package main

import (
	"fmt"
	"io"
	"net"
	"strings"
	"testing"
	"time"

	"github.com/stretchr/testify/require"
)

// TerminalTestClient is a terminal client of a test daemon, with a pipe as its
// input.
type TerminalTestClient struct {
	input *io.PipeWriter
	done  chan error
	out   *SyncBuffer
}

// Type writes one line to the input of the client.
func (c *TerminalTestClient) Type(line string) {
	_, err := io.WriteString(c.input, line+"\n")
	if err != nil {
		panic(err)
	}
}

// Output returns what the client showed.
func (c *TerminalTestClient) Output() string {
	return c.out.String()
}

// WaitFor waits until the client showed text.
func (c *TerminalTestClient) WaitFor(t *testing.T, text string) {
	t.Helper()

	require.Eventually(t, func() bool {
		return strings.Contains(c.Output(), text)
	}, 10*time.Second, time.Millisecond, "output so far: %q", c.Output())
}

// Close ends the input and waits for the client.
func (c *TerminalTestClient) Close() error {
	err := c.input.Close()
	if err != nil {
		return fmt.Errorf("close terminal input: %w", err)
	}

	return <-c.done
}

// terminalStartTestClient connects a client to the daemon at socket.
func terminalStartTestClient(t *testing.T, socket string) *TerminalTestClient {
	t.Helper()

	conn, err := net.Dial("unix", socket)
	require.NoError(t, err)

	reader, writer := io.Pipe()
	client := &TerminalTestClient{
		input: writer,
		done:  make(chan error, 1),
		out:   &SyncBuffer{},
	}

	go func() {
		client.done <- terminalSession(t.Context(), conn, reader, client.out)
	}()

	t.Cleanup(func() {
		_ = writer.Close()
	})

	return client
}