using UnityEngine;
using System;
using System.Collections.Generic;

namespace UnityEditor.Experimental.VFX.Toolbox
{
    internal class VFXToolboxGUIUtility
    {
        #region GUIContent caching
        private static Dictionary<string, GUIContent> s_GUIContentCache;

        public static GUIContent Get(string textAndTooltip)
        {
            return GetTextAndIcon(textAndTooltip, null);
        }

        public static GUIContent GetTextAndIcon(string textAndTooltip, string icon)
        {
            if (s_GUIContentCache == null)
                s_GUIContentCache = new Dictionary<string, GUIContent>();

            if (string.IsNullOrEmpty(textAndTooltip))
                return GUIContent.none;

            GUIContent content;

            if (!s_GUIContentCache.TryGetValue(textAndTooltip, out content))
            {
                var s = textAndTooltip.Split('|');

                if (!string.IsNullOrEmpty(icon))
                {
                    var iconContent = EditorGUIUtility.IconContent(icon);
                    content = new GUIContent(s[0], iconContent.image);
                }
                else
                {
                    content = new GUIContent(s[0]);
                }

                if (s.Length > 1 && !string.IsNullOrEmpty(s[1]))
                    content.tooltip = s[1];

                s_GUIContentCache.Add(textAndTooltip, content);
            }

            return content;

        }

        public static void Clear()
        {
            s_GUIContentCache.Clear();
        }
        #endregion

        #region ProgressBar Handling

        private static double s_LastProgressBarTime;

        /// <summary>
        /// Displays a progress bar with delay and optional cancel button
        /// </summary>
        /// <param name="title">title of the window</param>
        /// <param name="message">message</param>
        /// <param name="progress">progress</param>
        /// <param name="delay">minimum delay before displaying window</param>
        /// <param name="cancelable">is the window cancellable?</param>
        /// <returns>true if cancelled, false otherwise</returns>
        public static bool DisplayProgressBar(string title, string message, float progress, float delay = 0.0f, bool cancelable = false)
        {
            if(s_LastProgressBarTime < 0.0)
                s_LastProgressBarTime = EditorApplication.timeSinceStartup;

            if (EditorApplication.timeSinceStartup - s_LastProgressBarTime > delay)
            {
                if(cancelable)
                {
                    return EditorUtility.DisplayCancelableProgressBar(title, message, progress);
                }
                else
                {
                    EditorUtility.DisplayProgressBar(title, message, progress);
                    return false;
                }
            }
            return false;
        }

        /// <summary>
        /// Clears the current progressbar
        /// </summary>
        public static void ClearProgressBar()
        {
            s_LastProgressBarTime = -1.0;
            EditorUtility.ClearProgressBar();
        }

        #endregion

        #region Other GUI Utils
        public static void GUIRotatedLabel(Rect position, string label, float angle, GUIStyle style)
        {
            var matrix = GUI.matrix;
            var rect = new Rect(position.x - 10f, position.y, position.width, position.height);
            GUIUtility.RotateAroundPivot(angle, rect.center);
            GUI.Label(rect, label, style);
            GUI.matrix = matrix;
        }
        #endregion

        #region ToggleableHeader

        public static bool ToggleableHeader(bool enabled, bool bToggleable, string title)
        {
            Rect rect = GUILayoutUtility.GetRect(16f, 32f, VFXToolboxStyles.Header);
            using (new EditorGUI.DisabledGroupScope(!enabled))
            {
                GUI.Box(rect, title, VFXToolboxStyles.Header);
            }
            if(bToggleable)
            {
                Rect toggleRect = new Rect(rect.x + 10f, rect.y + 6f, 13f, 13f);
                if (Event.current.type == EventType.Repaint)
                    VFXToolboxStyles.HeaderCheckBox.Draw(toggleRect, false, false, enabled, false);

                Event e = Event.current;
                if (e.type == EventType.MouseDown)
                {
                    if (toggleRect.Contains(e.mousePosition))
                    {
                        enabled = !enabled;
                        e.Use();
                    }
                }
            }

            return enabled;
        }

        #endregion

        #region Tabbed Buttons
        public static int TabbedButtonsGUILayout(int value, string[] labels, bool[] enabled)
        {
            int count = labels.Length;

            int selected = value;

            if (labels.Length != enabled.Length)
                throw new ArgumentException("Labels or enabled arrays does not match count for EnumTabbedButtons()");

            int i = 0;

            using (new EditorGUILayout.HorizontalScope())
            {
                foreach(string label in labels)
                {
                    GUIStyle style = (i == 0) ? VFXToolboxStyles.TabButtonLeft : ((i == count - 1) ? VFXToolboxStyles.TabButtonRight : VFXToolboxStyles.TabButtonMid);
                    using (new EditorGUI.DisabledScope(!enabled[i]))
                    {
                        bool val = GUILayout.Toggle(selected == i, Get(label), style, GUILayout.Height(24));
                        if(val != (selected == i))
                        {
                            selected = i;
                        }
                    }
                    i++; 
                }
            }
            return selected;
        }
        #endregion

        #region Custom Scopes

        public class HeaderSectionScope : GUI.Scope
        {
            public HeaderSectionScope(string headerText)
            {
                EditorGUILayout.LabelField(Get(headerText), s_Styles.header);
                EditorGUI.indentLevel += 1;
            }

            protected override void CloseScope()
            {
                EditorGUI.indentLevel -= 1;
                GUILayout.Label(GUIContent.none, s_Styles.separator);
            }

            static Styles s_Styles = new Styles();

            private class Styles
            {
                public GUIStyle header;
                public GUIStyle separator;

                public Styles()
                {
                    header = new GUIStyle(EditorStyles.boldLabel);
                    header.margin = new RectOffset(0, 0, 0, 12);
                    separator = new GUIStyle("sv_iconselector_sep");
                    separator.margin = new RectOffset(0, 0, 8, 0);
                }
            }
        }
        #endregion

    }
}