Import of the watch repository from Pebble

src/fw/applib/fonts/codepoint.c

@@ -0,0 +1,147 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "codepoint.h"
+
+#include "util/size.h"
+
+#include <stddef.h>
+
+#define MAX_LATIN_CODEPOINT 0x02AF
+#define MIN_SOFTBANK_EMOJI_CODEPOINT 0xE000
+#define MAX_SOFTBANK_EMOJI_CODEPOINT 0xE537
+#define MIN_UNIFIED_EMOJI_CODEPOINT 0x1F300
+#define MAX_UNIFIED_EMOJI_CODEPOINT 0x1F6FF
+#define MIN_SYMBOLS_CODEPOINT 0x2000
+#define MAX_SYMBOLS_CODEPOINT 0x2BFF
+#define MIN_IDEOGRAPH_CODEPOINT 0x2e80
+#define MIN_SPECIAL_CODEPOINT 0xE0A0
+#define MAX_SPECIAL_CODEPOINT 0xE0A2
+#define MIN_SKIN_TONE_CODEPOINT 0x1F3FB
+#define MAX_SKIN_TONE_CODEPOINT 0x1F3FF
+
+// Note: Please keep these sorted
+static const Codepoint NONSTANDARD_EMOJI_CODEPOINTS[] = {
+    0x2192, // rightwards_arrow
+    0x25BA, // black_right_pointing_pointer
+    0x2605, // black_star
+    0x260E, // black_telephone
+    0x261D, // white_up_pointing_index
+    0x263A, // white_smiling_face
+    0x270A, // raised_fist
+    0x270B, // raised_hand
+    0x270C, // victory_hand
+    0x2764, // heavy_black_heart
+};
+
+// Note: Please keep these sorted
+static const Codepoint END_OF_WORD_CODEPOINTS[] = {
+  NULL_CODEPOINT, // 0x0
+  NEWLINE_CODEPOINT, // 0xa
+  SPACE_CODEPOINT, // 0x20
+  HYPHEN_CODEPOINT, // 0x2d
+  ZERO_WIDTH_SPACE_CODEPOINT // 0x200b
+};
+
+//  Note: Please keep these sorted
+static const Codepoint FORMATTING_CODEPOINTS[] = {
+  0x7F,   // delete
+  0x200C, // zero-width non-joiner
+  0x200D, // zero-width joiner
+  0x200E, // left to right
+  0x200F, // right to left
+  0x202A, // bidirectional - right to left
+  0x202C, // bidirectional - pop direction
+  0x202D, // left to right override
+  0xFE0E, // variation selector 1
+  0xFE0F, // variation selector 2
+  0xFEFF, // zero-width-no-break
+};
+
+// Note: Please keep these sorted
+static const Codepoint ZERO_WIDTH_CODEPOINTS[] = {
+  ZERO_WIDTH_SPACE_CODEPOINT,
+  WORD_JOINER_CODEPOINT,
+};
+
+static bool codepoint_in_list(const Codepoint codepoint, const Codepoint *codepoints, size_t size) {
+  for (size_t i = 0; i < size; ++i) {
+    if (codepoints[i] >= codepoint) {
+      return (codepoints[i] == codepoint);
+    }
+  }
+
+  return false;
+}
+
+bool codepoint_is_formatting_indicator(const Codepoint codepoint) {
+  return codepoint_in_list(codepoint, FORMATTING_CODEPOINTS, ARRAY_LENGTH(FORMATTING_CODEPOINTS));
+}
+
+bool codepoint_is_ideograph(const Codepoint codepoint) {
+  if (codepoint > MIN_IDEOGRAPH_CODEPOINT) {
+    // non ideographic characters. This is an approximation that is good enough until
+    // we start supporting some exotic scripts (e.g. tibetan)
+    return true;
+  } else {
+    return false;
+  }
+}
+
+// see http://www.unicode.org/reports/tr14/ for the whole enchilada
+bool codepoint_is_end_of_word(const Codepoint codepoint) {
+  return codepoint_in_list(codepoint, END_OF_WORD_CODEPOINTS, ARRAY_LENGTH(END_OF_WORD_CODEPOINTS));
+}
+
+// see http://unicode.org/reports/tr51/ section 2.2 "Diversity"
+bool codepoint_is_skin_tone_modifier(const Codepoint codepoint) {
+  return (codepoint >= MIN_SKIN_TONE_CODEPOINT && codepoint <= MAX_SKIN_TONE_CODEPOINT);
+}
+
+bool codepoint_should_skip(const Codepoint codepoint) {
+  return ((codepoint < 0x20 && codepoint != NEWLINE_CODEPOINT) ||
+          (codepoint_is_skin_tone_modifier(codepoint)));
+}
+
+bool codepoint_is_zero_width(const Codepoint codepoint) {
+  return codepoint_in_list(codepoint, ZERO_WIDTH_CODEPOINTS, ARRAY_LENGTH(ZERO_WIDTH_CODEPOINTS));
+}
+
+bool codepoint_is_latin(const Codepoint codepoint) {
+  return (codepoint <= MAX_LATIN_CODEPOINT ||
+         (codepoint >= MIN_SYMBOLS_CODEPOINT &&
+          codepoint <= MAX_SYMBOLS_CODEPOINT));
+}
+
+bool codepoint_is_emoji(const Codepoint codepoint) {
+  // search for the codepoint in the list of nonstandard emoji codepoints first.
+  const bool found = codepoint_in_list(codepoint,
+                                       NONSTANDARD_EMOJI_CODEPOINTS,
+                                       ARRAY_LENGTH(NONSTANDARD_EMOJI_CODEPOINTS));
+  if (found) {
+    return true;
+  } else {
+    return ((codepoint >= MIN_SOFTBANK_EMOJI_CODEPOINT &&
+             codepoint <= MAX_SOFTBANK_EMOJI_CODEPOINT) ||
+            (codepoint >= MIN_UNIFIED_EMOJI_CODEPOINT &&
+             codepoint <= MAX_UNIFIED_EMOJI_CODEPOINT));
+  }
+}
+
+bool codepoint_is_special(const Codepoint codepoint) {
+  return (codepoint >= MIN_SPECIAL_CODEPOINT &&
+          codepoint <= MAX_SPECIAL_CODEPOINT);
+}