#!/usr/bin/env python3

"""
optparse is deprecated in favor of argparse as of Python 2.7. However,
 since 2.7 is not always present on many systems, at this writing,
 it is safer to stick with optparse for now. It should be easy
 to change later, since the syntax is very similar between argparse and optparse.
 from optparse import OptionParser
"""
from optparse import OptionParser

import datetime
import getpass
import os
import re
import shutil
import stat
import subprocess
import sys
import time

'''
bl_fastq_pair.py - Set environment variables for BioLegato Helper Applications

Synopsis: bl_fastq_pair.py --tsv tsvfile [options] 

@modified: April 5, 2019
@author: Brian Fristensky
@contact: Brian.Fristensky@umanitoba.ca  
'''

#blib = os.environ.get("BIRCHPYLIB")
#sys.path.append(blib)

#from birchlib import Birchmod


PROGRAM = "bl_fastq_pair.py : "
USAGE = "\n\tUSAGE: bl_fastq_pair.py --tsv tsvfile [options]"

DEBUG = True
if DEBUG :
    print('bl_fastq_pair: Debugging mode on')

#BM = Birchmod(PROGRAM, USAGE)


# - - - - - - - - - - - - - Utility classes - - - - - - - - - - - - - - - - -
def chmod_ar(filename):
    """
    Make a file world-readable.
    """
    if os.path.exists(filename):
        st = os.stat(filename)
        os.chmod(filename, st.st_mode | stat.S_IREAD \
        | stat.S_IRGRP | stat.S_IROTH)

		
def chmod_arx(filename):
    """
    Make a file or directory world-readable and world-executable/searchable.
    """
    if os.path.exists(filename):
        st = os.stat(filename)
        os.chmod(filename, st.st_mode | stat.S_IEXEC | stat.S_IREAD \
            | stat.S_IXGRP | stat.S_IRGRP | stat.S_IXOTH \
            | stat.S_IROTH)

def LocalHostname():
    """
    Return the name of the local machine. Tries a number of methods
    to get a name other than 'localhost' or a null result.
    """
    import socket
    import platform

    def CheckName(name) :
        if name == None or name.startswith("localhost") or name == "" :
            OKAY = False
        else :
            OKAY = True
        return OKAY

    name = os.getenv('HOSTNAME') 

    if not CheckName(name) :
        name = platform.uname()[1]

    if not CheckName(name) :
        if socket.gethostname().find('.')>=0:
            name=socket.gethostname()
        else:
            name=socket.gethostbyaddr(socket.gethostname())[0]

    return name


def SendEmail(From,To,Subject,Text) :
    """
        Very simple email method adapted from:
        http://stackoverflow.com/questions/882712/sending-html-email-using-python
        There are more elaborate examples on this site for sending
        HTML messages and attachments.
    """
    import smtplib
    from email.mime.multipart import MIMEMultipart
    from email.mime.text import MIMEText

    Host = 'localhost'

    msg = MIMEMultipart('alternative')
    msg['Subject'] = Subject
    Html = """\
        <html>
          <head></head>
          <body>
            <p>
            %s
            </p>
          </body>
        </html>
        """ %(Text)
    part1 = MIMEText(Text, 'plain')
    part2 = MIMEText(Html, 'html')
    msg.attach(part1)
    msg.attach(part2)

    try:
       server = smtplib.SMTP(Host)
       server.sendmail(From, To, msg.as_string())
       server.quit()         

       print("Successfully sent email")
    except :
       print("Error: unable to send email")


# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
class Parameters:
    """
      	Wrapper class for command line parameters
      	"""
    def __init__(self):
        """
     	  Initializes arguments:
                TSVFILE = ""
                HASHSIZE = 100000
                BUCKETS = False
                OUTDIR = ""
                EMAIL = ""

     	  Then calls read_args() to fill in their values from command line
          """
        self.TSVFILE = "."
        self.HASHSIZE = 100000
        self.BUCKETS = False
        self.OUTDIR = "."
        self.EMAIL = ""          
        self.read_args()


        if DEBUG :
            print('------------ Parameters from command line ------')
            print('    TSVFILE: ' + self.TSVFILE)
            print('    HASHSIZE: ' + str(self.HASHSIZE))
            print('    BUCKETS: ' + str(self.BUCKETS))
            print('    OUTDIR: ' + self.OUTDIR)
            print('    EMAIL: ' + self.EMAIL)
            print()  

    def read_args(self):
        """
        	Read command line arguments into a Parameter object
    	"""
            
        parser = OptionParser()
        parser.add_option("--tsvfile", dest="tsvfile", action="store", default="",
                          help="list of paired/unpaired read files")
        parser.add_option("--hashsize", dest="hashsize", action="store", default=100000,
                          help="trim N bases in addition to adapter removal")
        parser.add_option("--buckets", dest="buckets", action="store_true", default=False,
                          help="Write number of sequences per bucket to output")
        parser.add_option("--outdir", dest="outdir", action="store", default=".",
                          help="output directory")
        parser.add_option("--email", dest="email", action="store", default="",
                          help="send email upon completion")

        (options, args) = parser.parse_args() 
        self.TSVFILE = options.tsvfile
        self.HASHSIZE = options.hashsize
        self.BUCKETS = options.buckets
        self.OUTDIR = options.outdir
        self.EMAIL = options.email

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
class TSVFiles :
    """
    Methods for reading lists of paired read TSV files, and for
    writing lists to output.
    """
    def __init__(self):
        """
     	  Initializes arguments:
                READPAIRS = []

          """
        self.READPAIRS = []            

    def ReadTSVfile(self,FN) :
        """
        TSV file containing names of paired-end and/or single end read files.
        Paired-end files are on lines such as

        leftreadfile.fq.gz<TAB>rightreadfile.fq.gz

        Single-end files have a each file on a separate line

        reads1.fq.gz
        reads2.fq.gz
        reads3.fq.gz
        """
        TAB = '\t'
        F = open(FN,"r")
        for line in F.readlines() :
            line = line.strip()
            if len(line) > 0 and not line.startswith('#') :
                # get rid of double quotes that enclose fields when some programs write
                # output, and then split by TABs.
                tokens = line.replace('"','').split(TAB)

                # ignore blank fields. Add either single or pair of filenames
                # to list. Only process names from first two fields on a line
                # and ignore other fields. 
                if len(tokens) > 0 :
                    r1 = tokens[0].strip()
                    if len(r1) > 0 :
                        fnames = [r1]
                    else :
                        fnames = []
                    if len(tokens) > 1 :
                        r2 = tokens[1].strip()
                        if len(r2) > 0 :
                            fnames.append(r2)
                    if len(fnames) > 0 :
                        self.READPAIRS.append(fnames)
        if DEBUG :
            print(str(self.READPAIRS))
        F.close()

# - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
def RunFastq_Pair(P,PR,LOGFILE) :

    def MoveOutfiles(FN,OUTDIR) :
        PairedFile = FN + '.paired.fq'
        Dest = os.path.join(OUTDIR,PairedFile)
        shutil.move(PairedFile,Dest)
        SingleFile = FN + '.single.fq'
        Dest = os.path.join(OUTDIR,SingleFile)
        shutil.move(SingleFile,Dest)

    # Only process pairs of files
    if len(PR) == 2 :
        COMMAND=["fastq_pair"]
        if P.BUCKETS :
             COMMAND.append("-p")
        COMMAND.extend(["-t", str(P.HASHSIZE)])
        COMMAND.extend([PR[0],PR[1]])
        # Run the command - - - - - - - - - - - - - - - - -
        LOGFILE.write('======== fastq_pair ==========' + '\n')
        LOGFILE.write(str(COMMAND) + '\n')
        StartTime = datetime.datetime.now()
        LOGFILE.write('Start time: ' + str(StartTime) + '\n')
        LOGFILE.write('\n')
        LOGFILE.flush()
        p = subprocess.Popen(COMMAND,stdout=LOGFILE, stderr=LOGFILE)
        p.wait()
        FinishTime = datetime.datetime.now()
        LOGFILE.write('\n')
        LOGFILE.write('Finish time: ' + str(FinishTime) + '\n')
        ElapsedTime = FinishTime - StartTime
        LOGFILE.write('Elapsed time: ' + str(ElapsedTime) + '\n')

        # Move output files to OUTDIR
        MoveOutfiles(PR[0],P.OUTDIR)
        MoveOutfiles(PR[1],P.OUTDIR)

    else :
        LOGFILE.write('Ignoring single file ' + PR[0] + '\n')        

#======================== MAIN PROCEDURE ==========================
def main():
    """
        Called when not in documentation mode.
        """
	
    # Read parameters from command line
    P = Parameters()

    TF = TSVFiles()
    if not P.TSVFILE == "" :
        TF.ReadTSVfile(P.TSVFILE)
        OKAY = True
    else :
        OKAY = False
    
    if not os.path.exists(P.OUTDIR) :
        os.mkdir(P.OUTDIR)                     
    LOGFN = os.path.join(P.OUTDIR,'bl_fastq_pair.log')
    # First create the file, then re-open it so that we can append to it.
    # We first create with 'w' just to make sure that we're creating a fresh copy,
    # rather than appending to an existing copy from a previous run.
    LOGFILE = open(LOGFN,'w')
    LOGFILE.close()
    LOGFILE = open(LOGFN,'a')
    LOGFILE.write('\n')

    # Run fastq_pair
    if OKAY :
        for PR in TF.READPAIRS :
            RunFastq_Pair(P,PR,LOGFILE)
          
    LOGFILE.close()

    # Notify user when job is done, if email address was
    # supplied using --email
    if P.EMAIL != "" :
        Sender = getpass.getuser() + '@' + LocalHostname()
        Subject = 'bl_fastq_pair.py completed'
        Message = 'bl_fastq_pair.py: Completed<br>'
        LOGFILE = open(os.path.join('bl_fastq_pair.log'),'r')
        for line in LOGFILE.readlines() :
            Message = Message + line + '<br>'
        LOGFILE.close()
        SendEmail(Sender,[P.EMAIL],Subject,Message)


if __name__ == "__main__":
    main()
#else:
    #used to generate documentation
#    import doctest
#    doctest.testmod()

#if (BM.documentor() or "-test" in sys.argv):
#    pass
#else:
#    main()
