#!/usr/bin/env python3
"""
Import KNADIAN catalog from Excel into supplier_catalog tables.

Usage:
    python scripts/import_knadian_catalog.py
"""

import os
import re
import sys
from collections import defaultdict
from datetime import datetime

import psycopg2
from openpyxl import load_workbook

MASTER_DB_URL = os.environ.get('MASTER_DB_URL', 'postgresql://postgres@localhost/nexus_autoparts')
EXCEL_PATH = os.path.join(os.path.dirname(__file__), '..', 'data', 'KNADIAN.xlsx')
SUPPLIER_NAME = 'KNADIAN'
MAX_IMPORT_YEAR = datetime.now().year + 1  # reject future years from bad supplier data

MULTI_WORD_MAKES = {
    ('MERCEDES', 'BENZ'): 'MERCEDES BENZ',
    ('LAND', 'ROVER'): 'LAND ROVER',
    ('ALFA', 'ROMEO'): 'ALFA ROMEO',
    ('AMERICAN', 'MOTORS'): 'AMERICAN MOTORS',
    ('ROLLS', 'ROYCE'): 'ROLLS ROYCE',
    ('ASTON', 'MARTIN'): 'ASTON MARTIN',
    ('GREAT', 'WALL'): 'GREAT WALL',
}


def connect_master():
    return psycopg2.connect(MASTER_DB_URL)


def normalize_name(name):
    if not name:
        return ''
    return ' '.join(str(name).replace('\n', ' ').split())


def parse_year_token(token):
    """Parse a year token like '05', '1998', '2015'."""
    if not token or not re.match(r'^\d+$', str(token)):
        return None
    val = int(token)
    if 1000 <= val <= 2100:
        return val
    if 70 <= val <= 99:
        return 1900 + val
    if 0 <= val <= 69:
        return 2000 + val
    return None


def extract_years(text):
    """Extract year(s) from end of a string like '05/10', '2011', '1315', '97/99'."""
    if not text:
        return [None], ''
    s = str(text).strip()

    # Try trailing range with / or -: YY/YY, YYYY-YYYY, YY-YY
    m = re.search(r'\s+(\d{2,4})\s*[-/]\s*(\d{2,4})$', s)
    if m:
        start = parse_year_token(m.group(1))
        end = parse_year_token(m.group(2))
        if start and end:
            if end < start:
                start, end = end, start
            if end - start <= 100:
                rest = s[:m.start()].strip()
                return list(range(start, end + 1)), rest

    # Try trailing 4-digit year
    m = re.search(r'\s+(19|20)\d{2}$', s)
    if m:
        year = int(m.group(0).strip())
        rest = s[:m.start()].strip()
        return [year], rest

    # Try trailing 4 consecutive digits that look like a merged range: 1315 -> 2013,2014,2015
    m = re.search(r'\s+(\d{4})$', s)
    if m:
        digits = m.group(1)
        # If first two and last two are valid years, treat as range
        y1 = parse_year_token(digits[:2])
        y2 = parse_year_token(digits[2:])
        if y1 and y2 and y1 <= y2 and y2 - y1 <= 30:
            rest = s[:m.start()].strip()
            return list(range(y1, y2 + 1)), rest

    return [None], s


def parse_carro(carro):
    """Parse CARRO_PERTENECIENTE like 'ACURA TL 05/10' -> make, model, years."""
    if not carro:
        return {'make': None, 'model': None, 'years': [None], 'raw': carro}

    s = str(carro).strip()
    years, rest = extract_years(s)

    parts = rest.split()
    if not parts:
        return {'make': None, 'model': None, 'years': years, 'raw': s}

    # Extract make
    make = parts[0].upper()
    if len(parts) >= 2:
        key = (parts[0].upper(), parts[1].upper())
        if key in MULTI_WORD_MAKES:
            make = MULTI_WORD_MAKES[key]
            parts = parts[2:]
        else:
            parts = parts[1:]
    else:
        parts = parts[1:]

    model = ' '.join(parts) if parts else None

    return {
        'make': make,
        'model': model,
        'years': years,
        'raw': s,
    }


def extract_engine(name):
    """Extract engine description from NOMBRE_PIEZA like 'BOMBA_REFRIGERANTE L4 2.0'."""
    if not name:
        return None
    s = normalize_name(name)
    parts = s.split()
    if len(parts) <= 1:
        return None
    # Everything after first word
    engine = ' '.join(parts[1:])
    # Filter out meaningless tokens that should not be engines
    if engine.upper() in {'DEL.', 'TRAS.', 'FRONT.', 'EXT.', 'IZQ.', 'DER.', 'INF.', 'SUP.', 'TRANS.'}:
        return None
    return engine or None


def extract_interchanges(row):
    """Extract (brand, part_number) pairs from interchange columns.
    KNADIAN: interchanges start at col 3 (MARCA.1) through col 15 (INTERCAMBIO.5).
    """
    interchanges = []
    for i in range(6):
        marca_col = 3 + i * 2
        inter_col = 4 + i * 2
        if marca_col < len(row) and row[marca_col]:
            brand = str(row[marca_col]).strip()
            pn = str(row[inter_col]).strip() if inter_col < len(row) and row[inter_col] else ''
            if brand and pn:
                interchanges.append((brand, pn))
    return interchanges


def main():
    print(f"[{datetime.now().isoformat()}] Starting KNADIAN import...")

    if not os.path.exists(EXCEL_PATH):
        print(f"ERROR: Excel not found at {EXCEL_PATH}")
        sys.exit(1)

    print(f"Loading {EXCEL_PATH}...")
    wb = load_workbook(EXCEL_PATH, read_only=True, data_only=True)

    master_conn = connect_master()
    master_cur = master_conn.cursor()

    upsert_catalog_sql = """
        INSERT INTO supplier_catalog (supplier_name, sku, name, category, is_active)
        VALUES (%s, %s, %s, %s, true)
        ON CONFLICT (supplier_name, sku, category) DO UPDATE SET
            name = EXCLUDED.name,
            category = EXCLUDED.category,
            is_active = true
        RETURNING id
    """

    insert_compat_sql = """
        INSERT INTO supplier_catalog_compat
            (catalog_id, make, model, year, engine, model_year_engine_id, source)
        VALUES (%s, %s, %s, %s, %s, NULL, %s)
        ON CONFLICT (catalog_id, make, model, year, engine) DO NOTHING
    """

    insert_interchange_sql = """
        INSERT INTO supplier_catalog_interchange (catalog_id, brand, part_number)
        VALUES (%s, %s, %s)
        ON CONFLICT DO NOTHING
    """

    stats = defaultdict(int)

    for sheet_name in wb.sheetnames:
        ws = wb[sheet_name]
        rows = list(ws.iter_rows(values_only=True))
        if not rows:
            continue
        data_rows = rows[1:]
        stats['sheets'] += 1
        print(f"\nProcessing sheet '{sheet_name}' with {len(data_rows)} rows...")

        catalog_id_cache = {}

        for idx, row in enumerate(data_rows):
            if idx % 2000 == 0 and idx > 0:
                print(f"  ...{idx} rows processed")

            if not row or len(row) < 3 or not row[2]:
                stats['skipped_no_sku'] += 1
                continue

            make_col = str(row[0]).strip().upper() if row[0] else ''
            model_col = str(row[1]).strip() if row[1] else ''
            sku = str(row[2]).strip()
            name = normalize_name(row[15]) if len(row) > 15 and row[15] else sheet_name
            carro = str(row[16]).strip() if len(row) > 16 and row[16] else ''

            if not sku:
                stats['skipped_no_sku'] += 1
                continue

            # Always try to parse year from CARRO_PERTENECIENTE
            parsed = parse_carro(carro)
            years = parsed['years']

            # Prefer explicit make/model columns; fallback to parsed carro
            if make_col:
                make = make_col
            else:
                make = parsed['make']

            if model_col:
                model = model_col
            else:
                model = parsed['model']

            # If year still missing, maybe the model column itself contains a year
            if years == [None] and model_col:
                years, _ = extract_years(model_col)

            if not make or not model:
                stats['skipped_no_vehicle'] += 1
                continue

            # Filter out future years and de-duplicate
            filtered_years = []
            for y in years:
                if y is None:
                    if None not in filtered_years:
                        filtered_years.append(None)
                elif y <= MAX_IMPORT_YEAR:
                    if y not in filtered_years:
                        filtered_years.append(y)
            years = filtered_years if filtered_years else [None]

            stats['rows'] += 1

            # Upsert catalog item (keyed by sku)
            cache_key = sku
            catalog_id = catalog_id_cache.get(cache_key)
            if catalog_id is None:
                master_cur.execute(upsert_catalog_sql, (SUPPLIER_NAME, sku, name, sheet_name))
                row_result = master_cur.fetchone()
                catalog_id = row_result[0] if row_result else None
                catalog_id_cache[cache_key] = catalog_id
                stats['catalog_items'] += 1

            if catalog_id is None:
                stats['skipped_no_catalog'] += 1
                continue

            engine = extract_engine(name)

            for year in years:
                master_cur.execute(insert_compat_sql, (
                    catalog_id,
                    make,
                    model,
                    year,
                    engine,
                    'import_text',
                ))
                stats['compat_rows'] += 1

            interchanges = extract_interchanges(row)
            for brand, pn in interchanges:
                master_cur.execute(insert_interchange_sql, (catalog_id, brand, pn))
                stats['interchange_rows'] += 1

        master_conn.commit()
        print(f"  Sheet '{sheet_name}' committed.")

    print(f"\n{'='*60}")
    print("IMPORT COMPLETE")
    print(f"{'='*60}")
    for k, v in sorted(stats.items()):
        print(f"{k:25s}: {v}")

    master_cur.close()
    master_conn.close()


if __name__ == '__main__':
    main()