using System;
using System.Collections.Generic;
using System.Linq;
using Melanchall.DryWetMidi.Smf;
using Melanchall.DryWetMidi.Smf.Interaction;

using SBRL.Utilities;

namespace MusicBoxConverter
{
    public class MusicBoxScoreGenerator
    {
		public bool Debug { get; set; } = false;

		public Vector2 Offset { get; set; } = new Vector2(10, 10);
		public Vector2 ScaleFactor { get; set; } = new Vector2(0.03f, 4f);

		public float HoleSize { get; set; } = 1f;

		public Vector2 ArrowSize { get; set; } = new Vector2(25, 25);
		public float ArrowSpacing { get; set; } = 50f;
		public float ArrowStrokeWidth { get; set; } = 8;
		public string ArrowColour { get; set; } = "#dacef3";

        private int trackLength;
        public int TrackLength
        {
            get
            {
                if (trackLength == 0)
                    trackLength = (int)AllNotes().Max((Note arg) => arg.Time);
                return trackLength;
            }
        }

		public int MaxNoteNumber {
			get {
				return SelectedMusicBox.HighestNote.NoteNumber;
			}
		}
		public int MinNoteNumber {
			get
			{
				return SelectedMusicBox.LowestNote.NoteNumber;
			}
		}

		public MusicBox SelectedMusicBox { get; private set; }

		private MidiFile midiFile;
		
		public MusicBoxScoreGenerator(string filename, MusicBox inMusicBox)
		{
            SelectedMusicBox = inMusicBox;
			midiFile = MidiFile.Read(filename);

			// Set the scale factor based on the strip height of the music box
			ScaleFactor = new Vector2(
				ScaleFactor.X,
				SelectedMusicBox.StripHeightMm / (SelectedMusicBox.NoteCount-1)
			);

            foreach(Note note in AllNotes()) {
                if (!SelectedMusicBox.IsValidNote(note))
                    Console.Error.WriteLine($"Warning: The note {note} at {note.Time} can't be played by the {SelectedMusicBox}.");
            }
		}
		
		public void SetScaleFactorX(float scaleFactorX) {
			Vector2 newScaleFactor = ScaleFactor;
			newScaleFactor.X = scaleFactorX;
			ScaleFactor = newScaleFactor;
		}
		
		public void SetScaleFactorY(float scaleFactorY) {
			Vector2 newScaleFactor = ScaleFactor;
			newScaleFactor.Y = scaleFactorY;
			ScaleFactor = newScaleFactor;
		}

		public void Output(string destinationFilename)
		{
			Console.WriteLine($"DEBUG SF {ScaleFactor}");
			Vector2 area = new Vector2(TrackLength, SelectedMusicBox.NoteCount-1).Multiply(ScaleFactor);
			Vector2 size = area.Add(Offset.Multiply(2));

			SvgWriter svg = new SvgWriter(
				destinationFilename,
				$"{size.X}mm", $"{size.Y}mm"
			) {
				UnitSuffix = "mm"
			};

			// Draw directional arrows down the score
			for (float i = 0; i < area.X; i += ArrowSpacing)
			{
				Vector2 arrowPos = new Vector2(i, area.Y / 2 + Offset.Y);

				svg.WriteLine(
					arrowPos.Subtract(ArrowSize),
					arrowPos,
					ArrowColour,
					ArrowStrokeWidth
				);
				svg.WriteLine(
					arrowPos,
					arrowPos.Subtract(new Vector2(ArrowSize.X, -ArrowSize.Y)),
					ArrowColour,
					ArrowStrokeWidth
				);
			}


			// Draw a marker at the beginning of the score
			svg.WriteRectangle(
				new Vector2(Offset.X / 2, Offset.Y),
				new Vector2(Offset.X / 2, area.Y),
				"#ffa500", -1,
				true
			);

			svg.WriteCircle(
				new Vector2((Offset.X * 3) / 4, Offset.Y * 1.25f),
				HoleSize,
				"#ff0077"
			);
			svg.WriteCircle(
				new Vector2((Offset.X * 3) / 4, Offset.Y + area.Y - Offset.Y * 0.25f),
				HoleSize * 2,
				"#0077ff"
			);




			// Draw the note lines
			for (float i = 0; i < area.Y; i += ScaleFactor.Y) {
				Vector2 start = Offset.Add(new Vector2(0, i));
				svg.WriteLine(start, start.Add(new Vector2(area.X, 0)), "darkgreen", 0.75f);
			}

			// Draw a red box around everything
			svg.WriteRectangle(Offset, area, "red", 0.75f);


			int noteIndex = 0;
			foreach (Note note in AllNotes())
			{
				if(Debug) {
					Console.WriteLine(
						$"[Note] {note.Time}: " +
							$"{note.NoteName}{note.Octave}/{note.NoteNumber} " +
							$"-> {SelectedMusicBox.NoteToBoxNumber(note)}"
					);
				}

				Vector2 holePosition = new Vector2(
					Offset.X + note.Time * ScaleFactor.X,
					Offset.Y + ((SelectedMusicBox.NoteCount - 1) - SelectedMusicBox.NoteToBoxNumber(note)) * ScaleFactor.Y
				);

				svg.WriteCircle(
					holePosition,
					HoleSize // radius
				);

				svg.WritePlus(
					holePosition,
					new Vector2(HoleSize, HoleSize).Multiply(1.5f)
				);

				svg.WriteText(
					holePosition.Subtract(new Vector2(-HoleSize * 2, HoleSize/2 + -svg.FontSizeRegular/2)),
					$"{noteIndex}",
					"regular"
				);

				noteIndex++;
			}

			svg.Complete();
		}

		public IEnumerable<Note> AllNotes()
		{
			foreach(TrackChunk chunk in midiFile.Chunks.OfType<TrackChunk>())
			{
				using(NotesManager notesManager = new NotesManager(chunk.Events))
				{
					foreach(Note note in notesManager.Notes)
						yield return note;
				}
			}
		}
	}
}