package sentinel

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestCollectUsesCommandOutputAndPkgSample(t *testing.T) {
	dir := fakeSentinelCommands(t)
	t.Setenv("PATH", dir+string(os.PathListSeparator)+os.Getenv("PATH"))

	snap := Collect()
	if snap.Hostname != "titan-13" || snap.Kernel != "6.6.63" || snap.OSImage != "Metis OS" {
		t.Fatalf("unexpected snapshot: %+v", snap)
	}
	if snap.K3sVersion != "v1.31.5+k3s1" || snap.Containerd != "1.7.99" {
		t.Fatalf("unexpected runtime facts: %+v", snap)
	}
	if len(snap.PackageSample) != 4 || snap.PackageSample["k3s"] != "v1.31.5+k3s1" {
		t.Fatalf("unexpected package sample: %+v", snap.PackageSample)
	}
	if snap.USBScratch == nil || snap.USBScratch.Label != "titan-16-scratch" || !snap.USBScratch.MountHealthy || !snap.USBScratch.LabelHealthy || !snap.USBScratch.BindHealthy {
		t.Fatalf("unexpected usb scratch sample: %+v", snap.USBScratch)
	}
}

func TestCommandOutputUsesNsenterWhenRequested(t *testing.T) {
	dir := fakeSentinelCommands(t)
	t.Setenv("PATH", dir+string(os.PathListSeparator)+os.Getenv("PATH"))
	t.Setenv("METIS_SENTINEL_NSENTER", "1")

	got, err := commandOutput("ignored", "arg")
	if err != nil {
		t.Fatalf("commandOutput: %v", err)
	}
	if strings.TrimSpace(string(got)) != "nsenter-ok" {
		t.Fatalf("unexpected nsenter output: %q", string(got))
	}
}

func TestRunAndTrimAndPkgVersionFallbacks(t *testing.T) {
	dir := t.TempDir()
	write := func(name, body string) {
		path := filepath.Join(dir, name)
		if err := os.WriteFile(path, []byte("#!/usr/bin/env bash\nset -eu\n"+body+"\n"), 0o755); err != nil {
			t.Fatalf("write %s: %v", name, err)
		}
	}
	write("cat", `printf 'ID=metis\n'`)
	write("rpm", `exit 1`)
	t.Setenv("PATH", dir+string(os.PathListSeparator)+os.Getenv("PATH"))

	if got := runAndTrim("missing-command"); got != "" {
		t.Fatalf("runAndTrim missing command = %q", got)
	}
	if got := osRelease(); got != "" {
		t.Fatalf("osRelease without PRETTY_NAME = %q", got)
	}
	if got := pkgVersion("does-not-exist"); got != "" {
		t.Fatalf("pkgVersion fallback = %q", got)
	}
}

func fakeSentinelCommands(t *testing.T) string {
	t.Helper()
	dir := t.TempDir()
	write := func(name, body string) {
		path := filepath.Join(dir, name)
		if err := os.WriteFile(path, []byte("#!/usr/bin/env bash\nset -eu\n"+body+"\n"), 0o755); err != nil {
			t.Fatalf("write %s: %v", name, err)
		}
	}
	write("hostname", `printf 'titan-13\n'`)
	write("uname", `printf '6.6.63\n'`)
	write("k3s", `printf 'v1.31.5+k3s1\n'`)
	write("containerd", `printf '1.7.99\n'`)
	write("cat", `case "${1:-}" in
  /etc/os-release) printf 'PRETTY_NAME="Metis OS"\n' ;;
  /etc/metis/node.json) printf '%s\n' '{"usb_scratch":{"mountpoint":"/mnt/scratch","label":"titan-16-scratch","fs":"ext4","bind_targets":["/var/lib/rancher","/var/log"]}}' ;;
  *) printf 'PRETTY_NAME="Metis OS"\n' ;;
esac`)
	write("findmnt", `target=""
for ((i=1; i<=$#; i++)); do
  if [[ "${!i}" == "-T" ]]; then
    j=$((i + 1))
    target="${!j}"
    break
  fi
done
case "${target}" in
  /mnt/scratch) printf 'SOURCE="/dev/sdz1" TARGET="/mnt/scratch" FSTYPE="ext4"\n' ;;
  /var/lib/rancher) printf 'SOURCE="/mnt/scratch" TARGET="/var/lib/rancher" FSTYPE="none"\n' ;;
  /var/log) printf 'SOURCE="/mnt/scratch" TARGET="/var/log" FSTYPE="none"\n' ;;
  *) exit 1 ;;
esac`)
	write("blkid", `case "${1:-}" in
  -U) printf '/dev/sdz1\n' ;;
  -L) printf '/dev/sdz1\n' ;;
  -o) printf 'UUID=titan-16-uuid\nLABEL=titan-16-scratch\nTYPE=ext4\n' ;;
esac`)
	write("dpkg-query", `case "${@: -1}" in
  containerd) printf '1.7.99\n' ;;
  k3s) printf 'v1.31.5+k3s1\n' ;;
  nvidia-container-toolkit) printf '1.16.2\n' ;;
  linux-image-raspi) printf '6.6.63\n' ;;
  *) printf '1.0.0\n' ;;
esac`)
	write("rpm", `printf '1.0.0\n'`)
	write("nsenter", `printf 'nsenter-ok\n'`)
	return dir
}