using WxAgent.Core;
using Xunit;

namespace WxAgent.Core.Tests;

public sealed class WechatAttachmentInputTests
{
    [Fact]
    public void PrepareFilePathsRejectsOutOfRangeBatchesBeforeAnySend()
    {
        var single = Assert.Throws<WxAgentException>(() => WechatAttachmentInput.PrepareFilePaths(["one.txt"]));
        var tooMany = Assert.Throws<WxAgentException>(() => WechatAttachmentInput.PrepareFilePaths(
            Enumerable.Repeat("unused.txt", WechatAttachmentInput.MaxBatchSize + 1).ToArray()));

        Assert.Equal(WxAgentErrorCode.InvalidArgument, single.Code);
        Assert.Equal(WxAgentErrorCode.InvalidArgument, tooMany.Code);
    }

    [Fact]
    public void PrepareFilePathsValidatesEveryFileBeforeReturningCanonicalPaths()
    {
        var directory = Directory.CreateTempSubdirectory();
        try
        {
            var first = Path.Combine(directory.FullName, "first.pdf");
            var second = Path.Combine(directory.FullName, "second.png");
            File.WriteAllText(first, "first");
            File.WriteAllText(second, "second");

            var paths = WechatAttachmentInput.PrepareFilePaths([first, second]);

            Assert.Equal([Path.GetFullPath(first), Path.GetFullPath(second)], paths);
            Assert.True(WechatAttachmentInput.IsImagePath(second));
            Assert.True(WechatAttachmentInput.IsImagePath("photo.JPEG"));
            Assert.False(WechatAttachmentInput.IsImagePath(first));
        }
        finally
        {
            directory.Delete(recursive: true);
        }
    }

    [Fact]
    public void PrepareFilePathsRejectsASecondMissingFileBeforeSendingTheFirst()
    {
        var directory = Directory.CreateTempSubdirectory();
        try
        {
            var first = Path.Combine(directory.FullName, "first.pdf");
            File.WriteAllText(first, "first");

            var exception = Assert.Throws<WxAgentException>(() => WechatAttachmentInput.PrepareFilePaths(
                [first, Path.Combine(directory.FullName, "missing.pdf")]));

            Assert.Equal(WxAgentErrorCode.InvalidArgument, exception.Code);
        }
        finally
        {
            directory.Delete(recursive: true);
        }
    }
}