import {Injectable, ScopedContainer, Container} from "@extollo/di"
import {infer} from "@extollo/util"
import {IncomingMessage, ServerResponse} from "http"
import {HTTPCookieJar} from "../kernel/HTTPCookieJar";
import {TLSSocket} from "tls";
import * as url from "url";
import {Response} from "./Response";
import * as Negotiator from "negotiator";

// FIXME - add others?
export type HTTPMethod = 'post' | 'get' | 'patch' | 'put' | 'delete' | 'unknown';
export function isHTTPMethod(what: any): what is HTTPMethod {
    return ['post', 'get', 'patch', 'put', 'delete'].includes(what)
}

export interface HTTPProtocol {
    string: string,
    major: number,
    minor: number,
}

export interface HTTPSourceAddress {
    address: string;
    family: 'IPv4' | 'IPv6';
    port: number;
}

@Injectable()
export class Request extends ScopedContainer {

    public readonly cookies: HTTPCookieJar;

    public readonly url: string;
    public readonly fullUrl: string;
    public readonly method: HTTPMethod;
    public readonly secure: boolean;
    public readonly protocol: HTTPProtocol;
    public readonly path: string;
    public readonly rawQueryData: {[key: string]: string | string[] | undefined};
    public readonly query: {[key: string]: any};
    public readonly isXHR: boolean;
    public readonly address: HTTPSourceAddress;
    public readonly response: Response;
    public readonly mediaTypes: string[];

    constructor(
        protected clientRequest: IncomingMessage,
        protected serverResponse: ServerResponse,
    ) {
        super(Container.getContainer())

        this.secure = !!(clientRequest.connection as TLSSocket).encrypted

        this.cookies = new HTTPCookieJar(this)
        this.url = String(clientRequest.url)
        this.fullUrl = (this.secure ? 'https' : 'http') + `://${this.getHeader('host')}${this.url}`

        const method = clientRequest.method?.toLowerCase()
        this.method = isHTTPMethod(method) ? method : 'unknown'

        this.protocol = {
            string: clientRequest.httpVersion,
            major: clientRequest.httpVersionMajor,
            minor: clientRequest.httpVersionMinor,
        }

        this.register(Request)
        this.instances.push({
            key: Request,
            value: this,
        })

        const parts = url.parse(this.url, true)

        this.path = parts.pathname ?? '/'
        this.rawQueryData = parts.query

        const query: {[key: string]: any} = {}
        for ( const key in this.rawQueryData ) {
            const value = this.rawQueryData[key]

            if ( Array.isArray(value) ) {
                query[key] = value.map(x => infer(x))
            } else if ( value ) {
                query[key] = infer(value)
            } else {
                query[key] = value
            }
        }

        this.query = query
        this.isXHR = String(this.clientRequest.headers['x-requested-with']).toLowerCase() === 'xmlhttprequest'

        // @ts-ignore
        const {address = '0.0.0.0', family = 'IPv4', port = 0} = this.clientRequest.connection.address()
        this.address = {
            address,
            family,
            port
        }

        this.mediaTypes = (new Negotiator(clientRequest)).mediaTypes()
        this.response = new Response(this, serverResponse)
    }

    public getHeader(name: string) {
        return this.clientRequest.headers[name.toLowerCase()]
    }

    public toNative() {
        return this.clientRequest
    }

    public input(key: string) {
        if ( key in this.query ) {
            return this.query[key]
        }
    }

    accepts(type: string) {
        if ( type === 'json' ) type = 'application/json'
        else if ( type === 'xml' ) type = 'application/xml'
        else if ( type === 'html' ) type = 'text/html'

        type = type.toLowerCase()

        const possible = [
            type,
            type.split('/')[0] + '/*',
            '*/*'
        ]

        return this.mediaTypes.some(media => possible.includes(media.toLowerCase()))
    }

    wants(): 'html' | 'json' | 'xml' | 'unknown' {
        const jsonIdx = this.mediaTypes.indexOf('application/json') ?? this.mediaTypes.indexOf('application/*') ?? this.mediaTypes.indexOf('*/*')
        const xmlIdx = this.mediaTypes.indexOf('application/xml') ?? this.mediaTypes.indexOf('application/*') ?? this.mediaTypes.indexOf('*/*')
        const htmlIdx = this.mediaTypes.indexOf('text/html') ?? this.mediaTypes.indexOf('text/*') ?? this.mediaTypes.indexOf('*/*')

        if ( htmlIdx >= 0 && htmlIdx <= jsonIdx && htmlIdx <= xmlIdx ) return 'html'
        if ( jsonIdx >= 0 && jsonIdx <= htmlIdx && jsonIdx <= xmlIdx ) return 'json'
        if ( xmlIdx >= 0 && xmlIdx <= jsonIdx && xmlIdx <= htmlIdx ) return 'xml'
        return 'unknown'
    }

    // hostname

    /*
    param
    json
    fresh/stale - cache
    remote ips (proxy)
    signedCookies
    accepts charsets, encodings, languages
    range header parser
     */
}