#
# Render a tune represented using ABC notation.
#

from SimpleGraphics import *
from math import log2
from time import sleep

#  Evaluate a value that might be a whole number or a fraction.  Such values
#  show up as note lengths and as a description of the unit note length.
#
#  Parameters:
#    s: A string the contains either a whole number or a fraction such as "1/4"
#       or "2"
#
#  Returns: The floating point value of either the whole number or the
#           fraction.
#
def evaluateFraction(s):
  if "/" in s:   # It's a fraction...
    # Separate the numerator from the denominator and convert each to a float.
    parts = s.split("/")  
    numerator = float(parts[0])
    denominator = float(parts[1])
    
    # Evaluate the fraction and return the result.
    return numerator / denominator

  else:  # It's not a fraction, so just return the value as a float.
    return float(s)

#
# Draw a staff with a treble clef, and 10 pixels between adjancent lines.
# The staff will fill the width of the window, leaving 50 pixels on the
# left and right edges of it.  TrebleCelf_71.gif must be stored in the
# same folder as the .py file.
#
# Parameters:
#   y: The vertical position of the top line of the staff.
#
# Returns: (None)
#
def drawStaff(y):
  for i in range(5):
    line(50, y + i * 10, getWidth() - 50, y + i * 10)

  treble_clef_image = loadImage("TrebleClef_71.gif")
  drawImage(treble_clef_image, 60, y - 16)

#
#  Draw a music note with a hollow or filled head, stem, flag and dot as needed
#  for its duration.
#
#  Parameters:
#    x, y: The location of the center of the head of the note.
#    duration: The duration of the note as a floating-point number.  Supported 
#              durations are 0.125, 0.25, 0.375, 0.5, 0.75, and 1.0.
#    inspace:  True if the note resides in the space between two staff lines,
#              False if the note is on a line.
#    upstem:   True if the note should be drawn with its stem extending up
#              from the head of the note, False if the stem should extend
#              downward.
#    color:    The color of the note as a named color.
#
def drawNote(x, y, duration, inspace=True, upstem=True, color="black"):
  assert(x >= 0 and x <= getWidth())
  assert(y >= 0 and y <= getHeight())
  assert(duration in [1/8, 1/4, 3/8, 1/2, 3/4, 1])
  assert(inspace == True or inspace == False)
  assert(upstem == True or upstem == False)

  # Set the outline color.
  setOutline(color)
  
  # Set the fill color so that the note is either open or filled, depending on
  # what is needed for its duration.
  if duration <= 3 / 8:
    setFill(color)
  else:
    setFill(None)

  # Draw the head of the note.
  ellipse(x-7, y-5, 14, 11)

  # These additional ellipses increase the weight of the line around the head
  # of open notes.
  ellipse(x-6, y-5, 12, 11)
  ellipse(x-7, y-4, 14, 9)

  # Draw the stem of the note (if needed, and in the correct direction).
  if duration < 1:  # The note needs a stem...
    if upstem == False:  # It's a down stem...
      line(x-7, y, x-7, y+35)

      # Does the note get a flag?
      if duration <= 1 / 8:
        #curve(x-7, y+35, x-7, y+25, x-15, y+15, x-11, y+5)
        curve(x-7, y+35, x-7, y+25, x+3, y+16, x-1, y+7)

    else:  # It's an up stem...
      line(x+6, y, x+6, y-35)
      
      # Does the note get a flag?
      if duration <= 1 / 8:
        curve(x+7, y-35, x+7, y-25, x+15, y-15, x+11, y-5)

  # Does the note need a dot?
  if duration == 3/8 or duration == 3/4:
    setFill(color)
    # Does the dot get drawn vertically centered on the note because it is in
    # a space, or slightly above center to avoid being on a line?
    if inspace == True:
      ellipse(x + 11, y - 2, 4, 4)
    else:
      ellipse(x + 11, y - 5, 4, 4)