﻿/*
MIT License

Copyright(c) 2019 Mitchel Thompson
www.angryarugula.com

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
*/

using System.Collections;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;
#if UNITY_EDITOR
using UnityEditor;
#endif

namespace Arugula.Widgets
{
    public class Protractor : MonoBehaviour
    {
        [System.Serializable]
        public class Mark
        {
            public string name;
            [Range(-180f, 180f)]
            public float value;
        }

        [Range(1, 90)]
        public int denomination = 5;
        [Range(1, 90)]
        public int labeledDenominiation = 10;

        public float radius = 1;
        public float angle = 180;
        public Transform target;
        public float targetAngle = 0;

        public List<Mark> marks = new List<Mark>();
        public bool drawLineToTarget;
        public bool alwaysDraw = true;

        public float CurrentAngle
        {
            get
            {
                if (target == null)
                    return targetAngle;

                Plane p = new Plane(transform.up, transform.position);
                Ray ray = new Ray(target.position, p.GetSide(target.position) ? -transform.up : transform.up);
                float dist = 0;
                if (p.Raycast(ray, out dist))
                {
                    Vector3 pos = ray.GetPoint(dist);
                    return Vector3.SignedAngle(transform.forward, pos - transform.position, transform.up);
                }
                else
                {
                    return Vector3.SignedAngle(transform.forward, target.position - transform.position, transform.up);
                }
            }
        }

        public float this[string name]
        {
            get
            {
                Mark mark = marks.FirstOrDefault(x => x.name == name);
                if (mark != null)
                    return mark.value;

                return 0;
            }
        }

        private void OnDrawGizmos()
        {
            if (alwaysDraw)
                Draw();
        }

        private void OnDrawGizmosSelected()
        {
            if (!alwaysDraw)
                Draw();
        }

        void Draw()
        {
#if UNITY_EDITOR
            Handles.DrawWireArc(transform.position, transform.up, transform.rotation * Quaternion.Euler(0, -angle / 2, 0) * Vector3.forward, angle, radius);

            for (int i = -180; i < 180; i++)
            {
                if (i < angle / -2 || i > angle / 2)
                    continue;

                if (i % denomination != 0 && i % labeledDenominiation != 0)
                    continue;

                float len = 0.8f;

                bool majorDenomination = false;
                if (i % labeledDenominiation != 0)
                {
                    len = 0.9f;
                }
                else
                {
                    majorDenomination = true;
                }

                Vector3 innerPoint = GetArcPoint(i, radius * len);

                Handles.color = Color.white;
                if (majorDenomination)
                    Handles.Label(innerPoint, i.ToString());


                Handles.DrawLine(GetArcPoint(i, radius), innerPoint);
            }

            Handles.color = Color.red;
            foreach (var m in marks)
            {
                Vector3 end = GetArcPoint(m.value, radius * 1.1f);
                Handles.DrawLine(GetArcPoint(m.value, radius * 0.9f), end);
                Handles.Label(end, m.name);
            }

            if (target != null)
            {
                Plane p = new Plane(transform.up, transform.position);
                Ray ray = new Ray(target.position, p.GetSide(target.position) ? -transform.up : transform.up);
                float dist = 0;
                if (p.Raycast(ray, out dist))
                {
                    Vector3 pos = ray.GetPoint(dist);
                    float angle = Vector3.SignedAngle(transform.forward, pos - transform.position, transform.up);
                    Handles.color = Color.green;
                    float len = drawLineToTarget ? Vector3.Distance(transform.position, pos) : radius * 1.25f;
                    Vector3 endPoint = GetArcPoint(angle, len);
                    Handles.DrawLine(transform.position, endPoint);
                    if (drawLineToTarget)
                        Handles.DrawLine(endPoint, target.position);

                    Handles.Label(GetArcPoint(angle, radius * 1.25f), $"{angle.ToString("f1")}°");
                }
                else
                {
                    float angle = Vector3.SignedAngle(transform.forward, target.position - transform.position, transform.up);
                    Handles.color = Color.green;
                    float len = drawLineToTarget ? Vector3.Distance(transform.position, target.position) : radius * 1.25f;
                    Handles.DrawLine(transform.position, GetArcPoint(angle, len));


                    Handles.Label(GetArcPoint(angle, radius * 1.25f), $"{angle.ToString("f1")}°");
                }

                if (drawLineToTarget)
                    Handles.DrawDottedLine(transform.position, target.position, 5f);
            }
            else
            {
                Handles.color = Color.green;
                Handles.DrawLine(transform.position, GetArcPoint(targetAngle, radius * 1.25f));
                Handles.Label(GetArcPoint(targetAngle, radius * 1.25f), $"{targetAngle.ToString("f1")}°");
            }
#endif

        }

        Vector3 GetArcPoint(float angle, float distance)
        {
            return transform.position + transform.rotation * Quaternion.Euler(0, angle, 0) * Vector3.forward * distance;
        }


    }
}