import { VueConstructor } from 'vue'

import mimes from '@/libs/mimes'
import { has } from '@/libs/utils'
import fauxUploader from '@/libs/faux-uploader'
import rules from '@/validation/rules'
import messages from '@/validation/messages'
import merge from '@/utils/merge'

import FileUpload from '@/FileUpload'

import FormularioForm from '@/FormularioForm.vue'
import FormularioInput from '@/FormularioInput.vue'
import FormularioGrouping from '@/FormularioGrouping.vue'

import { ValidationContext, ValidationRule } from '@/validation/types'

interface FormularioOptions {
    components?: { [name: string]: VueConstructor };
    plugins?: any[];
    rules?: any;
    mimes?: any;
    uploader?: any;
    uploadUrl?: any;
    fileUrlKey?: any;
    uploadJustCompleteDuration?: any;
    validationMessages?: any;
    idPrefix?: string;
}

// noinspection JSUnusedGlobalSymbols
/**
 * The base formulario library.
 */
export default class Formulario {
    public options: FormularioOptions
    public idRegistry: { [name: string]: number }

    constructor () {
        this.options = {
            components: {
                FormularioForm,
                FormularioInput,
                FormularioGrouping,
            },
            rules,
            mimes,
            uploader: fauxUploader,
            uploadUrl: false,
            fileUrlKey: 'url',
            uploadJustCompleteDuration: 1000,
            validationMessages: messages,
            idPrefix: 'formulario-'
        }
        this.idRegistry = {}
    }

    /**
     * Install vue formulario, and register it’s components.
     */
    install (Vue: VueConstructor, options?: FormularioOptions): void {
        Vue.prototype.$formulario = this
        this.extend(options || {})
        for (const componentName in this.options.components) {
            if (has(this.options.components, componentName)) {
                Vue.component(componentName, this.options.components[componentName])
            }
        }
    }

    /**
     * Produce a deterministically generated id based on the sequence by which it
     * was requested. This should be *theoretically* the same SSR as client side.
     * However, SSR and deterministic ids can be very challenging, so this
     * implementation is open to community review.
     */
    nextId (vm: Vue): string {
        const options = this.options as FormularioOptions
        const path = vm.$route && vm.$route.path ? vm.$route.path : false
        const pathPrefix = path ? vm.$route.path.replace(/[/\\.\s]/g, '-') : 'global'
        if (!has(this.idRegistry, pathPrefix)) {
            this.idRegistry[pathPrefix] = 0
        }
        return `${options.idPrefix}${pathPrefix}-${++this.idRegistry[pathPrefix]}`
    }

    /**
     * Given a set of options, apply them to the pre-existing options.
     */
    extend (extendWith: FormularioOptions): Formulario {
        if (typeof extendWith === 'object') {
            this.options = merge(this.options, extendWith)
            return this
        }
        throw new Error(`VueFormulario extend() should be passed an object (was ${typeof extendWith})`)
    }

    /**
     * Get validation rules by merging any passed in with global rules.
     */
    rules (rules: Record<string, ValidationRule> = {}): () => Record<string, ValidationRule> {
        return { ...this.options.rules, ...rules }
    }

    /**
     * Get the validation message for a particular error.
     */
    validationMessage (rule: string, context: ValidationContext, vm: Vue): string {
        if (has(this.options.validationMessages, rule)) {
            return this.options.validationMessages[rule](vm, context)
        } else {
            return this.options.validationMessages.default(vm, context)
        }
    }

    /**
     * Get the file uploader.
     */
    getUploader (): any {
        return this.options.uploader || false
    }

    /**
     * Get the global upload url.
     */
    getUploadUrl (): string | boolean {
        return this.options.uploadUrl || false
    }

    /**
     * When re-hydrating a file uploader with an array, get the sub-object key to
     * access the url of the file. Usually this is just "url".
     */
    getFileUrlKey (): string {
        return this.options.fileUrlKey || 'url'
    }

    /**
     * Create a new instance of an upload.
     */
    createUpload (data: DataTransfer, context: Record<string, any>): FileUpload {
        return new FileUpload(data, context, this.options)
    }
}