package host

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

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

func TestPlan14IdenticalVersionKeepsRollbackEvidence(t *testing.T) {
	if !plan14RootFixture(t) {
		return
	}
	e, rt, u, c, _ := plan14AdoptionFixture(t)
	if err := os.MkdirAll("/var/lib", 0755); err != nil {
		t.Fatal(err)
	}
	if err := rootstate.EnsurePublicDir(release.RootHealthyDir); err != nil {
		t.Fatal(err)
	}
	evidence := release.ReadHealthy(e.bake, rt.Account, rt.App)[0]
	if err := release.RecordHealthy(release.RootHealthyDir, rt.Account, rt.App, evidence); err != nil {
		t.Fatal(err)
	}
	original, err := os.ReadFile(filepath.Join(release.RootHealthyDir, "healthy", rt.Account, rt.App+".json"))
	if err != nil {
		t.Fatal(err)
	}
	raw, err := os.ReadFile(u.exe)
	if err != nil {
		t.Fatal(err)
	}
	v2 := release.VersionPath(u.opt, rt.Account, "v2", rt.App)
	if err := os.MkdirAll(filepath.Dir(v2), 0755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(v2, raw, 0755); err != nil {
		t.Fatal(err)
	}
	if err := release.PointLive(u.opt, rt.Host, rt.Account, "v2", rt.App); err != nil {
		t.Fatal(err)
	}
	u.exe = v2
	makeProofAncestorsPublic(t, u.exe)
	makeProofAncestorsPublic(t, u.props.FragmentPath)
	s := productionProofBindingSource(e.store, u, u.opt)
	s.unitDirs = []string{filepath.Dir(u.props.FragmentPath)}
	c.resolve, c.host, c.rollback, c.prepareRollback, c.targetFile = s.resolve, s.forHost, s.rollback, s.prepareRollback, rootstate.OpenTrustedFile
	c.attempts = productionRootRestartChecks(u, u.opt).attempts
	e.root.obs.resolve = s.resolve
	e.bake = release.RootHealthyDir
	if err := e.root.obs.recordSettled(e.bake)(rt); err != nil {
		t.Fatal(err)
	}
	b, err := s.resolve(t.Context(), rt)
	if err != nil {
		t.Fatal(err)
	}
	if b.Version != "v2" || !b.Historical || b.History == nil || *b.History != evidence {
		t.Fatalf("binding: %+v", b)
	}
	captured := false
	u.afterRestart = func() {
		state, err := c.attempts()
		if err != nil {
			t.Fatal(err)
		}
		defer state.Close()
		_, b, err := loadRollback(state, rt.Host, c.now())
		if err != nil {
			t.Fatal(err)
		}
		if b.Version != "v2" || b.History.Version != "v1" {
			t.Fatal("evidence rewritten", b)
		}
		if _, err := s.prepareRollback(t.Context(), b); err != nil {
			t.Fatal("v2 rollback not authorized", err)
		}
		captured = true
	}
	if err := checkedUnitRestart(u, u.opt, func(string) string { return "5s" }, e.root.obs.recordSettled(e.bake), c)(rt); err != nil {
		t.Fatal(err)
	}
	if !captured || len(u.effects) != 1 {
		t.Fatal("restart not captured", u.effects)
	}
	after, err := os.ReadFile(filepath.Join(release.RootHealthyDir, "healthy", rt.Account, rt.App+".json"))
	if err != nil {
		t.Fatal(err)
	}
	if string(after) != string(original) {
		t.Fatal("B4 evidence changed")
	}
}