package host

import (
	"context"
	"errors"
	"runtime"
	"testing"
	"time"

	"github.com/carlosframework/platform/internal/registry"
	"github.com/carlosframework/platform/internal/release"
)

// Issue #315, through the fast loop's production options: an agent that is
// not root hands a named-unit route to root's pass rather than repointing it
// and failing systemd's permission check. An agent run as root keeps
// restarting the unit itself.
func TestFastSweepHandsANamedUnitToRoot(t *testing.T) {
	for _, tc := range []struct {
		name string
		root bool
	}{{"agent user", false}, {"root", true}} {
		t.Run(tc.name, func(t *testing.T) {
			was := agentRunsAsRoot
			agentRunsAsRoot = func() bool { return tc.root }
			t.Cleanup(func() { agentRunsAsRoot = was })

			env := newFastFixture(t)
			ctx := context.Background()
			plat := runtime.GOOS + "-" + runtime.GOARCH
			for _, v := range []string{"v1", "v2"} {
				m := release.Manifest{App: "fastapp", Version: v, Kind: "binary",
					Artifacts: map[string]release.Artifact{plat: {}}}
				if err := release.Ship(ctx, env.store, "bab", m, map[string][]byte{plat: []byte("build " + v)}); err != nil {
					t.Fatalf("Ship %s: %v", v, err)
				}
			}
			if err := release.Promote(ctx, env.store, env.priv, "bab", "fastapp", "canary/dev", "v1"); err != nil {
				t.Fatal(err)
			}
			if err := env.reg.Upsert(registry.Route{Host: "console.test", Kind: "instance", App: "fastapp",
				Channel: "canary/dev", Status: "ready", Addr: "127.0.0.1:8090"}); err != nil {
				t.Fatal(err)
			}
			if err := release.Pass(ctx, env.reg, env.store, env.pub, env.optDir, nil); err != nil {
				t.Fatal(err)
			}
			if err := env.reg.SetUnit("console.test", "console.service"); err != nil {
				t.Fatal(err)
			}
			if err := release.Promote(ctx, env.store, env.priv, "bab", "fastapp", "canary/dev", "v2"); err != nil {
				t.Fatal(err)
			}

			var unitRestarts []string
			restart := makeRestartRoute(env.reg, func(string) {},
				unitOnly(func(u string) error { unitRestarts = append(unitRestarts, u); return nil }), nil)
			var relayed []error
			stageReq := func(host, ver string, err error) {
				if host == "console.test" && ver == "v2" {
					relayed = append(relayed, err)
				}
			}
			d := env.deps(nil)
			d.restart = restart
			d.passOpts = fastPassOpts(env.dataDir, stageReq, restart, nil)

			fastTick(ctx, d, time.Unix(1754640000, 0))

			live, err := release.LiveVersion(env.optDir, "console.test")
			if err != nil {
				t.Fatal(err)
			}
			if tc.root {
				if live != "v2" || len(unitRestarts) != 1 || len(relayed) != 0 {
					t.Fatalf("root agent: live %q, unit restarts %v, relays %v; want v2, one restart, no relay", live, unitRestarts, relayed)
				}
				return
			}
			if live != "v1" || len(unitRestarts) != 0 {
				t.Fatalf("agent user: live %q, unit restarts %v; want v1 untouched and no restart", live, unitRestarts)
			}
			if len(relayed) != 1 || !errors.Is(relayed[0], release.ErrUnitRestartNeedsRoot) {
				t.Fatalf("relays = %v, want one ErrUnitRestartNeedsRoot", relayed)
			}
		})
	}
}