#! /usr/bin/python3

import random
import sys
import os
import atexit

# suppress pygame self-advertisement
# https://stackoverflow.com/questions/51464455/why-when-import-pygame-it-prints-the-version-and-welcome-message-how-delete-it#51470016
with open(os.devnull, 'w') as f:
    # disable stdout
    oldstdout = sys.stdout
    sys.stdout = f
    import pygame
    # enable stdout
    sys.stdout = oldstdout
import cgi
import cgitb
import tempfile
import subprocess
import time
import email

cgitb.enable()

# template definition
template_file = 'template.jpg'
# pixel coordinates of the dot matrix corners
top_left = [1011.0, 1011.0]
bottom_left = [1009.0, 1097.0]
top_right = [2175.0, 1048.0]
bottom_right = [2174.0, 1129.0]
# dot matrix
resolution = [125.0, 7.0]
radius = 5.5

# convert from dot coordinates to image pixel coordinates, using
# two-dimensional linear interpolation
def dot2pixel(dot):
    assert (dot[0] >= 0 and dot[0] < resolution[0])
    assert (dot[1] >= 0 and dot[1] < resolution[1])

    # scale incoming dots to floating point interval [0,1]
    rightness = dot[0]/(resolution[0]-1.0)
    leftness = 1.0-rightness
    bottomness = dot[1]/(resolution[1]-1.0)
    topness = 1.0-bottomness

    # print '%g-%g %g-%g' % (leftness,rightness, topness,bottomness)

    pixx = (top_left[0] * leftness * topness + 
            top_right[0] * rightness * topness +
            bottom_left[0] * leftness * bottomness + 
            bottom_right[0] * rightness * bottomness)
    
    pixy = (top_left[1] * leftness * topness + 
            top_right[1] * rightness * topness +
            bottom_left[1] * leftness * bottomness + 
            bottom_right[1] * rightness * bottomness)

    return [pixx, pixy]


# draw an approximate circle near the pixel coordinates of the given dot
def splotch(sfc, dot, col):
    pixcenter = dot2pixel(dot)
    # add a little bit of offset noise
    amplitude=0.9
    pixx = pixcenter[0] + (random.random()-0.5)*amplitude
    pixy = pixcenter[1] + (random.random()-0.5)*amplitude
    # add a little bit of radius noise
    amplitude = 0.8
    myradius = radius + (random.random()-0.5)*amplitude
    r = pygame.Rect (int(pixx-myradius), int(pixy-myradius), int(myradius*2), int(myradius*2))
    # add a little bit of color noise
    col2 = col.correct_gamma (2.0 + 3*(random.random()-0.5))
    pygame.draw.ellipse (sfc, col2, r)
    # add a little highlight
    for i in range(0,4):
        myradius = (myradius + (random.random()-0.5)*amplitude) * 0.9
        r = pygame.Rect (int(pixx-myradius/2), int(pixy-myradius/2), int(myradius), int(myradius))
        col = pygame.Color((255+col.r)/2,
                           (255+col.g)/2,
                           (255+col.b)/2)
        pygame.draw.ellipse (sfc, col, r)

# blank the given dot by an oversize black circle
def unsplotch(sfc, dot, col):
    pixcenter = dot2pixel(dot)
    margin=4
    r = pygame.Rect (int(pixcenter[0]-radius-margin),
                     int(pixcenter[1]-radius-margin),
                     int(radius*2+2*margin), int(radius*2+2*margin))
    pygame.draw.ellipse (sfc, col, r)


# The Font
font = {
    '\'': ["11",
           "11"],

    ' ': ["    "],
    '#': ["  "],     # half-width space

    '.': ["  ",
          "  ",
          "  ",
          "  ",
          "  ",
          "11",
          "11"],

    ',': ["  ",
          "  ",
          "  ",
          "  ",
          " 11",
          " 11",
          "11"],

    '-': ["",
          "",
          "",
          "1111"],

    '!': ["11",
          "11",
          "11",
          "11",
          "  ",
          "11",
          "11"],

    '?': [" 1111",
          "11  11",
          "    11",
          "  111",
          " 11  ",
          "     ",
          " 11  "],

    '1': ["  11",
          " 111",
          "1111",
          "  11",
          "  11",
          "  11",
          "  11"],

    '2': [" 1111",
          "11  11",
          "    11",
          "  111 ",
          " 11  ",
          "11  ",
          "111111"],

    '3': [" 1111",
          "11  11",
          "    11",
          "  111 ",
          "    11",
          "11  11",
          " 1111"],

    '4': ["  111",
          " 1111",
          "11 11",
          "111111",
          "   11",     
          "   11",
          "   11"],

    '5': ["111111",
          "11 ",
          "11",
          "11111 ",
          "    11",
          "11  11",
          " 1111"],

    '6': [" 1111",
          "11  11",
          "11",
          "11111 ",
          "11  11",
          "11  11",
          " 1111"],

    '7': ["111111",
          "    11",
          "   11",
          "  11",
          " 11",
          "11",
          "11"],

    '8': [" 1111",
          "11  11",
          "11  11",
          " 1111 ",
          "11  11",
          "11  11",
          " 1111"],

    '9': [" 1111",
          "11  11",
          "11  11",
          " 11111",
          "    11",
          "11  11",
          " 1111"],

    '0': [" 1111",
          "11  11",
          "11  11",
          "11  11",
          "11  11",
          "11  11",
          " 1111"],

    'A': ["  11  ",
          " 1111 ",
          "11  11",
          "11  11",
          "111111",
          "11  11",
          "11  11"],

    'B': ["11111",
          "11  11",
          "11  11",
          "11111 ",
          "11  11",
          "11  11",
          "11111"],

    'C': [" 1111 ",
          "11  11",
          "11    ",
          "11    ",
          "11    ",
          "11  11",
          " 1111 "],

    'D': ["11111",
          "11  11",
          "11  11",
          "11  11",
          "11  11",
          "11  11",
          "11111"],

    'E': ["111111",
          "11   ",
          "11   ",
          "11111 ",
          "11   ",
          "11   ",
          "111111"],

    'F': ["111111",
          "11    ",
          "11    ",
          "11111 ",
          "11    ",
          "11    ",
          "11    "],

    'G': [" 1111 ",
          "11  11",
          "11    ",
          "11    ",
          "11 111",
          "11  11",
          " 1111 "],

    'H': ["11  11",
          "11  11",
          "11  11",
          "111111",
          "11  11",
          "11  11",
          "11  11"],

    'I': ["1111",
          " 11 ",
          " 11 ",
          " 11 ",
          " 11 ",
          " 11 ",
          "1111"],

    'J': ["  1111",
          "   11 ",
          "   11 ",
          "   11 ",
          "   11 ",
          "11 11 ",
          " 111"],

    'K': ["11  11",
          "11 11",
          "1111",
          "111 ",
          "1111",
          "11 11",
          "11  11"],

    'L': ["11",
          "11",
          "11",
          "11",
          "11",
          "11",
          "111111"],

    'M': ["11   11",
          "111 111",
          "1111111",
          "11 1 11",
          "11   11",
          "11   11",
          "11   11"],

    'N': ["11   11",
          "111  11",
          "1111 11",
          "11 1111",
          "11  111",
          "11   11",
          "11   11"],

    'O': [" 11111 ",
          "11   11",
          "11   11",
          "11   11",
          "11   11",
          "11   11",
          " 11111 "],

    'P': ["11111 ",
          "11  11",
          "11  11",
          "11111 ",
          "11    ",
          "11",
          "11"],

    'Q': [" 11111 ",
          "11   11",
          "11   11",
          "11   11",
          "11  111",
          "11   11",
          " 1111 11"],


    'R': ["11111 ",
          "11  11",
          "11  11",
          "11111 ",
          "1111 ",
          "11 11",
          "11  11"],

    'S': [" 1111",
          "11  11",
          "11",
          " 1111",
          "    11",
          "11  11",
          " 1111"],

    'T': ["111111",
          "  11  ",
          "  11  ",
          "  11  ",
          "  11  ",
          "  11  ",
          "  11  "],

    'U': ["11   11",
          "11   11",
          "11   11",
          "11   11",
          "11   11",
          "11   11",
          " 11111"],

    'V': ["11  11",
          "11  11",
          "11  11",
          "11  11",
          "11  11",
          " 1111",
          "  11 "],

    'W': ["11   11",
          "11   11",
          "11   11",
          "11 1 11",
          "1111111",
          "111 111",
          "11   11"],

    'X': ["11  11",
          "11  11",
          " 1111 ",
          "  11  ",
          " 1111 ",
          "11  11",
          "11  11"],

    'Y': ["11  11",
          "11  11",
          " 1111 ",
          "  11  ",
          "  11  ",
          "  11  ",
          "  11  "],

    'Z': ["111111",
          "    11",
          "   11",
          "  11  ",
          " 11   ",
          "11   ",
          "111111"],

    }


# look up the width of the first line of the glyph
def glyphwidth(char): 
    try:
        return max(len(x) for x in font[char])
    except:
        return 0

def unsplotch_all(sfc):
    for y in range(0, int(resolution[1])):
        for x in range(0, int(resolution[0])):
            unsplotch(sfc, [x, y], pygame.Color(16,17,9)) # clear spot, official background brown


# layout and draw given text on surface          
def splotch_string(sfc, text, faulty):
    # pass 1: compute total width
    width=sum(glyphwidth(x) for x in text) + len(text) - 1
    assert (width <= resolution[0])
    # pass 2: draw them, character by character
    startx = (resolution[0]/2)-(width/2)
    for char in text:
        charwidth = glyphwidth(char)
        # draw each row
        for y in range(0, int(resolution[1])):
            # draw each column
            for x in range(0, charwidth):
                try:
                    pixel = font[char][y][x]
                    if (faulty and random.random()<0.01):
                        pixel=' ' # burned out
                    elif (faulty and random.random()<0.005):
                        pixel='#' # stuck on
                    if (not pixel.isspace()):
                        splotch(sfc, [startx+x, y], pygame.Color(255,192,9)) # the official orange
                except:
                    pass
        startx += charwidth + 1 # char just drawn + space

form = cgi.FieldStorage()
scale = int(form.getfirst("scale","25")) / 100.0
assert (scale > 0.0 and scale <= 1.0)
koan = form.getfirst("koan","")
assert (len(koan) > 0 and len(koan) <= 400)

faulty = (form.getfirst("faulty","off") == "on")

sfc = pygame.image.load(template_file)
size = (int(sfc.get_width()*scale), int(sfc.get_height()*scale))

tmpdir=tempfile.mkdtemp()

atexit.register(lambda: subprocess.call(["rm","-rf",tmpdir]))


index=0
for line in koan.split('\n'):
    unsplotch_all(sfc)
    try:
        splotch_string(sfc,line.upper(),faulty)
    except:
        print ('Content-Type: text/plain\n')
        print ('Please break up long line %s before trying again.' % line)
        exit(0)

    disp_surf = pygame.transform.smoothscale(sfc, size)
    index = index + 1
    fname='%s/%03d.jpg' % (tmpdir,index)
    pygame.image.save(disp_surf, fname)
#    sys.stderr.write('wrote inglis koan %s frame %s: %s\n' % (line, fname, os.stat(fname)))

anifname = "%s/animation.gif" % tmpdir
rc = subprocess.call(["convert","-delay","150","-loop","0","-comment","http://web.elastic.org/~fche/inglis/","%s/*.jpg" % tmpdir,anifname])
# sys.stderr.write('wrote inglis animation %s: %s\n' % (anifname, os.stat(anifname)))
#assert (rc == 0)

sys.stdout.buffer.write (b'Content-Type: image/gif\n')
sys.stdout.buffer.write (b'Cache-Control: public, max-age=31536000\n')
# print ('Last-Modified: '+email.Utils.formatdate())
sys.stdout.buffer.write (b'\n')
f = open(anifname, 'rb')
sys.stdout.buffer.write(f.read())


# test with
# env QUERY_STRING=koan=foo inglis.py