#!/usr/bin/env python3
# encoding: utf-8
#

"""
userconfig.py

Created by Marcus Stoegbauer on 2013-01-10.
"""

import sys
import os
import tempfile
import re
import getopt
import time
import subprocess

# 
import Userconfig.cfgfile as cfgfile
from Userconfig.checks import Checks
import Userconfig.Tools as Tools

debug = Tools.Debug()

classchecks = Checks()
cfg = cfgfile.Conf()

help_message = """
-h help
-v verbose level (multiple v for higher level)
-c userconfig.cfg config file
"""


class Usage(Exception):
    def __init__(self, msg):
        self.msg = msg


def workconf(directory, depth=2):
    """walks through directory, collecting all filenames, returns list of all filenames"""
    dirs = os.listdir(directory)
    ret = []
    debug.debug("   ================ workconf ===============", 1)
    debug.debug("   Finding files in directory %s." % directory, 4)
    for d in dirs:
        name = directory+"/"+d
        if os.path.isdir(name):
            # fixme: create name if it does not exist
            workconf(name, depth+1)
        if name.endswith(".swp"):
            continue
        if d == ".svn":
            continue
        ret.append(name)
        debug.debug("   +++ Found file %s in directory %s" % (name, directory), 4)
    debug.debug("   ================ workconf ===============", 1)
    return ret


def workdir(directory):
    """walks through all host classes, checking if the classes directory exists in directory
       then collect all filenames within this directory and return a dict of all files for this
       directory
    """
    debug.debug("   ================ workdir ===============", 1)
    debug.debug("   Working on directory %s" % directory, 3)
    # skip directory if no CONFIGFILE present
    if not os.path.isfile(directory+"/"+cfg.get("Main", "configfile")):
        debug.debug("   --- No %s in %s, skipping." % (cfg.get("Main", "configfile"), directory), 1)
        return {},None

    # get config file for directory
    dir_config = Tools.get_config(directory + "/" + cfg.get("Main", "configfile"))
    if not dir_config:
        debug.debug("   --- Cannot read %s in %s, skipping." % (cfg.get("Main", "configfile"), directory), 1)
        return {},None

    destdir = dir_config.get("Main","dest")
    # destfiles is a dict of all files that will be created from the classes config
    # key is the destination filename, values are all classes filenames that are used to
    # build the file
    destfiles = {}
    # FIXME: reverse_order should really be a bool in .cfg, implement variable types in cfg file
    reverse_sort = False
    try:
        reverse_sort = (dir_config.get("Main", "reverse") == 'True')
    except ValueError:
        reverse_sort = False

    if os.access(directory + "/install.sh", os.X_OK):
        subprocess.call([directory + "/install.sh"])

    # walk through all know classes in directory and find filenames
    for h in classchecks.__classes_for_host__(reverse_sort):
        # build classes directory
        if h[0] != "":
            classdir = directory+"/"+h[0]+"_"+h[1]
        else:
            classdir = directory+"/"+h[1]
        debug.debug("   ??? Looking for directory %s." % classdir, 4)
        # if class directory exists
        if os.path.isdir(classdir):
            debug.debug("   +++ Found directory %s, getting files." % classdir, 4)
            # get list of files within this class directory
            tempfiles = workconf(classdir)
            debug.debug("   +++ Got %d files: %s." % (len(tempfiles), str(tempfiles)), 4)
            # put files into dict
            for f in tempfiles:
                destname = destdir+os.path.basename(f)  # destination filename
                if not destname in destfiles:
                    destfiles[destname] = []
                destfiles[destname].append(f) # append each file to dict
                debug.debug("   +++ Added file to %s, now %d files: %s" % (destname, len(destfiles[destname]), destfiles[destname]), 4)

    debug.debug("   === workdir: %s, Files: %s" % (directory, str(destfiles)), 3)
    debug.debug("   ================ workdir ===============", 1)
    return destfiles, dir_config


def build_file(classfiles, destfile, commentstring):
    """open all classfiles, assemble them and write the contents into a tempfile
      returns the name of tempfile
      :param classfiles:
      :param destfile:
      :param commentstring:
      :return: str
      """
    content = []
    debug.debug("   ================ build_file ===============", 1)
    if commentstring != "":
        debug.debug("   +++ commentstring found, adding header.", 3)
        content.append(commentstring + " " + cfg.get("Main","stamp") + " " + time.strftime("%+") + "\n")

    for f in classfiles:
        debug.debug("   +++ Merging %s." % f, 4)
        fp = open(f, "r")
        filecontent = fp.read()
        fp.close()
        if commentstring == "":
            # look for stamp in content, replace with real stamp
            if re.search(re.escape(cfg.get("Main","stampreplace")), filecontent):
                debug.debug("   +++ commentstring empty, replacing stamp in file", 3)
                filecontent = re.sub(re.escape(cfg.get("Main","stampreplace")), cfg.get("Main","stamp"), filecontent)
        content.append(filecontent)

    (tempfd, tempfilename) = tempfile.mkstemp(prefix=os.path.basename(destfile), dir="/tmp")

    try:
        fp = os.fdopen(tempfd, "w")
    except:
        Tools.error("Cannot write to temporary file %s" % tempfilename)
        os.remove(tempfilename)
        return False
    debug.debug("   +++ Writing merged files into tempfile %s." % tempfilename, 3)
    for block in content:
        fp.write(block)
        fp.write("\n")
    fp.close()
    debug.debug("   ================ build_file ===============", 1)
    return tempfilename


def process_all_files(destfiles, dir_config):
    """processes all files in destfiles, generate files from classes, compare and copy if necessary"""
    debug.debug("   ================ process_all_files ===============", 1)
    for df in destfiles.keys():
        debug.debug("   ??? Processing source files for %s." % df, 2)
        # assemble file to tmp
        commentstring = ""
        if dir_config.check("Main", "commentstring"):
            commentstring = dir_config.get("Main", "commentstring")
            debug.debug("   +++ Found commentstring %s in %s" % (commentstring, df), 3)

        tempfilename = build_file(destfiles[df], df, commentstring)
        if not tempfilename:
            debug.debug("   --- Error while creating temp file for %s, skipping." % df, 1)
            continue
        debug.debug("   +++ Merged files %s for %s into %s" % (str(destfiles[df]), df, tempfilename), 2)

        # diff assembled file and config file
        if Tools.diff(df, tempfilename, commentstring, debug):
            debug.debug("File %s has changed" % df, 0)
            if not Tools.user_config_generated(df, cfg):
                debug.debug("   +++ %s not generated by userconfig, backing up." % df, 2)
                # file not generated from userconfig -> back up
                Tools.backup_file(df, debug)
            # copy tmp file to real location
            debug.debug("Copy %s to %s." % (tempfilename, df), 0)
            Tools.copy_file(tempfilename, df, debug)
        # remove tmp
        debug.debug("   +++ Removing temporary file %s." % tempfilename, 2)
        os.remove(tempfilename)
    debug.debug("   ================ process_all_files ===============", 1)

def main():
    configfile = os.environ['HOME']+"/etc/userconfig.cfg"

    try:
        try:
            opts, args = getopt.getopt(sys.argv[1:], "hdc:v", ["help", "debug", "config="])
        except getopt.GetoptError as msg:
            raise Usage(msg)

        for option, value in opts:
            if option == "-v":
                debug.addverbose()
            if option in ("-h", "--help"):
                raise Usage(help_message)
            if option in ("-d", "--debug.debug"):
                pass
            if option in ("-c", "--config"):
                configfile = value
    except Usage as err:
        Tools.error(sys.argv[0].split("/")[-1] + ": " + str(err.msg))
        Tools.error("\t for help use --help")
        return 2

    debug.debug("Verbose level is %d" % debug.verbose, 1)
    debug.debug("Using configfile %s." % configfile, 1)
    if not os.path.isfile(configfile):
        Tools.error("No config file specified.")
        return 2

    cfg.setdebug(debug)
    cfg.setfilename(configfile)

    debug.debug("================ main ===============", 1)
    tempclasses = ""
    for h in classchecks.__classes_for_host__():
        tempclasses=tempclasses + str(h) + ","
    debug.debug("+++ Current host is in classes %s" % tempclasses, 1)
    configdir = cfg.get("Main", "configdir")
    for d in os.listdir(configdir):
        destfiles = {}
        name = configdir+"/"+d
        debug.debug("+++ Working in %s" % name, 1)
        if not os.path.isdir(name):
            debug.debug("--- %s is not a directory, skipping." % name, 3)
            continue
        elif d.startswith(".svn") or d.startswith(".git"):
            debug.debug("--- %s is .svn or .git, skipping." % name, 3)
            continue
        elif os.path.isfile(name+"/.ignore"):
            debug.debug("--- %s contains file .ignore, skipping." % name, 3)
            continue
        else:
            debug.debug("+++ Processing files in %s" % name, 2)
            (destfiles, dirConfig) = workdir(name)
            if isinstance(destfiles, dict):
                if len(destfiles.keys()) > 0:
                    debug.debug("+++ Building %d files: %s" % (len(destfiles.keys()), destfiles.keys()), 3)
                    process_all_files(destfiles, dirConfig)
            else:
                debug.debug("--- No files found for %s, skipping." % name, 1)


if __name__ == '__main__':
    main()