File size: 3,513 Bytes
1e92f2d |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 |
import { css } from '@emotion/css'
import Prism from 'prismjs'
import 'prismjs/components/prism-markdown'
import React, { useCallback, useMemo } from 'react'
import { Descendant, NodeEntry, Range, Text, createEditor } from 'slate'
import { withHistory } from 'slate-history'
import { Editable, RenderLeafProps, Slate, withReact } from 'slate-react'
import { CustomEditor } from './custom-types.d'
const MarkdownPreviewExample = () => {
const renderLeaf = useCallback(
(props: RenderLeafProps) => <Leaf {...props} />,
[]
)
const editor = useMemo(
() => withHistory(withReact(createEditor())) as CustomEditor,
[]
)
const decorate = useCallback(([node, path]: NodeEntry) => {
const ranges: Range[] = []
if (!Text.isText(node)) {
return ranges
}
const getLength = (token: string | Prism.Token): number => {
if (typeof token === 'string') {
return token.length
} else if (typeof token.content === 'string') {
return token.content.length
} else {
return (token.content as Prism.Token[]).reduce(
(l, t) => l + getLength(t),
0
)
}
}
const tokens = Prism.tokenize(node.text, Prism.languages.markdown)
let start = 0
for (const token of tokens) {
const length = getLength(token)
const end = start + length
if (typeof token !== 'string') {
ranges.push({
[token.type]: true,
anchor: { path, offset: start },
focus: { path, offset: end },
})
}
start = end
}
return ranges
}, [])
return (
<Slate editor={editor} initialValue={initialValue}>
<Editable
decorate={decorate}
renderLeaf={renderLeaf}
placeholder="Write some markdown..."
/>
</Slate>
)
}
const Leaf = ({ attributes, children, leaf }: RenderLeafProps) => {
return (
<span
{...attributes}
className={css`
font-weight: ${leaf.bold && 'bold'};
font-style: ${leaf.italic && 'italic'};
text-decoration: ${leaf.underlined && 'underline'};
${leaf.title &&
css`
display: inline-block;
font-weight: bold;
font-size: 20px;
margin: 20px 0 10px 0;
`}
${leaf.list &&
css`
padding-left: 10px;
font-size: 20px;
line-height: 10px;
`}
${leaf.hr &&
css`
display: block;
text-align: center;
border-bottom: 2px solid #ddd;
`}
${leaf.blockquote &&
css`
display: inline-block;
border-left: 2px solid #ddd;
padding-left: 10px;
color: #aaa;
font-style: italic;
`}
${leaf.code &&
css`
font-family: monospace;
background-color: #eee;
padding: 3px;
`}
`}
>
{children}
</span>
)
}
const initialValue: Descendant[] = [
{
type: 'paragraph',
children: [
{
text: 'Slate is flexible enough to add **decorations** that can format text based on its content. For example, this editor has **Markdown** preview decorations on it, to make it _dead_ simple to make an editor with built-in Markdown previewing.',
},
],
},
{
type: 'paragraph',
children: [{ text: '## Try it out!' }],
},
{
type: 'paragraph',
children: [{ text: 'Try it out for yourself!' }],
},
]
export default MarkdownPreviewExample
|