# /home/Autopartes/pos/blueprints/catalog_bp.py
"""Catalog blueprint: browsable inventory with cart, external availability lookup,
and cross-reference queries."""

from flask import Blueprint, request, jsonify, g
from middleware import require_auth
from tenant_db import get_tenant_conn
from services.inventory_engine import get_stock_bulk

catalog_bp = Blueprint('catalog', __name__, url_prefix='/pos/api/catalog')


@catalog_bp.route('/search', methods=['GET'])
@require_auth('catalog.view')
def search_catalog():
    """Search the tenant's inventory as a catalog. Returns items with stock and pricing.

    Query params: q (search), category, brand, vehicle_brand, page, per_page

    NOTE on filtering:
    - `brand` filters by part manufacturer (Bosch, NGK, etc.) — the `brand` column.
    - `vehicle_brand` filters by vehicle compatibility (Toyota, Nissan, etc.) — searches
      inside the `vehicle_compatibility` JSON field via ILIKE on the cast text.
    """
    conn = get_tenant_conn(g.tenant_id)
    cur = conn.cursor()

    q = request.args.get('q', '')
    category = request.args.get('category', '')
    brand = request.args.get('brand', '')
    vehicle_brand = request.args.get('vehicle_brand', '')
    branch_id = request.args.get('branch_id', g.branch_id)
    in_stock_only = request.args.get('in_stock', '') == 'true'
    page = int(request.args.get('page', 1))
    per_page = min(int(request.args.get('per_page', 30)), 100)

    where = ["i.is_active = true"]
    params = []

    if branch_id:
        where.append("i.branch_id = %s")
        params.append(branch_id)
    if q:
        where.append("(i.part_number ILIKE %s OR i.name ILIKE %s OR i.barcode = %s)")
        params.extend([f'%{q}%', f'%{q}%', q])
    if category:
        where.append("i.category_id = %s")
        params.append(int(category))
    if brand:
        where.append("i.brand ILIKE %s")
        params.append(f'%{brand}%')
    if vehicle_brand:
        where.append("i.vehicle_compatibility::text ILIKE %s")
        params.append(f'%{vehicle_brand}%')

    where_sql = " AND ".join(where)

    cur.execute(f"SELECT count(*) FROM inventory i WHERE {where_sql}", params)
    total = cur.fetchone()[0]

    cur.execute(f"""
        SELECT i.id, i.part_number, i.barcode, i.name, i.brand, i.unit,
               i.price_1, i.price_2, i.price_3, i.tax_rate,
               i.image_url, i.category_id, i.location, i.min_stock
        FROM inventory i
        WHERE {where_sql}
        ORDER BY i.name
        LIMIT %s OFFSET %s
    """, params + [per_page, (page - 1) * per_page])

    rows = cur.fetchall()
    inv_ids = [r[0] for r in rows]

    # Bulk stock lookup
    stock_map = {}
    if inv_ids:
        cur.execute("""
            SELECT inventory_id, COALESCE(SUM(quantity), 0)
            FROM inventory_operations
            WHERE inventory_id = ANY(%s)
            GROUP BY inventory_id
        """, (inv_ids,))
        stock_map = {r[0]: r[1] for r in cur.fetchall()}

    items = []
    for r in rows:
        stock = stock_map.get(r[0], 0)
        if in_stock_only and stock <= 0:
            continue
        items.append({
            'id': r[0], 'part_number': r[1], 'barcode': r[2], 'name': r[3],
            'brand': r[4], 'unit': r[5],
            'price_1': float(r[6]) if r[6] else 0,
            'price_2': float(r[7]) if r[7] else 0,
            'price_3': float(r[8]) if r[8] else 0,
            'tax_rate': float(r[9]) if r[9] else 0.16,
            'image_url': r[10], 'category_id': r[11], 'location': r[12],
            'stock': stock,
            'low_stock': r[13] and stock < r[13] if r[13] else False
        })

    cur.close(); conn.close()

    total_pages = (total + per_page - 1) // per_page
    return jsonify({
        'data': items,
        'pagination': {'page': page, 'per_page': per_page, 'total': total, 'total_pages': total_pages}
    })


@catalog_bp.route('/categories', methods=['GET'])
@require_auth('catalog.view')
def catalog_categories():
    """Get categories with item counts for catalog navigation."""
    conn = get_tenant_conn(g.tenant_id)
    cur = conn.cursor()
    branch_id = request.args.get('branch_id', g.branch_id)

    where = "i.is_active = true"
    params = []
    if branch_id:
        where += " AND i.branch_id = %s"
        params.append(branch_id)

    cur.execute(f"""
        SELECT i.category_id, COUNT(*) as item_count
        FROM inventory i
        WHERE {where} AND i.category_id IS NOT NULL
        GROUP BY i.category_id
        ORDER BY item_count DESC
    """, params)
    categories = [{'id': r[0], 'count': r[1]} for r in cur.fetchall()]

    cur.close(); conn.close()
    return jsonify({'data': categories})


@catalog_bp.route('/brands', methods=['GET'])
@require_auth('catalog.view')
def catalog_brands():
    """Get part manufacturer brands with item counts for catalog navigation."""
    conn = get_tenant_conn(g.tenant_id)
    cur = conn.cursor()
    branch_id = request.args.get('branch_id', g.branch_id)

    where = "i.is_active = true"
    params = []
    if branch_id:
        where += " AND i.branch_id = %s"
        params.append(branch_id)

    cur.execute(f"""
        SELECT i.brand, COUNT(*) as item_count
        FROM inventory i
        WHERE {where} AND i.brand IS NOT NULL AND i.brand != ''
        GROUP BY i.brand
        ORDER BY item_count DESC
    """, params)
    brands = [{'name': r[0], 'count': r[1]} for r in cur.fetchall()]

    cur.close(); conn.close()
    return jsonify({'data': brands})


@catalog_bp.route('/barcode/<barcode>', methods=['GET'])
@require_auth('catalog.view')
def lookup_barcode(barcode):
    """Lookup a part by barcode (for scanner). Returns item with stock."""
    conn = get_tenant_conn(g.tenant_id)
    cur = conn.cursor()

    cur.execute("""
        SELECT i.id, i.part_number, i.barcode, i.name, i.brand, i.unit,
               i.price_1, i.price_2, i.price_3, i.tax_rate, i.cost,
               i.image_url, i.branch_id
        FROM inventory i
        WHERE (i.barcode = %s OR i.part_number = %s) AND i.is_active = true
        LIMIT 1
    """, (barcode, barcode))
    row = cur.fetchone()

    if not row:
        cur.close(); conn.close()
        return jsonify({'error': 'Part not found'}), 404

    from services.inventory_engine import get_stock
    item = {
        'id': row[0], 'part_number': row[1], 'barcode': row[2], 'name': row[3],
        'brand': row[4], 'unit': row[5],
        'price_1': float(row[6]) if row[6] else 0,
        'price_2': float(row[7]) if row[7] else 0,
        'price_3': float(row[8]) if row[8] else 0,
        'tax_rate': float(row[9]) if row[9] else 0.16,
        'cost': float(row[10]) if row[10] else 0,
        'image_url': row[11],
        'stock': get_stock(conn, row[0], row[12])
    }

    cur.close(); conn.close()
    return jsonify(item)


@catalog_bp.route('/external-availability/<part_number>', methods=['GET'])
@require_auth('catalog.view')
def external_availability(part_number):
    """Check part availability in external bodegas (Nexus marketplace).
    Requires internet. Calls the main Nexus API.
    """
    import requests

    try:
        # Query the Nexus master API for warehouse inventory
        # This calls the existing /api/search endpoint on the main Nexus server
        resp = requests.get(
            'http://localhost:5000/api/search',
            params={'q': part_number},
            timeout=5
        )
        if resp.status_code != 200:
            return jsonify({'data': [], 'source': 'nexus', 'error': 'Catalog unavailable'}), 200

        results = resp.json()
        return jsonify({'data': results.get('results', []), 'source': 'nexus'})

    except requests.RequestException:
        return jsonify({'data': [], 'source': 'nexus', 'error': 'No internet connection'}), 200


@catalog_bp.route('/cross-references/<part_number>', methods=['GET'])
@require_auth('catalog.view')
def cross_references(part_number):
    """Get OEM <-> aftermarket cross-references for a part number.

    Calls the Nexus master API which has the full cross-reference database
    (part_cross_references table). Returns OEM equivalents and aftermarket
    alternatives.

    This follows the same pattern as external-availability: the tenant POS
    calls the central Nexus server which holds the master catalog data.
    """
    import requests

    try:
        resp = requests.get(
            'http://localhost:5000/api/cross-references',
            params={'part_number': part_number},
            timeout=5
        )
        if resp.status_code != 200:
            return jsonify({'data': [], 'source': 'nexus', 'error': 'Cross-reference service unavailable'}), 200

        results = resp.json()
        return jsonify({
            'part_number': part_number,
            'cross_references': results.get('cross_references', []),
            'source': 'nexus'
        })

    except requests.RequestException:
        return jsonify({
            'part_number': part_number,
            'cross_references': [],
            'source': 'nexus',
            'error': 'No internet connection'
        }), 200