feat: 开源蟹蟹输入RTOS适配改版并采用MIT商用许可

com.sydxky.rtos.inputmethod/third_party/crabKeyboard/lookupDictV5.original.js

@@ -0,0 +1,106 @@
+import File from '@system.file';
+
+const _this = {
+  lookupDict: lookupDict,
+};
+
+const SEP_ENTRY = "\u001e";
+const SEP_OFFLEN = "\u001f";
+
+function from94(str) {
+  const CHAR_START = 33;
+  const BASE = 94;
+  let result = 0;
+  for (let i = 0; i < str.length; i++) {
+    result = result * BASE + (str.charCodeAt(i) - CHAR_START);
+  }
+  return result;
+}
+
+/**
+ * @param baseDir 字典目录
+ * @param key 查找的字符串
+ * @param then 回调 (match, key, result)
+ */
+function lookupDict(baseDir, key, then) {
+  const searchKey = key.toLowerCase();
+  let depth = 0;
+
+  // 记录最长前缀匹配
+  let bestMatch = { key: "", off: -1, len: -1, depth: -1 };
+
+  function step(readOff, readLen) {
+    File.readText({
+      uri: baseDir + "/key" + depth + ".dat",
+      position: readOff,
+      length: readLen,
+
+      fail: (data, code) => {
+        if (bestMatch.off !== -1) {
+          readValue(bestMatch.off, bestMatch.len, bestMatch.depth, function (v) {
+            then(bestMatch.key, v);
+          });
+        } else {
+          then("", null);
+        }
+      },
+
+      success: d => {
+        const text = d.text;
+        const entries = text.split(SEP_ENTRY);
+        const targetChar = searchKey[depth];
+
+        for (let i = 0; i < entries.length; i++) {
+          const entry = entries[i];
+          if (!entry) continue;
+
+          const char = entry[0];
+          const parts = entry.substring(1).split(SEP_OFFLEN);
+          const vOff = from94(parts[0]);
+          const vLen = from94(parts[1]);
+
+          // 处理当前节点的叶子数据 (前缀匹配)
+          if (char === "_") {
+            bestMatch.key = searchKey.substring(0, depth);
+            bestMatch.off = vOff;
+            bestMatch.len = vLen;
+            bestMatch.depth = depth;
+          }
+
+          // 处理通往下一层的路径
+          if (char === targetChar) {
+            if (depth === searchKey.length) {
+              // 精确匹配结束
+              break;
+            }
+            depth++;
+            return setTimeout(() => step(vOff, vLen), 0);
+          }
+        }
+
+        // 没有找到下一层，返回最长匹配
+        if (bestMatch.off !== -1) {
+          readValue(bestMatch.off, bestMatch.len, bestMatch.depth, function (v) {
+            then(bestMatch.key, v);
+          });
+        } else {
+          then("", null);
+        }
+      }
+    });
+  }
+
+  function readValue(vPos, vLen, vDepth, callback) {
+    File.readText({
+      uri: baseDir + "/value" + vDepth + ".dat",
+      position: vPos,
+      length: vLen,
+      fail: function () { callback(null); },
+      success: function (data) { callback(data.text); }
+    });
+  }
+
+  step(0, 1024);
+}
+
+export default _this;