package integration

import (
	"bytes"
	"fmt"
	"io"
	"os"
	"strconv"
	"strings"
	"syscall"
	"testing"
	"time"

	"github.com/opencontainers/runc/libcontainer"
	"github.com/opencontainers/runc/libcontainer/configs"
)

func TestExecIn(t *testing.T) {
	if testing.Short() {
		return
	}
	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)
	config := newTemplateConfig(rootfs)
	container, err := newContainer(config)
	ok(t, err)
	defer container.Destroy()

	// Execute a first process in the container
	stdinR, stdinW, err := os.Pipe()
	ok(t, err)
	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer stdinW.Close()
	ok(t, err)

	buffers := newStdBuffers()
	ps := &libcontainer.Process{
		Cwd:    "/",
		Args:   []string{"ps"},
		Env:    standardEnvironment,
		Stdin:  buffers.Stdin,
		Stdout: buffers.Stdout,
		Stderr: buffers.Stderr,
	}

	err = container.Start(ps)
	ok(t, err)
	waitProcess(ps, t)
	stdinW.Close()
	waitProcess(process, t)

	out := buffers.Stdout.String()
	if !strings.Contains(out, "cat") || !strings.Contains(out, "ps") {
		t.Fatalf("unexpected running process, output %q", out)
	}
}

func TestExecInUsernsRlimit(t *testing.T) {
	if _, err := os.Stat("/proc/self/ns/user"); os.IsNotExist(err) {
		t.Skip("userns is unsupported")
	}

	testExecInRlimit(t, true)
}

func TestExecInRlimit(t *testing.T) {
	testExecInRlimit(t, false)
}

func testExecInRlimit(t *testing.T, userns bool) {
	if testing.Short() {
		return
	}

	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)

	config := newTemplateConfig(rootfs)
	if userns {
		config.UidMappings = []configs.IDMap{{0, 0, 1000}}
		config.GidMappings = []configs.IDMap{{0, 0, 1000}}
		config.Namespaces = append(config.Namespaces, configs.Namespace{Type: configs.NEWUSER})
	}

	container, err := newContainer(config)
	ok(t, err)
	defer container.Destroy()

	stdinR, stdinW, err := os.Pipe()
	ok(t, err)
	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer stdinW.Close()
	ok(t, err)

	buffers := newStdBuffers()
	ps := &libcontainer.Process{
		Cwd:    "/",
		Args:   []string{"/bin/sh", "-c", "ulimit -n"},
		Env:    standardEnvironment,
		Stdin:  buffers.Stdin,
		Stdout: buffers.Stdout,
		Stderr: buffers.Stderr,
		Rlimits: []configs.Rlimit{
			// increase process rlimit higher than container rlimit to test per-process limit
			{Type: syscall.RLIMIT_NOFILE, Hard: 1026, Soft: 1026},
		},
	}
	err = container.Start(ps)
	ok(t, err)
	waitProcess(ps, t)

	stdinW.Close()
	waitProcess(process, t)

	out := buffers.Stdout.String()
	if limit := strings.TrimSpace(out); limit != "1026" {
		t.Fatalf("expected rlimit to be 1026, got %s", limit)
	}
}

func TestExecInError(t *testing.T) {
	if testing.Short() {
		return
	}
	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)
	config := newTemplateConfig(rootfs)
	container, err := newContainer(config)
	ok(t, err)
	defer container.Destroy()

	// Execute a first process in the container
	stdinR, stdinW, err := os.Pipe()
	ok(t, err)
	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer func() {
		stdinW.Close()
		if _, err := process.Wait(); err != nil {
			t.Log(err)
		}
	}()
	ok(t, err)

	for i := 0; i < 42; i++ {
		var out bytes.Buffer
		unexistent := &libcontainer.Process{
			Cwd:    "/",
			Args:   []string{"unexistent"},
			Env:    standardEnvironment,
			Stdout: &out,
		}
		err = container.Start(unexistent)
		if err == nil {
			t.Fatal("Should be an error")
		}
		if !strings.Contains(err.Error(), "executable file not found") {
			t.Fatalf("Should be error about not found executable, got %s", err)
		}
		if !bytes.Contains(out.Bytes(), []byte("executable file not found")) {
			t.Fatalf("executable file not found error not delivered to stdio:\n%s", out.String())
		}
	}
}

func TestExecInTTY(t *testing.T) {
	if testing.Short() {
		return
	}
	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)
	config := newTemplateConfig(rootfs)
	container, err := newContainer(config)
	ok(t, err)
	defer container.Destroy()

	// Execute a first process in the container
	stdinR, stdinW, err := os.Pipe()
	ok(t, err)
	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer stdinW.Close()
	ok(t, err)

	var stdout bytes.Buffer
	ps := &libcontainer.Process{
		Cwd:  "/",
		Args: []string{"ps"},
		Env:  standardEnvironment,
	}
	console, err := ps.NewConsole(0)
	copy := make(chan struct{})
	go func() {
		io.Copy(&stdout, console)
		close(copy)
	}()
	ok(t, err)
	err = container.Start(ps)
	ok(t, err)
	select {
	case <-time.After(5 * time.Second):
		t.Fatal("Waiting for copy timed out")
	case <-copy:
	}
	waitProcess(ps, t)

	stdinW.Close()
	waitProcess(process, t)

	out := stdout.String()
	if !strings.Contains(out, "cat") || !strings.Contains(string(out), "ps") {
		t.Fatalf("unexpected running process, output %q", out)
	}
}

func TestExecInEnvironment(t *testing.T) {
	if testing.Short() {
		return
	}
	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)
	config := newTemplateConfig(rootfs)
	container, err := newContainer(config)
	ok(t, err)
	defer container.Destroy()

	// Execute a first process in the container
	stdinR, stdinW, err := os.Pipe()
	ok(t, err)
	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer stdinW.Close()
	ok(t, err)

	buffers := newStdBuffers()
	process2 := &libcontainer.Process{
		Cwd:  "/",
		Args: []string{"env"},
		Env: []string{
			"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
			"DEBUG=true",
			"DEBUG=false",
			"ENV=test",
		},
		Stdin:  buffers.Stdin,
		Stdout: buffers.Stdout,
		Stderr: buffers.Stderr,
	}
	err = container.Start(process2)
	ok(t, err)
	waitProcess(process2, t)

	stdinW.Close()
	waitProcess(process, t)

	out := buffers.Stdout.String()
	// check execin's process environment
	if !strings.Contains(out, "DEBUG=false") ||
		!strings.Contains(out, "ENV=test") ||
		!strings.Contains(out, "HOME=/root") ||
		!strings.Contains(out, "PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin") ||
		strings.Contains(out, "DEBUG=true") {
		t.Fatalf("unexpected running process, output %q", out)
	}
}

func TestExecinPassExtraFiles(t *testing.T) {
	if testing.Short() {
		return
	}
	rootfs, err := newRootfs()
	if err != nil {
		t.Fatal(err)
	}
	defer remove(rootfs)
	config := newTemplateConfig(rootfs)
	container, err := newContainer(config)
	if err != nil {
		t.Fatal(err)
	}
	defer container.Destroy()

	// Execute a first process in the container
	stdinR, stdinW, err := os.Pipe()
	if err != nil {
		t.Fatal(err)
	}
	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer stdinW.Close()
	if err != nil {
		t.Fatal(err)
	}

	var stdout bytes.Buffer
	pipeout1, pipein1, err := os.Pipe()
	pipeout2, pipein2, err := os.Pipe()
	inprocess := &libcontainer.Process{
		Cwd:        "/",
		Args:       []string{"sh", "-c", "cd /proc/$$/fd; echo -n *; echo -n 1 >3; echo -n 2 >4"},
		Env:        []string{"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"},
		ExtraFiles: []*os.File{pipein1, pipein2},
		Stdin:      nil,
		Stdout:     &stdout,
	}
	err = container.Start(inprocess)
	if err != nil {
		t.Fatal(err)
	}

	waitProcess(inprocess, t)
	stdinW.Close()
	waitProcess(process, t)

	out := string(stdout.Bytes())
	// fd 5 is the directory handle for /proc/$$/fd
	if out != "0 1 2 3 4 5" {
		t.Fatalf("expected to have the file descriptors '0 1 2 3 4 5' passed to exec, got '%s'", out)
	}
	var buf = []byte{0}
	_, err = pipeout1.Read(buf)
	if err != nil {
		t.Fatal(err)
	}
	out1 := string(buf)
	if out1 != "1" {
		t.Fatalf("expected first pipe to receive '1', got '%s'", out1)
	}

	_, err = pipeout2.Read(buf)
	if err != nil {
		t.Fatal(err)
	}
	out2 := string(buf)
	if out2 != "2" {
		t.Fatalf("expected second pipe to receive '2', got '%s'", out2)
	}
}

func TestExecInOomScoreAdj(t *testing.T) {
	if testing.Short() {
		return
	}
	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)
	config := newTemplateConfig(rootfs)
	config.OomScoreAdj = 200
	container, err := newContainer(config)
	ok(t, err)
	defer container.Destroy()

	stdinR, stdinW, err := os.Pipe()
	ok(t, err)
	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer stdinW.Close()
	ok(t, err)

	buffers := newStdBuffers()
	ps := &libcontainer.Process{
		Cwd:    "/",
		Args:   []string{"/bin/sh", "-c", "cat /proc/self/oom_score_adj"},
		Env:    standardEnvironment,
		Stdin:  buffers.Stdin,
		Stdout: buffers.Stdout,
		Stderr: buffers.Stderr,
	}
	err = container.Start(ps)
	ok(t, err)
	waitProcess(ps, t)

	stdinW.Close()
	waitProcess(process, t)

	out := buffers.Stdout.String()
	if oomScoreAdj := strings.TrimSpace(out); oomScoreAdj != strconv.Itoa(config.OomScoreAdj) {
		t.Fatalf("expected oomScoreAdj to be %d, got %s", config.OomScoreAdj, oomScoreAdj)
	}
}

func TestExecInUserns(t *testing.T) {
	if _, err := os.Stat("/proc/self/ns/user"); os.IsNotExist(err) {
		t.Skip("userns is unsupported")
	}
	if testing.Short() {
		return
	}
	rootfs, err := newRootfs()
	ok(t, err)
	defer remove(rootfs)
	config := newTemplateConfig(rootfs)
	config.UidMappings = []configs.IDMap{{0, 0, 1000}}
	config.GidMappings = []configs.IDMap{{0, 0, 1000}}
	config.Namespaces = append(config.Namespaces, configs.Namespace{Type: configs.NEWUSER})
	container, err := newContainer(config)
	ok(t, err)
	defer container.Destroy()

	// Execute a first process in the container
	stdinR, stdinW, err := os.Pipe()
	ok(t, err)

	process := &libcontainer.Process{
		Cwd:   "/",
		Args:  []string{"cat"},
		Env:   standardEnvironment,
		Stdin: stdinR,
	}
	err = container.Start(process)
	stdinR.Close()
	defer stdinW.Close()
	ok(t, err)

	initPID, err := process.Pid()
	ok(t, err)
	initUserns, err := os.Readlink(fmt.Sprintf("/proc/%d/ns/user", initPID))
	ok(t, err)

	buffers := newStdBuffers()
	process2 := &libcontainer.Process{
		Cwd:  "/",
		Args: []string{"readlink", "/proc/self/ns/user"},
		Env: []string{
			"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
		},
		Stdout: buffers.Stdout,
		Stderr: os.Stderr,
	}
	err = container.Start(process2)
	ok(t, err)
	waitProcess(process2, t)
	stdinW.Close()
	waitProcess(process, t)

	if out := strings.TrimSpace(buffers.Stdout.String()); out != initUserns {
		t.Errorf("execin userns(%s), wanted %s", out, initUserns)
	}
}