package dbreads

import (
	"bytes"
	"encoding/json"
	"testing"
)

// Each line carries exactly one outcome, and a full-size sealed chunk fits
// MaxLineBytes once base64-encoded.
func TestLinesAreOneOutcomeEach(t *testing.T) {
	t.Parallel()
	for _, l := range []Line{
		{Admitted: "dbr_aaaaaaaaaaaaaaaaaaaaaaaaaa"},
		{Picked: "uk-1"},
		{Chunk: 1, Data: []byte("sealed")},
		{Wait: WaitPickup},
		{Ended: EndedNotPicked},
		{Result: &Result{State: StateDone, LastSeq: 1}},
	} {
		b, err := json.Marshal(l)
		if err != nil {
			t.Fatal(err)
		}
		var m map[string]any
		if err := json.Unmarshal(b, &m); err != nil {
			t.Fatal(err)
		}
		keys := len(m)
		if l.Chunk != 0 {
			keys-- // a chunk line is two fields, chunk and data
		}
		if keys != 1 {
			t.Fatalf("%s carries %d outcomes", b, keys)
		}
	}
	full, _ := json.Marshal(Line{Chunk: 1, Data: bytes.Repeat([]byte{0xff}, ChunkBytes+SealOverhead)})
	if len(full)+1 > MaxLineBytes {
		t.Fatalf("a full chunk line is %d bytes, over MaxLineBytes", len(full))
	}
}

// A full pull chunk, sealed and base64-encoded in its line, fits
// MaxLineBytes (plan 3: a 1 MiB chunk's line is about 1.4 MB).
func TestAFullPullChunkLineFits(t *testing.T) {
	t.Parallel()
	full, _ := json.Marshal(Line{Chunk: 1, Data: bytes.Repeat([]byte{0xff}, PullChunkBytes+SealOverhead)})
	if len(full)+1 > MaxLineBytes {
		t.Fatalf("a full pull chunk line is %d bytes", len(full))
	}
}