using FluentAssertions;
using Oms.Application.Shared;

namespace Oms.Tests;

public class CustomerCodeGeneratorTests
{
    private const string June2026Prefix = "AF";

    [Theory]
    [InlineData(1, "AF0A1")]
    [InlineData(12, "AF0B2")]
    [InlineData(100, "AF1A0")]
    [InlineData(999, "AF9J9")]
    [InlineData(1000, "AF0A0")]
    [InlineData(1001, "AF10A1")]
    [InlineData(1999, "AF19J9")]
    [InlineData(2000, "AF20A0")]
    [InlineData(10000, "AF90A0")]
    public void FormatSequence_ShouldMatchExpectedCode(int sequence, string expectedCode)
    {
        CustomerCodeGenerator.FormatSequence(sequence, June2026Prefix).Should().Be(expectedCode);
    }

    [Theory]
    [InlineData("AF0A1", 1)]
    [InlineData("AF0B2", 12)]
    [InlineData("AF1A0", 100)]
    [InlineData("AF9J9", 999)]
    [InlineData("AF0A0", 1000)]
    [InlineData("AF10A1", 1001)]
    [InlineData("AF19J9", 1999)]
    [InlineData("AF20A0", 2000)]
    [InlineData("AF90A0", 10000)]
    public void TryParseSequence_ShouldRoundTripFormattedCodes(string code, int expectedSequence)
    {
        CustomerCodeGenerator.TryParseSequence(code, June2026Prefix, out var sequence).Should().BeTrue();
        sequence.Should().Be(expectedSequence);
    }

    [Fact]
    public void BuildMonthPrefix_ShouldUseYearAndMonthLetters()
    {
        CustomerCodeGenerator.BuildMonthPrefix(new DateTime(2026, 6, 1)).Should().Be("AF");
        CustomerCodeGenerator.BuildMonthPrefix(new DateTime(2027, 1, 1)).Should().Be("BA");
    }
}