import os
import re
import sys
import numpy as np
import pandas as pd
from lib.utilities import codebook
from lib.utilities import serialize
from lib.experiment_specs import study_config


""" Class that contains functions that 
 - labels the values of certain categorical variables specified in lib.{experiment_name}_specs.value_labels.yaml
 - labels the variables of an expanded dataframe right before it becomes a stata file """

class Labeler:

    def __init__(self, codebook_dict: dict, sheet: str, is_wide: bool):
        self.label_codes = ["[PreviousSurvey]", "[Survey]", "[NextSurvey]", "[OldPhase]", "[NewPhase]"]
        self.is_wide = is_wide
        self.label_code_dic = Labeler._create_encode_dic()
        self.codebook = codebook_dict

        names = [x for x in study_config.surveys.keys()]
        codes = [study_config.surveys[x]["Code"] for x in study_config.surveys.keys()]
        self.code_survey_dic = dict(zip(codes, names))
        self.manual_var_df = pd.read_excel(codebook.manual_specs_path)


    """ creates a new first row in the dataframe which will contain the variable labels, as specified in the data\intermediate\mastercodebook"""
    def add_labels_to_df(self,df):
        df = df.reset_index(drop=True)
        df.index = df.index + 1
        df.loc[0] = ""
        df = df.sort_index()

        for col in df.columns:

            # don't expand label if col is a main column or if we don't want the codebook to have expanded labels
            if (col in study_config.main_cols+study_config.embedded_main_cols) or (self.is_wide == False):
                if col in self.codebook:
                    new_label = self.codebook[col]["VariableLabel"]

                else:
                    print(f"{col} not in codebook (main column) !!!")
                    new_label = col

            else:
                new_label = self._expand_label(col)

            df.loc[0, col] = new_label
        return df

    """ Expands the label for a given variable specified in the master codebook. Specifically:
     - if none of the label_codes are in the label, then a default expander is used
     - if a label_code is in the label, then they are substituted using the dictionary created in _create_encode_dic, also visualized in 
     lib.tempation_specs.label_code_dic.json """
    def _expand_label(self, variable):
        try:
            code, var = variable.split("_",1)
        except:
            print(f"Error extracting {variable} prefix")
            return variable

        survey = self.code_survey_dic[code]

        if var not in self.codebook:

            #if it's an intermediate variable or a text message survey variable, don't bother printing
            if ("_str" in var) or ("T" == var[0]):
                return variable
            else:
                print(f"{var} not in codebook!")
                return variable

        label = str(self.codebook[var]["VariableLabel"])
        prefix = str(self.codebook[var]["PrefixEncoding"])

        # if no manual specs, then no fancy labelling
        if var not in self.manual_var_df["VariableName"]:
            # if a survey variable
            if prefix == "Survey":
                new_label = survey + ": " + label

            # if a phase variable; i.e. the encoding is "NewPhase" or "OldPhase"
            else:
                try:
                    phase = study_config.surveys[survey][prefix]
                    phase_label = study_config.phases[phase]["Label"]
                    new_label = phase_label + ": " + label
                except:
                    print(
                        f"survey ({survey}) or phase label ({label}) not correctly specified in study config")
                    new_label = "BLAH"

        # fancy labelling
        else:
            for label_code in self.label_codes:
                if label_code in label:
                    label = label.replace(label_code,self.label_code_dic[survey][label_code])
            new_label = label

        return new_label

    """Creates a dictionary that will map macros in the compressed codebook to actual values in the expanded codebook. For example,
    if a label in the compressed codebook contains '[PreviousSurvey]', the label for M_MobileUseMinutes well end up containing 'Baseline' """
    @staticmethod
    def _create_encode_dic():
        label_code_dic = {}
        for phase, specs in study_config.phases.items():
            start_survey = specs["StartSurvey"]["Name"]

            old_phase = study_config.surveys[start_survey]["OldPhase"]
            new_phase = study_config.surveys[start_survey]["NewPhase"]
            survey = start_survey

            try:
                old_survey = study_config.phases[old_phase]["StartSurvey"]["Name"]
            except:
                old_survey = "Doesn't Exist"

            try:
                new_survey = study_config.phases[new_phase]["EndSurvey"]["Name"]
            except:
                new_survey = "Doesn't Exist"

            label_code_dic[survey] = {
                "[PreviousSurvey]": old_survey,
                "[Survey]": survey,
                "[NextSurvey]": new_survey,
                "[OldPhase]": old_phase,
                "[NewPhase]": new_phase
            }
        import json

        with open(os.path.join('lib','experiment_specs','label_code_dic.json'), 'w') as fp:
            json.dump(label_code_dic, fp)

        return label_code_dic


    """Encodes all values for variables listed in lib.experiment_specs.value_labels, and adds these value labels to codebook"""

    @staticmethod
    def label_values(df):
        label_dic = serialize.open_yaml(codebook.value_label_path)
        for encoding, chars in label_dic.items():
            if encoding == "Scale":
                for var_suffix in chars["VariableList"]:
                    for prefix in [x["Code"] for x in study_config.surveys.values()]:
                        var = prefix + "_" + var_suffix
                        if var in df.columns:
                            df[var] = df[var].astype(str).replace("nan", "")
                            df[f"{var}_num"] = df[var].apply(lambda x: re.sub("[^0-9]", "", x)).replace(" ", "")
                            df = df.rename(columns={var: var + "_str", var + "_num": var})
            else:
                for var_suffix in chars["VariableList"]:
                    for prefix in set([study_config.surveys[x]["Code"] for x in study_config.surveys.keys()]):
                        var = prefix + "_" + var_suffix
                        if var in df.columns:
                            try:
                                df[var] = df[var].astype(str).replace("nan", np.nan).replace("", np.nan)
                                df.loc[df[var].notnull(), var + "_num"] = df.loc[df[var].notnull(),
                                                                                 var].apply(
                                    lambda x: chars["ValueLabels"][x]).astype(float)
                                df = df.rename(columns={var: var + "_str", var + "_num": var})
                            except:
                                print(f"{var} was not properly encoded!")
        codebook.add_labels_to_codebook()
        return df