// Copyright (c) 2019-2022 Sylabs Inc. All rights reserved.
// This software is licensed under a 3-clause BSD license. Please consult the
// LICENSE.md file distributed with the sources of this project regarding your
// rights to use or distribute this software.

package oci

import (
	"encoding/json"
	"os"
	"testing"
	"time"

	"github.com/google/uuid"
	specs "github.com/opencontainers/runtime-spec/specs-go"
	"github.com/pkg/errors"
	"github.com/sylabs/singularity/v4/e2e/internal/e2e"
	"github.com/sylabs/singularity/v4/e2e/internal/testhelper"
	"github.com/sylabs/singularity/v4/internal/pkg/test/tool/require"
)

func randomContainerID(t *testing.T) string {
	t.Helper()

	id, err := uuid.NewRandom()
	if err != nil {
		t.Fatal(err)
	}
	return id.String()
}

type ctx struct {
	env e2e.TestEnv
}

func (c *ctx) checkOciState(t *testing.T, containerID string, state specs.ContainerState) {
	ok := false

	checkStateFn := func(t *testing.T, r *e2e.SingularityCmdResult) {
		s := &specs.State{}
		if err := json.Unmarshal(r.Stdout, s); err != nil {
			err = errors.Wrapf(err, "unmarshaling OCI state from JSON: %s", r.Stdout)
			t.Errorf("can't unmarshal oci state output: %+v", err)
			return
		}
		if s.Status != specs.ContainerState(state) {
			t.Logf("bad container state returned, got %s instead of %s", s.Status, state)
			return
		}
		ok = true
	}

	c.env.RunSingularity(
		t,
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci state"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(0, checkStateFn),
	)
	if ok {
		return
	}

	// State transition is slow on EL7/8 ARM64, check again in 1s
	// https://github.com/sylabs/singularity/issues/1437
	t.Logf("Retrying state check in 1s...")
	time.Sleep(time.Second)
	c.env.RunSingularity(
		t,
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci state"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(0, checkStateFn),
	)
	if !ok {
		t.Errorf("Expected state %s not found after retrying", state)
	}
}

func genericOciMount(t *testing.T, c *ctx) (string, func()) {
	require.Seccomp(t)
	require.Command(t, "squashfuse")
	require.Command(t, "fusermount")
	require.Filesystem(t, "overlay")

	bundleDir, err := os.MkdirTemp(c.env.TestDir, "bundle-")
	if err != nil {
		err = errors.Wrapf(err, "creating temporary bundle directory at %q", c.env.TestDir)
		t.Fatalf("failed to create bundle directory: %+v", err)
	}
	c.env.RunSingularity(
		t,
		e2e.AsSubtest("mount"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci mount"),
		e2e.WithArgs(c.env.ImagePath, bundleDir),
		e2e.ExpectExit(0),
	)

	cleanup := func() {
		c.env.RunSingularity(
			t,
			e2e.AsSubtest("umount"),
			e2e.WithProfile(e2e.RootProfile),
			e2e.WithCommand("oci umount"),
			e2e.WithArgs(bundleDir),
			e2e.ExpectExit(0),
		)
	}

	return bundleDir, cleanup
}

func (c ctx) testOciRun(t *testing.T) {
	e2e.EnsureImage(t, c.env)

	containerID := randomContainerID(t)
	bundleDir, umountFn := genericOciMount(t, &c)

	// umount bundle
	defer umountFn()

	// oci run -b
	c.env.RunSingularity(
		t,
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci run"),
		e2e.WithArgs("-b", bundleDir, containerID),
		e2e.ConsoleRun(
			e2e.ConsoleSendLine("hostname"),
			e2e.ConsoleExpect("singularity"),
			e2e.ConsoleSendLine("id -un"),
			e2e.ConsoleExpect("root"),
			e2e.ConsoleSendLine("exit"),
		),
		e2e.ExpectExit(0),
	)

	// oci state should fail
	c.env.RunSingularity(
		t,
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci state"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(255),
	)
}

func (c ctx) testOciAttach(t *testing.T) {
	e2e.EnsureImage(t, c.env)

	containerID := randomContainerID(t)
	bundleDir, umountFn := genericOciMount(t, &c)

	// umount bundle
	defer umountFn()

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("create"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci create"),
		e2e.WithArgs("-b", bundleDir, containerID),
		// this is required otherwise oci create hangs, this is
		// due to command Wait call that waits for the execution of a command
		// that closes standard file descriptors, but OCI create keeps
		// them to respect OCI runtime requirements
		e2e.ConsoleRun(),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.StateCreated)
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("start"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci start"),
		e2e.WithArgs(containerID),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.StateRunning)
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("attach"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci attach"),
		e2e.WithArgs(containerID),
		e2e.ConsoleRun(
			e2e.ConsoleSendLine("hostname"),
			e2e.ConsoleExpect("singularity"),
			e2e.ConsoleSendLine("exit"),
		),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.StateStopped)
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("delete"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci delete"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(0),
	)
}

func (c ctx) testOciBasic(t *testing.T) {
	e2e.EnsureImage(t, c.env)

	containerID := randomContainerID(t)
	bundleDir, umountFn := genericOciMount(t, &c)

	// umount bundle
	defer umountFn()

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("create"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci create"),
		e2e.WithArgs("-b", bundleDir, containerID),
		// this is required otherwise oci create hangs, this is
		// due to command Wait call that waits for the execution of a command
		// that closes standard file descriptors, but OCI create keeps
		// them to respect OCI runtime requirements
		e2e.ConsoleRun(),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.StateCreated)
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("start"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci start"),
		e2e.WithArgs(containerID),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.StateRunning)
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("pause"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci pause"),
		e2e.WithArgs(containerID),
		e2e.PreRun(func(t *testing.T) {
			// skip if cgroups freezer is not available
			require.CgroupsFreezer(t)
		}),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.ContainerState("paused"))
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("resume"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci resume"),
		e2e.WithArgs(containerID),
		e2e.PreRun(func(t *testing.T) {
			// skip if cgroups freezer is not available
			require.CgroupsFreezer(t)
		}),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.StateRunning)
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("start again"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci start"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(255),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("exec"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci exec"),
		e2e.WithArgs(containerID, "hostname"),
		e2e.ExpectExit(0,
			e2e.ExpectOutput(e2e.ContainMatch, "singularity")),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("kill"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci kill"),
		e2e.WithArgs(containerID, "KILL"),
		e2e.PostRun(func(t *testing.T) {
			if !t.Failed() {
				c.checkOciState(t, containerID, specs.StateStopped)
			}
		}),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("delete"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci delete"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(0),
	)

	c.env.RunSingularity(
		t,
		e2e.AsSubtest("state fail"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci state"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(255),
	)
	c.env.RunSingularity(
		t,
		e2e.AsSubtest("kill fail"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci kill"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(255),
	)
	c.env.RunSingularity(
		t,
		e2e.AsSubtest("start fail"),
		e2e.WithProfile(e2e.RootProfile),
		e2e.WithCommand("oci start"),
		e2e.WithArgs(containerID),
		e2e.ExpectExit(255),
	)
}

func (c ctx) testOciHelp(t *testing.T) {
	tests := []struct {
		name          string
		expectedRegex string
	}{
		{
			name:          "attach",
			expectedRegex: `^Attach console to a running container process \(root user only\)`,
		},
		{
			name:          "create",
			expectedRegex: `^Create a container from a bundle directory \(root user only\)`,
		},
		{
			name:          "delete",
			expectedRegex: `^Delete container \(root user only\)`,
		},
		{
			name:          "exec",
			expectedRegex: `^Execute a command within container \(root user only\)`,
		},
		{
			name:          "kill",
			expectedRegex: `^Kill a container \(root user only\)`,
		},
		{
			name:          "mount",
			expectedRegex: `^Mount create an OCI bundle from SIF image \(root user only\)`,
		},
		{
			name:          "pause",
			expectedRegex: `^Suspends all processes inside the container \(root user only\)`,
		},
		{
			name:          "resume",
			expectedRegex: `^Resumes all processes previously paused inside the container \(root user only\)`,
		},
		{
			name:          "run",
			expectedRegex: `^Create/start/attach/delete a container from a bundle directory \(root user only\)`,
		},
		{
			name:          "start",
			expectedRegex: `^Start container process \(root user only\)`,
		},
		{
			name:          "umount",
			expectedRegex: `^Umount delete bundle \(root user only\)`,
		},
		{
			name:          "update",
			expectedRegex: `^Update container cgroups resources \(root user only\)`,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			c.env.RunSingularity(
				t,
				e2e.AsSubtest(tt.name),
				e2e.WithProfile(e2e.UserProfile),
				e2e.WithCommand("oci"),
				e2e.WithArgs([]string{tt.name, "--help"}...),
				e2e.ExpectExit(
					0,
					e2e.ExpectOutput(e2e.RegexMatch, tt.expectedRegex),
				),
			)
		})
	}
}

// E2ETests is the main func to trigger the test suite
func E2ETests(env e2e.TestEnv) testhelper.Tests {
	c := ctx{
		env: env,
	}

	return testhelper.Tests{
		"ordered": testhelper.NoParallel(
			env.WithRootManagers(func(t *testing.T) {
				t.Run("basic", c.testOciBasic)
				t.Run("attach", c.testOciAttach)
				t.Run("run", c.testOciRun)
			})),
		"help": c.testOciHelp,
	}
}