/*
 *                     GNU AFFERO GENERAL PUBLIC LICENSE
 *                       Version 3, 19 November 2007
 *  Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 *  Everyone is permitted to copy and distribute verbatim copies
 *  of this license document, but changing it is not allowed.
 */

using Microsoft.CodeAnalysis.CSharp.Scripting;
using Microsoft.CodeAnalysis.Scripting;
using System;
using System.IO;
using System.Xml.Serialization;
using UVtools.Core.FileFormats;
using UVtools.Core.Scripting;

namespace UVtools.Core.Operations;


public sealed class OperationScripting : Operation
{
    #region Members

    public event EventHandler? OnScriptReload;
    private string? _filePath;
    private string? _scriptText;
    private ScriptState? _scriptState;

    #endregion

    #region Overrides

    public override bool CanRunInPartialMode => true;

    //public override bool CanHaveProfiles => false;
    public override string IconClass => "fa-solid fa-code";
    public override string Title => "Scripting";

    public override string Description =>
        $"Run external scripts to manipulate the loaded file.\n" +
        $"The scripts have wide access to your system and able to do modifications, read/write files, etc. " +
        $"Make sure to run only the scripts you trust! Or run UVtools in a sandbox while executing this.";

    public override string ConfirmationText =>
        $"run the {ScriptGlobals?.Script.Name} script from layers {LayerIndexStart} through {LayerIndexEnd}?";

    public override string ProgressTitle =>
        $"Scripting from layers {LayerIndexStart} through {LayerIndexEnd}";

    public override string ProgressAction => "Scripted layers";

    public override string? ValidateInternally()
    {
        if (!CanExecute)
        {
            if (ScriptGlobals is not null && About.Version.CompareTo(ScriptGlobals.Script.MinimumVersionToRun) >= 0)
            {
                return $"Unable to run due {About.Software} version {About.VersionStr} is lower than required {ScriptGlobals.Script.MinimumVersionToRun}\n" +
                       $"Please update {About.Software} in order to run this script.";
            }

            return "Script is not loaded.";
        }

        var scriptValidation = _scriptState!.ContinueWithAsync<string?>("return ScriptValidate();").Result;
        return scriptValidation.ReturnValue;
    }

    public override string ToString()
    {
        var result = $"[{Path.GetFileName(_filePath)}]" + LayerRangeString;
        if (!string.IsNullOrEmpty(ProfileName)) result = $"{ProfileName}: {result}";
        return result;
    }

    #endregion

    #region Enums

    #endregion

    #region Properties

    [XmlIgnore]
    public ScriptGlobals? ScriptGlobals { get; private set; }

    public string? FilePath
    {
        get => _filePath;
        set
        {
            if (value is null)
            {
                RaiseAndSetIfChanged(ref _filePath, null);
            }
            else
            {
                if (!value.EndsWith(".csx") && !value.EndsWith(".cs")) return;
                if (!File.Exists(value)) return;
                if (!RaiseAndSetIfChanged(ref _filePath, value)) return;
            }

            RaisePropertyChanged(nameof(HaveFile));
        }
    }

    [XmlIgnore]
    public string? ScriptText
    {
        get => _scriptText;
        set => RaiseAndSetIfChanged(ref _scriptText, value);
    }

    public bool CanExecute => !string.IsNullOrWhiteSpace(_filePath) && _scriptState is not null && ScriptGlobals is not null && About.Version.CompareTo(ScriptGlobals.Script.MinimumVersionToRun) >= 0;

    public bool HaveFile => !string.IsNullOrWhiteSpace(_filePath);

    /*public override string ToString()
    {
        var result = $"[{_infillType}] [Wall: {_wallThickness}px] [B: {_infillBrightness}px] [T: {_infillThickness}px] [S: {_infillSpacing}px]" + LayerRangeString;
        if (!string.IsNullOrEmpty(ProfileName)) result = $"{ProfileName}: {result}";
        return result;
    }*/



    #endregion

    #region Constructor

    public OperationScripting() { }

    public OperationScripting(FileFormat slicerFile) : base(slicerFile)
    { }

    #endregion

    #region Equality

    private bool Equals(OperationScripting other)
    {
        return _filePath == other._filePath;
    }

    public override bool Equals(object? obj)
    {
        return ReferenceEquals(this, obj) || obj is OperationScripting other && Equals(other);
    }

    public override int GetHashCode()
    {
        return (_filePath != null ? _filePath.GetHashCode() : 0);
    }

    #endregion

    #region Methods

    public void ReloadScriptFromFile(string? filePath = null)
    {
        if (!string.IsNullOrWhiteSpace(filePath)) FilePath = filePath;
        if (string.IsNullOrWhiteSpace(_filePath) || !File.Exists(_filePath)) return;
        ReloadScriptFromText(File.ReadAllText(_filePath));
    }

    public void ReloadScriptFromText(string? text = null)
    {
        if (!string.IsNullOrWhiteSpace(text)) ScriptText = text;
        if (string.IsNullOrWhiteSpace(_scriptText)) return;

        ScriptText = ScriptParser.ParseScriptFromText(_scriptText);

        ScriptGlobals = new ScriptGlobals { SlicerFile = SlicerFile, Operation = this };

       _scriptState = CSharpScript.RunAsync(_scriptText,
            ScriptOptions.Default
                .AddReferences(typeof(About).Assembly)
                .WithAllowUnsafe(true),
            ScriptGlobals).Result;
        var result = _scriptState.ContinueWithAsync("ScriptInit();").Result;
        
        RaisePropertyChanged(nameof(CanExecute));
        OnScriptReload?.Invoke(this, EventArgs.Empty);
    }

    protected override bool ExecuteInternally(OperationProgress progress)
    {
        if (ScriptGlobals is null || _scriptState is null) return false;
        ScriptGlobals.Progress = progress;
        var scriptExecute = _scriptState.ContinueWithAsync<bool>("return ScriptExecute();").Result;
        return !progress.Token.IsCancellationRequested && scriptExecute.ReturnValue;
    }

    #endregion
}