using FastReport.Utils;
using System;
using System.Linq;
using System.Windows;
using System.Windows.Forms;

namespace FastReport.Design.RibbonDesigner
{
    internal class Ribbon : StackedPanel
    {
        public Designer Designer { get; }

        public void UpdateLayout()
        {
            if (control.ActualWidth == 0)
                return;

            var groups = Controls.OfType<RibbonGroup>().ToList();
            groups.Sort((x, y) => x.Priority.CompareTo(y.Priority));

            double width = this.Measure();

            // Collapses a single group. Returns true if a group found
            Func<Func<RibbonGroup, bool>, Action<RibbonGroup>, bool> Collapse = (condition, action) =>
            {
                var group = groups.Where(condition).FirstOrDefault();
                if (group != null)
                {
                    var w = group.GroupWidth;
                    action(group);
                    width += group.GroupWidth - w;
                    return true;
                }
                return false;
            };

            // Expands a single group. Returns true if a group found and is expanded with success
            Func<Func<RibbonGroup, bool>, Action<RibbonGroup>, bool> Expand = (condition, action) =>
            {
                foreach (var group in groups.Where(condition))
                {
                    var saveState = group.State;
                    var w = group.GroupWidth;
                    action(group);
                    width += group.GroupWidth - w;
                    
                    // check if we're not exceeding bounds
                    if (width > control.ActualWidth)
                    {
                        // too wide, roll back
                        width -= group.GroupWidth - w;
                        group.State = saveState;
                    }
                    else
                    {
                        return true;
                    }
                }
                return false;
            };
            
            Func<GroupPriority, bool> ExpandPriority = (priority) => Expand(x => x.State == GroupState.Collapsed && x.Priority == priority, x => x.State = GroupState.Reduced);
            Func<GroupState, bool> Has = (state) => groups.Where(x => x.State == state).Any();
            Func<GroupPriority, bool> HasPriority = (priority) => groups.Where(x => x.State == GroupState.Collapsed && x.Priority == priority).Any();


            while (true)
            {
                if (width > control.ActualWidth)
                {
                    // reduce groups
                    if (Collapse(x => x.State == GroupState.Normal, x => x.State = GroupState.Reduced))
                        continue;

                    // cannot reduce, try to collapse
                    if (Collapse(x => x.State != GroupState.Collapsed, x => x.State = GroupState.Collapsed))
                        continue;

                    // everything is in collapsed state, break
                }
                else if (width < control.ActualWidth)
                {
                    // try to expand collapsed groups by priority (high to low). If higher priority groups are not expanded completely, break 
                    if (Has(GroupState.Collapsed))
                    {
                        if (ExpandPriority(GroupPriority.High))
                            continue;

                        if (!HasPriority(GroupPriority.High))
                        {
                            if (ExpandPriority(GroupPriority.Medium))
                                continue;

                            if (!HasPriority(GroupPriority.Medium))
                            {
                                if (ExpandPriority(GroupPriority.Low))
                                    continue;
                            }
                        }
                    }

                    if (!Has(GroupState.Collapsed))
                    {
                        // we have no collapsed groups, try to expand reduced groups
                        if (Expand(x => x.State == GroupState.Reduced, x => x.State = GroupState.Normal))
                            continue;
                    }

                    // nothing to do, break
                }

                break;
            }
        }

        public void AddQuickAccessControls(MenuStrip menu)
        {
            var qaGroup = new RibbonQuickAccessGroup(Designer);
            bool compactMenu = Config.UseCompactMenu;
            menu.Parent.Controls.Insert(0, qaGroup.Panel);
            
            var ctl = qaGroup.Panel.control;
            ctl.Height = 22;
            ctl.VerticalAlignment = VerticalAlignment.Top;

            var menuCtl = menu.menu;
            menuCtl.Padding = new Thickness(5, 0, qaGroup.Panel.Measure(), 0);
            menuCtl.LayoutUpdated += (s, e) =>
            {
                var lastItem = menuCtl.Items[menuCtl.Items.Count - 1] as FrameworkElement;
                var pt = lastItem.TranslatePoint(new Point(lastItem.DesiredSize.Width, 0), menuCtl);
                if (RightToLeft == RightToLeft.Yes)
                    ctl.Margin = new Thickness(0, compactMenu ? 4 : 1, pt.X + 4, 0);
                else
                    ctl.Margin = new Thickness(pt.X + 4, compactMenu ? 4 : 1, 0, 0);
            };

            Designer.Plugins.Add(qaGroup);
        }

        public Ribbon(Designer designer)
        {
            Designer = designer;
            Vertical = false;
            control.Margin = new Thickness(4, 0, 0, 0);

            var stdGroup = new RibbonStandardGroup(designer);
            Controls.Add(stdGroup);
            Controls.Add(new ToolStripSeparator(true));

            var pageGroup = new RibbonPageGroup(designer);
            Controls.Add(pageGroup);
            Controls.Add(new ToolStripSeparator(true));

            var editGroup = new RibbonClipboardGroup(designer);
            Controls.Add(editGroup);
            Controls.Add(new ToolStripSeparator(true));

            var textGroup = new RibbonTextGroup(designer);
            Controls.Add(textGroup);
            Controls.Add(new ToolStripSeparator(true));

            var borderGroup = new RibbonBorderGroup(designer);
            Controls.Add(borderGroup);
            Controls.Add(new ToolStripSeparator(true));

            var styleGroup = new RibbonStyleGroup(designer);
            Controls.Add(styleGroup);
            Controls.Add(new ToolStripSeparator(true));

            var layoutGroup = new RibbonLayoutGroup(designer);
            Controls.Add(layoutGroup);
            Controls.Add(new ToolStripSeparator(true));

            var polyGroup = new RibbonPolygonGroup(designer);
            Controls.Add(polyGroup);

            Designer.Plugins.AddRange(new IDesignerPlugin[] {
                stdGroup, pageGroup, editGroup, textGroup, borderGroup, styleGroup, layoutGroup, polyGroup });

            this.control.SizeChanged += (s, e) =>
            {
                UpdateLayout();
            };
        }
    }
}