#!/usr/bin/env python
#Guruprasad Ananda

import sys, os, zipfile, tempfile

QUAL_UPPER_BOUND = 41
QUAL_LOWER_BOUND = 1

def stop_err( msg ):
    sys.stderr.write( "%s\n" % msg )
    sys.exit()
 
def unzip( filename ):
    zip_file = zipfile.ZipFile( filename, 'r' )
    tmpfilename = tempfile.NamedTemporaryFile().name
    for name in zip_file.namelist():
        file( tmpfilename, 'a' ).write( zip_file.read( name ) )
    zip_file.close()
    return tmpfilename
   
def __main__():

    infile_score_name = sys.argv[1].strip()
    fout = open(sys.argv[2].strip(),'r+w')

    infile_is_zipped = False
    if zipfile.is_zipfile( infile_score_name ):
        infile_is_zipped = True
        infile_name = unzip( infile_score_name )
    else:
        infile_name = infile_score_name
    
    readlen = None
    j = 0
    for line in file( infile_name ):
        line = line.strip()
        if not(line) or line.startswith("#") or line.startswith(">"):
            continue
        elems = line.split()
        try:
            for item in elems:
                assert int(item)
            if not(readlen):
                readlen = len(elems)
            if len(elems) != readlen:
                print "Note: Reads in the input dataset are of variable lengths."
            j += 1
        except:
            invalid_lines += 1
        if j > 10:
            break
        
    invalid_lines = 0
    position_dict = {}
    print >>fout, "column\tcount\tmin\tmax\tsum\tmean\tQ1\tmed\tQ3\tIQR\tlW\trW"
    for k,line in enumerate(file( infile_name )):
        line = line.strip()
        if not(line) or line.startswith("#") or line.startswith(">"):
            continue
        elems = line.split()
        if position_dict == {}:
            for pos in range(readlen):
                position_dict[pos] = [0]*QUAL_UPPER_BOUND
        if len(elems) != readlen:
            invalid_lines += 1
            continue
        for ind,item in enumerate(elems):
            try:
                item = int(item)
                position_dict[ind][item]+=1
            except:
                pass
    
    invalid_positions = 0
    for pos in position_dict:
        carr = position_dict[pos] #count array for position pos
        total = sum(carr) #number of bases found in this column.
        med_elem = int(round(total/2.0))
        lowest = None   #Lowest quality score value found in this column.
        highest = None  #Highest quality score value found in this column.
        median = None   #Median quality score value found in this column.
        qsum = 0.0      #Sum of quality score values for this column.
        q1 = None       #1st quartile quality score.
        q3 = None       #3rd quartile quality score.
        q1_elem = int(round((total+1)/4.0))
        q3_elem = int(round((total+1)*3/4.0))
        
        try:
            for ind,cnt in enumerate(carr):
                qsum += ind*cnt
                
                if cnt!=0:
                    highest = ind
                
                if lowest==None and cnt!=0:  #first non-zero count
                    lowest = ind
                
                if q1==None:
                    if sum(carr[:ind+1]) >= q1_elem:
                        q1 = ind
                           
                if median==None:
                    if sum(carr[:ind+1]) < med_elem:
                        continue
                    median = ind
                    if total%2 == 0: #even number of elements
                        median2 = median
                        if sum(carr[:ind+1]) < med_elem+1:
                            for ind2,elem in enumerate(carr[ind+1:]):
                                if elem != 0:
                                    median2 = ind+ind2+1
                                    break
                        median = (median + median2)/2.0
    
                
                if q3==None:
                    if sum(carr[:ind+1]) >= q3_elem:
                        q3 = ind
                 
                
            mean = qsum/total    #Mean quality score value for this column.
            iqr = q3-q1
            left_whisker = max(q1 - 1.5*iqr,lowest)
            right_whisker = min(q3 + 1.5*iqr,highest)
            
            print >>fout,"%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s\t%s" %(pos+1,total,lowest,highest,qsum,mean,q1,median,q3,iqr,left_whisker,right_whisker)
        except:
            invalid_positions += 1
            nullvals = ['NA']*11
            print >>fout,"%s\t%s" %(pos+1,'\t'.join(nullvals))

    if invalid_lines:
        print "Skipped %d reads as invalid." %invalid_lines
    if invalid_positions:
        print "Skipped stats computation for %d read postions." %invalid_positions
        
if __name__=="__main__":
    __main__()