package layer

import (
	"context"
	"errors"
	"io"

	"git.frostfs.info/TrueCloudLab/frostfs-http-gw/utils"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/bearer"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container"
	cid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
	oid "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object/id"
)

// PrmContainer groups parameters of FrostFS.Container operation.
type PrmContainer struct {
	// Container identifier.
	ContainerID cid.ID
}

// PrmAuth groups authentication parameters for the FrostFS operation.
type PrmAuth struct {
	// Bearer token to be used for the operation. Overlaps PrivateKey. Optional.
	BearerToken *bearer.Token
}

// PrmObjectHead groups parameters of FrostFS.HeadObject operation.
type PrmObjectHead struct {
	// Authentication parameters.
	PrmAuth

	// Address to read the object header from.
	Address oid.Address
}

// PrmObjectGet groups parameters of FrostFS.GetObject operation.
type PrmObjectGet struct {
	// Authentication parameters.
	PrmAuth

	// Address to read the object header from.
	Address oid.Address
}

// PrmObjectRange groups parameters of FrostFS.RangeObject operation.
type PrmObjectRange struct {
	// Authentication parameters.
	PrmAuth

	// Address to read the object header from.
	Address oid.Address

	// Offset-length range of the object payload to be read.
	PayloadRange [2]uint64
}

// Object represents FrostFS object.
type Object struct {
	// Object header (doesn't contain payload).
	Header object.Object

	// Object payload part encapsulated in io.Reader primitive.
	// Returns ErrAccessDenied on read access violation.
	Payload io.ReadCloser
}

// PrmObjectCreate groups parameters of FrostFS.CreateObject operation.
type PrmObjectCreate struct {
	// Authentication parameters.
	PrmAuth

	Object *object.Object

	// Object payload encapsulated in io.Reader primitive.
	Payload io.Reader

	// Enables client side object preparing.
	ClientCut bool

	// Disables using Tillich-Zémor hash for payload.
	WithoutHomomorphicHash bool

	// Sets max buffer size to read payload.
	BufferMaxSize uint64
}

// PrmObjectSearch groups parameters of FrostFS.sear SearchObjects operation.
type PrmObjectSearch struct {
	// Authentication parameters.
	PrmAuth

	// Container to select the objects from.
	Container cid.ID

	Filters object.SearchFilters
}

type PrmInitMultiObjectReader struct {
	// payload range
	Off, Ln uint64

	Addr   oid.Address
	Bearer *bearer.Token
}

type ResObjectSearch interface {
	Read(buf []oid.ID) (int, error)
	Iterate(f func(oid.ID) bool) error
	Close()
}

var (
	// ErrAccessDenied is returned from FrostFS in case of access violation.
	ErrAccessDenied = errors.New("access denied")
	// ErrGatewayTimeout is returned from FrostFS in case of timeout, deadline exceeded etc.
	ErrGatewayTimeout = errors.New("gateway timeout")
	// ErrQuotaLimitReached is returned from FrostFS in case of quota exceeded.
	ErrQuotaLimitReached = errors.New("quota limit reached")
)

// FrostFS represents virtual connection to FrostFS network.
type FrostFS interface {
	Container(context.Context, PrmContainer) (*container.Container, error)
	HeadObject(context.Context, PrmObjectHead) (*object.Object, error)
	GetObject(context.Context, PrmObjectGet) (*Object, error)
	RangeObject(context.Context, PrmObjectRange) (io.ReadCloser, error)
	CreateObject(context.Context, PrmObjectCreate) (oid.ID, error)
	SearchObjects(context.Context, PrmObjectSearch) (ResObjectSearch, error)
	InitMultiObjectReader(ctx context.Context, p PrmInitMultiObjectReader) (io.Reader, error)

	utils.EpochInfoFetcher
}