package release

import (
	"crypto/ed25519"
	"crypto/rand"
	"errors"
	"reflect"
	"testing"
	"time"
)

func identityRelease(tag, router, console string) SystemRelease {
	return SystemRelease{Version: tag, Source: "release:" + tag, ReleaseTag: tag, MovesProtocol: 1,
		Artifacts:        map[string]SystemArtifact{"linux-arm64": {Key: SystemArtifactKey(tag, "linux-arm64"), SHA256: router}},
		ConsoleArtifacts: map[string]SystemArtifact{"linux-arm64": {Key: "bootstrap/console/" + tag + "/carlos-linux-arm64", SHA256: console}}}
}

// SignSystemIdentity is the trusted host's signer for a release identity.
// Two signatures of one release are different bytes (promoted_at moves) but
// the same Current, so PublishSystemIdentity takes the second as a no-op and
// refuses a different release under the same tag.
func TestSignSystemIdentityPublishesCreateOnly(t *testing.T) {
	pub, key, _ := ed25519.GenerateKey(rand.Reader)
	sg := RootSigner(key)
	rel := identityRelease("v0.28.2", hexOf('a'), hexOf('b'))
	first, err := SignSystemIdentity(sg, rel)
	if err != nil {
		t.Fatal(err)
	}
	p, err := VerifySystemIdentity(pub, first)
	if err != nil {
		t.Fatal(err)
	}
	if p.Component != SystemComponentRouter || p.Channel != "stable" || p.Spread != "0s" || len(p.History) != 0 || len(p.Audit) != 0 || !reflect.DeepEqual(p.Current, rel) {
		t.Fatalf("identity %+v", p)
	}
	s := NewDirStore(t.TempDir())
	ctx := t.Context()
	if err = PublishSystemIdentity(ctx, s, pub, first); err != nil {
		t.Fatal(err)
	}
	time.Sleep(1100 * time.Millisecond) // promoted_at has one-second resolution
	second, err := SignSystemIdentity(sg, rel)
	if err != nil {
		t.Fatal(err)
	}
	if string(second) == string(first) {
		t.Fatal("expected a fresh signature")
	}
	if err = PublishSystemIdentity(ctx, s, pub, second); err != nil {
		t.Fatal("same release refused", err)
	}
	stored, _, err := s.Get(ctx, "control/system/router/releases/v0.28.2.json")
	if err != nil || string(stored) != string(first) {
		t.Fatal("create-only identity was replaced", err)
	}
	other, err := SignSystemIdentity(sg, identityRelease("v0.28.2", hexOf('a'), hexOf('c')))
	if err != nil {
		t.Fatal(err)
	}
	if err = PublishSystemIdentity(ctx, s, pub, other); !errors.Is(err, ErrCASConflict) {
		t.Fatal("different release under the same tag accepted", err)
	}
}

func TestSignSystemIdentityRefusesWhatGuardArmCannotUse(t *testing.T) {
	_, key, _ := ed25519.GenerateKey(rand.Reader)
	sg := RootSigner(key)
	for name, mutate := range map[string]func(*SystemRelease){
		"no tag":       func(r *SystemRelease) { r.ReleaseTag = "" },
		"build as tag": func(r *SystemRelease) { r.ReleaseTag = "26065378" },
		"no protocol":  func(r *SystemRelease) { r.MovesProtocol = 0 },
		"bad router sha": func(r *SystemRelease) {
			r.Artifacts["linux-arm64"] = SystemArtifact{Key: SystemArtifactKey(r.Version, "linux-arm64"), SHA256: "abc"}
		},
		"bad console key": func(r *SystemRelease) {
			r.ConsoleArtifacts["linux-arm64"] = SystemArtifact{Key: "elsewhere", SHA256: hexOf('b')}
		},
		"no artifacts": func(r *SystemRelease) { r.Artifacts = nil },
	} {
		t.Run(name, func(t *testing.T) {
			rel := identityRelease("v0.28.2", hexOf('a'), hexOf('b'))
			mutate(&rel)
			if _, err := SignSystemIdentity(sg, rel); err == nil {
				t.Fatal("signed an identity guard-arm cannot use")
			}
		})
	}
	scoped := sg
	scoped.scope = &Grant{}
	if _, err := SignSystemIdentity(scoped, identityRelease("v0.28.2", hexOf('a'), hexOf('b'))); err == nil {
		t.Fatal("scoped key signed an identity")
	}
}

func hexOf(c byte) string {
	b := make([]byte, 64)
	for i := range b {
		b[i] = c
	}
	return string(b)
}