/*
 * Greenshot - a free and open source screenshot tool
 * Copyright (C) 2007-2014 Thomas Braun, Jens Klingen, Robin Krom
 *
 * For more information see: http://getgreenshot.org/
 * The Greenshot project is hosted on Sourceforge: http://sourceforge.net/projects/greenshot/
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 1 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

using Greenshot.Drawing.Fields;
using Greenshot.Helpers;
using Greenshot.Plugin;
using Greenshot.Plugin.Drawing;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Text;
using System.Runtime.Serialization;
using System.Windows.Forms;

namespace Greenshot.Drawing
{
    /// <summary>
    /// Description of SpeechbubbleContainer.
    /// </summary>
    [Serializable]
    public class SpeechbubbleContainer : TextContainer
    {
        #region TargetGripper serializing code

        // Only used for serializing the TargetGripper location
        private Point _storedTargetGripperLocation;

        /// <summary>
        /// Store the current location of the target gripper
        /// </summary>
        /// <param name="context"></param>
        [OnSerializing]
        private void SetValuesOnSerializing(StreamingContext context)
        {
            if (TargetGripper != null)
            {
                _storedTargetGripperLocation = TargetGripper.Location;
            }
        }

        /// <summary>
        /// Restore the target gripper
        /// </summary>
        /// <param name="context"></param>
        [OnDeserialized]
        private void SetValuesOnDeserialized(StreamingContext context)
        {
            InitTargetGripper(Color.Green, _storedTargetGripperLocation);
        }

        #endregion TargetGripper serializing code

        public SpeechbubbleContainer(Surface parent)
            : base(parent)
        {
        }

        /// <summary>
        /// We set our own field values
        /// </summary>
        protected override void InitializeFields()
        {
            AddField(GetType(), FieldType.LINE_THICKNESS, 2);
            AddField(GetType(), FieldType.LINE_COLOR, DefaultLineColor);
            AddField(GetType(), FieldType.SHADOW, false);
            AddField(GetType(), FieldType.FONT_ITALIC, false);
            AddField(GetType(), FieldType.FONT_BOLD, false);
            AddField(GetType(), FieldType.FILL_COLOR, Color.White);
            AddField(GetType(), FieldType.FONT_FAMILY, FontFamily.GenericSansSerif.Name);
            AddField(GetType(), FieldType.FONT_SIZE, 20f);
            AddField(GetType(), FieldType.TEXT_HORIZONTAL_ALIGNMENT, StringAlignment.Center);
            AddField(GetType(), FieldType.TEXT_VERTICAL_ALIGNMENT, VerticalAlignment.CENTER);
        }

        protected override void TargetGripperMove(int absX, int absY)
        {
            base.TargetGripperMove(absX, absY);
            Invalidate();
        }

        /// <summary>
        /// Called from Surface (the _parent) when the drawing begins (mouse-down)
        /// </summary>
        /// <returns>true if the surface doesn't need to handle the event</returns>
        public override bool HandleMouseDown(int mouseX, int mouseY)
        {
            if (TargetGripper == null)
            {
                InitTargetGripper(Color.Yellow, new Point(mouseX, mouseY));
            }
            return base.HandleMouseDown(mouseX + 20, mouseY + 20);
        }

        public override Rectangle DrawingBounds
        {
            get
            {
                // TODO: Use the normal bounds and extend with the TargetGripper
                return new Rectangle(0, 0, _parent.Width, _parent.Height);
            }
        }

        public override void Draw(Graphics graphics, RenderMode renderMode)
        {
            if (TargetGripper == null)
            {
                return;
            }
            graphics.SmoothingMode = SmoothingMode.HighQuality;
            graphics.InterpolationMode = InterpolationMode.HighQualityBicubic;
            graphics.CompositingQuality = CompositingQuality.HighQuality;
            graphics.PixelOffsetMode = PixelOffsetMode.None;
            graphics.TextRenderingHint = TextRenderingHint.AntiAliasGridFit;

            Color lineColor = GetFieldValueAsColor(FieldType.LINE_COLOR);
            Color fillColor = GetFieldValueAsColor(FieldType.FILL_COLOR);
            int lineThickness = GetFieldValueAsInt(FieldType.LINE_THICKNESS);

            bool lineVisible = (lineThickness > 0 && Colors.IsVisible(lineColor));
            Rectangle rect = GuiRectangle.GetGuiRectangle(Left, Top, Width, Height);

            if (Selected && renderMode == RenderMode.EDIT)
            {
                DrawSelectionBorder(graphics, rect);
            }

            int tailAngle = 90 + (int)GeometryHelper.Angle2D(rect.Left + (rect.Width / 2), rect.Top + (rect.Height / 2), TargetGripper.Left, TargetGripper.Top);
            int tailLength = GeometryHelper.Distance2D(rect.Left + (rect.Width / 2), rect.Top + (rect.Height / 2), TargetGripper.Left, TargetGripper.Top);
            int tailWidth = (Math.Abs(rect.Width) + Math.Abs(rect.Height)) / 20;

            GraphicsPath bubble = new GraphicsPath();
            // adapt corner radius to small rectangle dimensions
            int smallerSideLength = Math.Min(rect.Width, rect.Height);
            int cornerRadius = smallerSideLength > 60 ? 30 : smallerSideLength / 2;
            if (cornerRadius > 5)
            {
                Rectangle bubbleRect = GuiRectangle.GetGuiRectangle(0, 0, rect.Width, rect.Height);
                bubbleRect = Rectangle.Inflate(bubbleRect, -lineThickness, -lineThickness);
                bubble.AddArc(bubbleRect.X, bubbleRect.Y, cornerRadius, cornerRadius, 180, 90);
                bubble.AddArc(bubbleRect.X + bubbleRect.Width - cornerRadius, bubbleRect.Y, cornerRadius, cornerRadius, 270, 90);
                bubble.AddArc(bubbleRect.X + bubbleRect.Width - cornerRadius, bubbleRect.Y + bubbleRect.Height - cornerRadius, cornerRadius, cornerRadius, 0, 90);
                bubble.AddArc(bubbleRect.X, bubbleRect.Y + bubbleRect.Height - cornerRadius, cornerRadius, cornerRadius, 90, 90);
            }

            //bubble.AddRectangle(GuiRectangle.GetGuiRectangle(0, 0, rect.Width, rect.Height));
            //bubble.AddEllipse(0, 0, Math.Abs(rect.Width), Math.Abs(rect.Height));
            bubble.CloseAllFigures();

            GraphicsPath tail = new GraphicsPath();
            tail.AddLine(-tailWidth, 0, tailWidth, 0);
            tail.AddLine(tailWidth, 0, 0, -tailLength);
            tail.CloseFigure();

            GraphicsState state = graphics.Save();
            // draw the tail border where the bubble is not visible
            using (Region clipRegion = new Region(bubble))
            {
                clipRegion.Translate(rect.Left, rect.Top);
                graphics.SetClip(clipRegion, CombineMode.Exclude);
                graphics.TranslateTransform(rect.Left + (rect.Width / 2), rect.Top + (rect.Height / 2));
                graphics.RotateTransform(tailAngle);
                using (Pen pen = new Pen(lineColor, lineThickness))
                {
                    graphics.DrawPath(pen, tail);
                }
            }
            graphics.Restore(state);

            if (Colors.IsVisible(fillColor))
            {
                //draw the bubbleshape
                state = graphics.Save();
                graphics.TranslateTransform(rect.Left, rect.Top);
                using (Brush brush = new SolidBrush(fillColor))
                {
                    graphics.FillPath(brush, bubble);
                }
                graphics.Restore(state);
            }

            if (lineVisible)
            {
                //draw the bubble border
                state = graphics.Save();
                // Draw bubble where the Tail is not visible.
                using (Region clipRegion = new Region(tail))
                {
                    using (Matrix transformMatrix = new Matrix())
                    {
                        transformMatrix.Rotate(tailAngle);
                        clipRegion.Transform(transformMatrix);
                    }
                    clipRegion.Translate(rect.Left + (rect.Width / 2), rect.Top + (rect.Height / 2));
                    graphics.SetClip(clipRegion, CombineMode.Exclude);
                    graphics.TranslateTransform(rect.Left, rect.Top);
                    using (Pen pen = new Pen(lineColor, lineThickness))
                    {
                        //pen.EndCap = pen.StartCap = LineCap.Round;
                        graphics.DrawPath(pen, bubble);
                    }
                }
                graphics.Restore(state);
            }

            if (Colors.IsVisible(fillColor))
            {
                // Draw the tail border
                state = graphics.Save();
                graphics.TranslateTransform(rect.Left + (rect.Width / 2), rect.Top + (rect.Height / 2));
                graphics.RotateTransform(tailAngle);
                using (Brush brush = new SolidBrush(fillColor))
                {
                    graphics.FillPath(brush, tail);
                }
                graphics.Restore(state);
            }

            // cleanup the paths
            bubble.Dispose();
            tail.Dispose();

            // Draw the text
            UpdateFormat();
            DrawText(graphics, rect, lineThickness, ControlPaint.Dark(lineColor, 0.1f), false, StringFormat, Text, Font);
        }

        public override bool Contains(int x, int y)
        {
            double xDistanceFromCenter = x - (Left + Width / 2);
            double yDistanceFromCenter = y - (Top + Height / 2);
            // ellipse: x^2/a^2 + y^2/b^2 = 1
            return Math.Pow(xDistanceFromCenter, 2) / Math.Pow(Width / 2, 2) + Math.Pow(yDistanceFromCenter, 2) / Math.Pow(Height / 2, 2) < 1;
        }

        public override bool ClickableAt(int x, int y)
        {
            Rectangle rect = GuiRectangle.GetGuiRectangle(Left, Top, Width, Height);
            int lineThickness = GetFieldValueAsInt(FieldType.LINE_THICKNESS);
            int lineThicknessPlusSafety = lineThickness + 10;

            // If we clicked inside the rectangle and it's visible we are clickable at.
            Color fillColor = GetFieldValueAsColor(FieldType.FILL_COLOR);
            if (!Color.Transparent.Equals(fillColor))
            {
                if (Contains(x, y))
                {
                    return true;
                }
            }

            // check the rest of the lines
            if (lineThicknessPlusSafety > 0)
            {
                using (Pen pen = new Pen(Color.White, lineThicknessPlusSafety))
                {
                    using (GraphicsPath path = new GraphicsPath())
                    {
                        path.AddEllipse(rect);
                        return path.IsOutlineVisible(x, y, pen);
                    }
                }
            }
            else
            {
                return false;
            }
        }
    }
}