/******************************************************************************
 * Copyright (c) 2026 Contributors to the Eclipse Foundation.
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * https://www.eclipse.org/legal/epl-2.0.
 *
 * SPDX-License-Identifier: EPL-2.0
 *****************************************************************************/

import { FC, useContext, useMemo } from 'react';
import { Box, Alert } from '@mui/material';
import { useParams, useNavigate } from 'react-router';
import { MainContext } from '../../../context';
import type { Customer } from '../../../extension-registry-types';
import { handleError } from '../../../utils';
import { AdminDashboardRoutes } from '../admin-dashboard-routes';
import { SearchListContainer } from '../search-list-container';
import { CustomerSearch } from './usage-stats-search';
import { UsageStatsChart } from '../../../components/rate-limiting/usage-stats/usage-stats-chart';
import { useAdminUsageStats } from './use-usage-stats';
import { useCustomers } from '../customers/use-customers';

export const UsageStatsView: FC = () => {
    const { customer } = useParams<{ customer: string }>();
    const navigate = useNavigate();
    const { pageSettings } = useContext(MainContext);

    const { data: customersData, isFetching: customersLoading, error: customersErrorObj } = useCustomers();
    const customers = customersData?.customers ?? [];
    const customersError = customersErrorObj ? handleError(customersErrorObj as Error) : null;

    const { usageStats, dailyP95, loading, error: statsError, startDate, setStartDate } = useAdminUsageStats(customer);

    const selectedCustomer = useMemo(() => customers.find(c => c.name === customer) || null, [customers, customer]);

    const handleCustomerChange = (_: unknown, value: Customer | null) => {
        if (value) {
            navigate(`${AdminDashboardRoutes.USAGE_STATS}/${value.name}`);
        } else {
            navigate(AdminDashboardRoutes.USAGE_STATS);
        }
    };

    const error = customersError || statsError;
    if (error) {
        return <Alert severity='error'>{error}</Alert>;
    }

    return (
        <Box>
            <SearchListContainer
                searchContainer={[
                    <CustomerSearch
                        key='customer-search'
                        customers={customers}
                        selectedCustomer={selectedCustomer}
                        loading={customersLoading}
                        onCustomerChange={handleCustomerChange}
                        pageSettings={pageSettings}
                    />
                ]}
                listContainer={!customer && <Alert severity='info'>Select a customer to view usage statistics.</Alert>}
                loading={loading || customersLoading}
            />
            {customer && (
                <UsageStatsChart
                    usageStats={usageStats}
                    dailyP95={dailyP95}
                    customer={selectedCustomer}
                    startDate={startDate}
                    onStartDateChange={setStartDate}
                />
            )}
        </Box>
    );
};