/*
Copyright 2026 linux.do
Modified by Arctel.net, 2026

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.
*/

package mail

import (
	"bufio"
	"net"
	"net/textproto"
	"testing"
)

func TestSendMailMock(t *testing.T) {
	// Start a mock SMTP server
	l, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("failed to start mock smtp server: %v", err)
	}
	defer l.Close()

	port := l.Addr().(*net.TCPAddr).Port

	go func() {
		conn, err := l.Accept()
		if err != nil {
			return
		}
		defer conn.Close()

		writer := bufio.NewWriter(conn)
		reader := bufio.NewReader(conn)
		tp := textproto.NewReader(reader)

		// 220 Ready
		_, _ = writer.WriteString("220 mock.smtp.com SMTP Ready\r\n")
		_ = writer.Flush()

		// Read HELO/EHLO
		_, _ = tp.ReadLine()
		_, _ = writer.WriteString("250-mock.smtp.com\r\n250 AUTH PLAIN\r\n")
		_ = writer.Flush()

		// Read AUTH PLAIN
		_, _ = tp.ReadLine()
		_, _ = writer.WriteString("235 Authentication successful\r\n")
		_ = writer.Flush()

		// Read MAIL FROM
		_, _ = tp.ReadLine()
		_, _ = writer.WriteString("250 OK\r\n")
		_ = writer.Flush()

		// Read RCPT TO
		_, _ = tp.ReadLine()
		_, _ = writer.WriteString("250 OK\r\n")
		_ = writer.Flush()

		// Read DATA
		_, _ = tp.ReadLine()
		_, _ = writer.WriteString("354 Start mail input\r\n")
		_ = writer.Flush()

		// Read body lines until dot
		for {
			line, err := tp.ReadLine()
			if err != nil || line == "." {
				break
			}
		}
		_, _ = writer.WriteString("250 OK\r\n")
		_ = writer.Flush()

		// Read QUIT
		_, _ = tp.ReadLine()
		_, _ = writer.WriteString("221 Bye\r\n")
		_ = writer.Flush()
	}()

	cfg := Config{
		Host:     "127.0.0.1",
		Port:     port,
		Username: "test@example.com",
		Password: "password",
	}

	err = SendMail(cfg, "recipient@example.com", "Test Subject", "<h1>Test Body</h1>")
	if err != nil {
		t.Errorf("failed to send mail: %v", err)
	}
}