using System;
using System.IO;
using System.Collections.Generic;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using DevExpress.AIIntegration.Blazor.Chat;
using Microsoft.Extensions.AI;
using UglyToad.PdfPig;

namespace DXChatApplication {
    public partial class MainWindow {
        static readonly IReadOnlyList<AIChatResource> Resources = new List<AIChatResource> {
            new AIChatResource(
                "access.txt",
                "Access Log",
                GetLogResourceAsync,
                "text/plain",
                "Contains web server access records collected over the last 24 hours."
                ),
            new AIChatResource(
                "restaurantmenu.pdf",
                "Restaurant Menu",
                GetPdfResourceAsync,
                "application/pdf",
                "Displays New York Steakhouse's current menu."
                ),
            new AIChatResource(
                "dashboard.jpg",
                "Dashboard (Screenshot)",
                GetImageResourceAsync,
                "image/jpeg",
                "A dashboard screenshot that displays the latest real-time analytics data."
                ),
            new AIChatResource(
                "dxaichat.md",
                "AI Chat Documentation",
                GetDocsResourceAsync,
                "text/markdown",
                "Includes reference documentation that describes AI Chat functionality and usage guidelines."
                )
        };
        public MainWindow() {
            InitializeComponent();
            aiChatControl.ChatResources = Resources;
        }
        // Load a text log file and return it as a single text content block.
        static async Task<IList<AIContent>> GetLogResourceAsync(AIChatResource resource, CancellationToken ct) {
            if (!File.Exists(resource.Uri))
                return new List<AIContent> { new TextContent("Log file not found.") };

            string text = await File.ReadAllTextAsync(resource.Uri, ct).ConfigureAwait(false);
            return new List<AIContent> { new TextContent(text) };
        }

        // Load an image file as binary content.
        static async Task<ReadOnlyMemory<byte>> GetImageResourceAsync(AIChatResource resource, CancellationToken ct) {
            if (!File.Exists(resource.Uri))
                return ReadOnlyMemory<byte>.Empty;

            byte[] data = await File.ReadAllBytesAsync(resource.Uri, ct).ConfigureAwait(false);
            return new ReadOnlyMemory<byte>(data);
        }

        // Load markdown documentation as a string.
        static async Task<string> GetDocsResourceAsync(AIChatResource resource, CancellationToken ct) {
            if (!File.Exists(resource.Uri))
                return "Documentation file not found.";

            return await File.ReadAllTextAsync(resource.Uri, ct).ConfigureAwait(false);
        }

        // Extract all text from a PDF file using the PdfPig library.
        static async Task<string> GetPdfResourceAsync(AIChatResource resource, CancellationToken ct) {
            if (!File.Exists(resource.Uri))
                return "PDF file not found.";

            return await Task.Run(() => {
                var sb = new StringBuilder();
                try {
                    using var pdf = PdfDocument.Open(resource.Uri);
                    foreach (var page in pdf.GetPages()) {
                        sb.AppendLine(page.Text);
                    }
                }
                catch (Exception ex) {
                    return $"[Error reading PDF: {ex.Message}]";
                }
                return sb.ToString();
            }, ct).ConfigureAwait(false);
        }
    }
}

Imports System
Imports System.IO
Imports System.Collections.Generic
Imports System.Text
Imports System.Threading
Imports System.Threading.Tasks
Imports DevExpress.AIIntegration.Blazor.Chat
Imports Microsoft.Extensions.AI
Imports UglyToad.PdfPig

Namespace DXChatApplication
    Partial Public Class MainWindow
        Private Shared ReadOnly Resources As IReadOnlyList(Of AIChatResource) = New List(Of AIChatResource) From {
            New AIChatResource(
                "access.txt",
                "Access Log",
                AddressOf GetLogResourceAsync,
                "text/plain",
                "Contains web server access records collected over the last 24 hours."
            ),
            New AIChatResource(
                "restaurantmenu.pdf",
                "Restaurant Menu",
                AddressOf GetPdfResourceAsync,
                "application/pdf",
                "Displays New York Steakhouse's current menu."
            ),
            New AIChatResource(
                "dashboard.jpg",
                "Dashboard (Screenshot)",
                AddressOf GetImageResourceAsync,
                "image/jpeg",
                "A dashboard screenshot that displays the latest real-time analytics data."
            ),
            New AIChatResource(
                "dxaichat.md",
                "AI Chat Documentation",
                AddressOf GetDocsResourceAsync,
                "text/markdown",
                "Includes reference documentation that describes AI Chat functionality and usage guidelines."
            )
        }

        Public Sub New()
            InitializeComponent()
            aiChatControl.ChatResources = Resources
        End Sub

        ' Load a text log file and return it as a single text content block.
        Private Shared Async Function GetLogResourceAsync(resource As AIChatResource, ct As CancellationToken) As Task(Of IList(Of AIContent))
            If Not File.Exists(resource.Uri) Then
                Return New List(Of AIContent) From {New TextContent("Log file not found.")}
            End If

            Dim text As String = Await File.ReadAllTextAsync(resource.Uri, ct).ConfigureAwait(False)
            Return New List(Of AIContent) From {New TextContent(text)}
        End Function

        ' Load an image file as binary content.
        Private Shared Async Function GetImageResourceAsync(resource As AIChatResource, ct As CancellationToken) As Task(Of ReadOnlyMemory(Of Byte))
            If Not File.Exists(resource.Uri) Then
                Return ReadOnlyMemory(Of Byte).Empty
            End If

            Dim data As Byte() = Await File.ReadAllBytesAsync(resource.Uri, ct).ConfigureAwait(False)
            Return New ReadOnlyMemory(Of Byte)(data)
        End Function

        ' Load markdown documentation as a string.
        Private Shared Async Function GetDocsResourceAsync(resource As AIChatResource, ct As CancellationToken) As Task(Of String)
            If Not File.Exists(resource.Uri) Then
                Return "Documentation file not found."
            End If

            Return Await File.ReadAllTextAsync(resource.Uri, ct).ConfigureAwait(False)
        End Function

        ' Extract all text from a PDF file using the PdfPig library.
        Private Shared Async Function GetPdfResourceAsync(resource As AIChatResource, ct As CancellationToken) As Task(Of String)
            If Not File.Exists(resource.Uri) Then
                Return "PDF file not found."
            End If

            Return Await Task.Run(Function()
                    Dim sb As New StringBuilder()
                    Try
                        Using pdf = PdfDocument.Open(resource.Uri)
                            For Each page In pdf.GetPages()
                                sb.AppendLine(page.Text)
                            Next
                        End Using
                    Catch ex As Exception
                        Return $"[Error reading PDF: {ex.Message}]"
                    End Try
                    Return sb.ToString()
                End Function, ct).ConfigureAwait(False)
        End Function
    End Class
End Namespace