import ApiRequestService from "./apiRequestService";
import {Repository, useRepo} from "pinia-orm";
import Url from "~/services/utils/url";
import ModelNormalizer from "./serializer/normalizer/modelNormalizer";
import HydraDenormalizer from "./serializer/denormalizer/hydraDenormalizer";
import ApiModel from "~/models/ApiModel";
import {useProfileAccessStore} from "~/store/profile/access";
import ApiResource from "~/models/ApiResource";
import {MyProfile} from "~/models/Access/MyProfile";
import { v4 as uuid4 } from 'uuid';
import {AssociativeArray, Collection} from "~/types/data.d";

/**
 * Entity manager: make operations on the models defined with the Pinia-Orm library
 *
 * @see https://pinia-orm.codedredd.de/
 */
class EntityManager {
    private CLONE_PREFIX = '_clone_'

    private apiRequestService: ApiRequestService;

    public constructor(apiRequestService: ApiRequestService) {
        this.apiRequestService = apiRequestService
    }

    /**
     * Return the repository for the model
     *
     * @param model
     */
    public getRepository(model: typeof ApiResource): Repository<ApiResource> {
        return useRepo(model)
    }

    /**
     * Create a new instance of the given model
     *
     * @param model
     * @param properties
     */
    public new(model: typeof ApiResource, properties: object = {}) {
        const repository = this.getRepository(model)

        const entity = repository.make(properties)

        // @ts-ignore
        if (!properties.hasOwnProperty('id') || !properties.id) {
            // Object has no id yet, we give him a temporary one
            entity.id = 'tmp' + uuid4()
        }
        repository.save(entity)

        this.saveInitialState(model, entity)

        return entity
    }

    /**
     * On met à jour directement l'entité par référence ou la liste d'entités,
     * pour maintenir la réactivité lorsque l'entité ou l'array est déclarée comme réactive
     *
     * Attention à ce que le sujet et la nouvelle valeur soient des objets de même type
     *
     * @see http://underscorejs.org/#extend
     * @param subject
     * @param newValue
     */
    public reactiveUpdate(subject: ApiResource | Array<ApiResource>, newValue: ApiResource | Array<ApiResource>) {
        if (typeof subject !== typeof newValue) { // TODO: remplacer par des règles typescript
            console.log('Error : subject and new value have to share the same type')
            return
        }
        if (Array.isArray(subject)) {
            this.reactiveUpdateArray(subject as Array<ApiResource>, newValue as Array<ApiResource>)
        } else {
            this.reactiveUpdateItem(subject as ApiResource, newValue as ApiResource)
        }
    }

    private reactiveUpdateItem(entity: ApiResource, newEntity: ApiResource) {
        useExtend(entity, newEntity)
    }

    private reactiveUpdateArray(items: Array<ApiResource>, newItems: Array<ApiResource>) {
        items.length = 0
        newItems.forEach((f: ApiResource) => {
            items.push(f)
        })
    }

    /**
     * Fetch an Entity / ApiResource by its id, save it to the store and returns it
     *
     * @param model  Model of the object to fetch
     * @param id   Id of the object to fetch
     * @param forceRefresh  Force a new get request to the api ;
     *                      current object in store will be overwritten if it exists
     */
    public async fetch(model: typeof ApiResource, id: number, forceRefresh: boolean = false): Promise<ApiResource> {

        const repository = this.getRepository(model)

        // If the entity is already in the store and forceRefresh is false, return the object in store
        if (!forceRefresh) {
            const item = repository.find(id)
            if (item && typeof item !== 'undefined') {
                return item
            }
        }

        // Else, get the object from the API
        const url = Url.join('api', model.entity, String(id))

        const response = await this.apiRequestService.get(url)

        // deserialize the response
        const attributes = HydraDenormalizer.denormalize(response).data as object

        return this.new(model, attributes)
    }

    public findBy(model: typeof ApiResource, query: AssociativeArray) {
        // TODO: implement
    }

    public async fetchAll(model: typeof ApiResource, page: number = 1): Promise<Collection> {
        let url = Url.join('api', model.entity)

        if (page !== 1) {
            url = Url.join(url, '?page=' + page)
        }
        console.log(url)

        const response = await this.apiRequestService.get(url)

        // deserialize the response
        const collection = HydraDenormalizer.denormalize(response)

        const items = collection.data.map((attributes: object) => {
            return this.new(model, attributes)
        })

        return {
            items,
            totalItems: collection.metadata.totalItems,
            firstPage: collection.metadata.firstPage,
            lastPage: collection.metadata.lastPage,
            nextPage: collection.metadata.nextPage,
            previousPage: collection.metadata.previousPage,
        }
    }

    /**
     * Persist the entity as it is in the store into the data source via the API
     *
     * @param model
     * @param entity
     */
    public async persist(model: typeof ApiModel, entity: ApiModel) {
        const repository = this.getRepository(model)

        let url = Url.join('api', model.entity)
        let response

        const data = ModelNormalizer.normalize(entity)

        if (!entity.isNew()) {
            url = Url.join(url, String(entity.id))
            response = await this.apiRequestService.put(url, data)
        } else {
            delete data.id
            response = await this.apiRequestService.post(url, data)
        }

        const hydraResponse = await HydraDenormalizer.denormalize(response)
        const returnedEntity = this.new(model, hydraResponse.data)

        this.saveInitialState(model, returnedEntity)

        // Save data into the store
        repository.save(returnedEntity)

        if (['accesses', 'organizations', 'parameters', 'subdomains'].includes(model.entity)) {
            await this.refreshProfile()
        }

        this.reactiveUpdate(entity, returnedEntity)
    }

    /**
     * Delete the entity from the datasource via the API
     *
     * @param model
     * @param entity
     */
    public async delete(model: typeof ApiModel, entity: ApiResource) {
        const repository = this.getRepository(model)

        // If object has been persisted to the datasource, send a delete request
        if (!entity.isNew()) {
            const url = Url.join('api', model.entity, String(entity.id))
            await this.apiRequestService.delete(url)
        }

        // reactiveUpdate the store
        repository.destroy(entity.id)
    }

    /**
     * Reset the entity to its initial state (i.e. the state it had when it was fetched from the API)
     *
     * @param model
     * @param entity
     */
    public reset(model: typeof ApiResource, entity: ApiResource) {
        const initialEntity = this.getInitialStateOf(model, entity.id)
        if (initialEntity === null) {
            throw new Error('no initial state recorded for this object - abort [' + model.entity + '/' + entity.id + ']')
        }

        const repository = this.getRepository(model)
        repository.save(initialEntity)

        this.reactiveUpdate(entity, initialEntity)
    }

    /**
     * Re-fetch the user profile and reactiveUpdate the store
     */
    public async refreshProfile() {
        const response = await this.apiRequestService.get('api/my_profile')

        // deserialize the response
        const hydraResponse = await HydraDenormalizer.denormalize(response)

        const profile = this.new(MyProfile, hydraResponse.data)

        const profileAccessStore = useProfileAccessStore()
        profileAccessStore.setProfile(profile)
    }

    /**
     * Delete all records in the repository of the model
     *
     * @param model
     */
    public async flush(model: typeof ApiModel) {
        const repository = this.getRepository(model)
        repository.flush()
    }

    /**
     * Is the entity a new one, or does it already exist in the data source (=API)
     *
     * @param model
     * @param id
     */
    public isNewEntity(model: typeof ApiModel, id: number | string): boolean {
        const repository = this.getRepository(model)

        const item = repository.find(id)
        if (!item || typeof item === 'undefined') {
            console.error(model.entity + '/' + id, ' does not exist!')
            return false
        }

        return item.isNew()
    }

    /**
     * Save the state of the entity in the store, so this state could be be restored later
     *
     * @param model
     * @param entity
     * @private
     */
    private saveInitialState(model: typeof ApiResource, entity: ApiResource) {
        const repository = this.getRepository(model)

        // Clone and prefix id
        const clone = useCloneDeep(entity)
        clone.id = this.CLONE_PREFIX + clone.id

        repository.save(clone)
    }

    /**
     * Return the saved state of the entity from the store
     *
     * @param model
     * @param id
     * @private
     */
    private getInitialStateOf(model: typeof ApiResource, id: string | number): ApiResource | null {
        const repository = this.getRepository(model)

        // Find the clone by id
        const entity = repository.find(this.CLONE_PREFIX + id)
        if (entity === null) {
            return null
        }

        // Restore the initial id
        entity.id = id
        return entity
    }
}

export default EntityManager