#!/usr/bin/env python
# -*- coding: utf-8 -*-
# Authors: Titouan Parcollet

# Imports.
import sys; sys.path += [".", ".."]
import argparse                             as Ap
import logging                              as L
import numpy                                as np
import os, pdb, sys
import time
import tensorflow as tf
from keras.backend.tensorflow_backend import set_session
__version__ = "1.0.0"



#
# Message Formatter
#

class MsgFormatter(L.Formatter):
    """Message Formatter
    
    Formats messages with time format YYYY-MM-DD HH:MM:SS.mmm TZ
    """
    
    def formatTime(self, record, datefmt):
        t           = record.created
        timeFrac    = abs(t-long(t))
        timeStruct  = time.localtime(record.created)
        timeString  = ""
        timeString += time.strftime("%F %T", timeStruct)
        timeString += "{:.3f} ".format(timeFrac)[1:]
        timeString += time.strftime("%Z",    timeStruct)
        return timeString



#############################################################################################################
##############################                   Subcommands               ##################################
#############################################################################################################

class Subcommand(object):
    name  = None
    
    @classmethod
    def addArgParser(cls, subp, *args, **kwargs):
        argp = subp.add_parser(cls.name, usage=cls.__doc__, *args, **kwargs)
        cls.addArgs(argp)
        argp.set_defaults(__subcmdfn__=cls.run)
        return argp
    
    @classmethod
    def addArgs(cls, argp):
        pass
    
    @classmethod
    def run(cls, d):
        pass


class Screw(Subcommand):
    """Screw around with me in Screw(Subcommand)."""
    name = "screw"
    
    @classmethod
    def run(cls, d):
        print(cls.__doc__)


class Train(Subcommand):
    name = "train"
    
    LOGLEVELS = {"none":L.NOTSET, "debug": L.DEBUG, "info": L.INFO,
                 "warn":L.WARN,   "err":   L.ERROR, "crit": L.CRITICAL}
    
    
    @classmethod
    def addArgs(cls, argp):
        argp.add_argument("-d", "--datadir",        default=".",                type=str,
            help="Path to datasets directory.")
        argp.add_argument("-w", "--workdir",        default=".",                type=str,
            help="Path to the workspace directory for this experiment.")
        argp.add_argument("-l", "--loglevel",       default="info",             type=str,
            choices=cls.LOGLEVELS.keys(),
            help="Logging severity level.")
        argp.add_argument("-s", "--seed",           default=0xe4223644e98b8e64, type=long,
            help="Seed for PRNGs.")
        argp.add_argument("--summary",     action="store_true",
            help="""Print a summary of the network.""")
        argp.add_argument("--model",              default="real",          type=str,
            choices=["quaternion", "real"],
            help="Dataset Selection.")
        argp.add_argument("--dropout",              default=0,                  type=float,
            help="Dropout probability.")
        argp.add_argument("-n", "--num-epochs",     default=1000,                type=int,
            help="Number of epochs")
        argp.add_argument("--start-filter", "--sf", default=11,                 type=int,
            help="Number of feature maps in starting stage")
        argp.add_argument("--num-layers", "--nl",   default=10,                 type=int,
            help="Number of layers")    
        argp.add_argument("--act",                  default="relu",             type=str,
            choices=["relu","sigmoid","tanh"],
            help="Activation.")
        argp.add_argument("--aact",                 default="none",          type=str,
            choices=["none","prelu"],
            help="Advanced Activation.")
        argp.add_argument("--quat-init",            default='quaternion',  type=str,
            help="Initializer for the quaternion kernel.")
        optp = argp.add_argument_group("Optimizers", "Tunables for all optimizers")
        optp.add_argument("--optimizer", "--opt",   default="nag",              type=str,
            choices=["sgd", "nag", "adam", "rmsprop"],
            help="Optimizer selection.")
        optp.add_argument("--clipnorm", "--cn",     default=1.0,                type=float,
            help="The norm of the gradient will be clipped at this magnitude.")
        optp.add_argument("--clipval",  "--cv",     default=1.0,                type=float,
            help="The values of the gradients will be individually clipped at this magnitude.")
        optp.add_argument("--l2",                   default=0,                  type=float,
            help="L2 penalty.")
        optp.add_argument("--lr",                   default=1e-4,               type=float,
            help="Master learning rate for optimizers.")
        optp.add_argument("--momentum", "--mom",    default=0.9,                type=float,
            help="Momentum for optimizers supporting momentum.")
        optp.add_argument("--decay",                default=0,                  type=float,
            help="Learning rate decay for optimizers.")
        optp = argp.add_argument_group("Adam", "Tunables for Adam optimizer")
        optp.add_argument("--beta1",                default=0.9,                type=float,
            help="Beta1 for Adam.")
        optp.add_argument("--beta2",                default=0.999,              type=float,
            help="Beta2 for Adam.")
        optp.add_argument("--device",                default="0",              type=str,
            help="CUDA Device, starting at 0.")
        optp.add_argument("--gpus",                default=1,              type=int,
            help="Number of GPUs to be used, starting at 1")
        optp.add_argument("--memory",                default=1.0,              type=float,
            help="Memory to be allocated on the selected device, only for tensorflow backend, from 0 to 1")
        optp.add_argument("--save-prefix",                default="",              type=str,
            help="Save prefix for resuming and saving best model")

    @classmethod
    def run(cls, d):
        if not os.path.isdir(d.workdir):
            os.mkdir(d.workdir)
        
        logDir = os.path.join(d.workdir, "logs")
        if not os.path.isdir(logDir):
            os.mkdir(logDir)
        
        logFormatter      =   MsgFormatter ("[%(asctime)s ~~ %(levelname)-8s] %(message)s")
        
        stdoutLogSHandler = L.StreamHandler(sys.stdout)
        stdoutLogSHandler   .setLevel      (cls.LOGLEVELS[d.loglevel])
        stdoutLogSHandler   .setFormatter  (logFormatter)
        defltLogger       = L.getLogger    ()
        defltLogger          .setLevel     (cls.LOGLEVELS[d.loglevel])
        defltLogger          .addHandler   (stdoutLogSHandler)
        
        trainLogFilename  = os.path.join(d.workdir, "logs", "train.txt")
        trainLogFHandler  = L.FileHandler  (trainLogFilename, "a", "UTF-8", delay=True)
        trainLogFHandler     .setLevel     (cls.LOGLEVELS[d.loglevel])
        trainLogFHandler     .setFormatter (logFormatter)
        trainLogger       = L.getLogger    ("train")
        trainLogger          .setLevel     (cls.LOGLEVELS[d.loglevel])
        trainLogger          .addHandler   (trainLogFHandler)
        
        entryLogFilename  = os.path.join(d.workdir, "logs", "entry.txt")
        entryLogFHandler  = L.FileHandler  (entryLogFilename, "a", "UTF-8", delay=True)
        entryLogFHandler     .setLevel     (cls.LOGLEVELS[d.loglevel])
        entryLogFHandler     .setFormatter (logFormatter)
        entryLogger       = L.getLogger    ("entry")
        entryLogger          .setLevel     (cls.LOGLEVELS[d.loglevel])
        entryLogger          .addHandler   (entryLogFHandler)
        
        np.random.seed(d.seed % 2**32)
        
        import training;training.train(d)




#############################################################################################################
##############################               Argument Parsers               #################################
#############################################################################################################

def getArgParser(prog):
    argp = Ap.ArgumentParser(prog        = prog,
                             usage       = None,
                             description = None,
                             epilog      = None,
                             version     = __version__)
    subp = argp.add_subparsers()
    argp.set_defaults(argp=argp)
    argp.set_defaults(subp=subp)
    
    # Add global args to argp here?
    # ...
    
    
    # Add subcommands
    for v in globals().itervalues():
        if(isinstance(v, type)       and
           issubclass(v, Subcommand) and
           v != Subcommand):
            v.addArgParser(subp)
    
    # Return argument parser.
    return argp



#############################################################################################################
##############################                      Main                   ##################################
#############################################################################################################

def main(argv):
    sys.setrecursionlimit(10000)
    d = getArgParser(argv[0]).parse_args(argv[1:])
    return d.__subcmdfn__(d)
if __name__ == "__main__":
    main(sys.argv)