package logic

import (
	"context"

	"spark-server/internal/module/friend/entity"
	msgentity "spark-server/internal/module/message/entity"
	userentity "spark-server/internal/module/user/entity"
)

// Repository is friend persistence. Model implements it; do not split this by table.
type Repository interface {
	GetRelation(ctx context.Context, a, b int64) (*entity.Relation, error)
	ListFriends(ctx context.Context, userID int64, limit int) ([]*entity.Relation, error)
	GetRequest(ctx context.Context, id int64) (*entity.Request, error)
	GetRequestByPair(ctx context.Context, from, to int64) (*entity.Request, error)
	UpsertRequest(ctx context.Context, req *entity.Request) error
	ListIncoming(ctx context.Context, toUserID int64, status, limit int) ([]*entity.Request, error)
	GetRemark(ctx context.Context, userID, friendID int64) (string, error)
	ListRemarks(ctx context.Context, userID int64, friendIDs []int64) (map[int64]string, error)
	SetRemark(ctx context.Context, userID, friendID int64, remark string) error
	IsBlocked(ctx context.Context, userID, targetID int64) (bool, error)
	BlockedEither(ctx context.Context, a, b int64) (bool, error)
	CreateBlock(ctx context.Context, b *entity.Block) error
	DeleteBlock(ctx context.Context, userID, blockedID int64) error
	CreateReport(ctx context.Context, r *entity.Report) error
	AcceptFriend(ctx context.Context, in entity.AcceptParams) error
	DeleteFriend(ctx context.Context, a, b int64) error
}

// UserFinder resolves accounts by uid / email / spark_id / qrcode ticket.
type UserFinder interface {
	Get(ctx context.Context, id int64) (*userentity.User, error)
	GetByEmail(ctx context.Context, email string) (*userentity.User, error)
	GetBySparkID(ctx context.Context, sparkID string) (*userentity.User, error)
	GetByQRCode(ctx context.Context, qrcode string) (*userentity.User, error)
}

// IDGen issues Snowflake ids for requests, reports, and system messages.
type IDGen interface {
	NextID() (int64, error)
}

// Greeter writes the "became friends" system message. Nil skips greeting.
type Greeter interface {
	BecameFriends(ctx context.Context, userA, userB int64) error
}

// P2PChats opens (or reuses) the 1:1 conversation for a pair.
type P2PChats interface {
	EnsureP2P(ctx context.Context, userA, userB int64) (int64, error)
	UpdateLastMsg(ctx context.Context, conversationID, msgID, atMS int64) error
}

// Messages persists a row in messages.
type Messages interface {
	Create(ctx context.Context, m *msgentity.Message) error
}

// Service is the friend use-case layer (HTTP and TCP share it).
type Service struct {
	repo    Repository
	users   UserFinder
	ids     IDGen
	greeter Greeter
}

func NewService(repo Repository, users UserFinder, ids IDGen, greeter Greeter) *Service {
	return &Service{repo: repo, users: users, ids: ids, greeter: greeter}
}

func (s *Service) ready() bool {
	return s != nil && s.repo != nil && s.users != nil && s.ids != nil
}