using System.Text;
using Microsoft.SqlServer.TransactSql.ScriptDom;
using System;
using System.Linq;
using System.Collections.Generic;

namespace SQLLinter.Infrastructure.Diagram;

public static class FragmentDiagramBuilder
{
    public static string RenderMermaid(TSqlFragment fragment)
    {
        if (fragment == null) return string.Empty;
        var diagram = BpmnBuilder.Build(fragment);
        return MermaidRenderer.RenderMarkdown(diagram);
    }

    public static string RenderHtmlSvg(TSqlFragment fragment)
    {
        if (fragment == null) return string.Empty;
        var diagram = BpmnBuilder.Build(fragment);
        // Use mermaid HTML instead of SVG fallback
        return MermaidRenderer.RenderHtml(diagram);
    }

    // keep helpers used by earlier code if needed
    private static string Escape(string s)
    {
        if (s == null) return string.Empty;
        return System.Net.WebUtility.HtmlEncode(s).Replace("\n", " ").Replace("\r", " ");
    }

    private static string Truncate(string s, int len)
    {
        if (s == null) return string.Empty;
        if (s.Length <= len) return s;
        return s.Substring(0, len - 3) + "...";
    }

    private static string SanitizeId(string s)
    {
        if (string.IsNullOrEmpty(s)) return "id";
        var sb = new StringBuilder();
        foreach (var ch in s)
        {
            if (char.IsLetterOrDigit(ch)) sb.Append(ch);
            else sb.Append('_');
        }
        return sb.ToString();
    }
}