/******************************************************************************/
/*
  Project   - MudBun
  Publisher - Long Bunny Labs
              http://LongBunnyLabs.com
  Author    - Ming-Lun "Allen" Chou
              http://AllenChou.net
*/
/******************************************************************************/

#if UNITY_EDITOR

using System;
using UnityEngine;
using UnityEditor;

namespace MudBun
{
  [CustomPropertyDrawer(typeof(ConditionalFieldAttribute))]
  public class ConditionalFieldAttributeDrawer : PropertyDrawer
  {
    public static string AsStringValue(SerializedProperty property)
    {
      switch (property.propertyType)
      {
        case SerializedPropertyType.String:
          return property.stringValue;

        case SerializedPropertyType.Character:
        case SerializedPropertyType.Integer:
          if (property.type == "char") return System.Convert.ToChar(property.intValue).ToString();
          return property.intValue.ToString();

        case SerializedPropertyType.ObjectReference:
          return property.objectReferenceValue != null ? property.objectReferenceValue.ToString() : "null";

        case SerializedPropertyType.Boolean:
          return property.boolValue.ToString();

        case SerializedPropertyType.Enum:
          return property.enumNames[property.enumValueIndex];

        default:
          return string.Empty;
      }
    }

    private ConditionalFieldAttribute Attribute
    {
      get
      {
        return _attribute ?? (_attribute = attribute as ConditionalFieldAttribute);
      }
    }

    private string PropertyToCheck { get => Attribute != null ? _attribute.PropertyToCheck : null; }
    private object CompareValue  { get => Attribute != null ? _attribute.CompareValue  : null; }
    private object CompareValue2 { get => Attribute != null ? _attribute.CompareValue2 : null; }
    private object CompareValue3 { get => Attribute != null ? _attribute.CompareValue3 : null; }
    private object CompareValue4 { get => Attribute != null ? _attribute.CompareValue4 : null; }
    private object CompareValue5 { get => Attribute != null ? _attribute.CompareValue5 : null; }
    private object CompareValue6 { get => Attribute != null ? _attribute.CompareValue6 : null; }

    private ConditionalFieldAttribute _attribute;

    private bool ShouldShow(SerializedProperty property)
    {
      if (PropertyToCheck != null && !PropertyToCheck.Equals(""))
      {
        var conditionProperty = FindPropertyRelative(property, PropertyToCheck);
        if (conditionProperty != null)
        {

          var aCompVal = new object[]
          {
            CompareValue,
            CompareValue2,
            CompareValue3,
            CompareValue4,
            CompareValue5,
            CompareValue6,
          };

          bool matched = false;
          foreach (object compVal in aCompVal)
          {
            if (compVal == null)
              continue;

            bool isBoolMatch = conditionProperty.propertyType == SerializedPropertyType.Boolean && conditionProperty.boolValue;
            string compareStringValue = compVal != null ? compVal.ToString().ToUpper() : "NULL";
            if (isBoolMatch && compareStringValue == "FALSE") isBoolMatch = false;

            string conditionPropertyStringValue = AsStringValue(conditionProperty).ToUpper();
            bool objectMatch = compareStringValue == conditionPropertyStringValue;

            if (!isBoolMatch && !objectMatch)
              continue;

            matched = true;
            break;
          }

          if (!matched)
          {
            return false;
          }
        }
      }

      return true;
    }

    public override float GetPropertyHeight(SerializedProperty property, GUIContent label)
    {
      return 
        ShouldShow(property) 
          ? EditorGUI.GetPropertyHeight(property) 
          : 0.0f;
    }

    // TODO: Skip array fields
    public override void OnGUI(Rect position, SerializedProperty property, GUIContent content)
    {
      if (!ShouldShow(property))
        return;

      if (!Attribute.Label.Equals(""))
        content.text = Attribute.Label;

      if (!Attribute.Tooltip.Equals(""))
        content.tooltip = Attribute.Tooltip;

      if (Attribute.ShowRange)
      {
        if (property.propertyType == SerializedPropertyType.Float)
          EditorGUI.Slider(position, property, Attribute.Min, Attribute.Max, content);
        else if (property.propertyType == SerializedPropertyType.Integer)
          EditorGUI.IntSlider(position, property, Convert.ToInt32(Attribute.Min), Convert.ToInt32(Attribute.Max), content);
        else
          EditorGUI.LabelField(position, content.text, "Use Range with float or int.");
      }
      else
      {
        EditorGUI.PropertyField(position, property, content);
      }
    }

    private SerializedProperty FindPropertyRelative(SerializedProperty property, string toGet)
    {
      if (property.depth == 0) return property.serializedObject.FindProperty(toGet);

      var path = property.propertyPath.Replace(".Array.data[", "[");
      var elements = path.Split('.');
      SerializedProperty parent = null;

      for (int i = 0; i < elements.Length - 1; i++)
      {
        var element = elements[i];
        int index = -1;
        if (element.Contains("["))
        {
          index = Convert.ToInt32(element.Substring(element.IndexOf("[", StringComparison.Ordinal)).Replace("[", "").Replace("]", ""));
          element = element.Substring(0, element.IndexOf("[", StringComparison.Ordinal));
        }

        parent = i == 0 ?
          property.serializedObject.FindProperty(element) :
          parent.FindPropertyRelative(element);

        if (index >= 0) parent = parent.GetArrayElementAtIndex(index);
      }

      return parent.FindPropertyRelative(toGet);
    }
  }
}
#endif