return lastMatch?.[1]?.trim() || null;

}

function extractCaptures(text: string, pattern: RegExp) {

const flags = pattern.flags.includes("g") ? pattern.flags : `${pattern.flags}g`;

const globalPattern = new RegExp(pattern.source, flags);

return Array.from(text.matchAll(globalPattern), (match) => match[1]?.trim()).filter(Boolean);

}

function extractLastMatchingUserText(texts: string[], pattern: RegExp) {

for (let index = texts.length - 1; index >= 0; index -= 1) {

const text = texts[index] ?? "";

);

}

function extractBlockStreamingMarkerDirectives(text: string) {

const firstLabeledMarker = extractLabeledMarkerDirective(text, "first exact marker");

const secondLabeledMarker = extractLabeledMarkerDirective(text, "second exact marker");

if (firstLabeledMarker && secondLabeledMarker) {

return {

first: firstLabeledMarker,

second: secondLabeledMarker,

};

}

const markers = extractCaptures(text, /exact marker\b[^:\n]{0,120}:\s*`([^`]+)`/i);

if (markers.length < 2) {

return null;

}

const [first, second] = markers.slice(-2);

return first && second

? {

first,

second,

}

: null;

}

function extractQuotedToolArg(text: string, name: string) {

const escapedName = escapeRegExp(name);

return extractLastCapture(text, new RegExp(`\\b${escapedName}\\s*=\\s*"([^"]+)"`, "i"));

extractExactReplyDirective(prompt) ?? extractExactReplyDirective(allInputText);

const exactMarkerDirective =

extractExactMarkerDirective(prompt) ?? extractExactMarkerDirective(allInputText);

const blockStreamingPrompt =

extractLastMatchingUserText(extractAllUserTexts(input), QA_BLOCK_STREAMING_PROMPT_RE) ||

prompt ||

allInputText;

const blockStreamingMarkers =

extractBlockStreamingMarkerDirectives(blockStreamingPrompt) ??

extractBlockStreamingMarkerDirectives(allInputText);

const latestImageUserTurn = extractLatestImageUserTurn(input);

const firstExactMarkerDirective = extractLabeledMarkerDirective(

allInputText,

"first exact marker",

);

const secondExactMarkerDirective = extractLabeledMarkerDirective(

allInputText,

"second exact marker",

);

const isGroupChat = allInputText.includes('"is_group_chat": true');

const isBaselineUnmentionedChannelChatter = /\bno bot ping here\b/i.test(prompt);

const hasReasoningOnlyRetryInstruction = allInputText.includes(QA_REASONING_ONLY_RETRY_NEEDLE);

}

return buildAssistantEvents(toolProgressReplyDirective);

}

if (

QA_BLOCK_STREAMING_PROMPT_RE.test(allInputText) &&

firstExactMarkerDirective &&

secondExactMarkerDirective

) {

if (QA_BLOCK_STREAMING_PROMPT_RE.test(allInputText) && blockStreamingMarkers) {

return buildAssistantEvents([

{

id: "msg_mock_block_1",

phase: "final_answer",

streamDeltas: splitMockStreamingText(firstExactMarkerDirective),

text: firstExactMarkerDirective,

streamDeltas: splitMockStreamingText(blockStreamingMarkers.first),

text: blockStreamingMarkers.first,

},

{

id: "msg_mock_block_2",

phase: "final_answer",

streamDeltas: splitMockStreamingText(secondExactMarkerDirective),

text: secondExactMarkerDirective,

streamDeltas: splitMockStreamingText(blockStreamingMarkers.second),

text: blockStreamingMarkers.second,

},

]);

}