"""
Shared helper utilities for the AI Marketing Automation app.
"""
import os
import pandas as pd
import numpy as np
import streamlit as st

# ── Paths ──────────────────────────────────────────────────────────────────────
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
LEADS_PATH = os.path.join(BASE_DIR, "Leads", "Leads.csv")
BANK_PATH  = os.path.join(BASE_DIR, "bank+marketing", "bank-full.csv")

# ── Loaders ────────────────────────────────────────────────────────────────────
@st.cache_data(show_spinner=False)
def load_leads() -> pd.DataFrame:
    df = pd.read_csv(LEADS_PATH)
    df.columns = df.columns.str.strip()
    return df

@st.cache_data(show_spinner=False)
def load_bank() -> pd.DataFrame:
    df = pd.read_csv(BANK_PATH, sep=";")
    df.columns = df.columns.str.strip()
    return df

# ── Common helpers ─────────────────────────────────────────────────────────────
def missing_summary(df: pd.DataFrame) -> pd.DataFrame:
    total   = df.isnull().sum()
    percent = (total / len(df) * 100).round(2)
    return pd.DataFrame({"Missing Count": total, "Missing %": percent})\
             .query("`Missing Count` > 0").sort_values("Missing %", ascending=False)

def dataset_info(df: pd.DataFrame) -> pd.DataFrame:
    info = pd.DataFrame({
        "Dtype":    df.dtypes.astype(str),
        "Non-Null": df.notnull().sum(),
        "Nulls":    df.isnull().sum(),
        "Unique":   df.nunique(),
    })
    return info

PHASE_DESCRIPTIONS = {
    1: ("Data Loading & Ingestion",      "Load, inspect, and profile both raw datasets."),
    2: ("Exploratory Data Analysis",     "Visualise distributions, correlations, and target balance."),
    3: ("Preprocessing & Feature Eng.",  "Clean, encode, engineer features, and handle imbalance."),
    4: ("Lead Scoring Models",           "Train LR, RF, XGBoost, LightGBM, SVM, and MLP models."),
    5: ("Model Evaluation & XAI",        "Compare models with ROC/PR curves, SHAP explainability."),
    6: ("NLP Analysis",                  "Sentiment, intent, and keyword analysis on text features."),
    7: ("AI Chatbot Lead Qualifier",     "Conversational chatbot for real-time lead qualification."),
    8: ("ROI Dashboard",                 "KPI metrics, lead funnel, and ROI calculator."),
}