using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;

namespace PamhagenSysCtrl.Helpers.Pipeline {
    public class Graph {

        public HashSet<INode> Nodes = [];
        public HashSet<IEdge> Edges = [];

        public Graph() {

        }

        public Pipe CreatePipe(INode start, INode end, bool verticalFirst = false) {
            Nodes.Add(start);
            Nodes.Add(end);
            var p = new Pipe(start, end, verticalFirst);
            start.Outputs.Add(p);
            end.Inputs.Add(p);
            Edges.Add(p);
            return p;
        }

        public Pipe CreateTwoWayPipe(INode n1, INode n2, bool verticalFirst = false) {
            Nodes.Add(n1);
            Nodes.Add(n2);
            var p = new Pipe(n1, n2, verticalFirst, twoWay: true);
            n1.Inputs.Add(p);
            n1.Outputs.Add(p);
            n2.Inputs.Add(p);
            n2.Outputs.Add(p);
            Edges.Add(p);
            return p;
        }

        public Inlet CreateInlet(INode start, ISink end) {
            Nodes.Add(start);
            Nodes.Add(end);
            var p = new Inlet(start, end, start.CenterX > end.CenterX);
            start.Outputs.Add(p);
            end.Inputs.Add(p);
            Edges.Add(p);
            return p;
        }

        public Outlet CreateOutlet(ISource start, INode end) {
            Nodes.Add(start);
            Nodes.Add(end);
            var p = new Outlet(start, end);
            start.Outputs.Add(p);
            end.Inputs.Add(p);
            Edges.Add(p);
            return p;
        }

        public Path? GetPath(INode start, INode end, Func<INode, bool>? valid = null) {
            if (!Nodes.Contains(start) || !Nodes.Contains(end)) throw new ArgumentException("Start/end node not contained in graph");
            valid ??= a => true;
            List<(IEdge, INode)> hops = [];
            Path? path = null;
            foreach (var o in start.Outputs) {
                if (o.End == end) {
                    return new(start, [(o, o.End)]);
                } else if (!valid(o.End) || (!o.IsTwoWay && o.End == start) || (o.IsTwoWay && o.End == start)) {
                    continue;
                }

                var p = GetPath(o.End, end, valid);
                if (p != null) {
                    var p2 = new Path(start, [(o, o.End), .. p.Value.Hops]);
                    if (path == null || p2.Length < path.Value.Length) {
                        path = p2;
                    }
                }
            }
            return path != null ? new(start, path.Value.Hops) : null;
        }

        public void Draw(Canvas canvas) {
            canvas.Children.Add(new Rectangle() {
                Fill = Brushes.White,
                Width = 5000,
                Height = 5000,
            });
            foreach (var e in Edges) {
                e.Draw(canvas);
            }
            foreach (var n in Nodes) {
                n.Draw(canvas);
            }
        }

        public ISet<INode> Update(double x, double y, bool down) {
            HashSet<INode> hover = new();
            foreach (var e in Edges) {
                e.Update();
            }
            foreach (var n in Nodes) {
                if (n.Update(x, y, down)) {
                    hover.Add(n);
                }
            }
            return hover;
        }
    }
}