"""Shared JSON-RPC helpers for the standalone migration scripts in this
directory (migrate_members.py, migrate_students.py,
migrate_opening_balances.py, migrate_classroom.py).

Deliberately stdlib-only (no external dependencies) so these scripts can run
on any machine with Python 3, without needing the project's own virtualenv
or the Odoo MCP server - they talk to a deployed Odoo instance purely over
JSON-RPC.
"""
import csv
import json
import re
import urllib.request
from datetime import datetime


def jsonrpc_call(url, service, method, args):
    payload = {
        'jsonrpc': '2.0',
        'method': 'call',
        'params': {'service': service, 'method': method, 'args': args},
    }
    request = urllib.request.Request(
        f'{url}/jsonrpc',
        data=json.dumps(payload).encode('utf-8'),
        headers={'Content-Type': 'application/json'},
    )
    with urllib.request.urlopen(request) as response:
        result = json.loads(response.read())
    if 'error' in result:
        raise RuntimeError(result['error'].get('data', {}).get('message') or result['error'])
    return result['result']


def authenticate(url, db, username, password):
    uid = jsonrpc_call(url, 'common', 'authenticate', [db, username, password, {}])
    if not uid:
        raise RuntimeError('Authentication failed - check --url/--db/--username/--password')
    return uid


def execute_kw(url, db, uid, password, model, method, args, kwargs=None):
    full_args = [db, uid, password, model, method, args]
    if kwargs is not None:
        return jsonrpc_call(url, 'object', 'execute_kw', full_args + [kwargs])
    return jsonrpc_call(url, 'object', 'execute_kw', full_args)


def normalize_email(value):
    return (value or '').strip().lower() or None


def normalize_phone(value):
    value = (value or '').strip()
    if not value:
        return None
    keep_plus = value.startswith('+')
    digits = re.sub(r'\D', '', value)
    return ('+' if keep_plus else '') + digits


def normalize_date(value):
    """Parse a handful of common export date formats into ISO (YYYY-MM-DD)."""
    value = (value or '').strip()
    if not value:
        return None
    for fmt in ('%Y-%m-%d', '%m/%d/%Y', '%d/%m/%Y', '%Y/%m/%d', '%B %d, %Y', '%b %d, %Y'):
        try:
            return datetime.strptime(value, fmt).date().isoformat()
        except ValueError:
            continue
    return None


class MigrationReport:
    """Accumulates per-row outcomes and writes them to a report CSV."""

    def __init__(self):
        self.rows = []

    def add(self, key, action, reason=''):
        self.rows.append({'key': key, 'action': action, 'reason': reason})

    def write(self, path):
        with open(path, 'w', newline='', encoding='utf-8') as handle:
            writer = csv.DictWriter(handle, fieldnames=['key', 'action', 'reason'])
            writer.writeheader()
            writer.writerows(self.rows)

    def summary(self):
        counts = {}
        for row in self.rows:
            counts[row['action']] = counts.get(row['action'], 0) + 1
        return counts