data_manager.py

'''
Created on Apr 25, 2019

@author: Javier Arroyo

This module contains the Data_Manager class with methods to add and
access test case data within the resources folder of the
test case FMU.

'''

import matplotlib.pyplot as plt
import pandas as pd
import numpy as np
import zipfile
from scipy import interpolate
import warnings
import os
import json

class Data_Manager(object):
    ''' This class has the functionality to store and retrieve the data
    into and from the resources folder of the test case FMU.

    To store the data, it assumes csv files are within a Resources directory
    located in the same directory as the FMU.  All csv files are searched for
    columns with keys following the BOPTEST data convention specified in the
    categories.json file.

    To retrieve the data, it loads timeseries data and kpis.json into the
    TestCase object managing the FMU upon deployment and provides methods
    to retrieve it as needed for forecasting purposes or for KPI calculations.

    '''

    def __init__(self, testcase=None):
        '''Initialize the Data_Manager class.

        Parameters
        ----------
        testcase: BOPTEST TestCase object, default is None
            Used if loading or retrieving data from a test case FMU.
            Not used if compiling test case data into an FMU.
            Default is None.

        '''

        # Point to the test case object
        self.case = testcase

        # Find path to data directory
        data_dir = os.path.join(\
            os.path.split(os.path.split(os.path.abspath(__file__))[0])[0],
            'data')

        # Load possible data keys
        with open(os.path.join(data_dir,'categories.json'),'r') as f:
            self.categories = json.loads(f.read())

    def _get_zone_identifiers(self):
        '''Get all zone identifiers from the kpis.json file generated
        by the parser. The zone identifiers can be used, for instance,
        to check that the right data variables are saved in the
        compiled fmu or loaded from the fmu into the test case object.

        Returns
        -------
        zone_ids: list
            List with all zone identifiers in the building model.


        '''

        # Find the kpi.json
        try:
            # Case when we are loading data into a test case
            kpi_json = self.case.kpi_json
        except:
            # Case when we are saving data into a compiled fmu
            with open(self.kpi_path,'r') as f:
                kpi_json = json.loads(f.read())

        # Initialize list with zone identifiers
        zone_ids = []

        # Go through kpi_json to find zone identifiers
        for source in kpi_json.keys():
            if '[' and ']' in source:
                zone_id = source[source.find('[')+1:source.find(']')]
                if zone_id not in zone_ids:
                    zone_ids.append(zone_id)

        return zone_ids

    def _get_zone_and_boundary_keys(self):
        '''This method returns all possible data keys differentiating
        between zone-related keys and boundary data keys.
        The zone keys are keys containing a zone identifier such as
        temperature set points, internal gains or occupancy. Boundary
        keys are all the others, i.e. weather, emission factors, or
        prices:
            all_keys = zon_keys + bou_keys

        Returns:
        -------
        zon_keys: list
            All zone-related keys of the form `variable[zone_id]`
            where variable is one of the variables in `self.categories`
            and `zone_id` is the zone identifier.
        bou_keys: list
            All boundary data keys that do not need a zone identifier

        '''

        # Find zone and boundary keys
        zon_keys = []
        bou_keys = []

        # Get the zone identifiers
        zone_ids = self._get_zone_identifiers()

        for category in self.categories:
            if category in ['occupancy','internalGains','setpoints']:
                for var in self.categories[category]:
                    zon_keys.extend([var + '['+ zone_id+']' for zone_id in zone_ids])
            else:
                bou_keys.extend(self.categories[category])

        return zon_keys, bou_keys

    def _append_csv_data(self):
        '''Append data from any .csv file within the Resources folder
        of the testcase. The .csv file must contain a 'time' column
        in seconds from the beginning of the year and one of the
        keys defined within categories.kpis, or the combination of
        these variable keys with a zone identifier in the format:
        variable[zone_identifier]. Other data without this format will
        raise an error to prevent from unnecessary data to be stored
        in the test case FMU or from data columns that have not the
        allowed key format.

        '''

        # Keep track of the data already appended to avoid duplication
        appended = {}

        # Get zone and boundary data keys allowed
        zon_keys, bou_keys = self._get_zone_and_boundary_keys()

        # Search for .csv files in the resources folder
        for f in self.files:
            if f.endswith('.csv'):
                df = pd.read_csv(f, comment='#')
                cols = df.keys()
                if 'time' in cols:
                    for col in cols.drop('time'):
                        # Raise error if col already appended
                        if col in appended.keys():
                            raise ReferenceError('{0} in multiple files within the Resources folder.'\
                                                 'These are: {1}, and {2}'.format(col, appended[col], f))
                        # Raise error if there are col keys that are not allowed
                        elif not( (col in zon_keys) or (col in bou_keys) ):
                            raise KeyError('The data column {0} from file {1} '\
                                           'does not match any of the allowed column keys and therefore '\
                                           'it cannot be saved within the compiled fmu. Test case data '\
                                           'variables are used for forecasting and KPI calculation. If '\
                                           'you want this variable to be part of the test case data '\
                                           'make sure that the column has a key with any of the specified '\
                                           'formats in categories.json and that, if it is a zone related '\
                                           'key, it is in the format: variable[zone_identifier] '.format(col,f))
                        else:
                            appended[col] = f
                    # Store the data in the FMU as col checks passed
                    df.to_csv(f+'_testcase', index=False)
                    file_name = os.path.split(f)[1]
                    self.z_fmu.write(f+'_testcase',
                        os.path.join('resources',file_name))
                    os.remove(f+'_testcase')
                else:
                    warnings.warn('The following file does not have '\
                    'time column and therefore no data is going to '\
                    'be used from this file as test case data. If your '\
                    'intention is to store data from this file into the '\
                    'test case data, make sure that the file includes a '\
                    'column with time in the header indicating the '\
                    'seconds from the beginning of the year', Warning)
                    print(f)

    def save_data_and_jsons(self, fmu_path):
        '''Store all of the .csv, kpis.json, and days.json test case data within the
        resources folder of the fmu.

        Parameters
        ----------
        fmu_path : string
            Path to the fmu where the data is to be saved. The reason
            to not get this path from the tescase config file is
            that this method is called by the parser before the test
            case is created.

        '''

        # Open the fmu zip file in append mode
        self.z_fmu = zipfile.ZipFile(fmu_path,'a')

        # Find the models directory
        models_dir = os.path.split(os.path.abspath(fmu_path))[0]

        # Find the Resources folder
        resources_dir = os.path.join(models_dir, 'Resources')

        # Find the kpis.json path
        self.kpi_path = os.path.join(models_dir, 'kpis.json')
        # Find the days.json path
        self.days_path = os.path.join(models_dir, 'days.json')
        # Find the config.json path
        self.config_path = os.path.join(models_dir, 'config.json')

        if os.path.exists(resources_dir):
            # Find all files within Resources folder
            self.files = []
            for root, _, files in os.walk(resources_dir):
                for f in files:
                    self.files.append(os.path.join(root,f))

            # Write a copy all .csv files within the fmu resources folder
            self._append_csv_data()
        else:
            warnings.warn('No Resources folder found for this FMU, ' \
                          'No additional data will be stored within the FMU.')

        # Write a copy of the kpis.json within the fmu resources folder
        if os.path.exists(self.kpi_path):
            self.z_fmu.write(self.kpi_path,
                             os.path.join('resources', 'kpis.json'))
        else:
            warnings.warn('No kpis.json found for this test case, ' \
                          'use the parsing/parser.py to get this file or otherwise create it.')

        # Write a copy of the days.json within the fmu resources folder
        if os.path.exists(self.days_path):
            self.z_fmu.write(self.days_path,
                             os.path.join('resources', 'days.json'))
        else:
            warnings.warn('No days.json found for this test case, ' \
                          'use the data/find_days.py to get this file or otherwise create it.')

        # Write a copy of config.json to the fmu resources folder
        if os.path.exists(self.config_path):
            self.z_fmu.write(self.config_path,
                             os.path.join('resources', 'config.json'))
        else:
            warnings.warn('No config.json found for this test case')

        # Close the fmu
        self.z_fmu.close()

    def get_data(self, horizon=24*3600, interval=None, index=None,
                 variables=None, category=None, plot=False):
        '''Retrieve test case data from the fmu. The data
        is stored within the csv files that are
        located in the resources folder of the test case fmu.

        Parameters
        ----------
        horizon : int, default is 24*3600
            Length of the requested forecast in seconds. By default one
            day will be used.
        interval : int, default is None
            resampling time interval in seconds. If None,
            the test case step will be used instead.
        index : numpy array, default is None
            time vector for which the data points are requested.
            The interpolation is linear for the weather data
            and forward fill for the other data categories. If
            index is None, the default case step is used as default.
        variables : list, default is None
            Specific set of variables requested to the data manager.
            If None, the data manager will not filter by variables, but it
            can still filter using the `category` argument.
        category : string, default is None
            Type of data to retrieve from the test case.
            If None it will return all available test case
            data without filtering it by any category.
            The possible options are specified at categories.json.
            This argument cannot be used together with the `variables`
            argument.
        plot : Boolean, default is False
            True if desired to plot the retrieved data

        Returns
        -------
        data: dict
            Dictionary with the requested forecast data
            {<variable_name>:<variable_forecast_trajectory>}
            where <variable_name> is a string with the variable
            key and <variable_forecast_trajectory> is a list with
            the data values. 'time' is included as a variable

        Notes
        -----
        The loading and pre-processing of the data happens only
        once (at load_data_and_jsons) to reduce the computational
        load during the co-simulation

        '''

        # Filter the requested data columns
        if variables is not None:
            if category is not None:
                raise ValueError('You cannot use category and variables '\
                                 'at the same time to filter data. Use '\
                                 'either one or the other. ')
            cols = variables
            data_slice = self.case.data.loc[:,cols]
        elif category is not None:
            cols = [col for col in self.case.data if \
                    any(col.startswith(key) for key in self.categories[category])]
            data_slice = self.case.data.loc[:,cols]
        else:
            data_slice = self.case.data

        # If no index use horizon and interval
        if index is None:
            # Use the test case start time
            start = self.case.start_time
            stop  = start + horizon
            # Use step if None interval provided
            if interval is None:
                interval=self.case.step
            # Define the index. Make sure last point is included if
            # possible. If interval is not an exact divisor of stop,
            # the closest possible point under stop will be the end
            # point in order to keep interval unchanged among index.
            index = np.arange(start,stop+0.1,interval).astype(int)

        # Reindex to the desired index
        data_slice_reindexed = data_slice.reindex(index)

        for key in data_slice_reindexed.keys():
            # Use linear interpolation for continuous variables
            if key in self.categories['weather']:
                f = interpolate.interp1d(self.case.data.index,
                    self.case.data[key], kind='linear')
            # Use forward fill for discrete variables
            else:
                f = interpolate.interp1d(self.case.data.index,
                    self.case.data[key], kind='zero')
            data_slice_reindexed.loc[:,key] = f(index)

        if plot:
            if category is None:
                to_plot = data_slice_reindexed.keys()
            else:
                to_plot = self.categories[category]
            for var in to_plot:
                data_slice_reindexed[var].plot()
                plt.legend()
                plt.show()

        # Reset the index to keep the 'time' column in the data
        # Transform data frame to dictionary
        return data_slice_reindexed.reset_index().to_dict('list')

    def load_data_and_jsons(self):
        '''Load the data, kpis.json, and days.json from the resources folder of the fmu
        into the test case object.  The data is resampled according to the
        minimum sampling rate, where weather is linearly interpolated and
        schedules use a forward-fill.

        '''

        # Point to the fmu zip file
        z_fmu = zipfile.ZipFile(self.case.fmupath, 'r')
        # The following will work in any OS because the zip format
        # specifies a forward slash.

        # Load kpi json
        json_str = z_fmu.open('resources/kpis.json').read()
        self.case.kpi_json = json.loads(json_str)
        # Load days json
        json_str = z_fmu.open('resources/days.json').read()
        self.case.days_json = json.loads(json_str)
        # Load config json
        json_str = z_fmu.open('resources/config.json').read()
        self.case.config_json = json.loads(json_str)

        # Find the test case data files
        files = []
        for f in z_fmu.namelist():
            if f.startswith('resources/') and f.endswith('.csv'):
                files.append(f)

        # Find the minimum sampling resolution
        sampling = 3600.
        for f in files:
            df = pd.read_csv(z_fmu.open(f), comment='#')
            if 'time' in df.keys():
                new_sampling = df.iloc[1]['time']-df.iloc[0]['time']
                if new_sampling<sampling:
                    sampling=new_sampling

        # Define the index for one year with the minimum sampling found
        index = np.linspace(0.,3.1536e+7,int(3.1536e+7/sampling+1),dtype='int')

        # Get zone and boundary data keys allowed
        zon_keys, bou_keys = self._get_zone_and_boundary_keys()

        # Initialize test case data frame
        self.case.data = \
            pd.DataFrame(index=index).rename_axis('time')

        # Load the test case data
        for f in files:
            df = pd.read_csv(z_fmu.open(f))
            cols = df.keys()
            if 'time' in cols:
                for col in cols.drop('time'):
                    # Check that column has any of the allowed data keys
                    if not( (col in zon_keys) or (col in bou_keys) ):
                        raise KeyError('The data column {0} from file {1} of the fmu '\
                                       'does not match any of the allowed column keys and therefore '\
                                       'it cannot be loaded into the test case. Test case data '\
                                       'variables are used for forecasting and KPI calculation. If '\
                                       'you want this variable to be part of the test case data '\
                                       'make sure that the column has a key with any of the specified '\
                                       'formats in categories.json and that, if it is a zone related '\
                                       'key, it is in the format: variable[zone_identifier] '.format(col,f))
                    else:
                        for category in self.categories:
                            # Use linear interpolation for continuous variables
                            if any(col.startswith(key) for key in self.categories['weather']):
                                g = interpolate.interp1d(df['time'],df[col],
                                    kind='linear')
                                self.case.data.loc[:,col] = \
                                    g(self.case.data.index)
                            # Use forward fill for discrete variables
                            elif any(col.startswith(key) for key in self.categories[category]):
                                g = interpolate.interp1d(df['time'],df[col],
                                    kind='zero')
                                self.case.data.loc[:,col] = \
                                    g(self.case.data.index)
            else:
                warnings.warn('The following file does not have '\
                'time column and therefore no data is going to '\
                'be used from this file as test case data.', Warning)
                print(f)

        # Close the fmu
        z_fmu.close()

        # Convert any string formatted numbers to floats.
        self.case.data = self.case.data.applymap(float)


if __name__ == "__main__":
    import sys
    case_dir = os.path.join(\
        os.path.split(os.path.split(os.path.abspath(__file__))[0])[0],
        'testcase2')
    # Append the case directory to see the config file
    sys.path.append(case_dir)

    from testcase import TestCase
    case=TestCase()
    man = Data_Manager(case)
    data=man.get_data()