using Microsoft.CodeAnalysis;
using ResourceString.Net.Logic.Factories;
using ResourceString.Net.Logic.Parsers.Resx;

namespace ResourceString.Net;

[Generator]
public class Generator : IIncrementalGenerator
{
    public void Initialize(IncrementalGeneratorInitializationContext initContext)
    {
        // find all additional files that end with .txt
        var resxFiles = initContext.AdditionalTextsProvider.Where(static file => file.Path.EndsWith(".resx"));
        var assemblies = initContext.CompilationProvider.Select(static (c, _) => c.Assembly);

        // read their contents and save their name
        var config = resxFiles.Combine(assemblies).Select(
            (t, cancellationToken) => (
                name: System.IO.Path.GetFileNameWithoutExtension(t.Left.Path),
                content: t.Left.GetText(cancellationToken)!.ToString(),
                assembly: t.Right,
                path: t.Left.Path
            )
        );

        // generate a class that contains their values as const strings
        initContext.RegisterSourceOutput(config, (spc, t) =>
        {
            Parser.TryParse(t.content).IfSome(v =>
            {
                var relativeNamespace = System.IO.Path.GetDirectoryName(t.path).Substring(
                    System.IO.Path.GetDirectoryName(t.assembly.Locations[0].GetLineSpan().Path).Length
                ).Trim(System.IO.Path.DirectorySeparatorChar).Replace(System.IO.Path.DirectorySeparatorChar, '.');

                var ns = string.IsNullOrWhiteSpace(relativeNamespace)
                    ? t.assembly.Name
                    : $"{t.assembly.Name}.{relativeNamespace}";

                var resourceFileName = t.name;
                var className = CodeSnippetFactory.TransformToClassName(t.name);
                var snippet = CodeSnippetFactory.CreateResourceClassCodeSnippet(
                    CodeSnippetFactory.TransformToNamespace(ns),
                    className,
                    CodeSnippetFactory.CreateResourceMangerMemberCodeSnippet(
                        $"{ns}.{resourceFileName}",
                        className
                    ),
                    v.Resources
                );

                spc.AddSource($"{ns}.{className}", snippet.Value);
            });
        });
    }
}