"""
visual_culture.readers

"""

import re
import git_info.git as git


Readers = {}


# class decorator

def reader(mime_pattern):
    def decorator(cls):
        name = cls.__name__
        print('Decorating [%s] with [%s]'%(name, mime_pattern))
        Readers[mime_pattern] = cls
        
        def get_blob_data(self, blob_info):
            repo = git.GitCollection()[blob_info['repo_name']]
            return repo[blob_info['blob_hex']].data
        
        setattr(cls, 'get_blob_data', get_blob_data)
        return cls
    return decorator


class MimeNotSupported(Exception):
    def __init__(self, mime):
        self.mime = mime
    def __str__(self):
        return '[%s] not supported (yet)'%(self.mime)

class Reader(object):
    """
    Factory reader.
    """
    def __init__(self):
        #self.service = service_root
        self.readers = {}
        self.tasks = []
    
    def get_reader(self, mime):
        reader = None
        for r in self.readers.keys():
            if re.match(r, mime) != None:
                return  self.readers[r]
                
        for R in Readers.keys():
            cr = re.compile(R)
            if re.match(cr, mime) != None:
                self.readers[cr] = Readers[R]()
                return  self.readers[cr]
        
        print('MimeNotSupported %s'%(mime,))
        raise MimeNotSupported(mime)
        
    def read_blob(self, blob_info, options={}):
        reader = self.get_reader(blob_info['mime'])
        result = reader.read_blob(blob_info, options)
        return result
        #return HttpResponse(result['data'], mimetype=result['mime'])
        
        

from config import *