London | 25-SDC-July | Franklin Kamela | Sprint 3 | Feature/Implement Shell Tools

implement-shell-tools/cat/my_cat.js

@@ -0,0 +1,41 @@
+import { promises as fs } from 'node:fs';
+import { argv } from 'node:process';
+
+const args = argv.slice(2); // skip node and script name
+
+let showLineNumb = false;
+let showNoBlankNumb = false
+let file = '';
+
+
+args.forEach(arg => {
+  if (arg === '-n') {
+    showLineNumb = true;
+  } else if (arg === '-b') {
+    showLineNumb = false;
+    showNoBlankNumb = true;
+  }else {  
+    file = arg; 
+  }
+});
+
+try {
+  let content = await fs.readFile(file, 'utf-8');
+  const lines = content.split('\n');
+
+  if (showLineNumb) {
+    // Number all lines
+    content = lines.map((line, i) => `${i + 1}\t${line}`).join('\n');
+  }else  if (showNoBlankNumb) {
+    // Number only non-blank lines
+    let counter = 1;
+    content = lines.map(line => {
+      if (line.trim() === '') return '';
+      return `${counter++}\t${line}`;
+    }).join('\n');
+  }
+
+  console.log (content)
+} catch (err) {
+  console.error(`Cannot access '${file}': ${err.message}`);
+}

implement-shell-tools/ls/my_ls.js

@@ -0,0 +1,29 @@
+import { readdirSync } from 'node:fs';
+import { argv } from 'node:process';
+
+const args = argv.slice(2); // skip node and script name
+
+let showAll = false;
+let dir = '.'; //set dir to current directory
+
+// Parse args to check weather or not to show hidden files
+//and ignore -1 because our output is already 1 per line
+args.forEach(arg => {
+  if (arg === '-a') {
+    showAll = true;
+  } else if (arg !== '-1') {
+    dir = arg; //assumes anything else is our target directory
+  }
+});
+
+try {
+  let files = readdirSync(dir); // Reads the contents of the dir synchronously (readdirSync)
+
+  if (!showAll) {
+    files = files.filter(file => !file.startsWith('.'));
+  }
+
+  files.forEach(file => console.log(file));
+} catch (err) {
+  console.error(`Cannot access '${dir}': ${err.message}`);
+}

implement-shell-tools/wc/my_wc.js

@@ -0,0 +1,89 @@
+import { promises as fs } from 'node:fs';
+import { argv } from 'node:process';
+
+const args = argv.slice(2);
+
+if (args.length === 0) {
+  console.error('Usage: node my_wc.mjs [-l] [-w] [-c] <file> [file2 ...]');
+  process.exit(1);
+}
+
+// Parse flags and files
+const flags = {
+  l: false,
+  w: false,
+  c: false,
+};
+
+const files = [];
+
+for (const arg of args) {
+  if (arg.startsWith('-') && arg.length > 1) {
+    for (const ch of arg.slice(1)) {
+      if (flags.hasOwnProperty(ch)) {
+        flags[ch] = true;
+      } else {
+        console.error(`Unknown option: -${ch}`);
+        process.exit(1);
+      }
+    }
+  } else {
+    files.push(arg);
+  }
+}
+
+if (files.length === 0) {
+  console.error('Error: no files specified.');
+  process.exit(1);
+}
+
+// If no flags specified, show all by default
+const showLines = flags.l || (!flags.l && !flags.w && !flags.c);
+const showWords = flags.w || (!flags.l && !flags.w && !flags.c);
+const showBytes = flags.c || (!flags.l && !flags.w && !flags.c);
+
+async function countFile(file) {
+  try {
+    const content = await fs.readFile(file, 'utf-8');
+    const lines = content.split('\n').filter(line => line.trim() !== '').length;
+    const words = content.trim().split(/\s+/).filter(Boolean).length;
+    const bytes = Buffer.byteLength(content, 'utf-8');
+
+    let output = '';
+    if (showLines) output += `${lines} `;
+    if (showWords) output += `${words} `;
+    if (showBytes) output += `${bytes} `;
+
+    output += file;
+
+    console.log(output.trim());
+
+    return { lines, words, bytes };
+  } catch (err) {
+    console.error(`Cannot access '${file}': ${err.message}`);
+    return null;
+  }
+}
+
+async function main() {
+  const counts = await Promise.all(files.map(countFile));
+
+  const validCounts = counts.filter(c => c !== null);
+
+  if (validCounts.length > 1) {
+    const totalLines = validCounts.reduce((sum, c) => sum + c.lines, 0);
+    const totalWords = validCounts.reduce((sum, c) => sum + c.words, 0);
+    const totalBytes = validCounts.reduce((sum, c) => sum + c.bytes, 0);
+
+    let totalOutput = '';
+    if (showLines) totalOutput += `${totalLines} `;
+    if (showWords) totalOutput += `${totalWords} `;
+    if (showBytes) totalOutput += `${totalBytes} `;
+
+    totalOutput += 'total';
+
+    console.log(totalOutput.trim());
+  }
+}
+
+main();