using w4c_workflows.Services.Execution;
using Xunit;

namespace w4c_workflows.Tests;

public class ExecutionContractTests
{
    [Fact]
    public void TaskInvocation_parses_a_full_job_field_set()
    {
        var fields = new Dictionary<string, string>
        {
            ["type"] = "task.run",
            ["run_id"] = "run-1",
            ["task_id"] = "task-1",
            ["task_key"] = "validate",
            ["language"] = "python",
            ["entry_file"] = "validate.py",
            ["entry_function"] = "main",
            ["env"] = "{\"FOO\":\"bar\"}",
            ["input"] = "{\"n\":5}",
            ["working_dir"] = "/tmp/wf",
            ["tenant_id"] = "t1",
            ["attempt"] = "2",
        };

        var inv = TaskInvocation.FromFields(fields);

        Assert.Equal("task.run", inv.Type);
        Assert.Equal("run-1", inv.RunId);
        Assert.Equal("validate", inv.TaskKey);
        Assert.Equal("python", inv.Language);
        Assert.Equal("validate.py", inv.EntryFile);
        Assert.Equal("main", inv.EntryFunction);
        Assert.Equal("bar", inv.Env["FOO"]);
        Assert.Equal("{\"n\":5}", inv.Input);
        Assert.Equal("/tmp/wf", inv.WorkingDir);
        Assert.Equal("t1", inv.TenantId);
        Assert.Equal(2, inv.Attempt);
    }

    [Fact]
    public void TaskInvocation_defaults_attempt_and_optional_fields()
    {
        var fields = new Dictionary<string, string>
        {
            ["type"] = "task.run",
            ["run_id"] = "r",
            ["task_id"] = "t",
            ["task_key"] = "k",
            ["language"] = "shell",
            ["entry_file"] = "a.sh",
            ["tenant_id"] = "t1",
        };

        var inv = TaskInvocation.FromFields(fields);

        Assert.Equal(1, inv.Attempt);
        Assert.Null(inv.EntryFunction);
        Assert.Null(inv.Input);
        Assert.Empty(inv.Env);
    }

    [Fact]
    public void TaskInvocation_rejects_missing_required_field()
    {
        var fields = new Dictionary<string, string> { ["type"] = "task.run" };
        Assert.Throws<InvalidOperationException>(() => TaskInvocation.FromFields(fields));
    }

    [Fact]
    public void TaskResultMessage_round_trips_result_fields()
    {
        var inv = Invocation.For("shell", "a.sh", input: "{\"x\":1}");
        var result = new ExecutionResult(
            true, 0, "out", "err", "{\"ok\":true}", null, TimeSpan.FromMilliseconds(123));

        var fields = TaskResultMessage.ToFields(inv, result);

        Assert.Equal("task.result", fields["type"]);
        Assert.Equal("run-1", fields["run_id"]);
        Assert.Equal("succeeded", fields["status"]);
        Assert.Equal("0", fields["exit_code"]);
        Assert.Equal("{\"ok\":true}", fields["output"]);
        Assert.False(fields.ContainsKey("error"));
    }

    [Fact]
    public void TaskResultMessage_includes_error_on_failure()
    {
        var inv = Invocation.For("shell", "a.sh");
        var result = new ExecutionResult(
            false, 3, string.Empty, "boom", null, "boom", TimeSpan.FromMilliseconds(10));

        var fields = TaskResultMessage.ToFields(inv, result);

        Assert.Equal("failed", fields["status"]);
        Assert.Equal("3", fields["exit_code"]);
        Assert.Equal("boom", fields["error"]);
        Assert.False(fields.ContainsKey("output"));
    }
}