using ExtractMethod.Tooling;
using Microsoft.CodeAnalysis;

// CLIs are boring on purpose: argument parsing and printing live here, all
// Roslyn logic lives in Tooling/ so the tests can drive it directly.

string usage = "usage: ExtractMethod <file.cs> <startLine> <endLine>  (1-based, inclusive)";

if (args.Length != 3)
{
    Console.Error.WriteLine(usage);
    return 2;
}

string file = Path.GetFullPath(args[0]);
if (!File.Exists(file))
{
    Console.Error.WriteLine($"error: file not found: {file}");
    Console.Error.WriteLine(usage);
    return 2;
}

if (!int.TryParse(args[1], out int startLine) || !int.TryParse(args[2], out int endLine))
{
    Console.Error.WriteLine($"error: line numbers must be integers");
    Console.Error.WriteLine(usage);
    return 2;
}

// 1. parse the file
var tree = CompilationLoader.ParseFile(file);

// 2. build the scratch compilation (refs from TRUSTED_PLATFORM_ASSEMBLIES)
var compilation = CompilationLoader.CreateCompilation(tree, Path.GetFileNameWithoutExtension(file));
if (compilation.GetDiagnostics().Any(d => d.Severity == DiagnosticSeverity.Error))
{
    Console.Error.WriteLine("warning: the file does not compile cleanly under a plain Roslyn compilation; reporting syntax-level resolution only");
}

// 3. snap the range to whole statements, report cleanly otherwise
var report = SelectionResolver.Resolve(tree, startLine, endLine);
if (!report.Succeeded)
{
    Console.Error.WriteLine($"error: {report.Error}");
    return SelectionResolver.ExitError;
}

Console.WriteLine(
    $"{report.Count} statement(s) selected, lines {report.StartLine}..{report.EndLine} " +
    $"in {report.Method?.Identifier.ValueText}(): " +
    string.Join(", ", report.Kinds));

// 4. classify the data flow into the raw buckets (em 02: no pretty report yet)
// A classification failure is a semantic resolution error: same exit code as
// the resolver, message on stderr, but never a stack trace.
ExtractionSuggestion suggestion;
try
{
    suggestion = DataFlowClassifier.Classify(compilation.GetSemanticModel(tree), report);
}
catch (Exception e) when (e is InvalidOperationException or ArgumentException)
{
    Console.Error.WriteLine($"error: data-flow analysis failed: {e.Message}");
    return SelectionResolver.ExitError;
}

foreach (var param in suggestion.Params)
{
    Console.WriteLine($"params: {param.Name} ({param.Type}){(param.ByRef ? " [ref]" : " [in]")}");
}
if (suggestion.Params.Count == 0)
{
    Console.WriteLine("params: (none)");
}

foreach (var name in suggestion.Returns)
{
    Console.WriteLine($"returns: {name}");
}
if (suggestion.Returns.Count == 0)
{
    Console.WriteLine("returns: (none)");
}

foreach (var name in suggestion.Locals)
{
    Console.WriteLine($"locals: {name}");
}
if (suggestion.Locals.Count == 0)
{
    Console.WriteLine("locals: (none)");
}

return 0;