21 lines
727 B
JavaScript
21 lines
727 B
JavaScript
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'use strict';
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/**
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* Determine what entries should be displayed on the screen, based on the
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* currently selected index and the maximum visible. Used in list-based
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* prompts like `select` and `multiselect`.
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*
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* @param {number} cursor the currently selected entry
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* @param {number} total the total entries available to display
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* @param {number} [maxVisible] the number of entries that can be displayed
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*/
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module.exports = (cursor, total, maxVisible) => {
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maxVisible = maxVisible || total;
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let startIndex = Math.min(total - maxVisible, cursor - Math.floor(maxVisible / 2));
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if (startIndex < 0) startIndex = 0;
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let endIndex = Math.min(startIndex + maxVisible, total);
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return {
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startIndex,
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endIndex
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};
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};
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