package containerimageregistryclient

import (
	"bytes"
	"context"
	"crypto/sha256"
	"encoding/base64"
	"encoding/hex"
	"encoding/json"
	"io"
	"testing"

	seat "git.novox.be/novox/mesh-contracts/go/seats/containerimageregistry"
	"git.novox.be/novox/mesh-sdk/go/parts"
)

// The client publishes over its own seat's verbs alone (ADR 0627 §1): publish names every part, and only the part the
// holder lacks travels by publish-part, its bytes whole, the last chunk marked.
func TestPublishTalksToItsOwnSeat(t *testing.T) {
	held, lacked := []byte("held"), []byte("lacked")
	part := func(b []byte) parts.Part {
		sum := sha256.Sum256(b)
		return parts.Part{Digest: "sha256:" + hex.EncodeToString(sum[:]), Size: int64(len(b)),
			Open: func() (io.ReadCloser, error) { return io.NopCloser(bytes.NewReader(b)), nil }}
	}
	ps := []parts.Part{part(held), part(lacked)}
	var asked []string
	var got []byte
	call := func(key string, body any) (json.RawMessage, error) {
		asked = append(asked, key)
		raw, _ := json.Marshal(body)
		switch key {
		case "seat:container-image-registry.publish":
			var in seat.PublishInput
			_ = json.Unmarshal(raw, &in)
			if len(in.Parts) != 2 {
				t.Errorf("publish names %d parts, want 2", len(in.Parts))
			}
			return json.Marshal(seat.PublishAnswer{Transfer: in.Transfer, Lacks: []string{ps[1].Digest}})
		case "seat:container-image-registry.publish-part":
			var in seat.PublishPartInput
			_ = json.Unmarshal(raw, &in)
			data, _ := base64.StdEncoding.DecodeString(in.Data)
			if in.Part != ps[1].Digest || !in.Last || in.Transfer != "t1" {
				t.Errorf("publish-part %+v", in)
			}
			got = append(got, data...)
			return json.Marshal(seat.PublishPartAnswer{Transfer: in.Transfer, Part: in.Part})
		}
		t.Fatalf("asked %s", key)
		return nil, nil
	}
	sent, err := Publish(context.Background(), call, seat.PublishInput{Transfer: "t1", Name: "x"}, ps)
	if err != nil || sent.Transfer != "t1" || sent.Chunks != 1 || len(sent.Parts) != 1 || !bytes.Equal(got, lacked) || len(asked) != 2 {
		t.Errorf("sent %+v, %q arrived, asked %v, %v", sent, got, asked, err)
	}
}