#################################
# Copyright (C) 2014 J.F.Dockes
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the
#   Free Software Foundation, Inc.,
#   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
########################################################
## Recoll multifilter communication module and utilities

from __future__ import print_function

import sys
import os
import tempfile
import shutil
import getopt
import rclconfig

my_config = rclconfig.RclConfig()

############################################
# RclExecM implements the
# communication protocol with the recollindex process. It calls the
# object specific of the document type to actually get the data.
class RclExecM:
    noteof  = 0
    eofnext = 1
    eofnow = 2

    noerror = 0
    subdocerror = 1
    fileerror = 2
    
    def __init__(self):
        try:
            self.myname = os.path.basename(sys.argv[0])
        except:
            self.myname = "???"
        self.mimetype = ""

        if os.environ.get("RECOLL_FILTER_MAXMEMBERKB"):
            self.maxmembersize = \
            int(os.environ.get("RECOLL_FILTER_MAXMEMBERKB"))
        else:
            self.maxmembersize = 50 * 1024
        self.maxmembersize = self.maxmembersize * 1024
        if sys.platform == "win32":
            import msvcrt
            msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)
            msvcrt.setmode(sys.stdin.fileno(), os.O_BINARY)

    def rclog(self, s, doexit = 0, exitvalue = 1):
        print("RCLMFILT: %s: %s" % (self.myname, s), file=sys.stderr)
        if doexit:
            sys.exit(exitvalue)

    # Note: tried replacing this with a multiple replacer according to
    #  http://stackoverflow.com/a/15221068, which was **10 times** slower
    def htmlescape(self, txt):
        # This must stay first (it somehow had managed to skip after
        # the next line, with rather interesting results)
        txt = txt.replace("&", "&")

        txt = txt.replace("<", "&lt;")
        txt = txt.replace(">", "&gt;")
        txt = txt.replace('"', "&quot;")
        return txt

    # Our worker sometimes knows the mime types of the data it sends
    def setmimetype(self, mt):
        self.mimetype = mt

    # Read single parameter from process input: line with param name and size
    # followed by data.
    def readparam(self):
        s = sys.stdin.readline()
        if s == '':
            sys.exit(0)
#           self.rclog(": EOF on input", 1, 0)

        s = s.rstrip("\n")

        if s == "":
            return ("","")
        l = s.split()
        if len(l) != 2:
            self.rclog("bad line: [" + s + "]", 1, 1)

        paramname = l[0].lower()
        paramsize = int(l[1])
        if paramsize > 0:
            paramdata = sys.stdin.read(paramsize)
            if len(paramdata) != paramsize:
                self.rclog("Bad read: wanted %d, got %d" %
                      (paramsize, len(paramdata)), 1,1)
        else:
            paramdata = ""
    
        #self.rclog("paramname [%s] paramsize %d value [%s]" %
        #          (paramname, paramsize, paramdata))
        return (paramname, paramdata)

    # Send answer: document, ipath, possible eof.
    def answer(self, docdata, ipath, iseof = noteof, iserror = noerror):

        if iserror != RclExecM.fileerror and iseof != RclExecM.eofnow:
            if isinstance(docdata, unicode):
                self.rclog("GOT UNICODE for ipath [%s]" % (ipath,))
                docdata = docdata.encode("UTF-8")

            print("Document: %d" % len(docdata))
            sys.stdout.write(docdata)

            if len(ipath):
                print("Ipath: %d" % len(ipath))
                sys.stdout.write(ipath)

            if len(self.mimetype):
                print("Mimetype: %d" % len(self.mimetype))
                sys.stdout.write(self.mimetype)

        # If we're at the end of the contents, say so
        if iseof == RclExecM.eofnow:
            print("Eofnow: 0")
        elif iseof == RclExecM.eofnext:
            print("Eofnext: 0")
        if iserror == RclExecM.subdocerror:
            print("Subdocerror: 0")
        elif iserror == RclExecM.fileerror:
            print("Fileerror: 0")
  
        # End of message
        print()
        sys.stdout.flush()
        #self.rclog("done writing data")

    def processmessage(self, processor, params):

        # We must have a filename entry (even empty). Else exit
        if not params.has_key("filename:"):
            self.rclog("no filename ??", 1, 1)

        # If we're given a file name, open it. 
        if len(params["filename:"]) != 0:
            try:
                if not processor.openfile(params):
                    self.answer("", "", iserror = RclExecM.fileerror)
                    return
            except Exception, err:
                self.rclog("processmessage: openfile raised: [%s]" % err)
                self.answer("", "", iserror = RclExecM.fileerror)
                return

        # If we have an ipath, that's what we look for, else ask for next entry
        ipath = ""
        eof = True
        self.mimetype = ""
        try:
            if params.has_key("ipath:") and len(params["ipath:"]):
                ok, data, ipath, eof = processor.getipath(params)
            else:
                ok, data, ipath, eof = processor.getnext(params)
        except Exception, err:
            self.answer("", "", eof, RclExecM.fileerror)
            return

        #self.rclog("processmessage: ok %s eof %s ipath %s"%(ok, eof, ipath))
        if ok:
            self.answer(data, ipath, eof)
        else:
            self.answer("", "", eof, RclExecM.subdocerror)

    # Loop on messages from our master
    def mainloop(self, processor):
        while 1:
            #self.rclog("waiting for command")

            params = dict()

            # Read at most 10 parameters (normally 1 or 2), stop at empty line
            # End of message is signalled by empty paramname
            for i in range(10):
                paramname, paramdata = self.readparam()
                if paramname == "":
                    break
                params[paramname] = paramdata

            # Got message, act on it
            self.processmessage(processor, params)


# Helper routine to test for program accessibility
def which(program):
    def is_exe(fpath):
        return os.path.exists(fpath) and os.access(fpath, os.X_OK)
    def ext_candidates(fpath):
        yield fpath
        for ext in os.environ.get("PATHEXT", "").split(os.pathsep):
            yield fpath + ext

    def path_candidates():
        yield os.path.dirname(sys.argv[0])
        rclpath = my_config.getConfParam("recollhelperpath")
        if rclpath:
            for path in rclpath.split(os.pathsep):
                yield path
        for path in os.environ["PATH"].split(os.pathsep):
            yield path
            
    fpath, fname = os.path.split(program)
    if fpath:
        if is_exe(program):
            return program
    else:
        for path in path_candidates():
            exe_file = os.path.join(path, program)
            for candidate in ext_candidates(exe_file):
                if is_exe(candidate):
                    return candidate
    return None

# Temp dir helper
class SafeTmpDir:
    def __init__(self, em):
        self.em = em
        self.toptmp = ""
        self.tmpdir = ""

    def __del__(self):
        try:
            if self.toptmp:
                shutil.rmtree(self.tmpdir, True)
                os.rmdir(self.toptmp)
        except Exception as err:
            self.em.rclog("delete dir failed for " + self.toptmp)

    def getpath(self):
        if not self.tmpdir:
            envrcltmp = os.getenv('RECOLL_TMPDIR')
            if envrcltmp:
                self.toptmp = tempfile.mkdtemp(prefix='rcltmp', dir=envrcltmp)
            else:
                self.toptmp = tempfile.mkdtemp(prefix='rcltmp')

            self.tmpdir = os.path.join(self.toptmp, 'rclsofftmp')
            os.makedirs(self.tmpdir)

        return self.tmpdir
   

# Common main routine for all python execm filters: either run the
# normal protocol engine or a local loop to test without recollindex
def main(proto, extract):
    if len(sys.argv) == 1:
        proto.mainloop(extract)
        # mainloop does not return. Just in case
        sys.exit(1)


    # Not running the main loop: either acting as single filter (when called
    # from other filter for example), or debugging
    def usage():
        print("Usage: rclexecm.py [-d] [-s] [-i ipath] [filename]",
              file=sys.stderr)
        sys.exit(1)
        
    actAsSingle = False
    debugDumpData = False
    ipath = ""

    args = sys.argv[1:]
    opts, args = getopt.getopt(args, "hdsi:")
    for opt, arg in opts:
        if opt in ['-h']:
            usage()
        elif opt in ['-s']:
            actAsSingle = True
        elif opt in ['-i']:
            ipath = arg
        elif opt in ['-d']:
            debugDumpData = True
        else:
            print("unknown option %s\n"%opt, file=sys.stderr)
            usage()

    if len(args) != 1:
        usage()
        
    def mimetype_with_file(f):
        cmd = 'file -i "' + f + '"'
        fileout = os.popen(cmd).read()
        lst = fileout.split(':')
        mimetype = lst[len(lst)-1].strip()
        lst = mimetype.split(';')
        return lst[0].strip()

    def mimetype_with_xdg(f):
        cmd = 'xdg-mime query filetype "' + f + '"'
        return os.popen(cmd).read().strip()

    def debprint(s):
        if not actAsSingle:
            print(s)
            
    params = {'filename:': args[0]}
    # Some filters (e.g. rclaudio) need/get a MIME type from the indexer
    mimetype = mimetype_with_xdg(args[0])
    params['mimetype:'] = mimetype

    if not extract.openfile(params):
        print("Open error", file=sys.stderr)
        sys.exit(1)

    if ipath != "" or actAsSingle:
        params['ipath:'] = ipath
        ok, data, ipath, eof = extract.getipath(params)
        if ok:
            debprint("== Found entry for ipath %s (mimetype [%s]):" % \
                  (ipath, proto.mimetype))
            if isinstance(data, unicode):
                bdata = data.encode("UTF-8")
            else:
                bdata = data
            if debugDumpData or actAsSingle:
                sys.stdout.write(bdata)
                print()
            sys.exit(0)
        else:
            print("Got error, eof %d"%eof, file=sys.stderr)
            sys.exit(1)

    ecnt = 0   
    while 1:
        ok, data, ipath, eof = extract.getnext(params)
        if ok:
            ecnt = ecnt + 1
            debprint("== Entry %d ipath %s (mimetype [%s]):" % \
                  (ecnt, ipath, proto.mimetype))
            if isinstance(data, unicode):
                bdata = data.encode("UTF-8")
            else:
                bdata = data
            if debugDumpData:
                sys.stdout.write(bdata)
                print()
            if eof != RclExecM.noteof:
                sys.exit(0)
        else:
            print("Not ok, eof %d" % eof, file=sys.stderr)
            sys.exit(1)
        # Not sure this makes sense, but going on looping certainly does not
        if actAsSingle:
            sys.exit(0)