package storage

import (
	"context"
	"time"
)

// ObjectStore is a remote object storage boundary used by prepare, restore, and publish work.
//
// Key invariant:
// callers pass full bucket-relative object keys. Backend implementations do not
// infer Narratio session semantics and do not prepend root prefixes.
type ObjectStore interface {
	List(ctx context.Context, prefix string) ([]ObjectInfo, error)
	Download(ctx context.Context, key, localPath string) error
	Upload(ctx context.Context, localPath, key string, opts UploadOptions) (ObjectInfo, error)
	Exists(ctx context.Context, key string) (bool, error)
}

// ObjectInfo describes one object in remote storage.
type ObjectInfo struct {
	Key          string
	Size         int64
	ETag         string
	LastModified *time.Time
}

// UploadOptions configures optional object upload metadata.
type UploadOptions struct {
	Metadata    map[string]string
	ContentType string
}