47 lines
1.1 KiB
JavaScript
47 lines
1.1 KiB
JavaScript
function pageNumber (number, size, recordCount) {
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let numberOfPages = Math.ceil(recordCount / size);
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number = parseInt(number) || 1;
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// Ensure page number is in range
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number = number < 1 ? 1 : number;
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number = number > numberOfPages ? numberOfPages : number;
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return number;
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}
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function buildIds (order, number, size, recordCount) {
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let offset = size * (number - 1);
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let start;
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let mapFunction;
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if (order === 'asc') {
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start = 1 + offset;
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mapFunction = (_, i) => start + i;
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} else {
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start = recordCount - offset;
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mapFunction = (_, i) => start - i;
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}
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// Ensure size is in range
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let end = offset + size;
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if (end > recordCount) {
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let diff = end - recordCount;
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size = size - diff;
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}
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return Array.from({ length: size }, mapFunction);
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}
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module.exports = function paged (recordCount, options = {}) {
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let { order, page } = options;
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order = order || 'desc';
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page = page || {};
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let size = parseInt(page.size) || 25;
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let number = pageNumber(page.number, size, recordCount);
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return buildIds(order, number, size, recordCount);
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};
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