package storage

import (
	"bytes"
	"context"
	"io"
	"strings"
	"testing"
)

type fakeHostStorage struct {
	files map[string][]byte
}

func (s *fakeHostStorage) DefaultProvider(context.Context) (string, error) {
	return "system", nil
}

func (s *fakeHostStorage) Upload(
	_ context.Context,
	provider, key, _, _ string,
	_ int64,
	reader io.Reader,
) (string, error) {
	data, err := io.ReadAll(reader)
	if err != nil {
		return "", err
	}
	s.files[provider+":"+key] = data
	return "/files/" + key, nil
}

func (s *fakeHostStorage) Open(_ context.Context, provider, key string) (io.ReadCloser, error) {
	return io.NopCloser(bytes.NewReader(s.files[provider+":"+key])), nil
}

func (*fakeHostStorage) URL(_ context.Context, _ string, key string) (string, error) {
	return "/files/" + key, nil
}

func (s *fakeHostStorage) Delete(_ context.Context, provider, key string) error {
	delete(s.files, provider+":"+key)
	return nil
}

func TestHostStorageProvider(t *testing.T) {
	host := &fakeHostStorage{files: make(map[string][]byte)}
	SetHostStorage(host)
	t.Cleanup(func() { SetHostStorage(nil) })

	provider, err := GetDefault()
	if err != nil {
		t.Fatalf("GetDefault() error = %v", err)
	}
	if got := string(provider.ProviderType()); got != "system" {
		t.Fatalf("ProviderType() = %q, want system", got)
	}

	stored, err := provider.Upload(strings.NewReader("hello"), "chat/a.txt", UploadInfo{
		Filename: "a.txt",
		FileSize: 5,
		MimeType: "text/plain",
	})
	if err != nil {
		t.Fatalf("Upload() error = %v", err)
	}
	if stored.URL != "/files/chat/a.txt" {
		t.Fatalf("stored URL = %q", stored.URL)
	}

	reader, err := provider.Read("chat/a.txt")
	if err != nil {
		t.Fatalf("Read() error = %v", err)
	}
	defer reader.Close()
	data, err := io.ReadAll(reader)
	if err != nil || string(data) != "hello" {
		t.Fatalf("Read() = %q, %v", data, err)
	}

	if err = provider.Delete("chat/a.txt"); err != nil {
		t.Fatalf("Delete() error = %v", err)
	}
}