"use strict";
var __importDefault = (this && this.__importDefault) || function (mod) {
    return (mod && mod.__esModule) ? mod : { "default": mod };
};
Object.defineProperty(exports, "__esModule", { value: true });
const labels_1 = __importDefault(require("./labels"));
const buffer_1 = require("../../utils/buffer");
const builtin_header_names_1 = __importDefault(require("../../request-pipeline/builtin-header-names"));
const CHARSET_RE = /(?:^|;)\s*charset=(.+)(?:;|$)/i;
const META_CHARSET_RE = /charset ?= ?['"]?([^ ;"']*)['"]?/i;
// NOTE: HTTP 1.1 specifies ISO-8859-1 as the default charset
// (see: http://www.w3.org/International/O-HTTP-charset.en.php).
const DEFAULT_CHARSET = 'iso-8859-1';
const CHARSET_BOM_LIST = [
    {
        charset: 'utf-8',
        bom: Buffer.from([0xEF, 0xBB, 0xBF]),
    },
    {
        charset: 'utf-16le',
        bom: Buffer.from([0xFF, 0xFE]),
    },
    {
        charset: 'utf-16be',
        bom: Buffer.from([0xFE, 0xFF]),
    },
];
var CharsetPriority;
(function (CharsetPriority) {
    CharsetPriority[CharsetPriority["BOM"] = 3] = "BOM";
    CharsetPriority[CharsetPriority["CONTENT_TYPE"] = 2] = "CONTENT_TYPE";
    CharsetPriority[CharsetPriority["URL"] = 1] = "URL";
    CharsetPriority[CharsetPriority["META"] = 1] = "META";
    CharsetPriority[CharsetPriority["DEFAULT"] = 0] = "DEFAULT";
})(CharsetPriority || (CharsetPriority = {}));
class Charset {
    constructor() {
        this.charset = DEFAULT_CHARSET;
        this.priority = CharsetPriority.DEFAULT;
    }
    set(charset, priority) {
        if (charset && this.charset !== charset && this.priority <= priority) {
            this.charset = charset;
            this.priority = priority;
            return true;
        }
        return false;
    }
    get() {
        return this.charset;
    }
    isFromBOM() {
        return this.priority === CharsetPriority.BOM;
    }
    fromBOM(resBuf) {
        for (let i = 0; i < CHARSET_BOM_LIST.length; i++) {
            if ((0, buffer_1.startsWith)(resBuf, CHARSET_BOM_LIST[i].bom))
                return this.set(CHARSET_BOM_LIST[i].charset, CharsetPriority.BOM);
        }
        return false;
    }
    fromContentType(contentTypeHeader) {
        if (this.priority <= CharsetPriority.CONTENT_TYPE) {
            const charsetMatch = contentTypeHeader && contentTypeHeader.match(CHARSET_RE);
            const charset = charsetMatch && charsetMatch[1];
            if (!charset)
                return false;
            return this.set((0, labels_1.default)(charset), CharsetPriority.CONTENT_TYPE);
        }
        return false;
    }
    fromUrl(charsetFromUrl) {
        if (charsetFromUrl && this.priority <= CharsetPriority.URL)
            return this.set((0, labels_1.default)(charsetFromUrl), CharsetPriority.URL);
        return false;
    }
    // NOTE: Parsing charset from meta tags
    // www.whatwg.org/specs/web-apps/current-work/multipage/parsing.html#determining-the-character-encoding
    // Each <meta> descriptor should contain values of the "http-equiv", "content" and "charset" attributes.
    fromMeta(metas) {
        if (this.priority < CharsetPriority.META && metas.length) {
            let needPragma = true;
            let charsetStr = '';
            metas.forEach(attrs => {
                const shouldParseFromContentAttr = needPragma && attrs.content && attrs.httpEquiv &&
                    attrs.httpEquiv.toLowerCase() === builtin_header_names_1.default.contentType;
                if (shouldParseFromContentAttr) {
                    const charsetMatch = attrs.content.match(META_CHARSET_RE);
                    if (charsetMatch) {
                        needPragma = true;
                        charsetStr = charsetMatch[1];
                    }
                }
                if (attrs.charset) {
                    needPragma = false;
                    charsetStr = attrs.charset;
                }
            });
            return this.set((0, labels_1.default)(charsetStr), CharsetPriority.META);
        }
        return false;
    }
}
exports.default = Charset;module.exports = exports.default;