"use strict";
Object.defineProperty(exports, "__esModule", { value: !0 });
var __defProp = Object.defineProperty, __defNormalProp = (obj, key, value) => key in obj ? __defProp(obj, key, { enumerable: !0, configurable: !0, writable: !0, value }) : obj[key] = value, __publicField = (obj, key, value) => __defNormalProp(obj, typeof key != "symbol" ? key + "" : key, value);
class ParseError extends Error {
  constructor(message, options) {
    super(message), __publicField(this, "type"), __publicField(this, "field"), __publicField(this, "value"), __publicField(this, "line"), this.name = "ParseError", this.type = options.type, this.field = options.field, this.value = options.value, this.line = options.line;
  }
}
function noop(_arg) {
}
function createParser(callbacks) {
  const { onEvent = noop, onError = noop, onRetry = noop, onComment } = callbacks;
  let incompleteLine = "", isFirstChunk = !0, id, data = "", eventType = "";
  function feed(newChunk) {
    const chunk = isFirstChunk ? newChunk.replace(/^\xEF\xBB\xBF/, "") : newChunk, [complete, incomplete] = splitLines(`${incompleteLine}${chunk}`);
    for (const line of complete)
      parseLine(line);
    incompleteLine = incomplete, isFirstChunk = !1;
  }
  function parseLine(line) {
    if (line === "") {
      dispatchEvent();
      return;
    }
    if (line.startsWith(":")) {
      onComment && onComment(line.slice(line.startsWith(": ") ? 2 : 1));
      return;
    }
    const fieldSeparatorIndex = line.indexOf(":");
    if (fieldSeparatorIndex !== -1) {
      const field = line.slice(0, fieldSeparatorIndex), offset = line[fieldSeparatorIndex + 1] === " " ? 2 : 1, value = line.slice(fieldSeparatorIndex + offset);
      processField(field, value, line);
      return;
    }
    processField(line, "", line);
  }
  function processField(field, value, line) {
    switch (field) {
      case "event":
        eventType = value;
        break;
      case "data":
        data = `${data}${value}
`;
        break;
      case "id":
        id = value.includes("\0") ? void 0 : value;
        break;
      case "retry":
        /^\d+$/.test(value) ? onRetry(parseInt(value, 10)) : onError(
          new ParseError(`Invalid \`retry\` value: "${value}"`, {
            type: "invalid-retry",
            value,
            line
          })
        );
        break;
      default:
        onError(
          new ParseError(
            `Unknown field "${field.length > 20 ? `${field.slice(0, 20)}\u2026` : field}"`,
            { type: "unknown-field", field, value, line }
          )
        );
        break;
    }
  }
  function dispatchEvent() {
    data.length > 0 && onEvent({
      id,
      event: eventType || void 0,
      // If the data buffer's last character is a U+000A LINE FEED (LF) character,
      // then remove the last character from the data buffer.
      data: data.endsWith(`
`) ? data.slice(0, -1) : data
    }), id = void 0, data = "", eventType = "";
  }
  function reset(options = {}) {
    incompleteLine && options.consume && parseLine(incompleteLine), id = void 0, data = "", eventType = "", incompleteLine = "";
  }
  return { feed, reset };
}
function splitLines(chunk) {
  const lines = [];
  let incompleteLine = "";
  const totalLength = chunk.length;
  for (let i = 0; i < totalLength; i++) {
    const char = chunk[i];
    char === "\r" && chunk[i + 1] === `
` ? (lines.push(incompleteLine), incompleteLine = "", i++) : char === "\r" || char === `
` ? (lines.push(incompleteLine), incompleteLine = "") : incompleteLine += char;
  }
  return [lines, incompleteLine];
}
exports.ParseError = ParseError;
exports.createParser = createParser;
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