using ScadaLink.Commons.Messages.Management;
using ScadaLink.ManagementService;

namespace ScadaLink.ManagementService.Tests;

/// <summary>
/// Tests for <see cref="ManagementEndpoints"/> request-body parsing
/// (findings ManagementService-006 / -013).
/// </summary>
public class ManagementEndpointsTests
{
    [Fact]
    public void ParseCommand_WithExplicitPayload_DeserializesIntoCommandType()
    {
        var json = """{ "command": "CreateSite", "payload": { "name": "Site1", "siteIdentifier": "SITE1", "description": "Desc" } }""";

        var result = ManagementEndpoints.ParseCommand(json);

        Assert.True(result.Success);
        var command = Assert.IsType<CreateSiteCommand>(result.Command);
        Assert.Equal("Site1", command.Name);
        Assert.Equal("SITE1", command.SiteIdentifier);
        Assert.Equal("Desc", command.Description);
    }

    [Fact]
    public void ParseCommand_WithMissingPayload_DeserializesParameterlessCommand()
    {
        // No "payload" field at all -- the fallback must not allocate a throwaway
        // JsonDocument and must still produce a valid parameterless command.
        var json = """{ "command": "ListTemplates" }""";

        var result = ManagementEndpoints.ParseCommand(json);

        Assert.True(result.Success);
        Assert.IsType<ListTemplatesCommand>(result.Command);
    }

    [Fact]
    public void ParseCommand_WithInvalidJson_ReturnsFailure()
    {
        var result = ManagementEndpoints.ParseCommand("{ not json");

        Assert.False(result.Success);
        Assert.Equal("BAD_REQUEST", result.ErrorCode);
    }

    [Fact]
    public void ParseCommand_WithMissingCommandField_ReturnsFailure()
    {
        var result = ManagementEndpoints.ParseCommand("""{ "payload": {} }""");

        Assert.False(result.Success);
        Assert.Equal("BAD_REQUEST", result.ErrorCode);
    }

    [Fact]
    public void ParseCommand_WithUnknownCommand_ReturnsFailure()
    {
        var result = ManagementEndpoints.ParseCommand("""{ "command": "NoSuchCommand" }""");

        Assert.False(result.Success);
        Assert.Equal("BAD_REQUEST", result.ErrorCode);
    }
}
