// CharacterPhysicsModes.cs
// Ragdoll physics for players: the Drop button (or a fall trigger) turns the player's body into a ragdoll that falls
// onto the ground, terrain, furniture or moving physics objects; the Stand button (or the recover timers) gets them up
// again. The Ragdoll settings below are sent to each player before they fall.
using System.Collections;
using System.Collections.Generic;
using IHXR.Simulation;

public class CharacterPhysicsModes : ScriptBase
{
    public SceneObject DropButton;
    public SceneObject StandButton;
    public SceneObject FallStartTrigger;
    public SceneObject FallStopTrigger;
    public SceneObject FallStartAudioObject;
    public SceneObject FallStopAudioObject;
    public SceneObject DropAudioObject;

    public float dropRecoverSeconds = 3.0f;
    public float fallRecoverSeconds = 0.0f;
    public float fallStopRecoverSeconds = 0.0f;
    public float standTransitionSeconds = 0.8f;
    public bool resetUsersOnJoin = true;
    public bool highlightButtons = true;
    public float interactDistance = 10f;
    public int audioSourceIndex = 0;
    public bool includeAudioChildren = true;
    public bool stopAudioBeforePlay = true;

    [Header("Ragdoll")]
    [Tooltip("Muscles: 0 = completely limp, 1 = stiff as a statue. Around 0.1 to 0.2 looks like a person falling.")]
    [Range(0f, 1f)]
    public float ragdollStrength = 0.12f;
    [Tooltip("1 = normal gravity, 0.5 = floaty, 2 = heavy.")]
    [Range(-2f, 3f)]
    public float ragdollGravityScale = 1f;
    [Tooltip("Air drag: 0 = none, higher = the body slows down sooner.")]
    [Range(0f, 0.5f)]
    public float ragdollDamping = 0.02f;
    [Tooltip("0 = the body slides along surfaces, 1 = it stops where it lands.")]
    [Range(0f, 1f)]
    public float ragdollFriction = 0.6f;
    [Tooltip("0 = no bounce, 1 = bounces right back.")]
    [Range(0f, 1f)]
    public float ragdollBounciness = 0.08f;
    [Tooltip("How hard the Drop button pushes the player (in the direction below) as they fall. 0 = they just collapse.")]
    public float dropPushPower = 0f;
    public Vector3 dropPushDirection = new Vector3(0f, 0.3f, 1f);

    Dictionary<string, int> activeFallTokens = new Dictionary<string, int>();
    Dictionary<string, int> landedFallTokens = new Dictionary<string, int>();
    int nextFallToken;

    public override void Start()
    {
        RegisterButtons();
        RegisterFallTriggers();
    }

    public override void OnUserJoin(UserInfo user)
    {
        string username = user != null ? user.Username : null;

        if (resetUsersOnJoin && !string.IsNullOrWhiteSpace(username))
        {
            ClearFallState(username);
            StopCharacterPhysicsMode(username, standTransitionSeconds);
        }

        RegisterButtons(username);
    }

    void RegisterButtons(string targetUsername = null)
    {
        if (DropButton != null && !DropButton.IsNull)
        {
            MakeInteractable(
                DropButton,
                OnDropClicked,
                highlightButtons,
                targetUsername,
                true,
                interactDistance,
                "Drop");
        }

        if (StandButton != null && !StandButton.IsNull)
        {
            MakeInteractable(
                StandButton,
                OnStandClicked,
                highlightButtons,
                targetUsername,
                true,
                interactDistance,
                "Stand");
        }
    }

    void RegisterFallTriggers()
    {
        if (FallStartTrigger != null && !FallStartTrigger.IsNull)
            RegisterTrigger(FallStartTrigger, OnFallStartEnter);

        if (FallStopTrigger != null && !FallStopTrigger.IsNull)
            RegisterTrigger(FallStopTrigger, OnFallStopEnter);
    }

    void OnDropClicked(InteractionInfo info)
    {
        if (info == null || string.IsNullOrWhiteSpace(info.Username))
            return;

        SendRagdollSettings(info.Username);
        ApplyCharacterImpact(
            info.Username,
            dropPushPower > 0f ? dropPushDirection : Vector3.zero,
            dropPushPower,
            0.15f,
            true,
            dropRecoverSeconds,
            CharacterImpactPart.All);

        PlayOptionalAudio(DropAudioObject);
    }

    void OnStandClicked(InteractionInfo info)
    {
        if (info == null || string.IsNullOrWhiteSpace(info.Username))
            return;

        ClearFallState(info.Username);
        StopCharacterPhysicsMode(info.Username, standTransitionSeconds);
    }

    void OnFallStartEnter(TriggerInfo info)
    {
        if (info == null || !info.IsPlayer || string.IsNullOrWhiteSpace(info.Username))
            return;

        string username = info.Username.Trim();
        int token = StartNewFallCycle(username);

        StopCharacterPhysicsMode(username, 0f);
        PlayOptionalAudio(FallStartAudioObject);
        StartCoroutine(SetFallingNextFrame(username, token));
    }

    IEnumerator SetFallingNextFrame(string username, int token)
    {
        yield return null;

        if (!IsActiveFall(username, token))
            yield break;

        SendRagdollSettings(username);
        SetCharacterPhysicsMode(
            username,
            CharacterPhysicsMode.Falling,
            0.15f,
            0f);

        ScheduleFallAutoRecover(username, token);
    }

    void OnFallStopEnter(TriggerInfo info)
    {
        if (info == null || !info.IsPlayer || string.IsNullOrWhiteSpace(info.Username))
            return;

        string username = info.Username.Trim();
        int token;
        if (!activeFallTokens.TryGetValue(username, out token))
            return;

        int landedToken;
        if (landedFallTokens.TryGetValue(username, out landedToken) && landedToken == token)
            return;

        landedFallTokens[username] = token;
        PlayOptionalAudio(FallStopAudioObject);
        ScheduleFallStop(username, token);
    }

    int StartNewFallCycle(string username)
    {
        nextFallToken++;
        if (nextFallToken == int.MaxValue)
            nextFallToken = 1;

        activeFallTokens[username] = nextFallToken;
        landedFallTokens.Remove(username);
        return nextFallToken;
    }

    bool IsActiveFall(string username, int token)
    {
        int activeToken;
        return activeFallTokens.TryGetValue(username, out activeToken) && activeToken == token;
    }

    void ScheduleFallAutoRecover(string username, int token)
    {
        float delaySeconds = Mathf.Max(0f, fallRecoverSeconds);
        if (delaySeconds > 0f)
            StartCoroutine(AutoRecoverFallAfterDelay(username, token, delaySeconds));
    }

    IEnumerator AutoRecoverFallAfterDelay(string username, int token, float delaySeconds)
    {
        yield return new WaitForSeconds(delaySeconds);

        int landedToken;
        if (IsActiveFall(username, token) && !landedFallTokens.TryGetValue(username, out landedToken))
            CompleteFallCycle(username, token);
    }

    void ScheduleFallStop(string username, int token)
    {
        float delaySeconds = GetFallStopRecoverSeconds();
        if (delaySeconds <= 0f)
        {
            CompleteFallCycle(username, token);
            return;
        }

        StartCoroutine(StopFallingAfterDelay(username, token, delaySeconds));
    }

    float GetFallStopRecoverSeconds()
    {
        if (fallStopRecoverSeconds > 0f)
            return fallStopRecoverSeconds;

        return Mathf.Max(0f, fallRecoverSeconds);
    }

    IEnumerator StopFallingAfterDelay(string username, int token, float delaySeconds)
    {
        yield return new WaitForSeconds(delaySeconds);

        CompleteFallCycle(username, token);
    }

    void CompleteFallCycle(string username, int token)
    {
        if (!IsActiveFall(username, token))
            return;

        activeFallTokens.Remove(username);
        landedFallTokens.Remove(username);
        StopCharacterPhysicsMode(username, standTransitionSeconds);
    }

    void ClearFallState(string username)
    {
        activeFallTokens.Remove(username);
        landedFallTokens.Remove(username);
    }

    void SendRagdollSettings(string username)
    {
        CharacterRagdollSettings settings = new CharacterRagdollSettings();
        settings.Strength = ragdollStrength;
        settings.GravityScale = ragdollGravityScale;
        settings.Damping = ragdollDamping;
        settings.Friction = ragdollFriction;
        settings.Bounciness = ragdollBounciness;
        SetCharacterRagdollSettings(username, settings);
    }

    void PlayOptionalAudio(SceneObject audioObject)
    {
        if (audioObject == null || audioObject.IsNull)
            return;

        if (stopAudioBeforePlay)
            StopAudio(audioObject, null, audioSourceIndex, includeAudioChildren);

        PlayAudio(audioObject, null, audioSourceIndex, includeAudioChildren);
    }
}