package host

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

	"github.com/carlosframework/platform/internal/hostclaim"
	"github.com/carlosframework/platform/internal/hostguard"
)

func TestPlan14RootLaunchRefusesReplacedAgentFence(t *testing.T) {
	for _, attack := range []string{"honest", "delete", "rename", "replace lock", "forge", "receipt replay"} {
		t.Run(attack, func(t *testing.T) {
			f := newLaunchFixture(t, servingOp())
			f.claims.set(func(c *hostclaim.Claim) {
				c.Holder.Account = "bab"
				c.Holder.App = "app"
				c.Holder.Admissions = []hostclaim.AdmissionRecord{{Box: f.target.Box, Region: f.target.Region, Session: f.target.Session, Generation: c.Holder.Generation}}
			})
			guard := f.root.Guard
			guard.Root = hostguard.NewRootAuthority(&rollbackDisk{dir: t.TempDir()})
			in := hostguard.RootInstallation{Host: f.target.Host, Account: "bab", App: "app", Record: "record", Incarnation: f.target.Incarnation, Stamp: f.target.Stamp, Box: f.target.Box, Enrollment: f.target.Enrollment, Migration: 1}
			if err := guard.EstablishRoot(t.Context(), in, func(*hostclaim.Claim) error { return nil }); err != nil {
				t.Fatal(err)
			}
			f.root.Guard = guard
			if attack == "honest" {
				if _, err := f.root.Serve(t.Context(), f.peer, f.req); err != nil {
					t.Fatal(err)
				}
				if n, _ := f.units.counts(); n != 1 {
					t.Fatalf("honest launch count: %d", n)
				}
				return
			}
			if attack == "receipt replay" {
				if _, err := f.root.Serve(t.Context(), f.peer, f.req); err != nil {
					t.Fatal(err)
				}
			}
			target := f.target
			target.FenceID = "root-fence"
			if _, err := guard.BeginFence(t.Context(), target); err != nil {
				t.Fatal(err)
			}
			path := filepath.Join(guard.DataDir, "hostguard", target.Host+".json")
			switch attack {
			case "delete":
				if err := os.Remove(path); err != nil {
					t.Fatal(err)
				}
			case "rename":
				if err := os.Rename(filepath.Dir(path), filepath.Dir(path)+".old"); err != nil {
					t.Fatal(err)
				}
			case "replace lock":
				if err := os.Rename(guard.LockDir, guard.LockDir+".old"); err != nil {
					t.Fatal(err)
				}
				if err := os.Mkdir(guard.LockDir, 0700); err != nil {
					t.Fatal(err)
				}
			case "forge":
				if err := os.WriteFile(path, []byte(`{"v":1,"host":"shop.example","incarnation":"inc-1","active_stamp":11}`), 0600); err != nil {
					t.Fatal(err)
				}
			}
			before, _ := f.units.counts()
			if _, err := f.root.Serve(t.Context(), f.peer, f.req); err == nil {
				t.Fatal("root launch bypassed fence")
			}
			if n, _ := f.units.counts(); n != before {
				t.Fatal("fenced launch started a unit")
			}
			pending, err := guard.PendingFences(t.Context())
			if err != nil || len(pending) != 1 || pending[0] != target {
				t.Fatalf("lost root recovery target: %+v %v", pending, err)
			}
		})
	}
}