"""
This class create a connection to Snowflake, run queries (read and write)
"""
import json

import numpy as np
import pandas as pd
from snowflake.snowpark import Session
from sympy.strategies.branch import condition


class SnowFlakeConn:
    def __init__(self, session, brand):
        self. session = session
        self.brand = brand

        self.final_columns = ['user_id', "email", "user_info", "permission", "expiration_date", "recsys_result", "message", "brand", "recommendation", "segment_name", "timestamp"]

        self.campaign_id = {
            "singeo": 460,
            "pianote": 457,
            "guitareo": 458,
            "drumeo": 392
        }

    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def run_read_query(self, query, data):
        """
        Executes a SQL query on Snowflake that fetch the data
        :return: Pandas dataframe containing the query results
        """

        # Connect to Snowflake
        try:
            dataframe = self.session.sql(query).to_pandas()
            dataframe.columns = dataframe.columns.str.lower()
            print(f"reading {data} table successfully")
            return dataframe
        except Exception as e:
            print(f"Error in creating/updating table: {e}")

    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def is_json_parsed_to_collection(self, s):
        try:
            parsed = json.loads(s)
            return isinstance(parsed, (dict, list))
        except:
            return False
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def store_df_to_snowflake(self, table_name, dataframe, database="ONLINE_RECSYS", schema="GENERATED_DATA"):
        """
        Executes a SQL query on Snowflake that write the preprocessed data on new tables
        :param query: SQL query string to be executed
        :return: None
        """

        try:
            self.session.use_database(database)
            self.session.use_schema(schema)

            dataframe = dataframe.reset_index(drop=True)
            dataframe.columns = dataframe.columns.str.upper()

            self.session.write_pandas(df=dataframe,
                                      table_name=table_name.strip().upper(),
                                      auto_create_table=True,
                                      overwrite=True,
                                      use_logical_type=True)
            print(f"Data inserted into {table_name} successfully.")

        except Exception as e:
            print(f"Error in creating/updating/inserting table: {e}")

    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def get_data(self, data, list_of_ids=None):
        """
        valid Data is = {users, contents, interactions, recsys, popular_contents}
        :param data:
        :return:
        """
        valid_data = {'users', 'contents', 'interactions', 'recsys', 'popular_contents'}

        if data not in valid_data:
            raise ValueError(f"Invalid data type: {data}")

        # Construct the method name based on the input
        method_name = f"_get_{data}"

        # Retrieve the method dynamically
        method = getattr(self, method_name, None)
        if method is None:
            raise NotImplementedError(f"The method {method_name} is not implemented.")

        query = method(list_of_ids)
        data = self.run_read_query(query, data)

        return data
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def _get_contents(self, list_of_ids=None):
        query = f"""
        select CONTENT_ID, CONTENT_TYPE, CONTENT_PROFILE as content_info --, CONTENT_PROFILE_VECTOR
        from ONLINE_RECSYS.VECTOR_DB.VECTORIZED_CONTENT
        where BRAND = '{self.brand}'        
        """
        return query
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def _get_users(self, list_of_ids=None):

        if list_of_ids is not None:
            ids_str = "(" + ", ".join(map(str, list_of_ids)) + ")"
            condition = f"AND USER_ID in {ids_str}"
        else :
            condition = ""

        query = f"""
        select USER_ID, BRAND, FIRST_NAME, BIRTHDAY, TIMEZONE, EMAIL, CURRENT_TIMESTAMP() AS TIMESTAMP, DIFFICULTY, SELF_REPORT_DIFFICULTY, USER_PROFILE as user_info, PERMISSION, EXPIRATION_DATE,
        DATEDIFF(
        day,
        CURRENT_DATE(),
        CASE 
            WHEN DATE_FROM_PARTS(YEAR(CURRENT_DATE()), EXTRACT(MONTH FROM BIRTHDAY), EXTRACT(DAY FROM BIRTHDAY)) < CURRENT_DATE() 
            THEN DATE_FROM_PARTS(YEAR(CURRENT_DATE()) + 1, EXTRACT(MONTH FROM BIRTHDAY), EXTRACT(DAY FROM BIRTHDAY))
            ELSE DATE_FROM_PARTS(YEAR(CURRENT_DATE()), EXTRACT(MONTH FROM BIRTHDAY), EXTRACT(DAY FROM BIRTHDAY))
        END) AS birthday_reminder
        from ONLINE_RECSYS.PREPROCESSED.USERS
        where BRAND = '{self.brand}' {condition}    
        """
        return query
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def _get_interactions(self, list_of_ids=None):

        if list_of_ids is not None:
            ids_str = "(" + ", ".join(map(str, list_of_ids)) + ")"
            condition = f"AND USER_ID in {ids_str}"
        else :
            condition = ""

        query = f"""
        WITH latest_interactions AS(
         SELECT
            USER_ID, CONTENT_ID, CONTENT_TYPE, EVENT_TEXT, TIMESTAMP,
            ROW_NUMBER() OVER(PARTITION BY USER_ID ORDER BY TIMESTAMP DESC) AS rn
         FROM ONLINE_RECSYS.PREPROCESSED.RECSYS_INTEACTIONS
         WHERE BRAND = '{self.brand}' AND EVENT_TEXT IN('Video Completed', 'Video Playing') {condition})
        
        SELECT i.USER_ID, i.CONTENT_ID, i.CONTENT_TYPE, c.content_profile as last_completed_content, i.EVENT_TEXT, i.TIMESTAMP, DATEDIFF('week', i.TIMESTAMP, CURRENT_TIMESTAMP) AS weeks_since_last_interaction
        FROM latest_interactions i
        LEFT JOIN 
            ONLINE_RECSYS.VECTOR_DB.VECTORIZED_CONTENT c ON c.CONTENT_ID = i.CONTENT_ID
        WHERE rn = 1;
        """
        return query
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def _get_recsys(self, list_of_ids=None):

        if list_of_ids is not None:
            ids_str = "(" + ", ".join(map(str, list_of_ids)) + ")"
            condition = f"WHERE USER_ID in {ids_str}"
        else :
            condition = ""

        recsys_col = f"{self.brand}_recsys_v3"
        query = f"""
        select USER_ID, {recsys_col} as recsys_result
        from RECSYS_V3.RECSYS_CIO.RECSYS_V3_CUSTOMER_IO_OLD  
        {condition}
        """
        return query
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def _get_popular_contents(self, list_of_ids=None):

        query = f"""
        select POPULAR_CONTENT
        from RECSYS_V3.RECSYS_CIO.POPULAR_CONTENT_CUSTOMER_IO_OLD
        where brand = '{self.brand.lower()}'    
        """

        return query
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def extract_id_from_email(self, emails):
        """
        extracting user_ids from emails
        :param unique_emails:
        :return:
        """

        email_list_str = ', '.join(f"'{email}'" for email in emails)
        query = f"""
        SELECT id as USER_ID, email as EMAIL
        FROM STITCH.MUSORA_ECOM_DB.USORA_USERS
        WHERE email IN ({email_list_str})
        """

        user_ids_df = self.run_read_query(query, data="User_ids")
        return user_ids_df
    # ---------------------------------------------------------------
    # ---------------------------------------------------------------

    def adjust_dataframe(self, dataframe):
        """
        Filter dataframe to only include the columns in self.final_columns.
        Add any missing columns with None values.
        Ensure the final order is consistent with self.final_columns.
        """
        # Work with a copy so that we don't modify the original input
        final_df = dataframe.copy()

        # Normalize column names to lower-case for matching (if needed)
        final_df.columns = final_df.columns.str.lower()
        expected_cols = [col.lower() for col in self.final_columns]

        # Keep only those columns in the expected list
        available = [col for col in final_df.columns if col in expected_cols]
        final_df = final_df[available]

        # Add missing columns with None values
        for col in expected_cols:
            if col not in final_df.columns:
                final_df[col] = None

        # Reorder the columns to the desired order
        final_df = final_df[expected_cols]

        # If you need the column names to match exactly what self.final_columns provides (case-sensitive),
        # you can rename them accordingly.
        rename_mapping = {col.lower(): col for col in self.final_columns}
        final_df.rename(columns=rename_mapping, inplace=True)

        return final_df

    # ---------------------------------------------------------------
    # ---------------------------------------------------------------
    def close_connection(self):
        self.session.close()

    def get_inactive_users_by_brand(self, brand):
        if brand == "singeo":
            return self.get_users_in_campaign(brand=brand)
        else:
            return self._get_inactive_users(brand=brand)

    # ===============================================================
    def get_users_in_campaign(self, brand, campaign_name="Singeo - Inactive Members (for 3 days) - Re-engagement", stage=1, campaign_view='singeo_re_engagement'):
        """
        creating a query to fetch requested users
        :param campaign_view:
        :param stage:
        :param campaign_name:
        :param brand:
        :return:
        """
        # camp_id = self.campaign_id[brand]

        if stage == 1:
            query = f"""
WITH eligible_users AS (
  SELECT
      s.USER_ID,
      s.EMAIL,
      s.BRAND,
      s.CAMPAIGN_NAME
  FROM MESSAGING_SYSTEM.CAMPAIGNS.{campaign_view} s
  WHERE s.CAMPAIGN_NAME = '{campaign_name}'
    AND s.BRAND = '{brand}'
),
msgs AS (
  -- Only messages from the same brand/campaign
  SELECT
      m.EMAIL,
      m.BRAND,
      m.CAMPAIGN_NAME,
      m.STAGE,
      m.TIMESTAMP
  FROM MESSAGING_SYSTEM.GENERATED_DATA.INITIAL_MESSAGES m
  WHERE m.CAMPAIGN_NAME = '{campaign_name}'
    AND m.BRAND = '{brand}'
),
no_stage1 AS (
  -- Users who do not already have stage 1
  SELECT e.*
  FROM eligible_users e
  LEFT JOIN msgs m1
    ON m1.EMAIL = e.EMAIL
   AND m1.STAGE = 1
  WHERE m1.EMAIL IS NULL
)
SELECT
    n.EMAIL,
FROM no_stage1 n
;
"""

        else:
            query = f"""
WITH eligible_users AS (
  SELECT
      s.USER_ID,
      s.EMAIL,
      s.BRAND,
      s.CAMPAIGN_NAME
  FROM MESSAGING_SYSTEM.CAMPAIGNS.{campaign_view} s
  WHERE s.CAMPAIGN_NAME = '{campaign_name}'
    AND s.BRAND = '{brand}'
),
msgs AS (
  -- Only messages from the same brand/campaign
  SELECT
      m.EMAIL,
      m.BRAND,
      m.CAMPAIGN_NAME,
      m.STAGE,
      m.TIMESTAMP
  FROM MESSAGING_SYSTEM.GENERATED_DATA.INITIAL_MESSAGES m
  WHERE m.CAMPAIGN_NAME = '{campaign_name}'
    AND m.BRAND = '{brand}'
),
has_prev AS (
  -- Users who have the immediately previous stage (N-1)
  SELECT e.*
  FROM eligible_users e
  JOIN msgs mp
    ON mp.EMAIL = e.EMAIL
   AND mp.STAGE = {stage} - 1
),
no_current_stage AS (
  -- Exclude users who already have the current stage (N)
  SELECT e.*
  FROM has_prev e
  LEFT JOIN msgs mn
    ON mn.EMAIL = e.EMAIL
   AND mn.STAGE = {stage}
  WHERE mn.EMAIL IS NULL
),
latest_msg AS (
  -- Most-recent message timestamp per user (within this brand/campaign)
  SELECT
      EMAIL,
      MAX(TIMESTAMP) AS LAST_TS
  FROM msgs
  GROUP BY EMAIL
)
SELECT
    n.EMAIL,
FROM no_current_stage n
JOIN latest_msg l
  ON l.EMAIL = n.EMAIL
-- Ensure no messages for this user in this brand/campaign in the last 36 hours
--WHERE l.LAST_TS < DATEADD(HOUR, -36, CURRENT_TIMESTAMP())
;
            """

        users_df = self.run_read_query(query, data=f"{brand}_campaign")
        return users_df

    def _get_inactive_users(self, brand: str):
        """
        Return up to 50 USER_IDs in the requested brand whose last interaction is > 5 days ago,
        restricted to users that exist in ONLINE_RECSYS.PREPROCESSED.USERS.
        """

        path = f"Data/{brand.lower()}_test.csv"
        users_df = pd.read_csv(path)
        return users_df