using System;
using System.Collections.Generic;
using System.Diagnostics.Metrics;
using System.Linq;
using System.Text;
using System.Threading.Channels;
using System.Threading.Tasks;

namespace RushMidiLibrary {
    public struct MidiShortMessage {
        public UIntPtr dwParam1;
        public UIntPtr dwParam2;
        public MidiShortMessage(UIntPtr dwParam1, UIntPtr dwParam2) {
            this.dwParam1 = dwParam1;
            this.dwParam2 = dwParam2;
        }

        public bool IsNoteOn {
            get { return ((int)dwParam1 & 0xf0) == 0x90; }
        }

        public void GetNoteOn(out MidiChannel channel, out int noteId, out int velocity, out uint timestamp) {
            channel = (MidiChannel)((int)dwParam1 & 0x0f);
            noteId = ((int)dwParam1 & 0xff00) >> 8;
            velocity = ((int)dwParam1 & 0xff0000) >> 16;
            timestamp = (uint)dwParam2;
        }

        public bool IsNoteOff {
            get { return ((int)dwParam1 & 0xf0) == 0x80; }
        }

        public void GetNoteOff(out MidiChannel channel, out int noteId, out int velocity, out uint timestamp) {
            channel = (MidiChannel)((int)dwParam1 & 0x0f);
            noteId = ((int)dwParam1 & 0xff00) >> 8;
            velocity = ((int)dwParam1 & 0xff0000) >> 16;
            timestamp = (uint)dwParam2;
        }

        public bool IsControlChange {
            get { return ((int)dwParam1 & 0xf0) == 0xB0; }
        }

        public void GetControlChange(out MidiChannel channel, out MidiControl control, out int value, out uint timestamp) {
            channel = (MidiChannel)((int)dwParam1 & 0x0f);
            control = (MidiControl)(((int)dwParam1 & 0xff00) >> 8);
            value = ((int)dwParam1 & 0xff0000) >> 16;
            timestamp = (uint)dwParam2;
        }

        public bool IsProgramChange {
            get { return ((int)dwParam1 & 0xf0) == 0xC0; }
        }

        public void DecodeProgramChange(out MidiChannel channel, out MidiInstrument instrument, out uint timestamp) {
            channel = (MidiChannel)((int)dwParam1 & 0x0f);
            instrument = (MidiInstrument)(((int)dwParam1 & 0xff00) >> 8);
            timestamp = (uint)dwParam2;
        }

        public bool IsPitchBend {
            get { return ((int)dwParam1 & 0xf0) == 0xE0; }
        }

        public void GetPitchBend(out MidiChannel channel, out int value, out uint timestamp) {
            channel = (MidiChannel)((int)dwParam1 & 0x0f);
            value = ((((int)dwParam1 >> 9) & 0x3f80) | (((int)dwParam1 >> 8) & 0x7f));
            timestamp = (uint)dwParam2;
        }

        public bool IsRealTime {
            get { return ((int)dwParam1 & 0xf8) == 0xF8; }
        }

        public void GetRealTime(out MidiRealTimeMessageType msgType, out uint timestamp) {
            int messageType = (int)dwParam1 & 0x07;
            switch (messageType) {
                case 0:
                    msgType = MidiRealTimeMessageType.TimingClock;
                    break;
                case 2:
                    msgType = MidiRealTimeMessageType.Start;
                    break;
                case 3:
                    msgType = MidiRealTimeMessageType.Continue;
                    break;
                case 4:
                    msgType = MidiRealTimeMessageType.Stop;
                    break;
                case 6:
                    msgType = MidiRealTimeMessageType.ActiveSensing;
                    break;
                case 7:
                    msgType = MidiRealTimeMessageType.SystemReset;
                    break;
                case 1:
                case 5:
                    msgType = MidiRealTimeMessageType.Undefined;
                    break;
                default:
                    throw new ArgumentException("Unknown realtime message");
            }
            timestamp = (uint)dwParam2;
        }
    }
}