import path from 'path';
import * as plugins from './smartswagger.plugins';

interface RedocProps {
  'x-tagGroups'?: {name: string, tags: string[]}[];
}
type IExtendedApiDoc = plugins.openapiTypes.OpenAPIV3.Document & RedocProps;

export class Smartswagger {
  // STATIC
  /**
   * creates a new Smartswagger instance from an external document
   * @param urlArg a url arg that contains an original swagger.json in the response
   * @returns an instance of
   */
  public static async createFromUrl(urlArg: string) {
    const jsonResponse = await plugins.nodeFetch(urlArg, {
      headers: {
        accept: 'application/json',
      },
    });
    const apiDoc = await jsonResponse.json();
    const newSMartswaggerInstance = new Smartswagger(apiDoc);
    return newSMartswaggerInstance;
  }

  public static async createNew(titleArg: string = 'an OpenApiDoc') {
    const newSMartswaggerInstance = new Smartswagger({
      openapi: '3.0.0',
      paths: {},
      info: {
        title: titleArg,
        version: '1.0.0'
      }
    });
    return newSMartswaggerInstance;
  }

  // INSTANCE
  /**
   * the basic info of the api doc
   */
  public baseInfo: plugins.openapiTypes.OpenAPIV3.InfoObject;

  public apiDoc: IExtendedApiDoc;

  constructor(apiDocArg: IExtendedApiDoc) {
    this.apiDoc = apiDocArg;
  }

  /**
   * dereferences the document at hand
   */
  public async deref() {
    this.apiDoc = (await plugins.swaggerParser.dereference(this.apiDoc)) as IExtendedApiDoc;
  }

  public async addServer(serverArg: plugins.openapiTypes.OpenAPIV3.ServerObject) {
    await this.deref();
    this.apiDoc.servers = this.apiDoc.servers || [];
    this.apiDoc.servers.push(serverArg);
  }

  /**
   * merge a document from url
   * @param documentToMergeArg
   * @param basePathArg
   */
  public async mergeDocument(documentToMergeArg: IExtendedApiDoc, basePathArg: string = '', tagArg?: string) {
    console.log(`merging document with name ${documentToMergeArg.info?.title}`);
    await this.deref();
    // lets get a dereferenced version of the document we want to merge
    const documentToMerge = (await plugins.swaggerParser.dereference(
      documentToMergeArg
    )) as IExtendedApiDoc;
    for (const path of Object.keys(documentToMerge.paths)) {
      const pathToMerge = plugins.path.join(basePathArg, path);
      this.apiDoc.paths = this.apiDoc.paths || {};
      this.apiDoc.paths[pathToMerge] = documentToMerge.paths[path];
      if (tagArg) {
        if (this.apiDoc.paths[pathToMerge].post) {
          this.apiDoc.paths[pathToMerge].post.tags = this.apiDoc.paths[pathToMerge].post.tags || [];
          this.apiDoc.paths[pathToMerge].post.tags.push(tagArg);
        }
        if (this.apiDoc.paths[pathToMerge].get) {
          this.apiDoc.paths[pathToMerge].get.tags = this.apiDoc.paths[pathToMerge].get.tags || [];
          this.apiDoc.paths[pathToMerge].get.tags.push(tagArg);
        }
        if (this.apiDoc.paths[pathToMerge].put) {
          this.apiDoc.paths[pathToMerge].put.tags = this.apiDoc.paths[pathToMerge].put.tags || [];
          this.apiDoc.paths[pathToMerge].put.tags.push(tagArg);

        }
        if (this.apiDoc.paths[pathToMerge].delete) {
          this.apiDoc.paths[pathToMerge].delete.tags = this.apiDoc.paths[pathToMerge].delete.tags || [];
          this.apiDoc.paths[pathToMerge].delete.tags.push(tagArg);
        }

      }
    }

    // merge tag groups
    this.apiDoc['x-tagGroups'] = this.apiDoc['x-tagGroups'] || [];
    if (documentToMerge['x-tagGroups']) {
      for (const xTagGroup of documentToMerge['x-tagGroups']) {
        this.apiDoc['x-tagGroups'].push(xTagGroup);
      }
    }
    console.log('merged!');

    // set custom tag arg.
    if (tagArg) {
      this.apiDoc['x-tagGroups'].push({name: tagArg, tags: [tagArg]});
    }
  }

  /**
   * merges a document from url
   */
  public async mergeDocumentFromUrl(documentUrlArg: string, basePathArg: string = '', tagArg?: string) {
    console.log(`getting document at ${documentUrlArg} for merging...`);
    const documentResponse = await plugins.nodeFetch(documentUrlArg, {
      headers: {
        'accept-encoding': 'application/json',
      },
    }).catch(err => {
      console.log(err);
    });
    if (!documentResponse || documentResponse.status > 299) {
      return;
    }
    const documentString = await documentResponse.text();
    const apiDoc: IExtendedApiDoc = JSON.parse(documentString);
    console.log(`document successfully fetched!`);
    await this.mergeDocument(apiDoc, basePathArg, tagArg);
  }

  /**
   * merge multiple documents in parallel
   * @param urlArrayArg
   */
  public async mergeManyDocumentsFromUrl(urlArrayArg: { url: string; basePath?: string, tagArg?: string }[]) {
    const promiseArray: Promise<void>[] = [];
    for (const urlArg of urlArrayArg) {
      promiseArray.push(this.mergeDocumentFromUrl(urlArg.url, urlArg.basePath, urlArg.tagArg));
    }
    await Promise.all(promiseArray);
  }

  /**
   * merges a component to routes based on regex
   */
  public mergeComponentToRoutes(
    routeDescriptor: {
      includeGlobArray: string[];
      excludeGlobArray: string[];
    },
    componentArg: plugins.openapiTypes.OpenAPIV3.ComponentsObject
  ) {
    for (const pathCandidateRoute of Object.keys(this.apiDoc.paths)) {
      let included: boolean = false;
      let excluded: boolean = false;

      // We are using glob espressions here due to easier path expressions
      for (const globExpression of routeDescriptor.includeGlobArray) {
        if (plugins.matcher.isMatch(pathCandidateRoute, globExpression)) {
          included = true;
          break;
        }
      }
      if (included) {
        for (const globExpression of routeDescriptor.excludeGlobArray) {
          if (plugins.matcher.isMatch(pathCandidateRoute, globExpression)) {
            excluded = true;
            break;
          }
        }
      }
      if (included && !excluded) {
        // lets do the actual component inclusion
        const pathCandidate = this.apiDoc.paths[pathCandidateRoute];
        const instrumentMethod = (methodArg: typeof pathCandidate.get) => {
          if (!methodArg) {
            return;
          }
          if (componentArg.securitySchemes) {
            methodArg.security = methodArg.security || [];
            for (const securityScheme of Object.keys(componentArg.securitySchemes)) {
              methodArg.security.push({ [securityScheme]: [] })
            }
          }
        };
        instrumentMethod(pathCandidate.get);
        instrumentMethod(pathCandidate.post);
        instrumentMethod(pathCandidate.put);
        instrumentMethod(pathCandidate.delete);
      }
    }
  }

  private cacheResult: string = '';
  private cacheCreationUnixTimestamp: number;

  /**
   * returns an express middleware using 'swagger-ui-express'
   */
  public getSlashApiUiMiddleware() {
    return (req: plugins.smartexpress.Request, res: plugins.smartexpress.Response) => {
      res.setHeader('content-type', 'text/html');
      res.write(`
        <html>
          <head>
            <title>${this.apiDoc.info?.title || 'no name set'} - SwaggerUI</title>
            <link rel="stylesheet" type="text/css" href="https://unpkg.com/swagger-ui-dist@3.12.1/swagger-ui.css">
            <style>
              body {
                margin: 0px;
              }
            </style>
          </head>
          <body>
            <div id="swagger-ui"></div>
          </body>
          <script src="https://unpkg.com/swagger-ui-dist@3.12.1/swagger-ui-standalone-preset.js"></script>
          <script src="https://unpkg.com/swagger-ui-dist@3.12.1/swagger-ui-bundle.js"></script>
          <script>
            window.onload = function() {
              // Build a system
              const ui = SwaggerUIBundle({
                  url: "/apischema",
                  dom_id: '#swagger-ui',
                  deepLinking: true,
                  presets: [
                      SwaggerUIBundle.presets.apis,
                      SwaggerUIStandalonePreset
                  ],
                  plugins: [
                      SwaggerUIBundle.plugins.DownloadUrl
                  ],
                  layout: "StandaloneLayout",
              })
              window.ui = ui
            }
          </script>
        </html>
      `);
      res.end();
    };
  }

  public getSlashRedocMiddleware() {
    return (req: plugins.smartexpress.Request, res: plugins.smartexpress.Response) => {
      res.setHeader('content-type', 'text/html');
      res.write(`
        <html>
          <head>
            <title>${this.apiDoc.info?.title || 'no name set'} - Redoc </title>
            <!-- needed for adaptive design -->
            <meta charset="utf-8"/>
            <meta name="viewport" content="width=device-width, initial-scale=1">
            <link href="https://fonts.googleapis.com/css?family=Montserrat:300,400,700|Roboto:300,400,700" rel="stylesheet">
        
            <!--
            Redoc doesn't change outer page styles
            -->
            <style>
              body {
                margin: 0;
                padding: 0;
              }
            </style>
          </head>
          <body>
            <redoc spec-url='/apischema'></redoc>
            <script src="https://cdn.jsdelivr.net/npm/redoc@latest/bundles/redoc.standalone.js"> </script>
          </body>
        </html>
      `);
      res.end();
    };
  }

  public getSlashApiSchemaMiddleware() {
    return async (req: plugins.smartexpress.Request, res: plugins.smartexpress.Response) => {
      res.header('content-type', 'application/json');
      res.write(JSON.stringify(this.apiDoc));
      res.end();
    };
  }
}