about summary refs log tree commit diff
path: root/src/alf/typography.tsx
blob: d00910bf87cee9d87851dc26cffb2f12bfdfee23 (plain) (blame)
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
import React from 'react'
import {TextProps as RNTextProps} from 'react-native'
import {StyleProp, TextStyle} from 'react-native'
import {UITextView} from 'react-native-uitextview'
import createEmojiRegex from 'emoji-regex'

import {isNative} from '#/platform/detection'
import {Alf, applyFonts, atoms, flatten} from '#/alf'

/**
 * Util to calculate lineHeight from a text size atom and a leading atom
 *
 * Example:
 *   `leading(atoms.text_md, atoms.leading_normal)` // => 24
 */
export function leading<
  Size extends {fontSize?: number},
  Leading extends {lineHeight?: number},
>(textSize: Size, leading: Leading) {
  const size = textSize?.fontSize || atoms.text_md.fontSize
  const lineHeight = leading?.lineHeight || atoms.leading_normal.lineHeight
  return Math.round(size * lineHeight)
}

/**
 * Ensures that `lineHeight` defaults to a relative value of `1`, or applies
 * other relative leading atoms.
 *
 * If the `lineHeight` value is > 2, we assume it's an absolute value and
 * returns it as-is.
 */
export function normalizeTextStyles(
  styles: StyleProp<TextStyle>,
  {
    fontScale,
    fontFamily,
  }: {
    fontScale: number
    fontFamily: Alf['fonts']['family']
  } & Pick<Alf, 'flags'>,
) {
  const s = flatten(styles)
  // should always be defined on these components
  s.fontSize = (s.fontSize || atoms.text_md.fontSize) * fontScale

  if (s?.lineHeight) {
    if (s.lineHeight !== 0 && s.lineHeight <= 2) {
      s.lineHeight = Math.round(s.fontSize * s.lineHeight)
    }
  } else if (!isNative) {
    s.lineHeight = s.fontSize
  }

  applyFonts(s, fontFamily)

  return s
}

export type StringChild = string | (string | null)[]
export type TextProps = Omit<RNTextProps, 'children'> & {
  /**
   * Lets the user select text, to use the native copy and paste functionality.
   */
  selectable?: boolean
  /**
   * Provides `data-*` attributes to the underlying `UITextView` component on
   * web only.
   */
  dataSet?: Record<string, string | number | undefined>
  /**
   * Appears as a small tooltip on web hover.
   */
  title?: string
} & (
    | {
        emoji?: true
        children: StringChild
      }
    | {
        emoji?: false
        children: RNTextProps['children']
      }
  )

const EMOJI = createEmojiRegex()

export function childHasEmoji(children: React.ReactNode) {
  return (Array.isArray(children) ? children : [children]).some(
    child => typeof child === 'string' && createEmojiRegex().test(child),
  )
}

export function childIsString(
  children: React.ReactNode,
): children is StringChild {
  return (
    typeof children === 'string' ||
    (Array.isArray(children) &&
      children.every(child => typeof child === 'string' || child === null))
  )
}

export function renderChildrenWithEmoji(
  children: StringChild,
  props: Omit<TextProps, 'children'> = {},
) {
  const normalized = Array.isArray(children) ? children : [children]

  return (
    <UITextView {...props}>
      {normalized.map(child => {
        if (typeof child !== 'string') return child

        const emojis = child.match(EMOJI)

        if (emojis === null) {
          return child
        }

        return child.split(EMOJI).map((stringPart, index) => (
          <UITextView key={index} {...props}>
            {stringPart}
            {emojis[index] ? (
              <UITextView
                {...props}
                style={[props?.style, {color: 'black', fontFamily: 'System'}]}>
                {emojis[index]}
              </UITextView>
            ) : null}
          </UITextView>
        ))
      })}
    </UITextView>
  )
}