#!/usr/bin/python

DESCRIPTION='''check cell institutions and fix missing'''

#std libs
import os, sys, re, string, pwd, grp

FIX=1 #0: just check, 1: fix missing

def main():
    if checkdir(FIX, '/etc/cell'):
        checkown(FIX, '/etc/cell', 'root', 'wheel', 'r')
        checkfile(FIX, '/etc/cell/shortname', 'root', 'wheel')
    if checkdir(FIX, '/etc/allcells'):
        checkown(FIX, '/etc/allcells', 'transfer', '', 'r')

def checkfile(FIX, PATH, OWNER='', GROUP='', PERMISSIONS=''):
    print "checking whether file exists: ", PATH
    SUCCESS=1
    if not os.path.isfile(PATH):
        sys.stderr.write('file does not exist: '+PATH+'\n')
        SUCCESS=0
        if FIX:
	    sys.stderr.write('no fix available, create and fill yourself: ' +PATH+ '\n')
    #TODO: check owner, group, permissions

    return SUCCESS

def checkdir(FIX, dir):
    print "checking whether directory exists: ", dir
    SUCCESS=1
    if not os.path.isdir(dir):
        sys.stderr.write('directory does not exist: '+dir+'\n')
        if FIX:
            try:
                os.makedirs(dir)
                sys.stderr.write('directory created: ' +dir+ '\n')
            except OSError,e:
                sys.stderr.write('directory not created: ' +dir+ ', ' +str(e)+ '\n')
                SUCCESS=0
        else:
            SUCCESS=0

    return SUCCESS

def checkown(FIX, file, owner, group='', options=''):
    #options:r  recursive but do not follow symlinks
    SUCCESS=1
    if 'r' in options:
        FILES=os.popen('find '+file).read().strip()
        for singlefile in FILES.split('\n'):
            if not checkown_singlefile(FIX, singlefile, owner, group):
                SUCCESS=0
    else:
        if not checkown_singlefile(FIX, file, owner, group):
            SUCCESS=0

    return SUCCESS

def checkown_singlefile(FIX, file, owner, group=''):
    SUCCESS=1
    STAT=os.lstat(file)
    if owner:
        print "checking ownership: ", file
        UID=pwd.getpwnam(owner)[2]
        if not UID == STAT.st_uid:
            sys.stderr.write('not owned by '+owner+': ' +file+ '\n')
            if FIX:
                try:
                    os.lchown( file, UID, STAT.st_gid )
                    sys.stderr.write('ownership changed: ' +file+ '\n')
                except OSError,e:
                    sys.stderr.write('ownership not changed: ' +file+ ', ' +str(e)+ '\n')
                    SUCCESS=0
            else:
                SUCCESS=0

    if group:
        print "checking group-ownership: ", file
        GID=grp.getgrnam(group)[2]
        if not GID == STAT.st_gid:
            sys.stderr.write('not owned by group '+group+': ' +file+ '\n')
            if FIX:
                try:
                    os.lchown(file, STAT.st_uid, GID )
                    sys.stderr.write('group-ownership changed: ' +file+ '\n')
                except OSError,e:
                    sys.stderr.write('group-ownership not changed: ' +file+ ', ' +str(e)+ '\n')
                    SUCCESS=0
            else:
                SUCCESS=0
        
    return SUCCESS

def checklink(FIX, link, dst=''):
    SUCCESS=1
    pass #TODO

    return SUCCESS

if __name__ == "__main__":
    main()