using Unity.Pipeline.Commands;
using Unity.Pipeline.Console;
using Unity.Pipeline.Models;

namespace Unity.Pipeline.Runtime.Commands
{
    /// <summary>
    /// Returns captured Unity console output. Backs the CLI's
    /// <c>console [--tail N] [--level log|warn|error] [--follow]</c>.
    ///
    /// Lives in the runtime assembly, so it is available from both the Editor and player builds —
    /// console capture is driven by <see cref="ConsoleLogCapture"/>, which runs in both contexts.
    ///
    /// The package has no streaming transport (the HTTP server handles one request at a time), so
    /// <c>--follow</c> is realized client-side: the CLI polls this command, prints new entries, and
    /// passes the returned <see cref="ConsoleLogResponse.Cursor"/> back as <c>since</c> on the next
    /// call. The flag mapping is:
    ///   --tail N             -> tail
    ///   --level X            -> level   (minimum severity threshold)
    ///   --follow             -> repeated calls with since = previous cursor
    ///
    /// Reads only the in-memory buffer (no Unity main-thread APIs), so it is marked
    /// <c>MainThreadRequired = false</c> for fast polling.
    /// </summary>
    public static class ConsoleCommand
    {
        /// <summary>Default number of entries returned when <c>tail</c> is not supplied.</summary>
        public const int DefaultTail = 100;

        [CliCommand("console", "Get captured Unity console output (Editor or Player; supports tail, level filtering, and follow via a cursor)", MainThreadRequired = false)]
        public static ConsoleLogResponse GetConsole(
            [CliArg("tail", "Maximum number of most-recent entries to return")] int tail = DefaultTail,
            [CliArg("level", "Minimum severity to include: log | warn | error")] string level = ConsoleLogBuffer.LevelLog,
            [CliArg("since", "Cursor: only return entries newer than this seq. Use the 'cursor' from a previous response to follow.")] long since = -1)
        {
            // Guard against nonsensical tail values; <= 0 would otherwise mean "unlimited" in the
            // buffer, which is not what a caller passing e.g. --tail 0 expects.
            if (tail <= 0)
                tail = DefaultTail;

            var minSeverity = ConsoleLogBuffer.SeverityFromLevelName(level);
            return ConsoleLogCapture.Buffer.Query(since, tail, minSeverity);
        }
    }
}