Data editor base: EntityEditorWindow (searchable list, form over JSON entities, texts in every language of the mod, other fields as JSON), EntityDocument, LocaleFileService, PropertiesText; mod tests

src/Services/PropertiesText.cs

@@ -0,0 +1,78 @@
+using System;
+using System.Collections.Generic;
+
+namespace Cthangover.Tools.Services
+{
+    /// <summary>
+    /// Reading and changing one key of a <c>.properties</c> text the way
+    /// <c>LocaleLoader</c> reads it: <c>key = value</c> per line, <c>#</c> comments,
+    /// no escapes and no multi-line values (a line break in a value becomes a
+    /// space). Everything else in the text — comments, order, other keys, the
+    /// line endings — stays byte for byte, so an editor save shows up in a diff
+    /// as the one changed line.
+    /// </summary>
+    public static class PropertiesText
+    {
+        /// <summary>The value of <paramref name="key"/>, or null when the text does not declare it (the last line wins, as in the loader).</summary>
+        public static string Get(string text, string key)
+        {
+            string found = null;
+            foreach (var line in Lines(text))
+            {
+                if (KeyOf(line) == key)
+                    found = line.Substring(line.IndexOf('=') + 1).Trim();
+            }
+            return found;
+        }
+
+        /// <summary>All keys declared in the text.</summary>
+        public static HashSet<string> Keys(string text)
+        {
+            var keys = new HashSet<string>(StringComparer.Ordinal);
+            foreach (var line in Lines(text))
+            {
+                var key = KeyOf(line);
+                if (key != null)
+                    keys.Add(key);
+            }
+            return keys;
+        }
+
+        /// <summary>
+        /// The text with <paramref name="key"/> set to <paramref name="value"/>: every
+        /// line of the key is rewritten in place, or a <c>key = value</c> line is
+        /// appended (after a line break the text may lack). Line endings follow the text.
+        /// </summary>
+        public static string Set(string text, string key, string value)
+        {
+            text ??= string.Empty;
+            value = (value ?? string.Empty).Replace("\r", " ").Replace("\n", " ").Trim();
+            var newline = text.Contains("\r\n") ? "\r\n" : "\n";
+            var lines = text.Split('\n');
+            var replaced = false;
+            for (var i = 0; i < lines.Length; i++)
+            {
+                var hasCr = lines[i].EndsWith("\r");
+                if (KeyOf(hasCr ? lines[i][..^1] : lines[i]) != key)
+                    continue;
+                lines[i] = $"{key} = {value}" + (hasCr ? "\r" : string.Empty);
+                replaced = true;
+            }
+            if (replaced)
+                return string.Join("\n", lines);
+            var head = text.Length == 0 || text.EndsWith("\n") ? text : text + newline;
+            return head + $"{key} = {value}" + newline;
+        }
+
+        private static IEnumerable<string> Lines(string text) => (text ?? string.Empty).Replace("\r\n", "\n").Split('\n');
+
+        private static string KeyOf(string rawLine)
+        {
+            var line = rawLine.Trim();
+            if (line.Length == 0 || line[0] == '#')
+                return null;
+            var eq = line.IndexOf('=');
+            return eq <= 0 ? null : line.Substring(0, eq).Trim();
+        }
+    }
+}