gistfile1.txt

enum AnswerStreamContext {
	BeforeCodeBlock,
	InCodeBlock,
	AfterCodeBlock,
}

interface AnswerStreamLine {
	line: string;
	context: AnswerStreamContext;
}

class AnswerSplitOnNewLineAccumulator {
	accumulator: string;
	runningAnswer: string;
	lines: AnswerStreamLine[];
	codeBlockStringFound: boolean;
	runningState: AnswerStreamContext;

	constructor() {
		this.accumulator = '';
		this.runningAnswer = '';
		this.lines = [];
		this.codeBlockStringFound = false;
		this.runningState = AnswerStreamContext.BeforeCodeBlock;
	}

	addDelta(delta: string | null | undefined) {
		if (delta === null || delta === undefined) {
			return;
		}
		// When we are adding delta, we need to check if after adding the delta
		// we get a new line, and if we do we split it on the new line and add it
		// to our queue of events to push
		this.accumulator = this.accumulator + delta;
		while (true) {
			const newLineIndex = this.accumulator.indexOf('\n');
			// If we found no new line, lets just break here
			if (newLineIndex === -1) {
				break;
			}
			const completeLine = this.accumulator.substring(0, newLineIndex);
			if (/^```/.test(completeLine)) {
				if (!this.codeBlockStringFound) {
					this.codeBlockStringFound = true;
					this.runningState = AnswerStreamContext.InCodeBlock;
				} else {
					this.runningState = AnswerStreamContext.AfterCodeBlock;
				}
			}
			this.lines.push({
				line: completeLine,
				context: this.runningState,
			});
			// we set the accumulator to the remaining line
			this.accumulator = this.accumulator.substring(newLineIndex + 1);
		}
	}

	getLine(): AnswerStreamLine | null {
		if (this.lines.length === 0) {
			return null;
		}
		// or give back the first element of the string
		const line = this.lines[0];
		// remove the first element from the array
		this.lines = this.lines.slice(1);
		return line;
	}

	getLineLength(): number {
		return this.lines.length;
	}
}