terom@0: #!/usr/bin/python2.5
terom@3: import werkzeug
terom@3: from werkzeug.exceptions import HTTPException
terom@3: import wsgiref.handlers
terom@0: 
terom@1: from PIL import Image, ImageDraw, ImageFont, ImageEnhance
terom@0: from cStringIO import StringIO
terom@0: import random
terom@0: 
terom@0: 
terom@3: class Defaults :
terom@3:     # settings
terom@3:     text = [
terom@3:         "aalto",
terom@3:         "unive",
terom@3:         "rsity"
terom@3:     ]
terom@0: 
terom@3:     chars = [ '"', '!', '?' ]
terom@0: 
terom@3:     line_colors = [
terom@3:         "#0469af",
terom@3:         "#fbc614",
terom@3:         "#e1313b",
terom@3:     ]
terom@3: 
terom@3:     font_name = 'helvetica'
terom@3:     font_size = 30
terom@3:     
terom@3:     background_color = "#ffffff"
terom@3:     line_spacing = -10
terom@3:     sharpness = 0.6
terom@0: 
terom@0: fonts = {
terom@3:         'dejavu-sans-bold':     "/usr/share/fonts/truetype/ttf-dejavu/DejaVuSans-Bold.ttf",
terom@3:         'helvetica':            "HELR65W.TTF",
terom@3:     }
terom@0: 
terom@3: 
terom@3: # enable debugging
terom@3: debug = True
terom@0: 
terom@0: def randomize (seq) :
terom@0:     """
terom@0:         Returns the given sequence in random order as a list
terom@0:     """
terom@0:     
terom@0:     # copy
terom@0:     l = list(seq)
terom@0:     
terom@0:     # rearrange
terom@0:     random.shuffle(l)
terom@0: 
terom@0:     return l
terom@0: 
terom@0: def build_data (text, chars, line_colors) :
terom@0:     """
terom@0:         Returns a matrix of (text, color) tuples representing the data to render
terom@0: 
terom@0:         [ [ (str, str) ] ]
terom@0: 
terom@0:             text        - list of lines
terom@0:             chars       - list of random chars to interpse
terom@0:             line_colors - list of colors to draw the chars in
terom@0:     """
terom@0: 
terom@0:     data = []
terom@0:     
terom@0:     for line, char, color in zip(text, chars, line_colors) :
terom@0:         # pick position to place char
terom@0:         pos = random.randint(1, len(line) - 1)
terom@0:         
terom@0:         # split into three parts
terom@0:         data.append([
terom@0:                 (line[:pos], "#000000"),
terom@0:                 (char, color),
terom@0:                 (line[pos:], "#000000"),
terom@0:             ])
terom@0:     
terom@0:     return data
terom@0: 
terom@0: def load_font (font_name, font_size) :
terom@0:     """
terom@0:         Load a font by name
terom@0:     """
terom@0:     
terom@0:     # load font
terom@0:     font_path = fonts[font_name]
terom@0:     font = ImageFont.truetype(font_path, font_size)
terom@0:     
terom@0:     return font
terom@0: 
terom@0: def render_img (data, font, background_color="#ffffff", line_spacing=0) :
terom@0:     """
terom@0:         Render the data (as from build_data) as an image, using the given PIL.ImageFont, and return the PIL Image object
terom@0:     """
terom@0: 
terom@0:     img_width = img_height = 0
terom@0: 
terom@0:     img_data = []
terom@0:     
terom@0:     # compute image width/height
terom@0:     for segments in data :
terom@0:         line_width = line_height = 0
terom@0:         
terom@0:         # build a new list of segments with additional info
terom@0:         line_segments = []
terom@0:         
terom@0:         for seg_text, seg_color in segments :
terom@0:             # compute rendered text size
terom@0:             seg_width, seg_height = font.getsize(seg_text)
terom@0:             
terom@0:             # update line_*
terom@0:             line_width += seg_width
terom@0:             line_height = max(line_height, seg_height)
terom@0:             
terom@0:             # build the new segments list
terom@0:             line_segments.append((seg_text, seg_color, seg_width))
terom@0:         
terom@0:         # update img_*
terom@0:         img_width = max(img_width, line_width)
terom@0:         img_height += line_height
terom@0:         img_data.append((line_segments, line_height))
terom@0: 
terom@0:     # calculate height needed for line spacing
terom@0:     img_height += (len(img_data) - 1) * line_spacing
terom@0: 
terom@0:     # create image
terom@0:     img = Image.new("RGB", (img_width, img_height), background_color)
terom@0:     draw = ImageDraw.Draw(img)
terom@0: 
terom@0:     # draw text
terom@0:     img_y = 0
terom@0:     for segments, line_height in img_data :
terom@0:         img_x = 0
terom@0:         
terom@0:         # draw each segment build above, incremeing along img_x
terom@0:         for seg_text, seg_color, seg_width in segments :
terom@0:             draw.text((img_x, img_y), seg_text, font=font, fill=seg_color)
terom@0: 
terom@0:             img_x += seg_width
terom@0:         
terom@0:         img_y += line_height + line_spacing
terom@0:     
terom@0:     return img
terom@0: 
terom@3: def effect_sharpness (img, factor) :
terom@1:     """
terom@3:         Sharpen the image by the given factor
terom@1:     """
terom@1: 
terom@1:     return ImageEnhance.Sharpness(img).enhance(factor)
terom@1: 
terom@0: def build_png (img) :
terom@0:     """
terom@0:         Write the given PIL.Image as a string, returning the raw binary data
terom@0:     """
terom@0: 
terom@0:     # render PNG output
terom@0:     buf = StringIO()
terom@0:     img.save(buf, "png")
terom@0:     data = buf.getvalue()
terom@0: 
terom@0:     return data
terom@0: 
terom@3: def arg_bool (val) :
terom@3:     if val.lower() in ('true', 't', '1', 'yes', 'y') :
terom@3:         return True
terom@3:     elif val.lower() in ('false', 'f', '0', 'no', 'n') :
terom@3:         return False
terom@3:     else :
terom@3:         raise ValueError(val)
terom@3: 
terom@3: def arg_color (val) :
terom@3:     if val.beginswith('#') :
terom@3:         int(val[1:], 16)
terom@3: 
terom@3:         return val
terom@3:     else :
terom@3:         raise ValueError(val)
terom@3: 
terom@3: def handle_request (req) :
terom@3:     # parse args
terom@3:     if 'text' in req.args :
terom@3:         text = req.args.getlist('text', unicode)
terom@3:     else :
terom@3:         text = Defaults.text
terom@3:     
terom@3:     if 'chars' in req.args :
terom@3:         chars = req.args.getlist('chars', unicode)
terom@3:     else :
terom@3:         chars = Defaults.chars
terom@3: 
terom@3:     if 'colors' in req.args :
terom@3:         colors = req.args.getlist('colors', arg_color)
terom@3: 
terom@3:     else :
terom@3:         colors = Defaults.line_colors
terom@3: 
terom@3:     font_name = req.args.get('font', Defaults.font_name)
terom@3:     font_size = req.args.get('font-size', Defaults.font_size, int)
terom@3:     background_color = req.args.get('background-color', Defaults.background_color, arg_color)
terom@3:     line_spacing = req.args.get('line-spacing', Defaults.line_spacing, int)
terom@3:     sharpness = req.args.get('sharpness', Defaults.sharpness, float)
terom@3:     
terom@3:     # put the chars in random order by default
terom@3:     if req.args.get('random_chars', True, arg_bool) :
terom@3:         chars = randomize(chars)
terom@3: 
terom@3:     # load/prep resources
terom@3:     data = build_data(text, chars, colors)
terom@3:     font = load_font(font_name, font_size)
terom@3:     
terom@3:     # render the image
terom@3:     img = render_img(data, font, background_color, line_spacing)
terom@3: 
terom@3:     img = effect_sharpness(img, sharpness)
terom@3: 
terom@3:     png_data = build_png(img)
terom@3:     
terom@3:     # build the response
terom@3:     response = werkzeug.Response(png_data, mimetype='image/png')
terom@3: 
terom@3:     return response
terom@3: 
terom@3: @werkzeug.Request.application
terom@3: def wsgi_application (request) :
terom@0:     """
terom@3:         Our werkzeug WSGI handler
terom@0:     """
terom@0: 
terom@3:     try :
terom@3:         # request -> response
terom@3:         response = handle_request(request)
terom@0: 
terom@3:         return response
terom@3: 
terom@3:     except HTTPException, e :
terom@3:         # return as HTTP response
terom@3:         return e
terom@0: 
terom@0: def main () :
terom@3:     handler = wsgiref.handlers.CGIHandler()
terom@3:     app = wsgi_application
terom@3:     
terom@3:     if debug :
terom@3:         # enable debugging
terom@3:         app = werkzeug.DebuggedApplication(app, evalex=False)
terom@0: 
terom@3:     handler.run(app)
terom@0: 
terom@0: if __name__ == '__main__' :
terom@0:     main()
terom@0: