#!/usr/bin/env python
__doc__ = """
(c) 2018 - 2021 data-transport
steve@the-phi.com, The Phi Technology LLC
https://dev.the-phi.com/git/steve/data-transport.git

This program performs ETL between 9 supported data sources  : Couchdb, Mongodb, Mysql, Mariadb, PostgreSQL, Netezza,Redshift, Sqlite, File
LICENSE (MIT)
Copyright 2016-2020, The Phi Technology LLC

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.


Usage :
	transport --config <path-to-file.json> --procs <number-procs>
@TODO: Create tables if they don't exist for relational databases


"""
import pandas as pd
import numpy as np
import json 
import sys
import transport
import time
from multiprocessing import Process
SYS_ARGS = {}
if len(sys.argv) > 1:
    
    N = len(sys.argv)
    for i in range(1,N):
        value = None
        if sys.argv[i].startswith('--'):
            key = sys.argv[i][2:] #.replace('-','')
            SYS_ARGS[key] = 1			
            if i + 1 < N:
                value = sys.argv[i + 1] = sys.argv[i+1].strip()
            if key and value and not value.startswith('--'):
                SYS_ARGS[key] = value
                
        
        i += 2

class Post(Process):
	def __init__(self,**args):
		super().__init__()
		self.PROVIDER = args['target']['type']
		self.writer = 	transport.factory.instance(**args['target'])
		self.rows 	=	 args['rows']
	def run(self):
		_info = {"values":self.rows} if 'couch' in self.PROVIDER else self.rows		
		self.writer.write(_info)
		self.writer.close()

		
class ETL (Process):
	def __init__(self,**_args):
		super().__init__()
		self.name 	= _args['id']
		self.reader = transport.factory.instance(**_args['source'])
		self._oargs = _args['target'] #transport.factory.instance(**_args['target'])
		self.JOB_COUNT =  _args['jobs']
		self.jobs = []
		# self.logger = transport.factory.instance(**_args['logger'])
	def log(self,**_args) :
		_args['name']  = self.name
		print (_args)
	def run(self):
		idf = self.reader.read()
		idf = pd.DataFrame(idf)
		idf.columns = [str(name).replace("b'",'').replace("'","").strip() for name in idf.columns.tolist()]
		self.log(rows=idf.shape[0],cols=idf.shape[1],jobs=self.JOB_COUNT)

		#
		# writing the data to a designated data source 
		#
		try:
			self.log(module='write',action='partitioning')
			rows = np.array_split(np.arange(idf.shape[0]),self.JOB_COUNT)
			
			for i in rows :
				_id = 'segment #'.join([str(rows.index(i)),self.name])
				segment = idf.loc[i,:] #.to_dict(orient='records')
				proc = Post(target = self._oargs,rows = segment,name=_id)
				self.jobs.append(proc)
				proc.start()

			self.log(module='write',action='working ...',name=self.name)
			
		except Exception as e:
			print (e)
		
	def is_done(self):
		self.jobs = [proc for proc in self.jobs if proc.is_alive()]
		return len(self.jobs) == 0
def apply(_args) :
	"""
	This function will apply a set of commands against a data-store. The expected structure is as follows :
	{"store":...,"apply":[]}	
	"""
	handler = transport.factory.instance(**_args['store'])
	for cmd in _args['apply'] :
		handler.apply(cmd)
	handler.close()
if __name__ == '__main__' :
	_info = json.loads(open (SYS_ARGS['config']).read())
	index = int(SYS_ARGS['index']) if 'index' in SYS_ARGS else None
	procs = []
	for _config in _info :
		if 'source' in SYS_ARGS :
			_config['source'] = {"type":"disk.DiskReader","args":{"path":SYS_ARGS['source'],"delimiter":","}}

		_config['jobs']  = 10 if 'jobs' not in SYS_ARGS else int(SYS_ARGS['jobs'])
		etl = ETL (**_config)
		etl.start()
		procs.append(etl)
		if index and _info.index(_config) == index :
			break
	#
	#
	N = len(procs)
	while procs :
		procs = [thread for thread in procs if not thread.is_done()]
		if len(procs) < N :
			print (["Finished ",(N-len(procs)), " remaining ", len(procs)])
			N = len(procs)
		time.sleep(1)
	print ("We're done !!")