| | | 1 | | // ----------------------------------------------------------------------- |
| | | 2 | | // <copyright file="FixedNumberOfWordsTextTruncator.cs" company="Stéphane ANDRE"> |
| | | 3 | | // Copyright (c) Stéphane ANDRE. All rights reserved. |
| | | 4 | | // </copyright> |
| | | 5 | | // ----------------------------------------------------------------------- |
| | | 6 | | |
| | | 7 | | using System.Globalization; |
| | | 8 | | |
| | | 9 | | namespace MyNet.Text.Truncation; |
| | | 10 | | |
| | | 11 | | /// <summary> |
| | | 12 | | /// Truncates a string to a fixed number of words, either from the left or the right, depending on the specified truncat |
| | | 13 | | /// </summary> |
| | | 14 | | /// <param name="options">The options for truncation, including the number of words and the truncation direction.</param |
| | | 15 | | public sealed class FixedNumberOfWordsTextTruncator(TextTruncationOptions options) |
| | 90 | 16 | | : TextTruncatorBase(options) |
| | | 17 | | { |
| | | 18 | | /// <summary> |
| | | 19 | | /// Counts the number of words in the input string by iterating through each character and determining when a new wo |
| | | 20 | | /// </summary> |
| | | 21 | | /// <param name="value">The input string to count words in.</param> |
| | | 22 | | /// <returns>The number of words in the input string.</returns> |
| | | 23 | | private static int CountWords(string value) |
| | | 24 | | { |
| | 78 | 25 | | var count = 0; |
| | 78 | 26 | | var insideWord = false; |
| | | 27 | | |
| | 5820 | 28 | | foreach (var c in value) |
| | | 29 | | { |
| | 2832 | 30 | | if (char.IsWhiteSpace(c)) |
| | | 31 | | { |
| | 408 | 32 | | insideWord = false; |
| | 408 | 33 | | continue; |
| | | 34 | | } |
| | | 35 | | |
| | 2424 | 36 | | if (!insideWord) |
| | | 37 | | { |
| | 474 | 38 | | insideWord = true; |
| | 474 | 39 | | count++; |
| | | 40 | | } |
| | | 41 | | } |
| | | 42 | | |
| | 78 | 43 | | return count; |
| | | 44 | | } |
| | | 45 | | |
| | | 46 | | /// <inheritdoc/> |
| | | 47 | | protected override string ApplyCore(string input, CultureInfo culture) |
| | | 48 | | { |
| | 90 | 49 | | if (string.IsNullOrWhiteSpace(input)) |
| | 12 | 50 | | return input; |
| | | 51 | | |
| | 78 | 52 | | var wordCount = CountWords(input); |
| | | 53 | | |
| | 78 | 54 | | return wordCount <= Options.Length |
| | 78 | 55 | | ? input |
| | 78 | 56 | | : Options.Direction switch |
| | 78 | 57 | | { |
| | 24 | 58 | | TruncateFrom.Left => TruncateFromLeft(input), |
| | 18 | 59 | | _ => TruncateFromRight(input) |
| | 78 | 60 | | }; |
| | | 61 | | } |
| | | 62 | | |
| | | 63 | | /// <summary> |
| | | 64 | | /// Truncates the input string from the right, keeping only the specified number of words from the left. |
| | | 65 | | /// </summary> |
| | | 66 | | /// <param name="input">The input string to truncate.</param> |
| | | 67 | | /// <returns>The truncated string.</returns> |
| | | 68 | | private string TruncateFromRight(string input) |
| | | 69 | | { |
| | 18 | 70 | | var words = 0; |
| | 18 | 71 | | var insideWord = false; |
| | | 72 | | |
| | 906 | 73 | | for (var i = 0; i < input.Length; i++) |
| | | 74 | | { |
| | 453 | 75 | | var isWhiteSpace = char.IsWhiteSpace(input[i]); |
| | | 76 | | |
| | | 77 | | switch (isWhiteSpace) |
| | | 78 | | { |
| | 381 | 79 | | case false when !insideWord: |
| | 90 | 80 | | insideWord = true; |
| | 90 | 81 | | words++; |
| | 90 | 82 | | break; |
| | | 83 | | case true: |
| | 72 | 84 | | insideWord = false; |
| | | 85 | | break; |
| | | 86 | | } |
| | | 87 | | |
| | 453 | 88 | | if (words > Options.Length) |
| | | 89 | | { |
| | 18 | 90 | | return TruncateRight(input, i - 1); |
| | | 91 | | } |
| | | 92 | | } |
| | | 93 | | |
| | 0 | 94 | | return input; |
| | | 95 | | } |
| | | 96 | | |
| | | 97 | | /// <summary> |
| | | 98 | | /// Truncates the input string from the left, keeping only the specified number of words from the right. |
| | | 99 | | /// </summary> |
| | | 100 | | /// <param name="input">The input string to truncate.</param> |
| | | 101 | | /// <returns>The truncated string.</returns> |
| | | 102 | | private string TruncateFromLeft(string input) |
| | | 103 | | { |
| | 24 | 104 | | var words = 0; |
| | 24 | 105 | | var insideWord = false; |
| | | 106 | | |
| | 1344 | 107 | | for (var i = input.Length - 1; i >= 0; i--) |
| | | 108 | | { |
| | 672 | 109 | | var isWhiteSpace = char.IsWhiteSpace(input[i]); |
| | | 110 | | |
| | | 111 | | switch (isWhiteSpace) |
| | | 112 | | { |
| | 564 | 113 | | case false when !insideWord: |
| | 120 | 114 | | insideWord = true; |
| | 120 | 115 | | words++; |
| | 120 | 116 | | break; |
| | | 117 | | case true: |
| | 108 | 118 | | insideWord = false; |
| | | 119 | | break; |
| | | 120 | | } |
| | | 121 | | |
| | 672 | 122 | | if (words > Options.Length) |
| | | 123 | | { |
| | 24 | 124 | | var startIndex = i + 1; |
| | | 125 | | |
| | 48 | 126 | | while (startIndex < input.Length && char.IsWhiteSpace(input[startIndex])) |
| | | 127 | | { |
| | 24 | 128 | | startIndex++; |
| | | 129 | | } |
| | | 130 | | |
| | 24 | 131 | | return string.Concat(Options.TruncationString, input[startIndex..].TrimEnd()); |
| | | 132 | | } |
| | | 133 | | } |
| | | 134 | | |
| | 0 | 135 | | return input; |
| | | 136 | | } |
| | | 137 | | } |
| | | 138 | | |