//go:build linux && rootrunner

package host

import (
	"context"
	"crypto/ed25519"
	"crypto/sha256"
	"encoding/hex"
	"net"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/carlosframework/platform/internal/hostbox"
	"github.com/carlosframework/platform/internal/hostclaim"
	execlease "github.com/carlosframework/platform/internal/hostexec"
	"github.com/carlosframework/platform/internal/instancectl"
	"github.com/carlosframework/platform/internal/provision"
	"github.com/carlosframework/platform/internal/release"
	"github.com/carlosframework/platform/internal/rootstate"
)

func plan14BoundSibling(t *testing.T, body []byte, ctl func(context.Context, ...string) (string, error), uid, gid int, lock *release.ReleaseExclusion) func() {
	t.Helper()
	f, disk, rec := generationLaunchFixtureHost(t, "sibling.example")
	host := rec.Host
	for _, dir := range []string{provision.InstanceDir("/data", host), provision.InstanceRunDir(host)} {
		if err := os.MkdirAll(dir, 0755); err != nil {
			t.Fatal(err)
		}
		if err := os.Chown(dir, uid, gid); err != nil {
			t.Fatal(err)
		}
	}
	template, err := unitsFS.ReadFile("units/carlos-instance@.service")
	if err != nil {
		t.Fatal(err)
	}
	// Match the named test's dependency and output adapters.
	lines := plan14RunnerUnitLines(template)
	path := "/run/systemd/system/carlos-instance@.service"
	if err := os.WriteFile(path, []byte(lines), 0644); err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() {
		ctl(context.Background(), "stop", instancectl.UnitName(instancectl.RoleRun, host))
		ctl(context.Background(), "stop", instancectl.SliceName(host))
		os.Remove(path)
		os.RemoveAll(filepath.Join("/run/systemd/system", instancectl.UnitName(instancectl.RoleRun, host)+".d"))
		os.RemoveAll(filepath.Join("/run/systemd/system", instancectl.SliceName(host)+".d"))
		ctl(context.Background(), "daemon-reload")
	})
	if _, err := ctl(t.Context(), "daemon-reload"); err != nil {
		t.Fatal(err)
	}
	store := release.NewDirStore(t.TempDir())
	rec.Schema = 1
	plan14PutRecord(t, store, rec)
	pub, priv, err := ed25519.GenerateKey(nil)
	if err != nil {
		t.Fatal(err)
	}
	if err := release.StageArtifact("/opt/carlos", rec.Account, "sibling", rec.App, body); err != nil {
		t.Fatal(err)
	}
	m := release.Manifest{App: rec.App, Version: "sibling", Kind: "binary", Artifacts: map[string]release.Artifact{release.AdoptPlatform(): {}}}
	if err := release.Ship(t.Context(), store, rec.Account, m, map[string][]byte{release.AdoptPlatform(): body}); err != nil {
		t.Fatal(err)
	}
	if err := release.Promote(t.Context(), store, priv, rec.Account, rec.App, "canary/console", "sibling"); err != nil {
		t.Fatal(err)
	}
	exe := release.VersionPath("/opt/carlos", rec.Account, "sibling", rec.App)
	file, err := rootstate.OpenTrustedFile(exe)
	if err != nil {
		t.Fatal(err)
	}
	id, err := rootstate.Identity(file)
	file.Close()
	if err != nil {
		t.Fatal(err)
	}
	sum := sha256.Sum256(body)
	f.req.Executable, f.req.Spec.Executable, f.req.Spec.Digest = exe, exe, hex.EncodeToString(sum[:])
	f.req.Reservation.Executable = hostbox.LaunchFile{Device: id.Device, Inode: id.Inode}
	socket := filepath.Join(provision.InstanceRunDir(host), "app.sock")
	f.req.Spec.Args = []string{"--socket", socket, "--db", provision.NestedDBPath("/data", host)}
	f.req.Spec.Env = []string{"CARLOS_ADMIN_TOKEN=test", "PLAN14_TENANT_SOCKET=" + socket}
	inputs, err := f.req.Spec.Hash()
	if err != nil {
		t.Fatal(err)
	}
	f.req.Reservation.Inputs = inputs
	f.claims.set(func(c *hostclaim.Claim) { c.Holder.WakeRetry.Attempt.LaunchInputs = inputs })
	f.root.Clock, f.root.DataRoot = execlease.SystemClock{}, "/data"
	f.root.ReadyBudget = 10 * time.Second
	f.root.Units = instancectl.ClaimUnits{Systemctl: ctl, CgroupRoot: "/sys/fs/cgroup", ExeRoot: "/run/carlos-control/exe", UnitRoot: "/run/systemd/system", DataRoot: "/data"}
	f.root.Kernel = linuxClaimLaunchKernel{OptRoot: "/opt/carlos", CgroupRoot: "/sys/fs/cgroup", ProcRoot: "/proc"}
	f.root.generations = &rootGenerationSource{store: store, optDir: "/opt/carlos", pub: func() (ed25519.PublicKey, error) { return pub, nil }, open: func() (rootstate.Store, error) { return disk, nil }, openFile: rootstate.OpenTrustedFile}
	var started hostbox.RoleLaunchResponse
	if err := lock.With(t.Context(), func(ctx context.Context) error {
		var err error
		started, err = f.root.Serve(ctx, f.peer, f.req)
		return err
	}); err != nil {
		t.Fatal("sibling launch", err)
	}
	pin := readGenerationLaunch(t, disk)
	t.Cleanup(func() {
		q := f.req
		q.Op = hostbox.RoleLaunchStop
		q.Spec, q.Executable, q.MemoryMax = nil, "", 0
		if _, err := f.root.Serve(context.Background(), f.peer, q); err != nil {
			t.Error("sibling stop", err)
		}
	})
	return func() {
		t.Helper()
		if got := readGenerationLaunch(t, disk); got != pin {
			t.Fatal("sibling pin changed")
		}
		g := started.Grant
		if err := f.root.Units.Same(t.Context(), instancectl.ClaimUnitStarted{Unit: g.Unit, InvocationID: g.UnitInvocationID, MainPID: g.PID, ControlGroup: g.Group.RelativePath}); err != nil {
			t.Fatal("sibling invocation changed", err)
		}
		transport := &http.Transport{DialContext: func(ctx context.Context, _, _ string) (net.Conn, error) {
			return (&net.Dialer{}).DialContext(ctx, "unix", socket)
		}}
		defer transport.CloseIdleConnections()
		resp, err := (&http.Client{Transport: transport}).Get("http://sibling/")
		if err != nil {
			t.Fatal("sibling stopped serving", err)
		}
		resp.Body.Close()
		if resp.StatusCode != 200 {
			t.Fatal(resp.Status)
		}
	}
}

func plan14RunnerUnitLines(template []byte) string {
	var lines []string
	for _, line := range strings.Split(string(template), "\n") {
		key, _, _ := strings.Cut(line, "=")
		switch key {
		case "BindsTo", "Requires", "After":
			continue
		case "StandardOutput":
			line = "StandardOutput=journal"
		}
		lines = append(lines, line)
	}
	return strings.Join(lines, "\n")
}