import Observable from "./observable";
import Lock from "./lock";

export interface IFileVersion {
   version: string;
   time: Date;
   preview: string;
   deleted: boolean;
}

export interface IFile {
   _id: string;
   type: string;
   name: string;
   folder: string;
   deleted: boolean;
   active: IFileVersion;
   versions: IFileVersion[];
   user: string;
   application: string;
}

export interface IHistory {
   file: IFile;
   history: IFileVersion[];
}


export class NoConnection extends Error {
   type: string;
   constructor() {
      super("No connection");
      this.type = "noconnection"
   }
}

export class Unauthorized extends Error {
   type: string;
   constructor() {
      super("Not authorized");
      this.type = "unauthorized"
   }
}

export class NoPermission extends Error {
   type: string;
   constructor() {
      super("No permission");
      this.type = "nopermission"
   }
}

export class NotFound extends Error {
   type: string;
   constructor() {
      super("Not found");
      this.type = "notfound"
   }
}

export class BadRequest extends Error {
   type: string;
   constructor() {
      super("Bad request");
      this.type = "badrequest"
   }
}

import * as fetch from "isomorphic-fetch";

function statusParser(res: Response) {
   if (res.status !== 200) {
      switch (res.status) {
         case 400:
            throw new BadRequest();
         case 404:
            throw new NotFound();
         case 403:
            throw new NoPermission();
         case 401:
            throw new Unauthorized();
         default:
            throw new Error(res.statusText);
      }
   }
}

export default class SecureFileWrapper {
   private _jwtObservableServer: Observable<(jwt: string) => void> = new Observable();
   jwtObservable = this._jwtObservableServer.getPublicApi();

   jwt: string;

   auth_lock = new Lock();

   constructor(private server: string) {
      if (this.server.endsWith("/")) {
         this.server += "api/v1";
      } else {
         this.server += "/api/v1";
      }
   }

   public async getJWT() {
      if (!this.auth_lock.locked) {
         let lock = await this.auth_lock.getLock();
         this._jwtObservableServer.send((jwt: string) => {
            this.jwt = jwt;
            lock.release();
         });
      }

      await this.auth_lock.getLock().then(lock => lock.release())
   }

   public async makeRequest(endpoint: string, method: "POST" | "GET" | "PUT" | "DELETE", query: any, body?: ArrayBuffer | ArrayBufferView, second = false) {
      if (!this.jwt || this.jwt === undefined) {
         await this.getJWT();
      }

      query.jwt = this.jwt;
      let query_str = "?";
      let first = true;
      for (let key in query) {
         if (!first) query_str += "&";
         query_str += encodeURIComponent(key) + "=" + encodeURIComponent(query[key]);
         first = false;
      }
      var headers = {
         "pragme": "no-cache",
         "cache-control": "no-cache"
      };

      let body_n;
      if (body) {
         headers["Content-Type"] = "application/octet-stream"
         body_n = Buffer ? Buffer.from(body instanceof ArrayBuffer ? body : body.buffer) : body;
      }
      try {
         let res = await fetch(this.server + endpoint + query_str, { method, body: body_n, headers });
         if (res.status === 401 && !second) {
            await this.getJWT();
            return this.makeRequest(endpoint, method, query, body, true);
         } else {
            statusParser(res);
            return res;
         }
      } catch (err) {
         if (err instanceof TypeError || err.errno === "ECONNREFUSED")
            throw new NoConnection();
         throw err;
      }
   }

   // async test(jwt): Promise<{ user: string, test: true }> {
   //    let res = await this.makeRequest("/test", "GET", {}, undefined, this.jwt_enabled);
   //    statusParser(res);
   //    return await res.json();
   // }

   async list(folder?: string): Promise<IFile[]> {
      let query: any = {}
      if (folder) query.folder = folder;
      let res = await this.makeRequest("/files", "GET", query);
      let d = await res.json();
      return d.files;
   }

   async create(name: string, data: ArrayBuffer | ArrayBufferView, type: "text" | "binary", folder?: string, preview?: string): Promise<IFile> {
      let params: any = { type: type, name: name };
      if (preview) {
         params.preview = preview;
      }
      if (folder) {
         params.folder = folder;
      }

      let res = await this.makeRequest("/files", "POST", params, data);
      return (await res.json()).file;
   }

   async get(id: string, version?: string): Promise<ArrayBuffer> {
      let res: Response;
      if (typeof version === "string") {
         res = await this.makeRequest(`/files/${id}/history/${version}`, "GET", {});
      } else {
         res = await this.makeRequest("/files/" + id, "GET", {});
      }

      if (res.arrayBuffer) {
         return res.arrayBuffer()
      } else {
         let blob: Buffer = await (<any>res).buffer()
         // console.log(blob.length);
         return Uint8Array.from(blob).buffer;
      }
   }

   async update(id: string, data: ArrayBuffer | ArrayBufferView, preview?: string): Promise<IFile> {
      let put: any = {};
      if (preview) put.preview = preview;
      let res = await this.makeRequest("/files/" + id, "PUT", put, data);

      let json = await res.json()
      return json.file;
   }

   async delete(id: string): Promise<boolean> {
      let res = await this.makeRequest("/files/" + id, "DELETE", {});

      return res.json();
   }

   async history(id: string): Promise<IHistory> {
      let res = await this.makeRequest(`/files/${id}/history`, "GET", {});
      statusParser(res);
      return res.json();
   }

   async restore(id: string, version: string) {
      await this.makeRequest(`/files/${id}/history/${version}/restore`, "PUT", {});
   }
}