using UdonSharp;
using UnityEngine;
using VRC.SDK3.Components;
using VRC.SDKBase;

[UdonBehaviourSyncMode(BehaviourSyncMode.NoVariableSync)]
[DisallowMultipleComponent]
[AddComponentMenu("Artyom Scripting System/Jump Pad Controller")]
public class JumpPad : UdonSharpBehaviour
{
    public bool debug;
    public Animator launchAnim;
    public string animName = "isLaunch";
    public Transform jumpTarget;
    public Transform self;
    public float arcTime = 1.2f;
    public float walkLimit = 0.2f;
    public float runLimit = 0.4f;
    public float strafeLimit = 0.2f;
    private Vector3 appliedVelocity;

    private float defaultWalk;
    private float defaultStrafe;
    private float defaultRun;

    private VRCPlayerApi player;
    private bool ready;
    private int localLaunches; // Launches of the local player still in the air
    private int animLaunches; // Launches of anyone still holding the launch animation on

    void Start()
    {
        // The inspector's Animator wins; only fall back to one on this object
        if (launchAnim == null) launchAnim = GetComponent<Animator>();
        if (self == null) self = transform;
        if (jumpTarget == null)
        {
            Debug.LogError("[AUMSS] Jump Pad Controller: Jump Target isn't assigned, so the pad won't launch anything.");
            return;
        }
        ready = true;
        if (debug) Debug.Log("Jump Pad Controller: Velocity Calculated to:" + CalculateInitialVelocity(self.position, jumpTarget.position, Physics.gravity.y, arcTime).ToString());
    }

    public static Vector3 CalculateInitialVelocity(Vector3 origin, Vector3 target, float gravity, float time)
    {
        // Compute the differences in position
        Vector3 displacement = target - origin;

        // Calculate the initial velocity components
        Vector3 initialVelocity = new Vector3(
            displacement.x / time,                              // Horizontal X velocity
            (displacement.y - 0.5f * gravity * time * time) / time, // Vertical Y velocity
            displacement.z / time                               // Horizontal Z velocity
        );

        return initialVelocity;
    }

    private float LaunchDuration()
    {
        return Mathf.Max(arcTime - 0.2f, 0f);
    }

    public override void OnPlayerTriggerEnter(VRCPlayerApi collidedPlayer)
    {
        if (!ready) return;
        StartLaunchAnim();
        SendCustomEventDelayedSeconds(nameof(EndLaunchAnim), LaunchDuration());
        // Remote players get launched by their own client, and speed/velocity calls on them throw and halt this script
        if (!collidedPlayer.isLocal) return;

        player = collidedPlayer;
        // Only save the speeds when not already mid-launch: mid-launch they're the limits, and would be kept forever
        if (localLaunches == 0)
        {
            defaultRun = player.GetRunSpeed();
            defaultStrafe = player.GetStrafeSpeed();
            defaultWalk = player.GetWalkSpeed();
        }
        localLaunches++;

        // Players fall with the world's gravity scaled by their own gravity strength
        appliedVelocity = CalculateInitialVelocity(self.position, jumpTarget.position, Physics.gravity.y * player.GetGravityStrength(), arcTime);
        LimitMobility();
        player.SetVelocity(appliedVelocity);

        if (debug) Debug.Log("Jump Pad Controller: Player Velocity Set to:" + appliedVelocity.ToString());
        SendCustomEventDelayedSeconds(nameof(Mobilize), LaunchDuration());
    }

    private void OnTriggerEnter(Collider other)
    {
        if (!ready || other == null) return;
        VRC_Pickup pickup = other.GetComponent<VRC_Pickup>();
        Rigidbody body = other.GetComponent<Rigidbody>();
        if (pickup == null || body == null) return;
        // A synced pickup is launched by its owner; anyone else setting its velocity just fights the sync
        if (other.GetComponent<VRCObjectSync>() != null && !Networking.IsOwner(other.gameObject)) return;

        appliedVelocity = CalculateInitialVelocity(self.position, jumpTarget.position, Physics.gravity.y, arcTime);
        pickup.Drop();
        body.velocity = appliedVelocity;
    }

    public void LimitMobility()
    {
        if (!Utilities.IsValid(player)) return;
        player.SetWalkSpeed(walkLimit);
        player.SetRunSpeed(runLimit);
        player.SetStrafeSpeed(strafeLimit);
        if (debug) Debug.Log("Jump Pad Controller: Limited Player Mobility for " + arcTime.ToString() + " seconds");
    }

    public void Mobilize()
    {
        if (localLaunches > 0) localLaunches--;
        if (localLaunches > 0 || !Utilities.IsValid(player)) return; // Still in the air from a later launch
        player.SetWalkSpeed(defaultWalk);
        player.SetRunSpeed(defaultRun);
        player.SetStrafeSpeed(defaultStrafe);
        if (debug) Debug.Log("Jump Pad Controller: De-Limited Player Mobility after" + arcTime.ToString() + " seconds");
    }

    private void StartLaunchAnim()
    {
        animLaunches++;
        if (launchAnim == null || string.IsNullOrEmpty(animName)) return;
        launchAnim.SetBool(animName, true);
        if (debug) Debug.Log("Jump Pad Controller: Animator State attempted to be set to True");
    }

    public void EndLaunchAnim()
    {
        if (animLaunches > 0) animLaunches--;
        if (animLaunches > 0) return; // Someone else launched since; their launch ends it
        if (launchAnim == null || string.IsNullOrEmpty(animName)) return;
        launchAnim.SetBool(animName, false);
        if (debug) Debug.Log("Jump Pad Controller: Animator State attempted to be set to False");
    }
}