Refactor code

src/index.ts

@@ -1,3 +1,2 @@
-import {parse} from "./generated/grammar/task";
+import { loadTasks } from "./loader";
 
-console.log(parse("- [t]"));

src/loader/index.ts

@@ -0,0 +1,104 @@
+import fs from "fs";
+import dayjs from "dayjs";
+import { createInterface } from "readline";
+import { parse } from "../generated/grammar/task";
+import { Task as DefaultTask } from "../model";
+import { ParseResult } from "../types/grammar/task";
+import { Task, TaskPriority } from "../types/task";
+
+/**
+ * Returns all tasks from specified directory and filters them with optional query.
+ */
+export async function loadTasks(directories: string[], query?: string): Promise<Task[]> {
+  const ctx = {
+    now: dayjs(),
+    LOWEST: TaskPriority.LOWEST,
+    LOW: TaskPriority.LOW,
+    NORMAL: TaskPriority.NORMAL,
+    MEDIUM: TaskPriority.MEDIUM,
+    HIGH: TaskPriority.HIGH,
+    HIGHEST: TaskPriority.HIGHEST
+  };
+
+  const filter = query && createFilter(query, ctx);
+  const tasks = await Promise.all(directories.map(readTasksFromDirectory));
+  
+  return tasks.flat().filter(t => filter ? filter(t) : true);
+}
+
+/**
+ * Creates a filter function for tasks using a query string and context object.
+ * All context' properties will be passed as variables to the query string.
+ */
+function createFilter(query: string, context: Record<string, unknown>): (task: Task) => boolean {
+  const filter = new Function('$', ...Object.keys(context), `return ${query};`);
+  return (task: Task) => filter(task, ...Object.values(context));
+}
+
+/**
+ * Read all files in specific directory and returns all tasks from those files.
+ */
+async function readTasksFromDirectory(directory: string): Promise<Task[]> {
+  return walk(directory, readTasksFromFile);
+}
+
+/**
+ * Walks through a specific directory recursively and invokes visitor on each file.
+ * Returns a flat list of items returned by visitors.
+ */
+async function walk<T>(directory: string, visitor: (path: string) => Promise<T[]>): Promise<T[]> {  
+  const list = [];
+
+  for(const file of fs.readdirSync(directory)) {
+    const path = `${directory}/${file}`;  
+
+    if (fs.statSync(path).isDirectory()) {
+      const items = await walk(path, visitor);
+      list.push(...items);
+    } else {
+      const items = await visitor(path);
+      list.push(...items);
+    }
+  }
+
+  return list;
+}
+
+/**
+ * Reads all tasks from file path.
+ */
+async function readTasksFromFile(path: string): Promise<Task[]> {
+  const fileStream = fs.createReadStream(path);
+
+  const lines = createInterface({
+    input: fileStream,
+    crlfDelay: Infinity
+  });
+
+  const list: Task[] = [];
+  
+  for await (const line of lines) {
+    const task = parseTask(line);
+    
+    if(task) {
+      list.push(task);
+    }
+  }
+
+  return list;
+}
+
+/**
+ * Converts line to task model.
+ * If the line does not represent task, returns undefined.
+ */
+function parseTask(line: string): Task|undefined {
+  const item = parse(line) as ParseResult;
+
+  if (item.type === 'task') {
+    return new DefaultTask(item.data);
+  }
+
+  return undefined;
+}
+

src/model/index.ts

@@ -0,0 +1 @@
+export {LazyTask as Task} from "./task";

src/notepad/index.ts

@@ -1,47 +0,0 @@
-import fs from "fs";
-import readline from "readline";
-import { Task } from "../types/task";
-import { parse } from "../parser";
-
-export async function readTasksFromDirectory(directory: string): Promise<Task[]> {
-  return walk(directory, readTasksFromFile);
-}
-
-export async function walk<T>(directory: string, visitor: (path: string) => Promise<T[]>): Promise<T[]> {  
-  const list = [];
-
-  for(const file of fs.readdirSync(directory)) {
-    const path = `${directory}/${file}`;  
-
-    if (fs.statSync(path).isDirectory()) {
-      const items = await walk(path, visitor);
-      list.push(...items);
-    } else {
-      const items = await visitor(path);
-      list.push(...items);
-    }
-  }
-
-  return list;
-}
-
-export async function readTasksFromFile(path: string): Promise<Task[]> {
-  const fileStream = fs.createReadStream(path);
-
-  const rl = readline.createInterface({
-    input: fileStream,
-    crlfDelay: Infinity
-  });
-
-  const list: Task[] = [];
-  
-  for await (const line of rl) {
-    const task = parse(line);
-    
-    if(task) {
-      list.push(task);
-    }
-  }
-
-  return list;
-}

src/parser/index.ts

@@ -1,15 +0,0 @@
-import {parse as rawParse} from "../generated/grammar/task";
-import { ParseResult } from "../types/grammar/task";
-import { Task } from "../types/task";
-import { LazyTask } from "./task";
-
-export function parse(line: string): Task|undefined {
-  const item = rawParse(line) as ParseResult;
-
-  if (item.type === 'task') {
-    return new LazyTask(item.data);
-  }
-
-  return undefined;
-}
-