using UnityEditor;
using UnityEngine;

namespace MantisLODEditor
{
    [CustomEditor(typeof(ProgressiveMeshRuntime))]
  public class ProgressiveMeshRuntimeEditor : Editor {
    private ProgressiveMesh save_progressiveMesh = null;
    private bool show_advanced_options = true;

    override public void OnInspectorGUI() {
      DrawDefaultInspector();
      var runtime = target as ProgressiveMeshRuntime;
      if(runtime) {
        // when the property changed
        if (runtime.progressiveMesh != save_progressiveMesh) {
          // clear the property
          if (runtime.progressiveMesh == null) {
            runtime.reset_all_parameters();
          } else {
            // diffent property or mesh lod range not exists
            if (save_progressiveMesh != null || runtime.mesh_lod_range == null || runtime.mesh_lod_range.Length == 0) {
              runtime.reset_all_parameters();
              int max_lod_count = runtime.progressiveMesh.triangles[0];
              int mesh_count = runtime.progressiveMesh.triangles[1];
              runtime.mesh_lod_range = new int[mesh_count*2];
              for (int i=0; i<mesh_count; i++) {
                runtime.mesh_lod_range[i*2] = 0;
                runtime.mesh_lod_range[i*2+1] = max_lod_count-1;
              }
            }
          }
          save_progressiveMesh = runtime.progressiveMesh;
        }
        // show advanced options
        show_advanced_options = EditorGUILayout.Foldout(show_advanced_options, show_advanced_options?"Hide Advanced Options":"Show Advanced Options");
        if (show_advanced_options) {
          GUIStyle helpStyle = new GUIStyle(GUI.skin.box);
          helpStyle.wordWrap = true;
          helpStyle.alignment = TextAnchor.UpperLeft;
          GUILayout.Label(
            "If the gameObject is an instance of a prefab, you must drag the gameObject from the hierarchy window onto the source prefab to save the changes when finished editing. Otherwise, all the changes will lose after reloading the scene!"
            , helpStyle
            , GUILayout.ExpandWidth(true));
          runtime.updateInterval = EditorGUILayout.FloatField("Update Interval", runtime.updateInterval);
          GUILayout.Label(
            "How often to check LOD changes."
            , helpStyle
            , GUILayout.ExpandWidth(true));
          // clamp to valid range
          if (runtime.updateInterval < 0.1f) runtime.updateInterval = 0.1f;
          if (runtime.updateInterval > 5.0f) runtime.updateInterval = 5.0f;
          EditorGUILayout.Space();
          runtime.never_cull = EditorGUILayout.Toggle ("Never Cull", runtime.never_cull);
          GUILayout.Label(
            "The gameObject is alway visible or be culled when far away."
            , helpStyle
            , GUILayout.ExpandWidth(true));
          runtime.cull_ratio = EditorGUILayout.FloatField("Cull Ratio", runtime.cull_ratio);
          if (!runtime.never_cull) {
            GUILayout.Label(
              "How far away will the gameObject be culled."
              , helpStyle
              , GUILayout.ExpandWidth(true));
          }
          // clamp to valid range
          if (runtime.cull_ratio < 0.0f) runtime.cull_ratio = 0.0f;
          if (runtime.cull_ratio > 1.0f) runtime.cull_ratio = 1.0f;
          string[] options = new string[] { "Cull By Size", "Cull By Distance" };
          runtime.lod_strategy = GUILayout.SelectionGrid(runtime.lod_strategy, options, 1, EditorStyles.radioButton);
          if (runtime.lod_strategy == 1) {
            runtime.disappear_distance = EditorGUILayout.FloatField("Disappear Distance", runtime.disappear_distance);
            GUILayout.Label(
              "How far away will the gameObject look like a tiny point."
              , helpStyle
              , GUILayout.ExpandWidth(true));
            // clamp to valid range
            if (runtime.disappear_distance < 0.0f) runtime.disappear_distance = 0.0f;
          }
          // mesh lod range exists
          if (runtime.mesh_lod_range != null && runtime.mesh_lod_range.Length != 0) {
            for (int i=0; i<runtime.mesh_lod_range.Length; i++) {
              if (i % 2 == 0) {
                EditorGUILayout.Space();
                // mesh name
                EditorGUILayout.LabelField("Mesh: " + runtime.progressiveMesh.uuids[i/2]);
                // min lod
                runtime.mesh_lod_range[i] = EditorGUILayout.IntField("Min LOD", runtime.mesh_lod_range[i]);
                EditorGUILayout.LabelField("Triangles Count: " + runtime.get_triangles_count_from_progressive_mesh(runtime.mesh_lod_range[i], i/2).ToString());
                GUILayout.Label(
                  "Adjust to avoid too much detailed."
                  , helpStyle
                  , GUILayout.ExpandWidth(true));
              } else {
                // max lod
                runtime.mesh_lod_range[i] = EditorGUILayout.IntField("Max LOD", runtime.mesh_lod_range[i]);
                EditorGUILayout.LabelField("Triangles Count: " + runtime.get_triangles_count_from_progressive_mesh(runtime.mesh_lod_range[i], i/2).ToString());
                GUILayout.Label(
                  "Adjust to avoid too much simplified."
                  , helpStyle
                  , GUILayout.ExpandWidth(true));
              }
              // clamp to valid range
              int max_lod_count = runtime.progressiveMesh.triangles[0];
              if (runtime.mesh_lod_range[i] < 0) runtime.mesh_lod_range[i] = 0;
              if (runtime.mesh_lod_range[i] > max_lod_count-1) runtime.mesh_lod_range[i] = max_lod_count-1;
            }
          }
        }
      }
    }
  }
}