//********************************** Banshee Engine (www.banshee3d.com) **************************************************//
//**************** Copyright (c) 2016 Marko Pintera (marko.pintera@gmail.com). All rights reserved. **********************//

using bs;

namespace bs.Editor
{
    /** @addtogroup Inspector
     *  @{
     */

    /// <summary>
    /// Displays GUI for a serializable property containing an integer value.
    /// </summary>
    public class InspectableInt : InspectableField
    {
        private GUIIntField guiIntField;
        private InspectableState state;
        private InspectableFieldStyleInfo style;

        /// <summary>
        /// Creates a new inspectable integer GUI for the specified property.
        /// </summary>
        /// <param name="context">Context shared by all inspectable fields created by the same parent.</param>
        /// <param name="title">Name of the property, or some other value to set as the title.</param>
        /// <param name="path">Full path to this property (includes name of this property and all parent properties).</param>
        /// <param name="depth">Determines how deep within the inspector nesting hierarchy is this field. Some fields may
        ///                     contain other fields, in which case you should increase this value by one.</param>
        /// <param name="layout">Parent layout that all the field elements will be added to.</param>
        /// <param name="property">Serializable property referencing the field whose contents to display.</param>
        /// <param name="style">Information that can be used for customizing field rendering and behaviour.</param>
        public InspectableInt(InspectableContext context, string title, string path, int depth, InspectableFieldLayout layout, 
            SerializableProperty property, InspectableFieldStyleInfo style)
            : base(context, title, path, SerializableProperty.FieldType.Int, depth, layout, property)
        {
            this.style = style;
        }

        /// <inheritdoc/>
        protected internal override void Initialize(int layoutIndex)
        {
            if (property != null)
            {
                guiIntField = new GUIIntField(new GUIContent(title));
                if (style != null)
                {
                    if (style.StepStyle != null && style.StepStyle.Step != 0)
                        guiIntField.Step = (int) style.StepStyle.Step;
                    if (style.RangeStyle != null)
                        guiIntField.SetRange((int) style.RangeStyle.Min, (int) style.RangeStyle.Max);
                }
                guiIntField.OnChanged += OnFieldValueChanged;
                guiIntField.OnConfirmed += () =>
                {
                    OnFieldValueConfirm();
                    StartUndo();
                };
                guiIntField.OnFocusLost += OnFieldValueConfirm;
                guiIntField.OnFocusGained += StartUndo;

                layout.AddElement(layoutIndex, guiIntField);
            }
        }

        /// <inheritdoc/>
        public override InspectableState Refresh(int layoutIndex)
        {
            if (guiIntField != null && !guiIntField.HasInputFocus)
                guiIntField.Value = property.GetValue<int>();

            InspectableState oldState = state;
            if (state.HasFlag(InspectableState.Modified))
                state = InspectableState.NotModified;

            return oldState;
        }

        /// <inheritdoc />
        public override void SetHasFocus(string subFieldName = null)
        {
            guiIntField.Focus = true;
        }

        /// <summary>
        /// Triggered when the user inputs a new integer value.
        /// </summary>
        /// <param name="newValue">New value of the int field.</param>
        private void OnFieldValueChanged(int newValue)
        {
            property.SetValue(newValue);
            state |= InspectableState.ModifyInProgress;
        }

        /// <summary>
        /// Triggered when the user confirms input in the integer field.
        /// </summary>
        private void OnFieldValueConfirm()
        {
            StartUndo();

            if(state.HasFlag(InspectableState.ModifyInProgress))
                state |= InspectableState.Modified;

            EndUndo();
        }
    }

    /** @} */
}