26 lines
897 B
JavaScript
26 lines
897 B
JavaScript
// @flow
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import { escape } from 'lodash';
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import { Document, Block, Node } from 'slate';
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import slug from 'slug';
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// finds the index of this heading in the document compared to other headings
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// with the same slugified text
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function indexOfType(document, heading) {
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const slugified = escape(slug(heading.text));
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const headings = document.nodes.filter((node: Block) => {
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if (!node.text) return false;
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return node.type.match(/^heading/) && slugified === escape(slug(node.text));
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});
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return headings.indexOf(heading);
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}
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// calculates a unique slug for this heading based on it's text and position
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// in the document that is as stable as possible
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export default function headingToSlug(document: Document, node: Node) {
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const slugified = escape(slug(node.text));
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const index = indexOfType(document, node);
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if (index === 0) return slugified;
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return `${slugified}-${index}`;
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}
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