin, or to retry): let them reclaim the conversation instead
            // of being told the NPC is "busy" with themselves. Only a DIFFERENT player is asked to wait.
            if (string.Equals(e.Username, interactingWith, System.StringComparison.OrdinalIgnoreCase))
            {
                npc.StopListening(interactingWith);
                EndInteraction();
            }
            else
            {
                SendScriptChat(NpcName + " is busy talking with " + interactingWith + " — one at a time!");
                return;
            }
        }
        if (!brain.HasKey)
        {
            SendScriptChat(NpcName + " has no API key set, so it can't chat yet.");
            return;
        }

        interacting = true;
        interactingWith = e.Username;
        int convToken = ++interactToken;
        StartCoroutine(InteractionWatchdog(convToken));

        // Stop and face the player, then listen to their microphone.
        npc.StopMoving();
        followingWho = "";
        UserInfo user = GetListener(e.Username);
        if (user != null) npc.FaceTowards(user.Position);

        npc.Listen(e.Username, heard =>
        {
            string said = (heard ?? "").Trim();
            if (said == "")
            {
                Speak("Sorry, I didn't catch that. Click Interact and try again.");
                EndInteraction();
                return;
            }

            // Everyone sees what the player said (and hears them over normal voice chat).
            SendScriptChat(e.Username + ": " + said);

            // Let the player ask the NPC, by voice, to sit down or stand up.
            string lower = said.ToLower();
            if (!seated && (lower.Contains("sit") || lower.Contains("have a seat") || lower.Contains("take a seat")))
            {
                Speak("Sure, let me grab a seat.");
                GoSitNearest(e.Username);
                EndInteraction();
                return;
            }
            if (seated && (lower.Contains("stand") || lower.Contains("get up")))
            {
                Speak("Okay, standing up.");
                StandUp();
                EndInteraction();
                return;
            }

            // Vision: if the player asks about what they're looking at, snapshot their view and let the model describe
            // it. Rate-limited (VisionRepliesPerHour); over the limit it just falls through to a normal spoken reply.
            if (IsVisionQuestion(lower) && VisionAllowed())
            {
                visionTimes.Add(DateTime.UtcNow);
                Speak("Let me take a look...");
                npc.LookAndAsk(e.Username, said, brain, reply =>
                {
                    string answer = (reply ?? "").Trim();
                    if (answer == "") answer = "Hmm, I can't quite make that out from here.";
                    SendScriptChat(NpcName + ": " + answer);
                    Speak(answer);
                    EndInteraction();
                });
                return;
            }

            brain.Ask(said, e.Username, reply =>
            {
                string answer = (reply ?? "").Trim();
                if (answer == "") answer = "Hmm, I'm not sure how to answer that.";
                SendScriptChat(NpcName + ": " + answer);
                Speak(answer);
                EndInteraction();
            });
        }, VoiceToText == SpeechEngine.Local ? "local" : "browser");
    }

    // Does the player's line ask about what they can see? (A light heuristic; tune the phrases for your world.)
    bool IsVisionQuestion(string lower)
    {
        return lower.Contains("look like") || lower.Contains("what do you see") || lower.Contains("what do u see")
            || lower.Contains("look at") || lower.Contains("take a look") || lower.Contains("what is this")
            || lower.Contains("what's this") || lower.Contains("whats this") || lower.Contains("describe what")
            || lower.Contains("what am i looking") || lower.Contains("can you see") || lower.Contains("what color");
    }

    // True while under the per-hour vision cap; also prunes entries older than an hour.
    bool VisionAllowed()
    {
        DateTime now = DateTime.UtcNow;
        visionTimes.RemoveAll(t => (now - t).TotalHours >= 1.0);
        return visionTimes.Count < Math.Max(0, VisionRepliesPerHour);
    }

    void Speak(string text)
    {
        if (npc != null && !npc.IsNull) npc.Say(text, VoiceRate, VoicePitch, VoiceName());
    }

    string VoiceName()
    {
        switch (Voice)
        {
            case NpcVoice.Female: return "female";
            case NpcVoice.Male: return "male";
            case NpcVoice.GoogleUSEnglish: return "Google US English";
            case NpcVoice.GoogleUKFemale: return "Google UK English Female";
            case NpcVoice.GoogleUKMale: return "Google UK English Male";
            default: return "";
        }
    }

    void EndInteraction()
    {
        interacting = false;
        interactingWith = "";
        interactToken++;   // cancels any pending watchdog
    }

    // Safety net: if a conversation never completes (e.g. speech-to-text returns nothing and no callback fires),
    // release the one-at-a-time lock after a while so the NPC never gets stuck "busy".
    IEnumerator InteractionWatchdog(int token)
    {
        yield return new WaitForSeconds(90f);
        if (token == interactToken && interacting)
        {
            if (!string.IsNullOrEmpty(interactingWith)) npc?.StopListening(interactingWith);
            EndInteraction();
        }
    }

    UserInfo GetListener(string username)
    {
        foreach (UserInfo u in GetUsers())
            if (u != null && string.Equals(u.Username, username, System.StringComparison.OrdinalIgnoreCase))
                return u;
        return null;
    }

    public override void OnUserJoin(UserInfo user)
    {
        // If the player who held the conversation lock left and has now rejoined (their old session is gone),
        // clear the stale lock so they — and everyone else — can interact again.
        if (user != null && interacting && string.Equals(user.Username, interactingWith, System.StringComparison.OrdinalIgnoreCase))
        {
            npc?.StopListening(interactingWith);
            EndInteraction();
        }
    }

    public override void OnUserPart(UserInfo user)
    {
        if (user == null) return;
        if (string.Equals(user.Username, followingWho, System.StringComparison.OrdinalIgnoreCase))
        {
            followingWho = "";
            npc?.StopMoving();
        }
        if (interacting && string.Equals(user.Username, interactingWith, System.StringComparison.OrdinalIgnoreCase))
        {
            npc?.StopListening(user.Username);
            EndInteraction();
        }
    }

    public override void OnDestroy()
    {
        npc?.Destroy();
    }
}