using FastReport.Utils;
using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

namespace FastReport.Controls
{
    internal class ToolStripZoomControl : ToolStripItem
    {
        private bool hlButton1;
        private bool hlButton2;
        private bool hlButton3;
        private bool hlMinus;
        private bool hlPlus;
        private bool movingSlider;

        private int Minimum { get; set; }
        private int Maximum { get; set; }

        private int _value;
        private int Value
        {
            get => _value;
            set
            {
                if (value < Minimum)
                    value = Minimum;
                if (value > Maximum)
                    value = Maximum;

                _value = value;
                
                ValueChanged?.Invoke(this, EventArgs.Empty);
                Invalidate();
            }
        }

        public float ZoomValue
        {
            get
            {
                float val = Value;
                if (val < 100)
                    val = val * 0.75f + 25;
                else
                    val = (val - 100) * 4 + 100;
                return val / 100f;
            }
            set
            {
                if (value < 1)
                    value = (value - 0.25f) / 0.75f;
                else if (value > 1)
                    value = (value - 1) / 4 + 1;
                Value = (int)Math.Round(value * 100);
            }
        }

        private int Step { get; set; }

        private UIStyle style;
        public UIStyle UIStyle
        {
            get => style;
            set
            {
                style = value;
                Invalidate();
            }
        }

        public event EventHandler ValueChanged;
        public event EventHandler ZoomPageWidthClick;
        public event EventHandler ZoomWholePageClick;
        public event EventHandler Zoom100Click;

        private void PaintBackground(Graphics g)
        {
            Rectangle rect = new Rectangle(0, 0, Width, Height);
            var colorTable = UIStyleUtils.GetColorTable(UIStyle);
            using (var brush = new LinearGradientBrush(rect, colorTable.Workspace.ZoomControl.GradientBegin, colorTable.Workspace.ZoomControl.GradientEnd, 90))
                g.FillRectangle(brush, rect);
            using (var pen = new Pen(colorTable.GripDark))
                g.DrawLine(pen, 0, 0, 0, Height);
            using (var pen = new Pen(colorTable.GripLight))
                g.DrawLine(pen, 1, 0, 1, Height);
        }

        private void PaintHighlight(Graphics g, Rectangle rect)
        {
            int _22 = Owner.LogicalToDevice(22);
            var colorTable = UIStyleUtils.GetColorTable(UIStyle);
            using (var brush = new LinearGradientBrush(rect, colorTable.ButtonSelectedGradientBegin, colorTable.ButtonSelectedGradientEnd, 90))
                g.FillRectangle(brush, rect);
            using (var pen = new Pen(colorTable.ButtonSelectedHighlightBorder, (int)Math.Round(Owner.LogicalToDevice(1f))))
                g.DrawRectangle(pen, rect);
        }

        private void PaintButton(Graphics g, int imageIndex, int x, int baseLine, bool highlight)
        {
            var bmp = Owner.GetImage(imageIndex);
            if (highlight)
            {
                int _22 = Owner.LogicalToDevice(22);
                PaintHighlight(g, new Rectangle(x, baseLine - _22 / 2, _22, _22));
            }
            
            int _3 = Owner.LogicalToDevice(3);
            int _16 = Owner.LogicalToDevice(16);
            g.DrawImage(bmp, new Rectangle(x + _3, baseLine - _16 / 2, _16, _16));
        }

        private void PaintText(Graphics g, int x)
        {
            Color foreColor = UIStyleUtils.GetColorTable(UIStyle).Workspace.ZoomControl.Foreground;
            TextRenderer.DrawText(g, ((int)(Math.Round(ZoomValue * 100))).ToString() + "%", 
                Font, new Rectangle(x, 0, Owner.LogicalToDevice(40), Height), foreColor, TextFormatFlags.Left | TextFormatFlags.VerticalCenter);
        }

        private void PaintSlider(Graphics g, int x, int baseLine)
        {
            int btnSize = Owner.LogicalToDevice(11);
            int thumb = Owner.LogicalToDevice(5);
            int gap = Owner.LogicalToDevice(20);
            int padRight = Owner.LogicalToDevice(8);
            int _1 = (int)Math.Round(Owner.LogicalToDevice(1f));
            int _2 = _1 + _1;
            int _3 = Owner.LogicalToDevice(3) + 1;
            int _6 = Owner.LogicalToDevice(6) + 1;
            int y = baseLine;

            var colorTable = UIStyleUtils.GetColorTable(UIStyle);
            Color foreColor = colorTable.Workspace.ZoomControl.Foreground;
            Color altColor = Color.Black;

            Pen p = new Pen(foreColor, _1);
            Pen p1 = new Pen(altColor, _1);
            Brush b = new SolidBrush(foreColor);
            Brush b1 = new SolidBrush(altColor);

            // minus
            if (hlMinus)
                PaintHighlight(g, new Rectangle(x - _3, y - btnSize / 2 - _3, btnSize + _6, btnSize + _6));
            g.DrawLine(hlMinus ? p1 : p, x, y, x + btnSize - 1, y);

            // line
            x += gap;
            g.DrawLine(p, x, y, Width - gap - padRight, y);

            // thumb
            int lineWidth = Width - gap - padRight - x;
            int pos = lineWidth * (Value - Minimum) / (Maximum - Minimum) + x;
            g.FillRectangle(b, pos - thumb / 2, y - btnSize / 2, thumb, btnSize);
            g.FillRectangle(b1, pos - thumb / 2 + _1, y - btnSize / 2 + _1, thumb - _2, btnSize - _2);

            // plus
            x = Width - padRight - btnSize;
            if (hlPlus)
                PaintHighlight(g, new Rectangle(x - _3, y - btnSize / 2 - _3, btnSize + _6, btnSize + _6));
            g.DrawLine(hlPlus? p1 : p, x, y, x + btnSize - 1, y);
            g.DrawLine(hlPlus ? p1 : p, x + btnSize / 2, y - btnSize / 2, x + btnSize / 2, y + btnSize / 2);

            p.Dispose();
            p1.Dispose();
            b.Dispose();
            b1.Dispose();
        }

        private void ResetHighlight()
        {
            hlButton1 = false;
            hlButton2 = false;
            hlButton3 = false;
            hlMinus = false;
            hlPlus = false;
        }

        protected override void OnPaint(PaintEventArgs e)
        {
            Graphics g = e.Graphics;
            PaintBackground(g);

            int gap = Owner.LogicalToDevice(6);
            int btnSize = Owner.LogicalToDevice(22);
            int textSize = Owner.LogicalToDevice(40);

            int x = gap;
            int baseLine = Height / 2;

            PaintButton(g, 235, x, baseLine, hlButton1);
            x += btnSize;
            PaintButton(g, 236, x, baseLine, hlButton2);
            x += btnSize;
            PaintButton(g, 237, x, baseLine, hlButton3);

            x += btnSize + gap;
            PaintText(g, x);

            x += textSize + gap;
            PaintSlider(g, x, baseLine);
        }

        protected override void OnMouseDown(MouseEventArgs e)
        {
            base.OnMouseDown(e);

            int padRight = Owner.LogicalToDevice(8);
            int gap = Owner.LogicalToDevice(6);
            int btnSize = Owner.LogicalToDevice(22);
            int textSize = Owner.LogicalToDevice(40);
            int lineGap = Owner.LogicalToDevice(20);

            int mouseX = e.X;
            if (Config.IsRunningOnMono)
            {
                mouseX -= this.Bounds.Left;
            }

            movingSlider = false;

            if (e.Button == MouseButtons.Left)
            {
                // slider area
                int lineStart = gap * 3 + btnSize * 3 + textSize + lineGap;
                int lineWidth = Width - padRight - lineGap - lineStart;
                if (mouseX >= lineStart && mouseX <= lineStart + lineWidth)
                {
                    Value = (mouseX - lineStart) * (Maximum - Minimum) / lineWidth + Minimum;
                    movingSlider = true;
                }
            }
        }

        protected override void OnMouseMove(MouseEventArgs e)
        {
            base.OnMouseMove(e);

            int padRight = Owner.LogicalToDevice(8);
            int gap = Owner.LogicalToDevice(6);
            int btnSize = Owner.LogicalToDevice(22);
            int textSize = Owner.LogicalToDevice(40);
            int sz = Owner.LogicalToDevice(11);
            int lineGap = Owner.LogicalToDevice(20);
            int baseLine = Height / 2;
            int _3 = Owner.LogicalToDevice(3);

            int mouseX = e.X;
            int mouseY = e.Y;
            if (Config.IsRunningOnMono)
            {
                mouseX -= this.Bounds.Left;
            }

            ResetHighlight();
            
            if (movingSlider)
            {
                // slider area
                int lineStart = gap * 3 + btnSize * 3 + textSize + lineGap;
                int lineWidth = Width - padRight - lineGap - lineStart;
                if (mouseX >= lineStart && mouseX <= lineStart + lineWidth)
                {
                    Value = (mouseX - lineStart) * (Maximum - Minimum) / lineWidth + Minimum;
                }
            }
            else
            {
                int x = gap;
                if (mouseY > baseLine - btnSize / 2 && mouseY < baseLine + btnSize / 2)
                {
                    // hit test buttons
                    hlButton1 = mouseX > x && mouseX < x + btnSize;
                    x += btnSize;
                    hlButton2 = mouseX > x && mouseX < x + btnSize;
                    x += btnSize;
                    hlButton3 = mouseX > x && mouseX < x + btnSize;

                    // hit text + -
                    x = gap * 3 + btnSize * 3 + textSize;
                    hlMinus = mouseX > x - _3 && mouseX < x + sz + _3;
                    x = Width - padRight - sz;
                    hlPlus = mouseX > x - _3 && mouseX < x + sz + _3;
                }
            }

            Invalidate();
        }

        protected override void OnMouseUp(MouseEventArgs e)
        {
            base.OnMouseUp(e);

            if (e.Button == MouseButtons.Left)
            {
                if (hlButton1)
                    ZoomPageWidthClick?.Invoke(this, EventArgs.Empty);
                else if (hlButton2)
                    ZoomWholePageClick?.Invoke(this, EventArgs.Empty);
                else if (hlButton3)
                    Zoom100Click?.Invoke(this, EventArgs.Empty);
                else if (hlMinus)
                    Value -= Step;
                else if (hlPlus)
                    Value += Step;
            }

            movingSlider = false;
            ResetHighlight();
            Invalidate();
        }

        protected override void OnMouseLeave(EventArgs e)
        {
            base.OnMouseLeave(e);
            ResetHighlight();
            Invalidate();
        }

        public ToolStripZoomControl()
        {
            Maximum = 200;
            Value = 100;
            Step = 5;
            AutoSize = false;
        }
    }
}