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// Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
// @ts-check/// <reference path="../../core/internal.d.ts" />/// <reference path="../../core/lib.deno_core.d.ts" />/// <reference path="../web/internal.d.ts" />/// <reference path="../web/lib.deno_web.d.ts" />
"use strict";
((window) => {  const {    ArrayPrototypeIncludes,    Map,    MapPrototypeGet,    MapPrototypeHas,    MapPrototypeSet,    RegExpPrototypeTest,    StringPrototypeReplaceAll,    StringPrototypeToLowerCase,  } = window.__bootstrap.primordials;  const {    collectSequenceOfCodepoints,    HTTP_WHITESPACE,    HTTP_WHITESPACE_PREFIX_RE,    HTTP_WHITESPACE_SUFFIX_RE,    HTTP_QUOTED_STRING_TOKEN_POINT_RE,    HTTP_TOKEN_CODE_POINT_RE,    collectHttpQuotedString,  } = window.__bootstrap.infra;
  /**   * @typedef MimeType   * @property {string} type   * @property {string} subtype   * @property {Map<string,string>} parameters   */
  /**   * @param {string} input   * @returns {MimeType | null}   */  function parseMimeType(input) {    // 1.    input = StringPrototypeReplaceAll(input, HTTP_WHITESPACE_PREFIX_RE, "");    input = StringPrototypeReplaceAll(input, HTTP_WHITESPACE_SUFFIX_RE, "");
    // 2.    let position = 0;    const endOfInput = input.length;
    // 3.    const res1 = collectSequenceOfCodepoints(      input,      position,      (c) => c != "\u002F",    );    const type = res1.result;    position = res1.position;
    // 4.    if (type === "" || !RegExpPrototypeTest(HTTP_TOKEN_CODE_POINT_RE, type)) {      return null;    }
    // 5.    if (position >= endOfInput) return null;
    // 6.    position++;
    // 7.    const res2 = collectSequenceOfCodepoints(      input,      position,      (c) => c != "\u003B",    );    let subtype = res2.result;    position = res2.position;
    // 8.    subtype = StringPrototypeReplaceAll(subtype, HTTP_WHITESPACE_SUFFIX_RE, "");
    // 9.    if (      subtype === "" || !RegExpPrototypeTest(HTTP_TOKEN_CODE_POINT_RE, subtype)    ) {      return null;    }
    // 10.    const mimeType = {      type: StringPrototypeToLowerCase(type),      subtype: StringPrototypeToLowerCase(subtype),      /** @type {Map<string, string>} */      parameters: new Map(),    };
    // 11.    while (position < endOfInput) {      // 11.1.      position++;
      // 11.2.      const res1 = collectSequenceOfCodepoints(        input,        position,        (c) => ArrayPrototypeIncludes(HTTP_WHITESPACE, c),      );      position = res1.position;
      // 11.3.      const res2 = collectSequenceOfCodepoints(        input,        position,        (c) => c !== "\u003B" && c !== "\u003D",      );      let parameterName = res2.result;      position = res2.position;
      // 11.4.      parameterName = StringPrototypeToLowerCase(parameterName);
      // 11.5.      if (position < endOfInput) {        if (input[position] == "\u003B") continue;        position++;      }
      // 11.6.      if (position >= endOfInput) break;
      // 11.7.      let parameterValue = null;
      // 11.8.      if (input[position] === "\u0022") {        // 11.8.1.        const res = collectHttpQuotedString(input, position, true);        parameterValue = res.result;        position = res.position;
        // 11.8.2.        position++;      } else { // 11.9.        // 11.9.1.        const res = collectSequenceOfCodepoints(          input,          position,          (c) => c !== "\u003B",        );        parameterValue = res.result;        position = res.position;
        // 11.9.2.        parameterValue = StringPrototypeReplaceAll(          parameterValue,          HTTP_WHITESPACE_SUFFIX_RE,          "",        );
        // 11.9.3.        if (parameterValue === "") continue;      }
      // 11.10.      if (        parameterName !== "" &&        RegExpPrototypeTest(HTTP_TOKEN_CODE_POINT_RE, parameterName) &&        RegExpPrototypeTest(          HTTP_QUOTED_STRING_TOKEN_POINT_RE,          parameterValue,        ) &&        !MapPrototypeHas(mimeType.parameters, parameterName)      ) {        MapPrototypeSet(mimeType.parameters, parameterName, parameterValue);      }    }
    // 12.    return mimeType;  }
  /**   * @param {MimeType} mimeType   * @returns {string}   */  function essence(mimeType) {    return `${mimeType.type}/${mimeType.subtype}`;  }
  /**   * @param {MimeType} mimeType   * @returns {string}   */  function serializeMimeType(mimeType) {    let serialization = essence(mimeType);    for (const param of mimeType.parameters) {      serialization += `;${param[0]}=`;      let value = param[1];      if (!RegExpPrototypeTest(HTTP_TOKEN_CODE_POINT_RE, value)) {        value = StringPrototypeReplaceAll(value, "\\", "\\\\");        value = StringPrototypeReplaceAll(value, '"', '\\"');        value = `"${value}"`;      }      serialization += value;    }    return serialization;  }
  /**   * Part of the Fetch spec's "extract a MIME type" algorithm   * (https://fetch.spec.whatwg.org/#concept-header-extract-mime-type).   * @param {string[] | null} headerValues The result of getting, decoding and   * splitting the "Content-Type" header.   * @returns {MimeType | null}   */  function extractMimeType(headerValues) {    if (headerValues === null) return null;
    let charset = null;    let essence_ = null;    let mimeType = null;    for (const value of headerValues) {      const temporaryMimeType = parseMimeType(value);      if (        temporaryMimeType === null ||        essence(temporaryMimeType) == "*/*"      ) {        continue;      }      mimeType = temporaryMimeType;      if (essence(mimeType) !== essence_) {        charset = null;        const newCharset = MapPrototypeGet(mimeType.parameters, "charset");        if (newCharset !== undefined) {          charset = newCharset;        }        essence_ = essence(mimeType);      } else {        if (          !MapPrototypeHas(mimeType.parameters, "charset") &&          charset !== null        ) {          MapPrototypeSet(mimeType.parameters, "charset", charset);        }      }    }    return mimeType;  }
  window.__bootstrap.mimesniff = {    parseMimeType,    essence,    serializeMimeType,    extractMimeType,  };})(this);