using FluentAssertions;
using StellaOps.Scanner.Reachability;
using Xunit;

namespace StellaOps.Reachability.FixtureTests;

public sealed class SymbolIdTests
{
    [Fact]
    public void ForJava_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForJava("com.example", "MyClass", "doSomething", "(Ljava/lang/String;)V");

        id.Should().StartWith("sym:java:");
        id.Should().HaveLength("sym:java:".Length + 43); // Base64url SHA-256 without padding = 43 chars
    }

    [Fact]
    public void ForJava_IsDeterministic()
    {
        var id1 = SymbolId.ForJava("com.example", "MyClass", "doSomething", "(Ljava/lang/String;)V");
        var id2 = SymbolId.ForJava("com.example", "MyClass", "doSomething", "(Ljava/lang/String;)V");

        id1.Should().Be(id2);
    }

    [Fact]
    public void ForJava_IsCaseInsensitive()
    {
        var id1 = SymbolId.ForJava("com.example", "MyClass", "doSomething", "()V");
        var id2 = SymbolId.ForJava("COM.EXAMPLE", "MYCLASS", "DOSOMETHING", "()V");

        id1.Should().Be(id2);
    }

    [Fact]
    public void ForDotNet_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForDotNet("MyAssembly", "MyNamespace", "MyClass", "MyMethod(System.String)");

        id.Should().StartWith("sym:dotnet:");
    }

    [Fact]
    public void ForDotNet_DifferentSignaturesProduceDifferentIds()
    {
        var id1 = SymbolId.ForDotNet("MyAssembly", "MyNamespace", "MyClass", "Method(String)");
        var id2 = SymbolId.ForDotNet("MyAssembly", "MyNamespace", "MyClass", "Method(Int32)");

        id1.Should().NotBe(id2);
    }

    [Fact]
    public void ForNode_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForNode("express", "lib/router", "function");

        id.Should().StartWith("sym:node:");
    }

    [Fact]
    public void ForNode_HandlesScopedPackages()
    {
        var id1 = SymbolId.ForNode("@angular/core", "src/render", "function");
        var id2 = SymbolId.ForNode("@angular/core", "src/render", "function");

        id1.Should().Be(id2);
        id1.Should().StartWith("sym:node:");
    }

    [Fact]
    public void ForGo_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForGo("github.com/example/repo", "pkg/http", "Server", "HandleRequest");

        id.Should().StartWith("sym:go:");
    }

    [Fact]
    public void ForGo_FunctionWithoutReceiver()
    {
        var id = SymbolId.ForGo("github.com/example/repo", "pkg/main", "", "main");

        id.Should().StartWith("sym:go:");
    }

    [Fact]
    public void ForRust_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForRust("my_crate", "foo::bar", "my_function", "_ZN8my_crate3foo3bar11my_functionE");

        id.Should().StartWith("sym:rust:");
    }

    [Fact]
    public void ForSwift_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForSwift("MyModule", "MyClass", "myMethod", null);

        id.Should().StartWith("sym:swift:");
    }

    [Fact]
    public void ForShell_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForShell("scripts/deploy.sh", "run_migration");

        id.Should().StartWith("sym:shell:");
    }

    [Fact]
    public void ForBinary_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForBinary("7f6e5d4c3b2a1908", ".text", "_start");

        id.Should().StartWith("sym:binary:");
    }

    [Fact]
    public void ForPython_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForPython("requests", "requests.api", "get");

        id.Should().StartWith("sym:python:");
    }

    [Fact]
    public void ForRuby_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForRuby("rails", "ActiveRecord::Base", "#save");

        id.Should().StartWith("sym:ruby:");
    }

    [Fact]
    public void ForPhp_CreatesCanonicalSymbolId()
    {
        var id = SymbolId.ForPhp("laravel/framework", "Illuminate\\Http", "Request::input");

        id.Should().StartWith("sym:php:");
    }

    [Fact]
    public void Parse_ValidSymbolId_ReturnsComponents()
    {
        var id = SymbolId.ForJava("com.example", "MyClass", "method", "()V");

        var result = SymbolId.Parse(id);

        result.Should().NotBeNull();
        result!.Value.Lang.Should().Be("java");
        result.Value.Fragment.Should().HaveLength(43);
    }

    [Fact]
    public void Parse_InvalidSymbolId_ReturnsNull()
    {
        SymbolId.Parse("invalid").Should().BeNull();
        SymbolId.Parse("sym:").Should().BeNull();
        SymbolId.Parse("sym:java").Should().BeNull();
        SymbolId.Parse("").Should().BeNull();
        SymbolId.Parse(null!).Should().BeNull();
    }

    [Fact]
    public void FromTuple_CreatesSymbolIdFromRawTuple()
    {
        var tuple = "my\0canonical\0tuple";
        var id = SymbolId.FromTuple("custom", tuple);

        id.Should().StartWith("sym:custom:");
    }

    [Fact]
    public void AllLanguagesAreDifferent()
    {
        // Same tuple data should produce different IDs for different languages
        var java = SymbolId.ForJava("pkg", "cls", "meth", "()V");
        var dotnet = SymbolId.ForDotNet("pkg", "cls", "meth", "()V");
        var node = SymbolId.ForNode("pkg", "cls", "meth");

        java.Should().NotBe(dotnet);
        dotnet.Should().NotBe(node);
        java.Should().NotBe(node);
    }
}