#v 1.0
import sys, os, time, re
import urllib, urllib2 
from optparse import OptionParser
from HTMLParser import HTMLParser
from xml.dom.minidom import parseString

#id mapping
def getPDBIdandChain(uniprotID):
    #data from http://www.bioinf.org.uk/pdbsws/
    dirPath = os.path.dirname(sys.argv[0])
    fileName ='pdb_uniprot_chain_map.lst.2'
    if len(dirPath) != 0:
        fileName = dirPath + "/pdb_uniprot_chain_map.lst.2"
    fileName = fileName.replace('\\', '/')
    f = open (fileName, 'r')
    pdbId = ''
    chain = ''
    while(1):
        line = f.readline()
        if not line:
            break
        line = line.rstrip('\n')
        columns = line.split()
        if len(columns) != 3:
            continue
        if columns[2] == uniprotID:
            pdbId = columns[0]
            chain = columns[1]
    f.close()
    return pdbId, chain

# Define a function for the thread

class NoRedirectHandler(urllib2.HTTPRedirectHandler):
    def http_error_302(self, req, fp, code, msg, headers):
        infourl = urllib.addinfourl(fp, headers, req.get_full_url())
        infourl.status = code
        infourl.code = code
        return infourl
    http_error_300 = http_error_302
    http_error_301 = http_error_302
    http_error_303 = http_error_302
    http_error_307 = http_error_302

def prepare_optparser():
    """Prepare optparser object. New options will be added in this
    function first.
    """
    usage = "usage: %prog <-p STRING -c STRING -m STRING> [options]"
    description = "SNP2PDBSite."

    optparser = OptionParser(version="%prog v1.0", description=description, usage=usage, add_help_option=False)
    optparser.add_option("-h","--help",action="help",help="Show this help message and exit.")
    
    optparser.add_option("-p","--protId",dest="protId",type="string",
                         help="Enter protein (uniprot) ID.")
    
    optparser.add_option("-c", "--chain", dest="chain",type="string",
                         help="Enter chain.")

    optparser.add_option("-m", "--mut", dest="mutation",type="string",
                         help="Enter mutation.")
                                        
    return optparser

def opt_validate(optparser):
    """Validate options from a OptParser object.

    Return: Validated options object.
    """
    (options,args) = optparser.parse_args()
            
    if not (options.protId and options.chain and options.mutation):
        optparser.print_help()
        sys.exit(1)
    if '"' in options.protId:
        options.protId = options.protId.replace('"','')
        
    if '"' in options.mutation:
        options.mutation = options.mutation.replace('"','')
       
    id, chain = getPDBIdandChain(options.protId)
    if not (id and chain):
        sys.exit(1)
    
    options.chain = chain
    options.protId = id
    mutList = list(options.mutation)
    mutList[0] = chain
    options.mutation = "".join(mutList)
 
    return options

class Snp2pdbsite:
    def __init__(self, options):
        self.protId = options.protId
        if not options.chain:
            options.chain = "" 
        self.chain = options.chain
        if not options.mutation:
            options.mutation = "" 
        self.mutation = options.mutation
        self.url = 'http://www-bionet.sscc.ru/psd2/rest.php?tool=snp2pdbsite'

    def sendQuery(self):
        opener = urllib2.build_opener(NoRedirectHandler())
        urllib2.install_opener(opener)
        # do POST
                                          
        params = urllib.urlencode({'pdb': self.protId, 'chain': self.chain, 'mut': self.mutation})
        req = urllib2.Request(self.url,  params)

        rsp = urllib2.urlopen(req) 

        content = rsp.read()
        res = content.find('qid=')
        content = content[res+5:]
        res = content.find('"')
        content = content[:res]
        self.url = "http://www-bionet.sscc.ru/psd2/rest.php?tool=snp2pdbsite&q=%s" %content
        self.getResult()      

    def getResult(self):
        opener = urllib2.build_opener(NoRedirectHandler())
        urllib2.install_opener(opener)
        content = "working"

        while content.find('working') >= 0:
            req = urllib2.Request(self.url)
            rsp = urllib2.urlopen(req) 
            content = rsp.read()
            time.sleep(0.1)
        self.parseOutput(content)
    def parseOutput(self, content):
        if len(content) == 0:
            print "Result is empty"
            sys.exit(1)
            
        xmldoc = parseString(content)
        
        itemlist = xmldoc.getElementsByTagName('aa')
        if itemlist.length <= 0:
            print "Result is empty"
            sys.exit(1)
        for item in itemlist:
            print "PDB_SITE" + ':' + item.getAttribute("pos") + item.getAttribute("aa") + ';'
def main():
    opts=opt_validate(prepare_optparser())
    g = Snp2pdbsite(opts)
    g.sendQuery()
if __name__ == "__main__":
    main()