#!/usr/bin/env python3
"""
Shared Claude Admin API Client - HTTP request handling with pagination.
"""

import json
import urllib.error
import urllib.parse
import urllib.request
from typing import Any


def fetch_api_data(endpoint: str, params: dict[str, Any], admin_key: str, debug: bool = False) -> dict[str, Any]:
    """
    Fetch data from Claude Admin API with automatic pagination.

    Args:
        endpoint: API endpoint path (e.g., '/v1/organizations/usage_report/messages')
        params: Query parameters
        admin_key: Admin API key (sk-ant-admin...)
        debug: Print debug messages for pagination (default: False)

    Returns:
        Complete API response with all paginated data merged

    Raises:
        Exception: If API request fails
    """
    base_url = 'https://api.anthropic.com'

    # Build query string
    query_parts = []
    for key, value in params.items():
        if isinstance(value, list):
            for item in value:
                query_parts.append(f'{urllib.parse.quote(key)}={urllib.parse.quote(str(item))}')
        else:
            query_parts.append(f'{urllib.parse.quote(key)}={urllib.parse.quote(str(value))}')

    query_string = '&'.join(query_parts)
    url = f'{base_url}{endpoint}?{query_string}'

    headers = {'anthropic-version': '2023-06-01', 'x-api-key': admin_key}

    all_data: dict[str, Any] | None = None
    page_num = 0

    while url:
        page_num += 1
        if debug:
            print(f'[DEBUG] Fetching page {page_num}: {url}')
        req = urllib.request.Request(url, headers=headers)

        try:
            with urllib.request.urlopen(req) as response:
                data = json.loads(response.read().decode())

                if all_data is None:
                    all_data = data
                    if debug:
                        items_count = len(data.get('data', []))
                        print(f'[DEBUG] Page {page_num}: Received {items_count} items (first page)')
                else:
                    # Merge paginated data
                    if 'data' in data:
                        page_items = len(data['data'])
                        all_data['data'].extend(data['data'])
                        total_items = len(all_data['data'])
                        if debug:
                            print(f'[DEBUG] Page {page_num}: Received {page_items} items, total accumulated: {total_items}')
                    all_data['has_more'] = data.get('has_more', False)
                    if 'next_page' in data:
                        all_data['next_page'] = data.get('next_page')
                    if 'last_id' in data:
                        all_data['last_id'] = data.get('last_id')

                # Check for next page - handle both pagination styles
                has_more = data.get('has_more', False)
                if debug:
                    print(f'[DEBUG] Page {page_num}: has_more={has_more}')

                if not has_more:
                    if debug:
                        print('[DEBUG] No more pages, pagination complete')
                    url = None
                elif data.get('next_page'):
                    # Messages endpoint uses next_page parameter
                    next_page = data['next_page']
                    base_url_only = url.split('?')[0] if '?' in url else url
                    separator = '&' if query_string else ''
                    url = f'{base_url_only}?{query_string}{separator}page={urllib.parse.quote(next_page)}'
                    if debug:
                        print(f'[DEBUG] Using next_page pagination: next_page={next_page}')
                elif data.get('last_id'):
                    # Users/API Keys endpoints use after_id with last_id cursor
                    last_id = data['last_id']
                    base_url_only = url.split('?')[0] if '?' in url else url
                    separator = '&' if query_string else ''
                    url = f'{base_url_only}?{query_string}{separator}after_id={urllib.parse.quote(last_id)}'
                    if debug:
                        print(f'[DEBUG] Using last_id pagination: last_id={last_id}')
                else:
                    if debug:
                        print('[DEBUG] No pagination cursor found (next_page or last_id), stopping')
                    url = None

        except urllib.error.HTTPError as e:
            error_body = e.read().decode() if e.fp else 'No error details'
            raise Exception(f'API Error {e.code}: {error_body}')

    if all_data is None:
        raise Exception('No data returned from API')

    if debug:
        total_items = len(all_data.get('data', []))
        print(f'[DEBUG] Pagination complete: {page_num} pages fetched, {total_items} total items')

    return all_data