using UnityEditor;
using UnityEngine;
using System;
using System.Linq;

namespace NanoBrain.Unity {

    public class ClusterPickerWindow : EditorWindow {
        private Vector2 scroll;
        private ClusterPrefab[] items = new ClusterPrefab[0];
        private Action<ClusterPrefab> onPicked;
        private string search = "";

        public static void ShowPicker(Action<ClusterPrefab> onPicked, string title = "Select Cluster") {
            var w = CreateInstance<ClusterPickerWindow>();
            w.titleContent = new GUIContent(title);
            w.minSize = new Vector2(360, 320);
            w.onPicked = onPicked;
            w.RefreshList();
            w.ShowModalUtility(); // modal dialog
        }

        private void OnEnable() => RefreshList();

        private void RefreshList() {
            var guids = AssetDatabase.FindAssets("t:ClusterPrefab");
            items = guids
                .Select(g => AssetDatabase.LoadAssetAtPath<ClusterPrefab>(AssetDatabase.GUIDToAssetPath(g)))
                .Where(b => b != null)
                .OrderBy(b => b.name)
                .ToArray();
        }

        private void OnGUI() {
            EditorGUILayout.Space();
            EditorGUILayout.BeginHorizontal();
            EditorGUILayout.LabelField("Choose Cluster:", EditorStyles.boldLabel);
            if (GUILayout.Button("Refresh", GUILayout.Width(80))) RefreshList();
            GUILayout.FlexibleSpace();
            EditorGUILayout.EndHorizontal();

            EditorGUILayout.Space();
            search = EditorGUILayout.TextField(search);

            EditorGUILayout.Space();
            scroll = EditorGUILayout.BeginScrollView(scroll);
            foreach (var it in items) {
                if (!string.IsNullOrEmpty(search) && it.name.IndexOf(search, StringComparison.OrdinalIgnoreCase) < 0)
                    continue;

                EditorGUILayout.BeginHorizontal();
                EditorGUILayout.LabelField(EditorGUIUtility.ObjectContent(it, typeof(ClusterPrefab)), GUILayout.Height(20));
                if (GUILayout.Button("Select", GUILayout.Width(70))) {
                    onPicked?.Invoke(it);
                    Close();
                    return;
                }
                EditorGUILayout.EndHorizontal();
            }
            EditorGUILayout.EndScrollView();

            EditorGUILayout.Space();
            EditorGUILayout.BeginHorizontal();
            if (GUILayout.Button("Cancel")) { onPicked?.Invoke(null); Close(); }
            GUILayout.FlexibleSpace();
            EditorGUILayout.EndHorizontal();
        }
    }

}