from typing import Any
import numpy as np
import json
from multiprocessing import Process, RLock
import os
import io
import queue
import transport
from transport import providers

class Store(Process):
    """
    This is the data-store service that will handle read/writes
    """
    dataStore = None
    @staticmethod
    def init(self,**_args):
        if Store.dataStore is None :
            _args = _args['store']
            
        else:
            pass
    @staticmethod
    def reset():
        pass
    
class X12DOCUMENT (Process):    
    """
    X12DOCUMENT class encapsulates functions that will be used to format an x12 (835,837) claim into an object
    """
    _queue = queue.Queue()
    
    class MODE :
        #
        # The following allow us to handle raw content (stream) or a filename
        # The raw content will be wrapped into io.StringIO so that it is handled as if it were a file
        #
        NAMES,STREAM = 'NAMES','STREAM'
    class ConfigHandler :
        def format(self,**_args):
            """
                This function formats variations of an element's parsing rules
                :info   {index,field|label,map}
            """
            
            _info = _args['info']
            _ref = {}
            
            for _item in _info :
                _index = str(_item['index']) 
                _field = _item['field'] if 'field' in _item else None
                _label = _item['label'] if 'label' in _item else None
                if _field :
                    _ref[_index] = {'field':_field}
                elif _label :
                    _ref[_index] = {'label':_label}
            
            return {'@ref':_ref}
        def _getColumnsIndexes(self,_columns,_indexes,_map):
            """
            This function return columns and indexes related if a parsing map is passed
            :param _columns
            :param _indexes
            :param _map     parsing map (field:index)
            """
            # @TODO: insure the lengths are the same for adequate usage downstream ...
            _xcolumns,_xindexes = list(_map.keys()), list(_map.values())
            keys,values = _xcolumns + _columns,_xindexes + _indexes
            _config = dict(zip(keys,values))
                
            _outColumns,_outIndexes = list(_config.keys()),list(_config.values())             
            return _outColumns,_outIndexes
        def _getObjectAtributes(self,_config):
            _field = _config['field'] if 'field' in _config else {}
            _label = _config['label'] if 'label' in _config else {}
            return _field,_label
        def consolidate(self,**_args):
            #
            # This function overrides the old configuration with the new configuration specifications
            #
            
            # _columns,_indexes = [],[]
            _columns,_indexes = _args['columns'],_args['index']
            _map = {}
            _config = _args['config'] if 'config' in _args else {}
            _field,_label = self._getObjectAtributes(_config)
            
            if 'map' in _config :
                _map = _args['config']['map'] 
                _columns,_indexes = self._getColumnsIndexes(_columns,_indexes,_map)
              
            if '@ref' in _config :
                # _columns,_indexes = [],[]
                _row = _args['row']  
                
                _ref = _config['@ref']              
                
                for _anchor in _ref:
                    
                    if _anchor == _row[1].strip() :
                        _field,_label = self._getObjectAtributes(_ref[_anchor])
                        
                        _map = _ref[_anchor]['map'] if 'map' in _ref[_anchor] else {}
                       
                        if _map :
                            _columns,_indexes = self._getColumnsIndexes([],[],_map)
                        else:
                            # print ([_anchor,_indexes,_columns])  
                            _map = dict(zip(_columns,_indexes))
                            pass
                           
                        break
                # _columns,_indexes = _columns + _map.keys()
               
            _out =  {'columns':_columns,'index':_indexes,'field':_field,'label':_label}
            return _out
        def legacy(self,**_args):
            #
            # This function returns the legacy configuration (default parsing)
            #
            
            _config = _args['config'] if 'config' in _args else {}
            _field,_label = self._getObjectAtributes(_config)
            _columns,_indexes = [],[]
            if 'map' in _config :
                
                _columns = list(_config['map'].keys())
                _indexes = list(_config['map'].values())
            
            return {'columns':_columns,'index':_indexes,'field':_field,'label':_label}
        def override(self,**_args):
            return _args['columns'],_args['indexes']
    def __init__(self,**_args):
        super().__init__()
        self._mode = _args['mode'] if 'mode' in _args else 'NAMES'
        self.lastelement = {}  # This to store in the loop
        if 'files' in _args :
            self.files = _args['files']
        self._config = _args['config'] if 'config' in _args else {}
        
        #
        # NM1 is a fluid type and thus will be cached in order to recreate the hierarchy
        # @TODO:
        #   -add this to the configuration
        #
        self._hierarchy = {'NM1':['N1','N2','N3','N4']}
        self._document = []
        
        self._x12FileType = None
        self._configHandler = X12DOCUMENT.ConfigHandler()

        #
        #-- The files need to be classified, the files need to be either claims or remits 
        #
        if 'store' not in self._config :
            self._store_args    = _args['store'] if 'store' in _args else {'provider':providers.CONSOLE}
        else:
            self._store_args = self._config['store']
        
    def init(self,_header):
        """
        Expected Elements must include ST
        """
        pass

    def merge (self,_x,_y):
        """
        This function will merge two objects _x, _y
        """
        _zcols = list(set(_x.keys()) & set(_y.keys())) #--common columns
        
        if _zcols :
            _out = dict(_x,**{})
            for _key in _y.keys() :
                if not _key in _zcols :
                    
                    _out[_key] = _y[_key]
                else:
                    if type(_out[_key]) == list :
                        _out[_key] += _y[_key]
                    elif type(_out[_key]) == dict:
                        _out[_key] = dict(_out[_key],**_y[_key])
                    else:
                        _out[_key] = _y[_key]
            
            return _out 
        else:
            
            return dict(_x,**_y)
        
    def split(self,content):
        """
        This function will split the content of an X12 document into blocks and headers
        :content    x12 document in raw format (text)
        """
        #_content = content.split('~')
        _content  = content.split('HL')
        xchar = '~\n' if '~\n' in _content[0] else '~'
        _header = _content[:1][0].split(xchar) #.split('~')
        
        _blocks = ['HL*'+_item for _item in _content[1:]]
        # xchar = '~\n' if '~\n' in _blocks[0] else '~'
            
        _blocks = [_item.split(xchar) for _item in _blocks ]
        
        # for row in _content :
        #     if not _blocks and not row.startswith('HL') :
        #         _header.append(row)
        #     else:
        #         _blocks.append(row)
        
        return {'header':_header,'blocks':_blocks}        
    def parse (self,columns,index,**_args):
        """
        This function encapulates how an x12 document element will be processed
        :columns    list of attributes that make up the object
        :index      indexes of the said items in the element
        :_args
            - row       raw x12 element (string)
            - config    configuration of the element. his should indicate functions to apply against function
        """
        _ELEMENT = _args['row'][0]
        
        #
        # get the right configuration from the _config object
        _config = _args['config'][_ELEMENT] if _ELEMENT in _args['config'] else {}
        
        # _field = _config['field'] if 'field' in _config else None
        # _label = _config['label'] if 'label' in _config else None
        _map = _config['map'] if 'map' in _config else {}
        #
        # Let's see if overriding the fields/labels isn't necessary
        
             
        # columns, index,_refField,_refLabel = self._configHandler.merge(row=_args['row'],columns=columns,index=index,config=_config)
        # _field = _field if not _refField else _refField
        # _label = _label if not _refLabel else _refLabel
        
        #
        # @TODO:
        # There should be a priority in parsing i.e plugin - config
        #
        if 'plugin-context' in _args :
            _config = _args['plugin-context'] #dict(_config,**_args['plugin-context'])
            
        _outInfo = self._configHandler.consolidate(row=_args['row'],columns=columns,index=index,config=_config)
        
            
        _field,_label = _outInfo['field'],_outInfo['label']
        _columns,_index = _outInfo['columns'],_outInfo['index']
                          
        
        if 'row' in _args:
            _row = _args['row'] if type(_args['row']) == list else _args['row'].split('*')
            
            _index = np.array(_index)
            
            #
            # Sometimes the _row doesn't have all expected indexes, we will compensate
            # This allows to minimize parsing errors as it may relate to disconnects between configuration and x12 element variations (shitty format)
            #
            if np.max(_index) > len(_row) -1  :
                _delta = 1 + np.max(_index) - len(_row)
                _row = _row + np.repeat('',_delta).tolist()
            _row = np.array(_row)
            
            
            _info =  dict(zip(_columns,_row[_index].tolist()))           
            _document = _args['document'] if 'document' in _args else {}
           
            #
            # @TODO:
            # Apply parsing/casting function to the object retrieved
            #    _apply(_info)   #-- the object will be processed accordingly
            #
            
            #
            # @TODO:
            #   The objects parsed must be augmented against the appropriate ones e.g: NM1 <- N1,N2,N3,N4
            #   - Find a way to drive this from a configuration ...
            #
            if _field  :

                if not  _field in _document :
                    _item =  {_field:_info}
                else:
                    _item =  self.merge(_document[_field],_info)
            elif _label :
                if not _label in _document :
                    _item =  {_label:[_info]}
                else:
                    _item =  _document[_label] + [_info]
            else:
                _item =  _info
                
 
            if _ELEMENT in self._hierarchy  and _field:
                # print ([_field,_item])
                
                self.lastelement = _item
                pass
            else:
                for key in self._hierarchy :
                    if _ELEMENT in self._hierarchy[key] :
                        
                        _ikey       = list(self.lastelement.keys())[0]
                        _oldinfo    = self.lastelement[_ikey]
                        if type(_oldinfo) != dict :
                            #
                            # This is we should log somewhere to suggest an issue happened
                            #
                            # self.log(action='error',input=_row)
                            pass
                        else:
                            _item  = {_ikey: self.merge(_oldinfo,_item)}
                        
                        break
                pass
            return _item
        else:
            #
            #
            print (_config)
            return columns    
    def elements(self):
        """
        This function returns elements that are supported as specified by X12 standard
        """
        return [_name for _name in dir(self) if not _name.startswith('_') and not _name.islower() ]
    def pointers(self):
        """
        This function returns pointers associated with each element ...
        :return Object of Element:Function
        """
        _attr = self.elements()
        _pointers = [getattr(self,_name) for _name in _attr]
        return dict(zip(_attr,_pointers))

    def set(self,_info,_document,_config):
        _attrName,_attrType = None,None
        
        if 'label' in _config :
            _attrType = 'label'
            _attrName = _config['label']
        elif 'field' in _config :
            _attrType = 'field'
            _attrName = _config['field']
        
        if _attrName :
            if _attrName not in _document :
                _document[_attrName]  = [] if _attrType == 'label' else {}
                
            #
            # @TODO: make sure we don't have a case of an attribute being overridden
            if type(_document[_attrName]) == list  :
                _document[_attrName] += [_info]
            else:
                _document[_attrName] = dict(_document[_attrName],**_info)
            # _document[_attrName] += [_info] if _attrType == 'label' else dict(_document[_attrName],**_info)
            
            return _document
        
        return dict(_document,**_info)

        pass   
    def log (self,**_args):
        print(_args)
    def parseBlocks (self,_blocks,_header):
        """
        This function extracts blocks and returns them to the caller, 
        Blocks of a document are made of transactional loops, that constitute a patients claim
        """
        _tmp = {}
        _documents = []
        for _content in _blocks :
            
            
            _body = self.apply(_content,header=_header)  
            
            _doc = self.merge(_header,_body)
            # self.log(action='parse',section='body',input=_content[0])
            if _doc  and 'claim_id' in _doc:                    
                # X12DOCUMENT._queue.put(_document)
                # self.log(action='parse',section='document')
                _documents += [self.merge(_tmp,_doc)]
                _tmp = {}
            else:
                #
                # The document is being built and not yet ready
                _tmp = self.merge(_tmp,_doc)                

        return _documents
    def run(self):
        """
        This function will trigger the workflow associated with a particular file
        """
        for _filename in self.files :
            # self.log(action='parse',section='file',input=_filename)
            try:
                _documents = []
                _parts = []
                
                if os.sep in _filename and os.path.exists(_filename) :
                    _reader = open(_filename)
                else:
                    #
                    # This is a stream, we are wrapping it into an appropriate structure
                    #
                    _reader = io.StringIO(_filename)
                    
                
                #
                # Let us log the mode we have set ...
                            
                _content = _reader.read()
                if hasattr(_reader,'close') :
                    _reader.close()
                _info   = self.split(_content)
                _fileType=self.init(_content)
                _header = self.apply(_info['header'])
                if _info['blocks'] :
                    #
                    # processing blocks for the current claim 
                    #
                    _documents = self.parseBlocks(_info['blocks'],_header)
                    
            except Exception as e:
                #
                # @TODO: Log this issue for later analysis ...
                print (e)
                pass
            # #
            # # Let us post this to the documents we have, we should find a place to post it
            # #
            if _documents :
                # print (_header['header'])
                _writer = transport.factory.instance(**self._store_args)
                self.post(document=_documents,writer=_writer)
            
        
    def post(self,**_args):
        """
        This function is intended to post content to a given location
        :param document 
        :param writer
        """  
        _writer = _args['writer'] if 'writer' in _args else None
        _document = _args['document']
        if not _writer:
            X12DOCUMENT._queue.put(_document)
        else:
            
            _writer.write(_document)
    def _getConfig(self,_chunk):
        #
        # Let us determine what kind of file we are dealing with, so we can extract the configuration
        # For this we need to look for the ST loop ...
        #
        
        line = [line for line in _chunk if line and line[:2] == 'ST' ]
        
        if line :
            # 
            # We found the header of the block, so we can set the default configuration
            #
            self._x12FileType = line[0].split('*')[1].strip()
        _config = {}
        if self._x12FileType :
            _config = self._config[self._x12FileType]
       
        return _config  
         
    def apply(self,_chunk, header = {}):
        """
        _chunks are groups of elements split by HL, within each chunk are x12 loops HL,CLM,ISA
        """
        
            
        _document,_cached = {},{}
        _pointers = self.pointers()
        _config = self._getConfig(_chunk) 
        #
        # The configuration comes from the file, let's run this in merge mode
        # _config = self._configHandler.merge
        _pid = None
        for line in _chunk :
            
            segments = line.split('*')
            
            _ELEMENT = segments[0] 
           
            if _ELEMENT not in _pointers  or not _ELEMENT:
                continue
            if  _ELEMENT in ['HL','CLM','ISA'] or not _pid:
                _pid = _ELEMENT
            if _pid not in _cached :
                _cached [_pid] = {}
            
            _pointer = _pointers[_ELEMENT]
            
            _args = {'row':segments,'document':_document,'header':header,'config':(_config)}
            
            
            _parsedLine = _pointer(**_args)
            
            
            if _pid in _cached :
                _cached[_pid] = self.merge(_cached[_pid],_parsedLine)
            else:
                _cached[_pid] = _parsedLine
            
        
        #
        # Let's create the documents as we understand them to be
        # @TODO: Create a log so there can be visibility into the parser
        #
        _document = {}
        for _id in _cached :  
            #  print ('patient' in _cached[_id] )    
            
            _document = self.merge(_document,_cached[_id])
        
        return _document