#!/usr/bin/env python3
"""
CONVERT_ANGATA_HARVEST.PY
=========================
Converts Angata harvest data from its received format to the standardized SmartCane format.

Input format (as received from Angata):
  Contract No | Field No | dop/doh
  0001        | 1        | 01/06/2023

Output format (SmartCane standard, matching Aura):
  field | sub_field | year | season_start | season_end | age | sub_area | tonnage_ha
  
The script:
1. Reads Angata harvest.xlsx
2. Extracts field numbers and dates
3. Creates field names from field numbers (e.g., "Field_1", "Field_2", etc.)
4. Extracts year from date
5. Uses dop/doh as season_start (other fields left as NaN for now)
6. Writes output to harvest.xlsx in SmartCane format

Usage:
  python convert_angata_harvest.py
"""

import pandas as pd
import os
from datetime import datetime
from pathlib import Path


def convert_angata_harvest():
    """Convert Angata harvest data to SmartCane format."""
    
    # Define paths
    angata_dir = Path("laravel_app/storage/app/angata/Data")
    input_file = angata_dir / "harvest.xlsx"
    output_file = angata_dir / "harvest.xlsx"
    
    # Read all sheets from input file
    print(f"Reading Angata harvest data from: {input_file}")
    xls = pd.ExcelFile(input_file)
    print(f"Sheet names found: {xls.sheet_names}")
    
    # Collect all data from all sheets
    all_data = []
    
    for sheet_name in xls.sheet_names:
        print(f"\nProcessing sheet: {sheet_name}")
        df = pd.read_excel(input_file, sheet_name=sheet_name)
        
        # Remove any completely empty rows
        df = df.dropna(how='all')
        
        # Skip if no data
        if len(df) == 0:
            print(f"  Sheet {sheet_name} is empty, skipping")
            continue
        
        # Check if this sheet has the required Field No column
        if 'Field No' not in df.columns:
            print(f"  Sheet {sheet_name} does not have 'Field No' column, skipping")
            continue
        
        # Check for date column (can be dop/doh or doh/dop)
        date_col = None
        if 'dop/doh' in df.columns:
            date_col = 'dop/doh'
        elif 'doh/dop' in df.columns:
            date_col = 'doh/dop'
        else:
            print(f"  Sheet {sheet_name} does not have date column (dop/doh or doh/dop), skipping")
            continue
        
        # Standardize date column name to 'dop/doh' for consistency
        df = df.rename(columns={date_col: 'dop/doh'})
        
        # Clean field numbers that may contain garbage
        df = df[pd.notna(df['Field No'])]
        
        print(f"  Loaded {len(df)} records from {sheet_name}")
        all_data.append(df)
    
    # Combine all sheets
    if not all_data:
        raise ValueError("No valid data found in any sheet")
    
    print(f"\nCombining data from {len(all_data)} sheets...")
    df = pd.concat(all_data, ignore_index=True)
    df = df.dropna(how='all')  # Remove empty rows after concat
    df = df[pd.notna(df['Field No'])]  # Ensure no NaN field numbers
    
    print(f"Total records after combining: {len(df)}")
    
    # Validate input columns
    required_cols = ['Field No', 'dop/doh']
    for col in required_cols:
        if col not in df.columns:
            raise ValueError(f"Missing required column: {col}")
    
    # Create conversion dataframe
    converted = pd.DataFrame()
    
    # Field name = field number as string (e.g., "1", "2", "10")
    converted['field'] = df['Field No'].astype(str)
    
    # Sub-field is same as field
    converted['sub_field'] = converted['field']
    
    # Parse dop/doh dates - format is DD/MM/YYYY
    print("\nParsing dates...")
    dates = []
    years = []
    for idx, date_str in enumerate(df['dop/doh']):
        try:
            # Handle NaN/null values
            if pd.isna(date_str):
                dates.append(pd.NaT)
                years.append(None)
            else:
                # Parse date string in DD/MM/YYYY format
                date_obj = pd.to_datetime(date_str, format='%d/%m/%Y')
                dates.append(date_obj)
                years.append(int(date_obj.year))
        except Exception as e:
            print(f"Warning: Could not parse date at row {idx}: {date_str} - {e}")
            dates.append(pd.NaT)
            years.append(None)
    
    # Ensure lists match DataFrame length (handle edge cases)
    assert len(dates) == len(df), f"Date list length {len(dates)} != DataFrame length {len(df)}"
    assert len(years) == len(df), f"Years list length {len(years)} != DataFrame length {len(df)}"
    
    converted['season_start'] = dates
    converted['year'] = years
    
    # Convert year to integer (handle NaN values)
    converted['year'] = converted['year'].apply(lambda x: int(x) if pd.notna(x) else None)
    
    # Other fields (not provided in Angata data)
    # season_end: empty string (to be filled in by other scripts)
    converted['season_end'] = ""
    # Replace NaN with None for age, sub_area, tonnage_ha
    converted['age'] = None
    converted['sub_area'] = None
    converted['tonnage_ha'] = None
    
    # Ensure year is integer type in DataFrame
    converted['year'] = converted['year'].astype('Int64')  # Nullable integer type
    
    # Reorder columns to match Aura format
    converted = converted[['field', 'sub_field', 'year', 'season_start', 'season_end', 'age', 'sub_area', 'tonnage_ha']]
    
    # Display summary
    print("\nConversion summary:")
    print(f"  Total records: {len(converted)}")
    print(f"  Date range: {converted['season_start'].min()} to {converted['season_start'].max()}")
    print(f"  Years: {sorted(converted['year'].dropna().unique())}")
    print(f"\nFirst 10 rows:")
    print(converted.head(10))
    
    # Save to Excel
    print(f"\nSaving converted data to: {output_file}")
    converted.to_excel(output_file, index=False, sheet_name='Harvest')
    print("Conversion complete!")
    
    return converted


if __name__ == "__main__":
    try:
        result = convert_angata_harvest()
        print("\nSuccess! Angata harvest data has been converted to SmartCane format.")
    except Exception as e:
        print(f"\nError during conversion: {e}")
        import traceback
        traceback.print_exc()