# notelen.py

"""
This module is an integeral part of the program 
MMA - Musical Midi Accompaniment.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

Bob van der Poel <bvdp@xplornet.com>
	

"""
import gbl
from   MMA.common import *


noteLenTable = {
	'0'	 : 1,                   # special 0==1 midi tick
	'1'	 : gbl.BperQ * 4,       # whole note
	'2'	 : gbl.BperQ * 2,       # 1/2
	'23' : gbl.BperQ * 4 / 3,   # 1/2 triplet
	'4'	 : gbl.BperQ,           # 1/4
	'43' : gbl.BperQ * 2 / 3,   # 1/4 triplet
	'8'	 : gbl.BperQ / 2,       # 1/8
	'81' : None,                # short 1/8 swing note
	'82' : None,                # long 1/8 swing note
	'16' : gbl.BperQ / 4,       # 1/16
	'32' : gbl.BperQ / 8,       # 1/32
	'64' : gbl.BperQ / 16,      # 1/64
	'6'	 : gbl.BperQ / 6,       # 1/16 note triplet
	'3'	 : gbl.BperQ / 3,       # 1/8 note triplet
	'5'	 : gbl.BperQ / 5 }      # 1/8 note quintuplet


def swingMode(ln):
	""" Enable/Disable Swing timing mode. """

	
	emsg = "Use: SwingMode [ On, Off, 0, 1 Skew=xx ]."
	
	if not ln:
		error(emsg)

	
	for v in ln:

		a = v.upper()

		if a in ("ON", "1"):
			gbl.swingMode = 1
			continue
		
		if a in ("OFF", "0"):
			gbl.swingMode = 0
			continue

		if a.find('=')>1:
			a,b = a.split('=')

			if a == 'SKEW':
				gbl.swingSkew = b
				v = int( stoi(b) * gbl.BperQ / 100)
				noteLenTable['81'] = v
				noteLenTable['82'] = gbl.BperQ - v
				continue

		error(emsg)

	if gbl.debug:
		print "SwingMode: Status=%s, Skew Note lengths: %s and %s ticks." % \
			  (gbl.swingMode, noteLenTable['81'], noteLenTable['82'])
		

swingMode(['Skew=66'])    # Set the default swingskew values.



def getNoteLen(n):	
	""" Convert a Note to a midi tick length. 
	
	Notes are 1==Whole, 4==Quarter, etc.
	Notes can be dotted or double dotted.
	Notes can be combined: 1+4 == 5 beats, 4. or 4+8 == dotted 1/4
                           1-4 == 3 beats, 1-0 == 4 beats less a midi tick
	"""
	
	length = 0
	
	n=n.replace('-', '+-')    # change "2-4" to "2+-4" for easier parsing
	n=n.replace('++-', '+-')  # and in case we already used "+-", take out 2nd "+"
	
	for a in str(n).split('+'):
		if a.endswith('..'):
			dot = 2
			a=a[:-2]
		elif a.endswith('.'):
			dot = 1
			a=a[:-1]
		else:
			dot = 0

		try:
			if a.startswith('-'):
				i = noteLenTable[a[1:]] * -1
			else:
				i = noteLenTable[a]

		except:
			error("Unknown note duration %s" % n )

		if dot == 2:
			i += i/2 + i/4
		elif dot == 1:
			i += i/2
		length += i
		
	return length