1 /*
<lambda>null2  * Copyright 2022 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package androidx.compose.foundation.text
18 
19 import androidx.compose.runtime.Composable
20 import androidx.compose.ui.layout.Layout
21 import androidx.compose.ui.text.AnnotatedString
22 import androidx.compose.ui.text.Placeholder
23 import androidx.compose.ui.util.fastForEach
24 import androidx.compose.ui.util.fastMap
25 
26 internal typealias PlaceholderRange = AnnotatedString.Range<Placeholder>
27 
28 internal typealias InlineContentRange = AnnotatedString.Range<@Composable (String) -> Unit>
29 
30 /**
31  * Attempts to match AnnotatedString placeholders with passed [InlineTextContent]
32  *
33  * Matches will produce a entry in both returned lists.
34  *
35  * Non-matches will be ignored silently.
36  */
37 internal fun AnnotatedString.resolveInlineContent(
38     inlineContent: Map<String, InlineTextContent>?
39 ): Pair<List<PlaceholderRange>, List<InlineContentRange>> {
40     if (inlineContent.isNullOrEmpty()) {
41         return EmptyInlineContent
42     }
43     val inlineContentAnnotations = getStringAnnotations(INLINE_CONTENT_TAG, 0, text.length)
44 
45     val placeholders = mutableListOf<AnnotatedString.Range<Placeholder>>()
46     val inlineComposables = mutableListOf<AnnotatedString.Range<@Composable (String) -> Unit>>()
47     inlineContentAnnotations.fastForEach { annotation ->
48         inlineContent[annotation.item]?.let { inlineTextContent ->
49             placeholders.add(
50                 AnnotatedString.Range(
51                     inlineTextContent.placeholder,
52                     annotation.start,
53                     annotation.end
54                 )
55             )
56             inlineComposables.add(
57                 AnnotatedString.Range(inlineTextContent.children, annotation.start, annotation.end)
58             )
59         }
60     }
61     return Pair(placeholders, inlineComposables)
62 }
63 
hasInlineContentnull64 internal fun AnnotatedString.hasInlineContent(): Boolean =
65     hasStringAnnotations(INLINE_CONTENT_TAG, 0, text.length)
66 
67 @Composable
68 internal fun InlineChildren(text: AnnotatedString, inlineContents: List<InlineContentRange>) {
69     inlineContents.fastForEach { (content, start, end) ->
70         Layout(content = { content(text.subSequence(start, end).text) }) { children, constrains ->
71             val placeables = children.fastMap { it.measure(constrains) }
72             layout(width = constrains.maxWidth, height = constrains.maxHeight) {
73                 placeables.fastForEach { it.placeRelative(0, 0) }
74             }
75         }
76     }
77 }
78 
79 private val EmptyInlineContent: Pair<List<PlaceholderRange>, List<InlineContentRange>> =
80     Pair(emptyList(), emptyList())
81