package utils

import (
	"crypto/sha256"
	"encoding/json"
	"errors"
	"slices"
	"time"

	"cloud.o-forge.io/core/oc-lib/dbs"
	"cloud.o-forge.io/core/oc-lib/tools"
	"github.com/go-playground/validator/v10"
	"github.com/google/uuid"
	"github.com/rs/zerolog"
)

// single instance of the validator used in every model Struct to validate the fields
var validate = validator.New(validator.WithRequiredStructEnabled())

type AccessMode int

const (
	Private AccessMode = iota
	Public
)

/*
* AbstractObject is a struct that represents the basic fields of an object
* it defines the object id and name
* every data in base root model should inherit from this struct (only exception is the ResourceModel)
 */
type AbstractObject struct {
	UUID          string     `json:"id,omitempty" bson:"id,omitempty" validate:"required"`
	Name          string     `json:"name,omitempty" bson:"name,omitempty" validate:"required"`
	IsDraft       bool       `json:"is_draft" bson:"is_draft" default:"false"`
	CreatorID     string     `json:"creator_id,omitempty" bson:"creator_id,omitempty"`
	UserCreatorID string     `json:"user_creator_id,omitempty" bson:"user_creator_id,omitempty"`
	CreationDate  time.Time  `json:"creation_date,omitempty" bson:"creation_date,omitempty"`
	UpdateDate    time.Time  `json:"update_date,omitempty" bson:"update_date,omitempty"`
	UpdaterID     string     `json:"updater_id,omitempty" bson:"updater_id,omitempty"`
	UserUpdaterID string     `json:"user_updater_id,omitempty" bson:"user_updater_id,omitempty"`
	AccessMode    AccessMode `json:"access_mode" bson:"access_mode" default:"0"`
	Signature     []byte     `bson:"signature,omitempty" json:"signature,omitempty"`
}

func (ri *AbstractObject) GetAccessor(request *tools.APIRequest) Accessor {
	return nil
}

func (r *AbstractObject) Unsign() {
	r.Signature = nil
}

func (r *AbstractObject) Sign() {
	priv, err := tools.LoadKeyFromFilePrivate() // your node private key
	if err != nil {
		return
	}
	b, _ := json.Marshal(r.DeepCopy())
	hash := sha256.Sum256(b)
	r.Signature, err = priv.Sign(hash[:])
}

func (r *AbstractObject) SetID(id string) {
	r.UUID = id
}

func (r *AbstractObject) DeepCopy() *AbstractObject {
	var obj AbstractObject
	b, err := json.Marshal(r)
	if err != nil {
		return nil
	}
	if err := json.Unmarshal(b, &obj); err != nil {
		return nil
	}
	return &obj
}

func (r *AbstractObject) SetName(name string) {
	r.Name = name
}

func (r *AbstractObject) GenerateID() {
	if r.UUID == "" {
		r.UUID = uuid.New().String()
	}
}

func (r *AbstractObject) StoreDraftDefault() {
	r.IsDraft = false
}

func (r *AbstractObject) CanUpdate(set DBObject) (bool, DBObject) {
	return true, set
}

func (r *AbstractObject) CanDelete() bool {
	return true
}

func (r *AbstractObject) IsDrafted() bool {
	return r.IsDraft
}

// GetID implements ShallowDBObject.
func (ao AbstractObject) GetID() string {
	return ao.UUID
}

func (ao AbstractObject) GetSignature() []byte {
	return ao.Signature
}

// GetName implements ShallowDBObject.
func (ao AbstractObject) GetName() string {
	return ao.Name
}

func (ao *AbstractObject) GetCreatorID() string {
	return ao.CreatorID
}

func (ao *AbstractObject) UpToDate(user string, peer string, create bool) {
	ao.UpdateDate = time.Now()
	ao.UpdaterID = peer
	ao.UserUpdaterID = user
	if create && ao.CreatorID != "" {
		ao.CreationDate = time.Now()
		ao.CreatorID = peer
		ao.UserCreatorID = user
	}
}

func (ao *AbstractObject) VerifyAuth(callName string, request *tools.APIRequest) bool {
	return (ao.AccessMode == Public && callName == "get") || (request != nil && (request.Admin || (ao.CreatorID == request.PeerID && request.PeerID != "")))
}

// TODO : check write per auth

func (ao *AbstractObject) GetObjectFilters(search string) *dbs.Filters {
	if search == "*" {
		search = ""
	}
	return &dbs.Filters{
		Or: map[string][]dbs.Filter{ // filter by name if no filters are provided
			"abstractobject.name": {{Operator: dbs.LIKE.String(), Value: search}},
		}}
}

func (dma *AbstractObject) Deserialize(j map[string]interface{}, obj DBObject) DBObject {
	b, err := json.Marshal(j)
	if err != nil {
		return nil
	}
	json.Unmarshal(b, obj)
	return obj
}

func (dma *AbstractObject) Serialize(obj DBObject) map[string]interface{} {
	var m map[string]interface{}
	b, err := json.Marshal(obj)
	if err != nil {
		return nil
	}
	json.Unmarshal(b, &m)
	return m
}

type AbstractAccessor[T DBObject] struct {
	Logger                zerolog.Logger    // Logger is the logger of the accessor, it's a specilized logger for the accessor
	Type                  tools.DataType    // Type is the data type of the accessor
	Request               *tools.APIRequest // Caller is the http caller of the accessor (optionnal) only need in a peer connection
	ResourceModelAccessor Accessor
	New                   func() T
	NotImplemented        []string
}

func (r *AbstractAccessor[T]) ShouldVerifyAuth() bool {
	return true
}

func (r *AbstractAccessor[T]) GetRequest() *tools.APIRequest {
	return r.Request
}

func (dma *AbstractAccessor[T]) GetUser() string {
	if dma.Request == nil {
		return ""
	}
	return dma.Request.Username
}

func (dma *AbstractAccessor[T]) GetPeerID() string {
	if dma.Request == nil {
		return ""
	}
	return dma.Request.PeerID
}
func (dma *AbstractAccessor[T]) GetGroups() []string {
	if dma.Request == nil {
		return []string{}
	}
	return dma.Request.Groups
}
func (dma *AbstractAccessor[T]) GetLogger() *zerolog.Logger {
	return &dma.Logger
}
func (dma *AbstractAccessor[T]) GetType() tools.DataType {
	return dma.Type
}

func (dma *AbstractAccessor[T]) GetCaller() *tools.HTTPCaller {
	if dma.Request == nil {
		return nil
	}
	return dma.Request.Caller
}

/*
* Nothing special here, just the basic CRUD operations
 */
func (a *AbstractAccessor[T]) DeleteOne(id string) (DBObject, int, error) {
	if len(a.NotImplemented) > 0 && slices.Contains(a.NotImplemented, "DeleteOne") {
		return nil, 404, errors.New("not implemented")
	}
	return GenericDeleteOne(id, a)
}

func (a *AbstractAccessor[T]) UpdateOne(set DBObject, id string) (DBObject, int, error) {
	if len(a.NotImplemented) > 0 && slices.Contains(a.NotImplemented, "UpdateOne") {
		return nil, 404, errors.New("not implemented")
	}
	// should verify if a source is existing...
	return GenericUpdateOne(set, id, a, a.New())
}

func (a *AbstractAccessor[T]) StoreOne(data DBObject) (DBObject, int, error) {
	if len(a.NotImplemented) > 0 && slices.Contains(a.NotImplemented, "StoreOne") {
		return nil, 404, errors.New("not implemented")
	}
	return GenericStoreOne(data.(T), a)
}

func (a *AbstractAccessor[T]) CopyOne(data DBObject) (DBObject, int, error) {
	if len(a.NotImplemented) > 0 && slices.Contains(a.NotImplemented, "CopyOne") {
		return nil, 404, errors.New("not implemented")
	}
	return GenericStoreOne(data.(T), a)
}

func (a *AbstractAccessor[T]) LoadOne(id string) (DBObject, int, error) {
	return GenericLoadOne[T](id, func(d DBObject) (DBObject, int, error) {
		return d, 200, nil
	}, a)
}

func (a *AbstractAccessor[T]) LoadAll(isDraft bool) ([]ShallowDBObject, int, error) {
	return GenericLoadAll[T](a.GetExec(isDraft), isDraft, a)
}

func (a *AbstractAccessor[T]) Search(filters *dbs.Filters, search string, isDraft bool) ([]ShallowDBObject, int, error) {
	return GenericSearch[T](filters, search, a.New().GetObjectFilters(search), a.GetExec(isDraft), isDraft, a)
}

func (a *AbstractAccessor[T]) GetExec(isDraft bool) func(DBObject) ShallowDBObject {
	return func(d DBObject) ShallowDBObject {
		return d
	}
}