// Copyright 2024 iLogtail Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//go:build linux
// +build linux

package containercenter

import (
	"context"
	"fmt"
	"net"
	"net/url"
	"time"

	"github.com/alibaba/ilogtail/pkg/logger"
)

var containerdUnixSocket = "/run/containerd/containerd.sock"

// GetAddressAndDialer returns the address parsed from the given endpoint and a dialer.
func GetAddressAndDialer(endpoint string) (string, func(addr string, timeout time.Duration) (net.Conn, error), error) {
	endpoint = "unix://" + endpoint
	protocol, addr, err := parseEndpointWithFallbackProtocol(endpoint, "unix")
	if err != nil {
		return "", nil, err
	}
	if protocol != "unix" {
		return "", nil, fmt.Errorf("only support unix socket endpoint")
	}

	return addr, dial, nil
}

func parseEndpointWithFallbackProtocol(endpoint string, fallbackProtocol string) (protocol string, addr string, err error) {
	if protocol, addr, err = parseEndpoint(endpoint); err != nil && protocol == "" {
		fallbackEndpoint := fallbackProtocol + "://" + endpoint
		protocol, addr, err = parseEndpoint(fallbackEndpoint)
		if err == nil {
			logger.Infof(context.Background(), "Using %q as endpoint is deprecated, please consider using full url format %q.", endpoint, fallbackEndpoint)
		}
	}
	return
}

func parseEndpoint(endpoint string) (string, string, error) {
	u, err := url.Parse(endpoint)
	if err != nil {
		return "", "", err
	}

	switch u.Scheme {
	case "tcp":
		return "tcp", u.Host, nil

	case "unix":
		return "unix", u.Path, nil

	case "":
		return "", "", fmt.Errorf("using %q as endpoint is deprecated, please consider using full url format", endpoint)

	default:
		return u.Scheme, "", fmt.Errorf("protocol %q not supported", u.Scheme)
	}
}

func dial(addr string, timeout time.Duration) (net.Conn, error) {
	return net.DialTimeout("unix", addr, timeout)
}
