using FastReport.Design.PageDesigners.Code;
using FastReport.Engine;
using FastReport.Utils;
using Microsoft.CodeAnalysis;
using RoslynPad.Editor;
using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace FastReport.WPF.RoslynPad
{
    internal class RoslynPadSyntaxEditor : SyntaxEditorBase
    {
        private RoslynCodeEditor editor;
        private Report report;
        private MyRoslynHost _host;
        private string oldPartialClass;

        public override string Text
        {
            get => RemovePartialKeyword(editor.Text);
            set => editor.Text = AddPartialKeyword(value);
        }

        public override string SelectedText
        {
            get => editor.SelectedText;
            set => editor.SelectedText = value;
        }

        public override bool Modified
        {
            get => editor.IsModified;
            set => editor.IsModified = value;
        }

        public override bool ShowLineNumbers
        {
            get => editor.ShowLineNumbers;
            set => editor.ShowLineNumbers = value;
        }

        public override bool EnableVirtualSpace
        {
            get => editor.Options.EnableVirtualSpace;
            set => editor.Options.EnableVirtualSpace = value;
        }

        public override bool ConvertTabsToSpaces
        {
            get => editor.Options.ConvertTabsToSpaces;
            set => editor.Options.ConvertTabsToSpaces = value;
        }

        public override int IndentationSize
        {
            get => editor.Options.IndentationSize;
            set => editor.Options.IndentationSize = value;
        }

        private SyntaxType syntaxType;
        public override SyntaxType SyntaxType
        {
            get => syntaxType;
            set
            {
                if (syntaxType != value)
                {
                    syntaxType = value;
                    InitDocument();
                }
            }
        }

        public override bool AllowCodeCompletion { get; set; }

        public override void Cut() => editor.Cut();

        public override void Copy() => editor.Copy();

        public override void Paste() => editor.Paste();

        public override bool CanUndo => editor.CanUndo;

        public override void Undo() => editor.Undo();

        public override bool CanRedo => editor.CanRedo;

        public override void Redo() => editor.Redo();

        public override void Select(int start, int length) => editor.Select(start, length);

        public override void SelectAll() => editor.SelectAll();

        public override void Focus()
        {
            Application.DoEvents();
            editor.Dispatcher.InvokeAsync(() => editor.Focus());
        }

        public override void Locate(int line, int column)
        {
            editor.CaretOffset = editor.Document.GetOffset(line, column);
        }

        public override void SetCaretFromMousePosition(System.Drawing.Point pos)
        {
            var textPos = editor.GetPositionFromPoint(new System.Windows.Point(pos.X / DpiScale, pos.Y / DpiScale));
            if (textPos != null)
            {
                Locate(textPos.Value.Line, textPos.Value.Column);
            }
        }

        public override void UpdateInternals(Report report)
        {
            this.report = report;

            string partialClass = MakePartialClass();
            if (partialClass != oldPartialClass)
            {
                oldPartialClass = partialClass;
                _host.SetAdditionalInfo(partialClass, report.ReferencedAssemblies);
            }
        }

        private void InitDocument()
        {
            _host = new MyRoslynHost(SyntaxType);
            editor.InitializeAsync(_host, new ClassificationHighlightColors(), Directory.GetCurrentDirectory(), string.Empty, SourceCodeKind.Regular);
        }

        private string MakePartialClass()
        {
            ObjectCollection allObjects = report.AllObjects;
            SortedList<string, Base> objects = new SortedList<string, Base>();
            StringBuilder partialClass = new StringBuilder(1000);

            AddClassHeader(partialClass);

            // add all report objects
            AddObject(partialClass, typeof(Report), "Report");
            AddObject(partialClass, typeof(ReportEngine), "Engine");
            foreach (Base c in allObjects)
            {
                if (!String.IsNullOrEmpty(c.Name) && !objects.ContainsKey(c.Name))
                    objects.Add(c.Name, c);
            }
            foreach (Base c in objects.Values)
            {
                AddObject(partialClass, c.GetType(), c.Name);
            }

            AddClassFooter(partialClass);

            return partialClass.ToString();
        }

        private void AddClassHeader(StringBuilder text)
        {
            if (SyntaxType == SyntaxType.Cs)
            {
                text.AppendLine("namespace FastReport {");
                text.AppendLine("partial class ReportScript {");
            }
            else
            {
                text.AppendLine("Namespace FastReport");
                text.AppendLine("Partial Class ReportScript");
            }
        }

        private void AddClassFooter(StringBuilder text)
        {
            if (SyntaxType == SyntaxType.Cs)
            {
                text.AppendLine("}}");
            }
            else
            {
                text.AppendLine("End Class");
                text.AppendLine("End Namespace");
            }
        }

        private void AddObject(StringBuilder text, Type type, string name)
        {
            if (SyntaxType == SyntaxType.Cs)
            {
                text.Append("public ").Append(type.FullName).Append(" ").Append(name).Append(";\r\n");
            }
            else
            {
                text.Append("public ").Append(name).Append(" as Global.").Append(type.FullName).Append("\r\n");
            }
        }

        private string AddPartialKeyword(string value)
        {
            if (SyntaxType == SyntaxType.Cs)
            {
                return value.Replace("public class ReportScript", "public partial class ReportScript");
            }
            return value.Replace("Public Class ReportScript", "Public Partial Class ReportScript");
        }

        private string RemovePartialKeyword(string value)
        {
            if (SyntaxType == SyntaxType.Cs)
            {
                return value.Replace("public partial class ReportScript", "public class ReportScript");
            }
            return value.Replace("Public Partial Class ReportScript", "Public Class ReportScript");
        }

        public RoslynPadSyntaxEditor()
        {
            editor = new RoslynCodeEditor();
            SetControl(editor);

            editor.HorizontalScrollBarVisibility = editor.VerticalScrollBarVisibility = System.Windows.Controls.ScrollBarVisibility.Auto;
            editor.Padding = new System.Windows.Thickness(4, 2, 0, 0);

            editor.TextChanged += (s, e) => OnTextChanged();
        }
    }

    public static class SyntaxEditor
    {
        public static void Register()
        {
            SyntaxEditorClass.Register(typeof(RoslynPadSyntaxEditor), SyntaxEditorKind.Code);
            Warmup();
        }

        private static async void Warmup()
        {
            await Task.Run(() => new MyRoslynHost(SyntaxType.Cs));
        }
    }
}