package main

import (
	"bufio"
	"encoding/json"
	"fmt"
	"io"
	"net"
	"os"
	"testing"
	"time"
)

func TestAutomaticLoginWaitsForSuccessAndPreservesBufferedData(t *testing.T) {
	for _, accepted := range []bool{true, false} {
		t.Run(fmt.Sprint(accepted), func(t *testing.T) {
			client, server := net.Pipe()
			defer client.Close()
			defer server.Close()
			done := make(chan error, 1)
			go func() {
				r := bufio.NewReader(server)
				fmt.Fprint(server, "DebTik login: ")
				user, err := r.ReadString('\n')
				if err != nil {
					done <- err
					return
				}
				fmt.Fprint(server, "Password: ")
				password, err := r.ReadString('\n')
				if err != nil {
					done <- err
					return
				}
				if user != "admin\n" || password != "test-password\n" {
					done <- fmt.Errorf("wrong credentials sent")
					return
				}
				if accepted {
					_, err = fmt.Fprint(server, "Welcome\n[admin@router] > buffered")
				} else {
					_, err = fmt.Fprint(server, "Login failed: invalid credentials\n")
				}
				done <- err
			}()
			r := bufio.NewReader(client)
			err := autoLogin(client, r, "admin", "test-password", io.Discard)
			if (err == nil) != accepted {
				t.Fatalf("accepted=%v err=%v", accepted, err)
			}
			if accepted {
				buffered := make([]byte, 8)
				if _, err := r.Read(buffered); err != nil || string(buffered) != "buffered" {
					t.Fatal("buffered data was lost")
				}
			}
			if err := <-done; err != nil {
				t.Fatal(err)
			}
		})
	}
}

func TestOneShotReportsCommandFailure(t *testing.T) {
	for _, status := range []string{"0", "1", "missing"} {
		t.Run(status, func(t *testing.T) {
			client, server := net.Pipe()
			defer client.Close()
			go func() {
				defer server.Close()
				r := bufio.NewReader(server)
				fmt.Fprint(server, "login:")
				r.ReadString('\n')
				fmt.Fprint(server, "password:")
				r.ReadString('\n')
				fmt.Fprint(server, "[user@router] > ")
				r.ReadString('\n')
				if status != "missing" {
					fmt.Fprintf(server, "DEBTIK-EXEC-BEGIN\nresult\nDEBTIK-EXEC-STATUS:%s\n", status)
				}
			}()
			err := runOneShot(client, "user", "password", "invalid", time.Second, false)
			if (err == nil) != (status == "0") {
				t.Fatalf("status %s: %v", status, err)
			}
		})
	}
}

func TestOneShotJSONEnvelope(t *testing.T) {
	client, server := net.Pipe()
	defer client.Close()
	go func() {
		defer server.Close()
		r := bufio.NewReader(server)
		fmt.Fprint(server, "login:")
		r.ReadString('\n')
		fmt.Fprint(server, "password:")
		r.ReadString('\n')
		fmt.Fprint(server, "[user@router] > ")
		r.ReadString('\n')
		fmt.Fprint(server, "echoed command\r\nDEBTIK-EXEC-BEGIN\r\nresult\r\nDEBTIK-EXEC-STATUS:1\r\n")
	}()
	original := os.Stdout
	read, write, err := os.Pipe()
	if err != nil {
		t.Fatal(err)
	}
	os.Stdout = write
	defer func() { os.Stdout = original; read.Close() }()
	err = runOneShot(client, "user", "password", "invalid", time.Second, true)
	write.Close()
	if err == nil {
		t.Fatal("expected failure")
	}
	var got struct {
		Output string `json:"output"`
		Status int    `json:"status"`
		OK     bool   `json:"ok"`
	}
	if err := json.NewDecoder(read).Decode(&got); err != nil {
		t.Fatal(err)
	}
	if got.OK || got.Status != 1 || got.Output != "result\r\n" {
		t.Fatalf("unexpected envelope: %+v", got)
	}
}