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"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
var finished_1 = require("../../encoding/finished");
var terminology_1 = require("../../encoding/terminology");
var utilities_1 = require("../../encoding/utilities");
/**
* @constructor
* @implements {Encoder}
* @param {{fatal: boolean}} options
*/
var UTF8Encoder = /** @class */ (function () {
function UTF8Encoder(options) {
this.fatal = options.fatal;
}
/**
* @param {Stream} stream Input stream.
* @param {number} code_point Next code point read from the stream.
* @return {(number|!Array.<number>)} Byte(s) to emit.
*/
UTF8Encoder.prototype.handler = function (stream, code_point) {
// 1. If code point is end-of-stream, return finished.
if (code_point === terminology_1.end_of_stream)
return finished_1.finished;
// 2. If code point is an ASCII code point, return a byte whose
// value is code point.
if (terminology_1.isASCIICodePoint(code_point))
return code_point;
// 3. Set count and offset based on the range code point is in:
var count, offset;
// U+0080 to U+07FF, inclusive:
if (utilities_1.inRange(code_point, 0x0080, 0x07FF)) {
// 1 and 0xC0
count = 1;
offset = 0xC0;
}
// U+0800 to U+FFFF, inclusive:
else if (utilities_1.inRange(code_point, 0x0800, 0xFFFF)) {
// 2 and 0xE0
count = 2;
offset = 0xE0;
}
// U+10000 to U+10FFFF, inclusive:
else if (utilities_1.inRange(code_point, 0x10000, 0x10FFFF)) {
// 3 and 0xF0
count = 3;
offset = 0xF0;
}
// 4. Let bytes be a byte sequence whose first byte is (code
// point >> (6 × count)) + offset.
var bytes = [(code_point >> (6 * count)) + offset];
// 5. Run these substeps while count is greater than 0:
while (count > 0) {
// 1. Set temp to code point >> (6 × (count − 1)).
var temp = code_point >> (6 * (count - 1));
// 2. Append to bytes 0x80 | (temp & 0x3F).
bytes.push(0x80 | (temp & 0x3F));
// 3. Decrease count by one.
count -= 1;
}
// 6. Return bytes bytes, in order.
return bytes;
};
return UTF8Encoder;
}());
exports.UTF8Encoder = UTF8Encoder;
//# sourceMappingURL=UTF8Encoder.js.map