{"version":3,"file":"LayoutShiftManager.js","sources":["../../../../../src/metrics/web-vitals/lib/LayoutShiftManager.ts"],"sourcesContent":["/* eslint-disable jsdoc/require-jsdoc */\n/*\n * Copyright 2024 Google LLC\n *\n * Licensed under the Apache License, Version 2.0 (the \"License\");\n * you may not use this file except in compliance with the License.\n * You may obtain a copy of the License at\n *\n *     https://www.apache.org/licenses/LICENSE-2.0\n *\n * Unless required by applicable law or agreed to in writing, software\n * distributed under the License is distributed on an \"AS IS\" BASIS,\n * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\n * See the License for the specific language governing permissions and\n * limitations under the License.\n */\n\nexport class LayoutShiftManager {\n  // eslint-disable-next-line @typescript-eslint/explicit-member-accessibility\n  _onAfterProcessingUnexpectedShift?: (entry: LayoutShift) => void;\n\n  // oxlint-disable-next-line sdk/no-class-field-initializers\n  _sessionValue = 0;\n  // oxlint-disable-next-line sdk/no-class-field-initializers\n  _sessionEntries: LayoutShift[] = [];\n\n  // eslint-disable-next-line @typescript-eslint/explicit-member-accessibility\n  _processEntry(entry: LayoutShift) {\n    // Only count layout shifts without recent user input.\n    if (entry.hadRecentInput) return;\n\n    const firstSessionEntry = this._sessionEntries[0];\n    // This previously used `this._sessionEntries.at(-1)` but that is ES2022. We support ES2021 and earlier.\n    const lastSessionEntry = this._sessionEntries[this._sessionEntries.length - 1];\n\n    // If the entry occurred less than 1 second after the previous entry\n    // and less than 5 seconds after the first entry in the session,\n    // include the entry in the current session. Otherwise, start a new\n    // session.\n    if (\n      this._sessionValue &&\n      firstSessionEntry &&\n      lastSessionEntry &&\n      entry.startTime - lastSessionEntry.startTime < 1000 &&\n      entry.startTime - firstSessionEntry.startTime < 5000\n    ) {\n      this._sessionValue += entry.value;\n      this._sessionEntries.push(entry);\n    } else {\n      this._sessionValue = entry.value;\n      this._sessionEntries = [entry];\n    }\n\n    this._onAfterProcessingUnexpectedShift?.(entry);\n  }\n}\n"],"names":[],"mappings":"AAiBO,MAAM,kBAAA,CAAmB;AAAA,EAAzB,WAAA,GAAA;AAKL;AAAA,IAAA,IAAA,CAAA,aAAA,GAAgB,CAAA;AAEhB;AAAA,IAAA,IAAA,CAAA,eAAA,GAAiC,EAAC;AAAA,EAAA;AAAA;AAAA,EAGlC,cAAc,KAAA,EAAoB;AAEhC,IAAA,IAAI,MAAM,cAAA,EAAgB;AAE1B,IAAA,MAAM,iBAAA,GAAoB,IAAA,CAAK,eAAA,CAAgB,CAAC,CAAA;AAEhD,IAAA,MAAM,mBAAmB,IAAA,CAAK,eAAA,CAAgB,IAAA,CAAK,eAAA,CAAgB,SAAS,CAAC,CAAA;AAM7E,IAAA,IACE,IAAA,CAAK,aAAA,IACL,iBAAA,IACA,gBAAA,IACA,KAAA,CAAM,SAAA,GAAY,gBAAA,CAAiB,SAAA,GAAY,GAAA,IAC/C,KAAA,CAAM,SAAA,GAAY,iBAAA,CAAkB,YAAY,GAAA,EAChD;AACA,MAAA,IAAA,CAAK,iBAAiB,KAAA,CAAM,KAAA;AAC5B,MAAA,IAAA,CAAK,eAAA,CAAgB,KAAK,KAAK,CAAA;AAAA,IACjC,CAAA,MAAO;AACL,MAAA,IAAA,CAAK,gBAAgB,KAAA,CAAM,KAAA;AAC3B,MAAA,IAAA,CAAK,eAAA,GAAkB,CAAC,KAAK,CAAA;AAAA,IAC/B;AAEA,IAAA,IAAA,CAAK,oCAAoC,KAAK,CAAA;AAAA,EAChD;AACF;;;;"}