package mgocrud

import (
	"errors"

	"gopkg.in/mgo.v2/bson"
)

var (
	ErrNotFound = errors.New("not found")
)

type Connection interface {
	Close()
	NewSession() Session
}

type Session interface {
	Connection() Connection
	Close()
	DB(name string) Database
}

type Database interface {
	Session() Session
	// C(name string) Collection
	Name() string
	EnsureIndex(m ModelInterface, index ...Index) error
	ReadDocument(m ModelInterface, selector bson.M) error
	CreateDocument(m ModelInterface) error
	ReadCollection(results interface{}, filter bson.M, selector bson.M, offset int, limit int, sort []string, pipelineModifier PipelineModifierFunction) error
	ReadCollectionCount(m ModelInterface, filter bson.M) (count int, err error)
	UpdateDocument(m ModelInterface, changes bson.M) error
	UpsertDocument(m ModelInterface, changes bson.M) error
	DeleteDocument(m ModelInterface) error
	DeleteDocuments(m ModelInterface, filter bson.M) (removed int, err error)
}

type Collection interface {
	DB() Database
	Insert(docs ...interface{}) error
	UpdateId(id interface{}, update interface{}) error
	RemoveId(id interface{}) error
	Upsert(selector interface{}, update interface{}) (ChangeInfo, error)
	RemoveAll(filter interface{}) (ChangeInfo, error)
	FindId(id interface{}) Query
	Find(query interface{}) Query
	EnsureIndex(index Index) error
	Pipe(pipeline interface{}) Pipe
}

type ChangeInfo interface {
	Matched() int
	Removed() int
	Updated() int
}

type Query interface {
	Select(selector interface{}) Query
	One(result interface{}) error
	Sort(fields ...string) Query
	Skip(n int) Query
	Limit(n int) Query
	All(result interface{}) error
	Count() (int, error)
}

type Index interface{}

type Pipe interface {
	All(result interface{}) error
}