#!/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
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.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])

		#
		# 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)
			jobs = []
			for i in rows :
				segment = idf.loc[i,:].to_dict(orient='records')
				proc = Post(target = self._oargs,rows = segment)
				jobs.append(proc)
				proc.start()

			self.log(module='write',action='working ...')
			while jobs :
				jobs = [proc for proc in jobs if proc.is_alive()]
				time.sleep(2)
			self.log(module='write',action='completed')
		except Exception as e:
			print (e)
if __name__ == '__main__' :
	_info = json.loads(open (SYS_ARGS['config']).read())
	if 'source' in SYS_ARGS :
		_info['source'] = {"type":"disk.DiskReader","args":{"path":SYS_ARGS['source'],"delimiter":","}}
	
	for _config in _info :
		_config['jobs']  = 10 if 'jobs' not in SYS_ARGS else SYS_ARGS['jobs']
		etl = ETL (**_config)
		etl.start()