package mic

import (
	"bytes"
	"os"
	"testing"
)

func TestRecorderCloseIdempotent(t *testing.T) {
	t.Parallel()
	dir := t.TempDir()
	path := dir + "/rec.wav"
	// openRecorder uses MicDir(); write through fileRecorder directly.
	f, err := os.Create(path)
	if err != nil {
		t.Fatal(err)
	}
	r := &fileRecorder{path: path, f: f}
	if err := r.Write([]byte{1, 0, 2, 0}); err != nil {
		t.Fatal(err)
	}
	n, err := r.Close()
	if err != nil {
		t.Fatal(err)
	}
	if n != 4 {
		t.Fatalf("written = %d, want 4", n)
	}
	n2, err := r.Close()
	if err != nil {
		t.Fatal(err)
	}
	if n2 != 4 {
		t.Fatalf("second close written = %d, want 4", n2)
	}
	if err := r.Write([]byte{3, 0}); err == nil {
		t.Fatal("write after close should fail")
	}
}

func TestAppendChunkPCMCaps(t *testing.T) {
	t.Parallel()
	half := maxChunkPCM / 2
	buf := appendChunkPCM(nil, bytes.Repeat([]byte{1}, half))
	buf = appendChunkPCM(buf, bytes.Repeat([]byte{2}, half))
	buf = appendChunkPCM(buf, bytes.Repeat([]byte{3}, half))
	if len(buf) != maxChunkPCM {
		t.Fatalf("len = %d, want %d", len(buf), maxChunkPCM)
	}
	if buf[0] != 2 {
		t.Fatalf("first byte = %d, want 2 (oldest chunk dropped)", buf[0])
	}
}