initial version - hackathon

imapParsing.ts

@@ -0,0 +1,175 @@
+export type ImapCommandParameters = string | string[] | Record<string, any>;
+
+export function parseImapCommand(commandString: string): {
+  tag: string;
+  command: string;
+  parameters: ImapCommandParameters[];
+} {
+  const parts: string[] = [];
+  let currentPart = "";
+  let inQuotes = false;
+  let parenDepth = 0;
+  let bracketDepth = 0;
+
+  for (let i = 0; i < commandString.length; i++) {
+    const char = commandString[i];
+
+    if (char === '"' && (i === 0 || commandString[i - 1] !== "\\")) {
+      inQuotes = !inQuotes;
+      currentPart += char;
+    } else if (char === "(" && !inQuotes) {
+      parenDepth++;
+      currentPart += char;
+    } else if (char === ")" && !inQuotes) {
+      parenDepth--;
+      currentPart += char;
+    } else if (char === "[" && !inQuotes) {
+      bracketDepth++;
+      currentPart += char;
+    } else if (char === "]" && !inQuotes) {
+      bracketDepth--;
+      currentPart += char;
+    } else if (
+      char === " " && !inQuotes && parenDepth === 0 && bracketDepth === 0
+    ) {
+      if (currentPart) {
+        parts.push(currentPart);
+        currentPart = "";
+      }
+    } else {
+      currentPart += char;
+    }
+  }
+
+  if (currentPart) {
+    parts.push(currentPart);
+  }
+
+  if (parts.length < 2) {
+    throw new Error("Invalid command");
+  }
+
+  const tag = parts[0];
+
+  let command = parts[1];
+  let paramStartIdx = 2;
+
+  if (command.toUpperCase() === "UID") {
+    command = `${command} ${parts[2]}`;
+    paramStartIdx = 3;
+  }
+
+  const parameters: ImapCommandParameters[] = [];
+
+  for (let i = paramStartIdx; i < parts.length; i++) {
+    let part = parts[i];
+
+    if (part.startsWith('"') && part.endsWith('"')) {
+      part = part.slice(1, -1);
+    }
+
+    if (part.includes('\\"')) {
+      parameters.push(part.split('\\"'));
+    } else if (part.startsWith("(") && part.endsWith(")")) {
+      parameters.push(parseDataItems(part));
+    } else {
+      parameters.push(part);
+    }
+  }
+
+  return {
+    tag,
+    command,
+    parameters,
+  };
+}
+
+export function parseDataItems(
+  dataItemsString: string,
+): ImapCommandParameters[] {
+  const inner = dataItemsString.slice(1, -1).trim();
+
+  if (!inner) return [];
+
+  const result: ImapCommandParameters[] = [];
+  let current = "";
+  let inQuotes = false;
+  let parenDepth = 0;
+  let bracketDepth = 0;
+  let fullSectionId = "";
+
+  for (let i = 0; i < inner.length; i++) {
+    const char = inner[i];
+
+    if (char === '"' && (i === 0 || inner[i - 1] !== "\\")) {
+      inQuotes = !inQuotes;
+      current += char;
+    } else if (char === "[" && !inQuotes) {
+      bracketDepth++;
+
+      if (
+        current.toUpperCase().startsWith("BODY.PEEK") ||
+        current.toUpperCase() === "BODY"
+      ) {
+        fullSectionId = current + char;
+        current += char;
+      } else {
+        current += char;
+      }
+    } else if (char === "(" && !inQuotes) {
+      parenDepth++;
+
+      if (bracketDepth > 0 && fullSectionId) {
+        fullSectionId = current;
+        current = "";
+      } else {
+        current += char;
+      }
+    } else if (char === ")" && !inQuotes) {
+      parenDepth--;
+
+      if (parenDepth === 0 && bracketDepth > 0 && fullSectionId) {
+        const fieldList = current.split(/\s+/).filter(Boolean);
+        current = fieldList;
+      } else {
+        current += char;
+      }
+    } else if (char === "]" && !inQuotes) {
+      bracketDepth--;
+
+      if (bracketDepth === 0 && fullSectionId) {
+        if (Array.isArray(current)) {
+          const sectionObj: Record<string, string[]> = {};
+          sectionObj[`${fullSectionId.trim()}]`] = current;
+          result.push(sectionObj);
+        } else {
+          result.push(`${fullSectionId}${current}]`);
+        }
+
+        fullSectionId = "";
+        current = "";
+      } else if (fullSectionId) {
+        current += char;
+      } else {
+        current += char;
+      }
+    } else if (
+      char === " " && !inQuotes && parenDepth === 0 && bracketDepth === 0
+    ) {
+      if (current) {
+        result.push(current);
+        current = "";
+      }
+    } else {
+      if (!Array.isArray(current)) {
+        current += char;
+      }
+    }
+  }
+
+  if (current && !Array.isArray(current)) {
+    result.push(current);
+  }
+
+  return result;
+}