from datetime import datetime, timezone
from flask import Blueprint, request, jsonify, current_app
from functools import wraps

sync_bp = Blueprint('sync', __name__)

def require_sync_secret(f):
    @wraps(f)
    def decorated(*args, **kwargs):
        secret = current_app.config.get('SYNC_SECRET', '')
        if secret and request.headers.get('X-Sync-Secret') != secret:
            return jsonify({"error": "unauthorized"}), 401
        return f(*args, **kwargs)
    return decorated

@sync_bp.route('/api/ping')
def ping():
    return jsonify({"status": "ok"}), 200

@sync_bp.route('/api/sync/push', methods=['POST'])
@require_sync_secret
def sync_push():
    data = request.get_json()
    if not data:
        return jsonify({"error": "empty payload"}), 400

    instance_id = data.get('instance_id', 'unknown')
    synced_at = data.get('synced_at') or datetime.now(timezone.utc).isoformat()

    from core.db import get_db_connection

    with get_db_connection() as conn:
        # 1. Deletions
        for d in data.get('deletions', []):
            et = d['entity_type']
            eu = d['entity_uuid']
            # Log to server's sync_deletions so other pulling clients see it
            existing = conn.execute(
                "SELECT id FROM sync_deletions WHERE entity_type = ? AND entity_uuid = ?",
                (et, eu)
            ).fetchone()
            if not existing:
                conn.execute(
                    "INSERT INTO sync_deletions (entity_type, entity_uuid, deleted_at) VALUES (?, ?, ?)",
                    (et, eu, synced_at)
                )
            if et == 'debtor':
                conn.execute("DELETE FROM debtors WHERE uuid = ?", (eu,))
            elif et == 'ticket':
                conn.execute("DELETE FROM debtor_tickets WHERE uuid = ?", (eu,))
            elif et == 'dicom':
                conn.execute("DELETE FROM dicom WHERE uuid = ?", (eu,))
            elif et == 'expense':
                conn.execute("DELETE FROM expenses WHERE uuid = ?", (eu,))
            elif et == 'sale':
                conn.execute("DELETE FROM sales WHERE uuid = ?", (eu,))
            elif et == 'product':
                conn.execute("DELETE FROM products WHERE barcode = ?", (eu,))

        # 2. Sales
        for sale in data.get('sales', []):
            existing = conn.execute(
                "SELECT id FROM sales WHERE uuid = ?", (sale['uuid'],)
            ).fetchone()
            if existing:
                continue
            cur = conn.execute(
                "INSERT INTO sales (date, total, payment_method, uuid, synced_at) VALUES (?, ?, ?, ?, ?)",
                (sale.get('date', synced_at), sale['total'], sale.get('payment_method', 'efectivo'),
                 sale['uuid'], synced_at)
            )
            sale_id = cur.lastrowid
            for item in sale.get('items', []):
                conn.execute(
                    "INSERT INTO sale_items (sale_id, barcode, name, price, quantity, subtotal) VALUES (?, ?, ?, ?, ?, ?)",
                    (sale_id, item['barcode'], item['name'], item.get('price', 0),
                     item.get('qty', 1), item.get('subtotal', 0))
                )

        # 3. Products
        now = datetime.now(timezone.utc).isoformat()
        for p in data.get('products', []):
            existing = conn.execute(
                "SELECT updated_at FROM products WHERE barcode = ?", (p['barcode'],)
            ).fetchone()
            if existing and existing[0] >= p.get('updated_at', now):
                continue
            conn.execute('''INSERT INTO products (barcode, name, price, image_url, stock, unit_type, updated_at, updated_by)
                            VALUES (?,?,?,?,?,?,?,?)
                            ON CONFLICT(barcode) DO UPDATE SET
                            name=excluded.name, price=excluded.price,
                            image_url=excluded.image_url, stock=excluded.stock,
                            unit_type=excluded.unit_type, updated_at=excluded.updated_at,
                            updated_by=excluded.updated_by''',
                         (p['barcode'], p.get('name', ''), p.get('price', 0),
                          p.get('image_url'), p.get('stock', 0), p.get('unit_type', 'unit'),
                          p.get('updated_at', now), instance_id))

        # 4. Debtors
        for d in data.get('debtors', []):
            conn.execute('''INSERT INTO debtors (uuid, name, contact_info, updated_at, updated_by)
                            VALUES (?,?,?,?,?)
                            ON CONFLICT(uuid) DO UPDATE SET
                            name=excluded.name, contact_info=excluded.contact_info,
                            updated_at=excluded.updated_at, updated_by=excluded.updated_by''',
                         (d['uuid'], d['name'], d.get('contact_info', ''),
                          d.get('updated_at', now), d.get('updated_by', instance_id)))

        # 5. Dicom (legacy)
        for d in data.get('dicom', []):
            conn.execute('''INSERT INTO dicom (uuid, name, amount, notes, image_url, updated_at, updated_by)
                            VALUES (?,?,?,?,?,?,?)
                            ON CONFLICT(uuid) DO UPDATE SET
                            name=excluded.name, amount=excluded.amount,
                            notes=excluded.notes, image_url=excluded.image_url,
                            updated_at=excluded.updated_at, updated_by=excluded.updated_by''',
                         (d['uuid'], d['name'], d.get('amount', 0), d.get('notes', ''),
                          d.get('image_url', ''), d.get('updated_at', now), d.get('updated_by', instance_id)))

        # 6. Debtor tickets with items
        for t in data.get('tickets', []):
            existing = conn.execute(
                "SELECT id FROM debtor_tickets WHERE uuid = ?", (t['uuid'],)
            ).fetchone()
            if existing:
                continue
            debtor_row = conn.execute(
                "SELECT id FROM debtors WHERE uuid = ?", (t['debtor_uuid'],)
            ).fetchone()
            if not debtor_row:
                continue
            cur = conn.execute(
                "INSERT INTO debtor_tickets (uuid, debtor_id, date, total, amount_paid, status, updated_at, updated_by) VALUES (?,?,?,?,?,?,?,?)",
                (t['uuid'], debtor_row[0], t.get('date', synced_at), t['total'],
                 t.get('amount_paid', 0), t.get('status', 'unpaid'),
                 t.get('updated_at', now), t.get('updated_by', instance_id))
            )
            ticket_id = cur.lastrowid
            for item in t.get('items', []):
                conn.execute(
                    "INSERT INTO debtor_ticket_items (ticket_id, barcode, name, price, quantity, subtotal) VALUES (?,?,?,?,?,?)",
                    (ticket_id, item['barcode'], item['name'], item.get('price', 0),
                     item.get('qty', 1), item.get('subtotal', 0))
                )

        # 7. Expenses
        for e in data.get('expenses', []):
            existing = conn.execute(
                "SELECT id FROM expenses WHERE uuid = ?", (e['uuid'],)
            ).fetchone()
            if existing:
                continue
            conn.execute(
                "INSERT INTO expenses (uuid, date, description, amount) VALUES (?,?,?,?)",
                (e['uuid'], e.get('date', synced_at), e['description'], e['amount'])
            )

        conn.commit()

    return jsonify({"status": "ok", "instance_id": instance_id}), 200

@sync_bp.route('/api/sync/pull')
@require_sync_secret
def sync_pull():
    since = request.args.get('since', '1970-01-01')
    since_sales = request.args.get('since_sales', '1970-01-01')
    since_debtors = request.args.get('since_debtors', '1970-01-01')
    since_tickets = request.args.get('since_tickets', '1970-01-01')
    since_dicom = request.args.get('since_dicom', '1970-01-01')
    since_expenses = request.args.get('since_expenses', '1970-01-01')
    since_deletions = request.args.get('since_deletions', '1970-01-01')

    from core.db import get_db_connection
    with get_db_connection() as conn:
        # Products
        products = conn.execute(
            "SELECT barcode, name, price, image_url, stock, unit_type, updated_at, updated_by FROM products WHERE updated_at >= ?",
            (since,)
        ).fetchall()

        # Sales with items
        sales_rows = conn.execute(
            "SELECT id, uuid, date, total, payment_method FROM sales WHERE date >= ? ORDER BY date",
            (since_sales,)
        ).fetchall()
        sales_payload = []
        for s in sales_rows:
            items = conn.execute(
                "SELECT barcode, name, price, quantity, subtotal FROM sale_items WHERE sale_id = ?",
                (s[0],)
            ).fetchall()
            sales_payload.append({
                "uuid": s[1], "date": s[2], "total": s[3], "payment_method": s[4],
                "items": [{"barcode": i[0], "name": i[1], "price": i[2], "qty": i[3], "subtotal": i[4]} for i in items]
            })

        # Debtors
        debtors = conn.execute(
            "SELECT uuid, name, contact_info, updated_at, updated_by FROM debtors WHERE updated_at >= ?",
            (since_debtors,)
        ).fetchall()

        # Dicom (legacy)
        dicom_rows = conn.execute(
            "SELECT uuid, name, amount, notes, image_url, updated_at, updated_by FROM dicom WHERE updated_at >= ?",
            (since_dicom,)
        ).fetchall()

        # Debtor tickets with items
        tickets = conn.execute(
            "SELECT id, uuid, debtor_id, date, total, amount_paid, status, updated_at, updated_by FROM debtor_tickets WHERE updated_at >= ?",
            (since_tickets,)
        ).fetchall()
        ticket_payload = []
        for t in tickets:
            ticket_id, ticket_uuid, debtor_id = t[0], t[1], t[2]
            debtor_uuid = conn.execute("SELECT uuid FROM debtors WHERE id = ?", (debtor_id,)).fetchone()
            items = conn.execute(
                "SELECT barcode, name, price, quantity, subtotal FROM debtor_ticket_items WHERE ticket_id = ?",
                (ticket_id,)
            ).fetchall()
            ticket_payload.append({
                "uuid": ticket_uuid, "debtor_uuid": debtor_uuid[0] if debtor_uuid else '',
                "date": t[3], "total": t[4], "amount_paid": t[5], "status": t[6],
                "updated_at": t[7], "updated_by": t[8],
                "items": [{"barcode": i[0], "name": i[1], "price": i[2], "qty": i[3], "subtotal": i[4]} for i in items]
            })

        # Expenses
        expenses = conn.execute(
            "SELECT uuid, date, description, amount FROM expenses WHERE date >= ?",
            (since_expenses,)
        ).fetchall()

        # Deletions
        deletions = conn.execute(
            "SELECT entity_type, entity_uuid, deleted_at FROM sync_deletions WHERE deleted_at >= ?",
            (since_deletions,)
        ).fetchall()

    return jsonify({
        "products": [
            {"barcode": p[0], "name": p[1], "price": p[2], "image_url": p[3],
             "stock": p[4], "unit_type": p[5], "updated_at": p[6], "updated_by": p[7]}
            for p in products
        ],
        "sales": sales_payload,
        "debtors": [
            {"uuid": d[0], "name": d[1], "contact_info": d[2], "updated_at": d[3], "updated_by": d[4]}
            for d in debtors
        ],
        "dicom": [
            {"uuid": d[0], "name": d[1], "amount": d[2], "notes": d[3], "image_url": d[4],
             "updated_at": d[5], "updated_by": d[6]}
            for d in dicom_rows
        ],
        "tickets": ticket_payload,
        "expenses": [
            {"uuid": e[0], "date": e[1], "description": e[2], "amount": e[3]}
            for e in expenses
        ],
        "deletions": [
            {"entity_type": d[0], "entity_uuid": d[1], "deleted_at": d[2]}
            for d in deletions
        ]
    }), 200