# Run the current pattern for a given number of steps (using current
# step size) and create a plot of population vs time in separate layer.
# Author: Andrew Trevorrow (andrew@trevorrow.com), May 2007.

import golly as g
from glife import getminbox, rect, rccw
from glife.text import make_text
from time import time

# --------------------------------------------------------------------

# size of plot
xlen = 500        # length of x axis
ylen = 500        # length of y axis

# --------------------------------------------------------------------

# draw a line of cells from x1,y1 to x2,y2 using Bresenham's algorithm
def draw_line(x1, y1, x2, y2):
   g.setcell(x1, y1, 1)
   if x1 == x2 and y1 == y2: return
   
   dx = x2 - x1
   ax = abs(dx) * 2
   sx = 1
   if dx < 0: sx = -1
   dy = y2 - y1
   ay = abs(dy) * 2
   sy = 1
   if dy < 0: sy = -1
   
   if ax > ay:
      d = ay - (ax / 2)
      while x1 != x2:
         g.setcell(x1, y1, 1)
         if d >= 0:
            y1 += sy
            d -= ax
         x1 += sx
         d += ay
   else:
      d = ax - (ay / 2)
      while y1 != y2:
         g.setcell(x1, y1, 1)
         if d >= 0:
            x1 += sx
            d -= ay
         y1 += sy
         d += ax
   
   g.setcell(x2, y2, 1)

# --------------------------------------------------------------------

# fit pattern in viewport if not empty and not completely visible
def fit_if_not_visible():
   try:
      r = rect(g.getrect())
      if (not r.empty) and (not r.visible()): g.fit()
   except:
      # getrect failed because pattern is too big
      g.fit()

# --------------------------------------------------------------------

if g.empty(): g.exit("There is no pattern.")

# check that a layer is available for population plot
layername = "population plot"
poplayer = -1
for i in xrange(g.numlayers()):
   if g.getname(i) == layername:
      poplayer = i
      break
if poplayer == -1 and g.numlayers() == g.maxlayers():
   g.exit("You need to delete a layer.")

# prompt user for number of steps
numsteps = xlen
s = g.getstring("Enter the number of steps:",
                str(numsteps), "Population plotter")
if len(s) > 0: numsteps = int(s)
if numsteps <= 0: g.exit()

# generate pattern for given number of steps
poplist = [ int(g.getpop()) ]
genlist = [ int(g.getgen()) ]
oldsecs = time()
for i in xrange(numsteps):
   g.step()
   poplist.append( int(g.getpop()) )
   genlist.append( int(g.getgen()) )
   newsecs = time()
   if newsecs - oldsecs >= 1.0:     # show pattern every second
      oldsecs = newsecs
      fit_if_not_visible()
      g.update()
      g.show("Step %i of %i" % (i+1, numsteps))

fit_if_not_visible()

# save some info before we switch layers
stepsize = "%i^%i" % (g.getbase(), g.getstep())
pattname = g.getname()

# create population plot in separate layer
g.setoption("stacklayers", 0)
g.setoption("tilelayers", 0)
g.setoption("showlayerbar", 1)
if poplayer == -1:
   poplayer = g.addlayer()
else:
   g.setlayer(poplayer)
g.new(layername)

# use same rule but without any suffix (we don't want a bounded grid)
g.setrule(g.getrule().split(":")[0])

deadr, deadg, deadb = g.getcolor("deadcells")
if (deadr + deadg + deadb) / 3 > 128:
   # use black if light background
   g.setcolors([1,0,0,0])
else:
   # use white if dark background
   g.setcolors([1,255,255,255])

minpop = min(poplist)
maxpop = max(poplist)
if minpop == maxpop:
   # avoid division by zero
   minpop -= 1
popscale = float(maxpop - minpop) / float(ylen)

mingen = min(genlist)
maxgen = max(genlist)
genscale = float(maxgen - mingen) / float(xlen)

# draw axes with origin at 0,0
draw_line(0, 0, xlen, 0)
draw_line(0, 0, 0, -ylen)

# add annotation using mono-spaced ASCII font
t = make_text(pattname.upper(), "mono")
bbox = getminbox(t)
t.put((xlen - bbox.wd) / 2, -ylen - 10 - bbox.ht)

t = make_text("POPULATION", "mono")
bbox = getminbox(t)
t.put(-10 - bbox.ht, -(ylen - bbox.wd) / 2, rccw)

t = make_text(str(minpop), "mono")
bbox = getminbox(t)
t.put(-bbox.wd - 10, -bbox.ht / 2)

t = make_text(str(maxpop), "mono")
bbox = getminbox(t)
t.put(-bbox.wd - 10, -ylen - bbox.ht / 2)

t = make_text("GENERATION (step=%s)" % stepsize, "mono")
bbox = getminbox(t)
t.put((xlen - bbox.wd) / 2, 10)

t = make_text(str(mingen), "mono")
bbox = getminbox(t)
t.put(-bbox.wd / 2, 10)

t = make_text(str(maxgen), "mono")
bbox = getminbox(t)
t.put(xlen - bbox.wd / 2, 10)

# display result at scale 1:1
g.fit()
g.setmag(0)
g.show("")

# plot the data (do last because it could take a while if numsteps is huge)
x = int(float(genlist[0] - mingen) / genscale)
y = int(float(poplist[0] - minpop) / popscale)
oldsecs = time()
for i in xrange(numsteps):
   newx = int(float(genlist[i+1] - mingen) / genscale)
   newy = int(float(poplist[i+1] - minpop) / popscale)
   draw_line(x, -y, newx, -newy)
   x = newx
   y = newy
   newsecs = time()
   if newsecs - oldsecs >= 1.0:     # update plot every second
      oldsecs = newsecs
      g.update()