namespace MeetingAssistant.Speakers;

internal static class SpeakerIdentityTranscriptAudit
{
    public static Task AppendIdentifiedAsync(
        IEnumerable<SpeakerIdentityReference> references,
        string speakerLabel,
        string name,
        CancellationToken cancellationToken)
    {
        return AppendAsync(
            references,
            $"{DateTimeOffset.Now:yyyy-MM-dd} {speakerLabel} was identified as {name}",
            cancellationToken);
    }

    public static Task AppendMergedAsync(
        IEnumerable<SpeakerIdentityReference> references,
        string name1,
        string name2,
        CancellationToken cancellationToken)
    {
        return AppendAsync(
            references,
            $"{DateTimeOffset.Now:yyyy-MM-dd} {name1} and {name2} were merged",
            cancellationToken);
    }

    private static async Task AppendAsync(
        IEnumerable<SpeakerIdentityReference> references,
        string line,
        CancellationToken cancellationToken)
    {
        foreach (var transcriptPath in references
            .Select(reference => reference.TranscriptPath)
            .Where(path => !string.IsNullOrWhiteSpace(path))
            .Distinct(StringComparer.OrdinalIgnoreCase))
        {
            if (!File.Exists(transcriptPath))
            {
                continue;
            }

            var existing = await File.ReadAllTextAsync(transcriptPath, cancellationToken);
            if (existing.Contains(line, StringComparison.OrdinalIgnoreCase))
            {
                continue;
            }

            var separator = existing.EndsWith(Environment.NewLine, StringComparison.Ordinal)
                ? ""
                : Environment.NewLine;
            await File.AppendAllTextAsync(
                transcriptPath,
                $"{separator}{line}{Environment.NewLine}",
                cancellationToken);
        }
    }
}