"""
visual_culture.readers.pdf

"""

from visual_culture.readers import reader

import vc_poppler as poppler
from PIL import Image
import StringIO

import time


@reader(r'application/pdf')
class VC_PDF(object):
    """
    PDF rendering through Cairo
    """
    def __init__(self):
        self.ratio = .3
        
    def get_res(self, options):
        width = 0
        height = 0
        if 'width' in options:
            width = int(options['width'])
        elif 'height' in options:
            height = int(options['height'])    
        if height == 0 and width == 0:
            width = 200
        
        res = 1
        pw = self.page.rect(poppler.page_box.crop_box).width() / 72.0
        ph = self.page.rect(poppler.page_box.crop_box).height() / 72.0
        if width > 0:
            res = width / pw
        else:
            res = height / ph
            
        return res
        
    
    def render_page(self, res):
        print('[VC_PDF][%s] render page @%d'%(time.asctime(), res))
        pr = poppler.PageRenderer()
        pr.set_render_hint(poppler.render_hint.antialiasing, True)
        pr.set_render_hint(poppler.render_hint.text_antialiasing, True)
        #raise Exception('About to render page @%d'%res)
        i = pr.render_page(self.page, xres=res, yres=res)
        #print('PDF rendered in %d %d : %s %d'%(i.width(), i.height(), i.format(), i.bytes_per_row()))
        data = i.data()
        #print('Data Type => %s'%type(data))
        im = Image.frombuffer("RGBA", (i.width(), i.height()), data, "raw", "RGBA", 0, 1)
        buf = StringIO.StringIO()
        im.save(buf, 'PNG')
        self.data = buf.getvalue()
        buf.close()
    
    def read_blob(self, blob_info, options):
        #print('[VC_PDF][%s] read blob (%s)'%(time.asctime(), blob_info['blob_url']))
        blob_data = self.get_blob_data(blob_info)
        loader = poppler.Loader()
        self.doc = loader.from_data(blob_data)
        self.page = self.doc.page(0)
        res = self.get_res(options)
        self.render_page(res)
        
        return {'data':self.data, 'mime': 'image/png'}