@page "/source-viewer"
@rendermode @(Microsoft.AspNetCore.Components.Web.RenderMode.InteractiveServer)
@using Microsoft.AspNetCore.Components
@using Microsoft.AspNetCore.WebUtilities
@inject IWebHostEnvironment Environment
@inject NavigationManager Navigation
@inject TrafagSalesExporter.Services.IUiTextService UiText

<PageTitle>@T("Source Viewer", "Source Viewer")</PageTitle>

<MudStack Spacing="2">
    <MudStack Row="true" Spacing="2" AlignItems="AlignItems.Center">
        <MudText Typo="Typo.h5">@T("Source Viewer", "Source Viewer")</MudText>
        <MudButton Variant="Variant.Outlined" Href="/transformations">
            @T("Zurueck zur Transformation", "Back to transformations")
        </MudButton>
    </MudStack>

    @if (!string.IsNullOrWhiteSpace(_requestedPath))
    {
        <MudText Typo="Typo.body2">
            @T("Datei:", "File:")
            <MudText Inline="true" Typo="Typo.body2"><code>@_requestedPath</code></MudText>
        </MudText>
    }

    @if (!string.IsNullOrWhiteSpace(_requestedType))
    {
        <MudText Typo="Typo.body2">
            @T("Klasse:", "Class:")
            <MudText Inline="true" Typo="Typo.body2"><code>@_requestedType</code></MudText>
            @if (_highlightLineNumber is not null)
            {
                <span> @T("bei Zeile", "at line") @_highlightLineNumber</span>
            }
        </MudText>
    }

    @if (!string.IsNullOrWhiteSpace(_error))
    {
        <MudAlert Severity="Severity.Error" Variant="Variant.Outlined">@_error</MudAlert>
    }
    else if (string.IsNullOrWhiteSpace(_content))
    {
        <MudProgressCircular Indeterminate="true" />
    }
    else
    {
        <MudPaper Class="pa-4">
            <div style="font-family: Consolas, monospace; font-size: 0.9rem;">
                @foreach (var line in _lines)
                {
                    <div id="@GetLineAnchor(line.Number)"
                         style="@GetLineStyle(line.Number)">
                        <span style="display:inline-block; width:4rem; color:#666;">@line.Number.ToString("0000")</span>
                        <span>@line.Text</span>
                    </div>
                }
            </div>
        </MudPaper>
        @if (_highlightLineNumber is not null)
        {
            <script>
                location.hash = '@GetLineAnchor(_highlightLineNumber.Value)';
            </script>
        }
    }
</MudStack>

@code {
    private string? _requestedPath;
    private string? _requestedType;
    private string? _content;
    private string? _error;
    private List<SourceLine> _lines = [];
    private int? _highlightLineNumber;

    protected override void OnInitialized()
    {
        var uri = Navigation.ToAbsoluteUri(Navigation.Uri);
        var query = QueryHelpers.ParseQuery(uri.Query);
        _requestedPath = query.TryGetValue("path", out var value) ? value.ToString() : null;
        _requestedType = query.TryGetValue("type", out var typeValue) ? typeValue.ToString() : null;

        if (string.IsNullOrWhiteSpace(_requestedPath))
        {
            _error = T("Kein Dateipfad angegeben.", "No file path provided.");
            return;
        }

        if (_requestedPath.Contains("..", StringComparison.Ordinal) || Path.IsPathRooted(_requestedPath))
        {
            _error = T("Ungueltiger Dateipfad.", "Invalid file path.");
            return;
        }

        var fullPath = Path.Combine(Environment.ContentRootPath, _requestedPath.Replace('/', Path.DirectorySeparatorChar));
        if (!File.Exists(fullPath))
        {
            _error = string.Format(T("Datei nicht gefunden: {0}", "File not found: {0}"), _requestedPath);
            return;
        }

        _content = File.ReadAllText(fullPath);
        _lines = _content
            .Replace("\r\n", "\n", StringComparison.Ordinal)
            .Split('\n')
            .Select((text, index) => new SourceLine(index + 1, text))
            .ToList();

        if (!string.IsNullOrWhiteSpace(_requestedType))
        {
            _highlightLineNumber = _lines
                .FirstOrDefault(x => x.Text.Contains($"class {_requestedType}", StringComparison.Ordinal) ||
                                     x.Text.Contains($"sealed class {_requestedType}", StringComparison.Ordinal) ||
                                     x.Text.Contains($"public class {_requestedType}", StringComparison.Ordinal) ||
                                     x.Text.Contains($"public sealed class {_requestedType}", StringComparison.Ordinal))
                ?.Number;
        }
    }

    private static string GetLineAnchor(int lineNumber) => $"line-{lineNumber}";

    private string GetLineStyle(int lineNumber)
    {
        var highlight = _highlightLineNumber == lineNumber;
        return highlight
            ? "background-color:#fff3cd; white-space:pre-wrap;"
            : "white-space:pre-wrap;";
    }

    private sealed record SourceLine(int Number, string Text);

    private string T(string german, string english) => UiText.Text(german, english);
}