London | 26-SDC-Mar | Ebrahim Beiati-Asl | Sprint 4 | Implement shell python shell tools

implement-shell-tools/implement-shell-tools-python/cat/cat.py

@@ -0,0 +1,53 @@
+#!/usr/bin/env python3
+import sys
+import argparse
+
+
+def print_file(file_path, options, counter):
+    try:
+        with open(file_path, "r", encoding="utf-8") as f:
+            for line in f:
+                stripped = line.rstrip("\n")
+
+                should_number = options.number_mode == "all" or (
+                    options.number_mode == "non-empty" and stripped != ""
+                )
+
+                if should_number:
+                    print(f"{counter}\t{stripped}")
+                    counter += 1
+                else:
+                    print(stripped)
+
+    except FileNotFoundError:
+        print(f"cat: {file_path}: No such file or directory", file=sys.stderr)
+
+    return counter
+
+
+def main():
+    parser = argparse.ArgumentParser(description="Concatenate files and print output")
+    parser.add_argument("-n", "--number", action="store_true", help="number all lines")
+
+    parser.add_argument(
+        "-b", "--number-nonblank", action="store_true", help="number non-empty lines"
+    )
+
+    parser.add_argument("files", nargs="+", help="files to read")
+
+    args = parser.parse_args()
+
+    if args.number_nonblank:
+        args.number_mode = "non-empty"
+    elif args.number:
+        args.number_mode = "all"
+    else:
+        args.number_mode = "none"
+
+    counter = 1
+    for file in args.files:
+        counter = print_file(file, args, counter)
+
+
+if __name__ == "__main__":
+    main()

implement-shell-tools/implement-shell-tools-python/ls/ls.py

@@ -0,0 +1,39 @@
+#!/usr/bin/env python3
+import sys
+import os
+import argparse
+
+
+def list_directory(path, show_all):
+    try:
+        entries = os.listdir(path)
+
+    except Exception as e:
+        print(f"Error reading directory {path}: {e}", file=sys.stderr)
+        sys.exit(1)
+    for entry in sorted(entries):
+        if not show_all and entry.startswith("."):
+            continue
+        print(entry)
+
+
+def main():
+    parser = argparse.ArgumentParser(description="List directory contents")
+    parser.add_argument("-a", "--all", action="store_true", help="show hidden files")
+    parser.add_argument("paths", nargs="*", default=["."], help="directories to list")
+
+    args = parser.parse_args()
+
+    dirs = args.paths
+
+    for i, path in enumerate(dirs):
+        if len(dirs) > 1:
+            print(f"{path}:")
+        list_directory(path, args.all)
+
+        if len(dirs) > 1 and i < len(dirs) - 1:
+            print("")
+
+
+if __name__ == "__main__":
+    main()

implement-shell-tools/implement-shell-tools-python/wc/wc.py

@@ -0,0 +1,70 @@
+#!/usr/bin/env python3
+import sys
+
+def count_file_content(content):
+    raw_lines = content.split("\n")
+    lines = len(raw_lines) - 1 if raw_lines[-1] == "" else len(raw_lines)
+    words = len(content.split())
+    bytes_ = len(content.encode("utf-8"))
+    return lines, words, bytes_
+
+
+def print_counts(path, counts, options):
+    parts = []
+    if options["line"]:
+        parts.append(str(counts[0]).rjust(8))
+    if options["word"]:
+        parts.append(str(counts[1]).rjust(8))
+    if options["byte"]:
+        parts.append(str(counts[2]).rjust(8))
+
+    output = "".join(parts)
+    print(f"{output} {path}")
+
+
+def main():
+    args = sys.argv[1:]
+
+    options = {"line": False, "word": False, "byte": False}
+    files = []
+
+    for arg in args:
+        if arg == "-l":
+            options["line"] = True
+        elif arg == "-w":
+            options["word"] = True
+        elif arg == "-c":
+            options["byte"] = True
+        else:
+            files.append(arg)
+
+    if not files:
+        print("No files specified", file=sys.stderr)
+        sys.exit(1)
+
+    if not any(options.values()):
+        options = {"line": True, "word": True, "byte": True}
+
+    total = [0, 0, 0]
+    multiple = len(files) > 1
+
+    for path in files:
+        try:
+            with open(path, "r", encoding="utf-8") as f:
+                content = f.read()
+
+            counts = count_file_content(content)
+            total = [t + c for t, c in zip(total, counts)]
+
+            print_counts(path, counts, options)
+
+        except Exception as e:
+            print(f"Error reading file {path}: {e}", file=sys.stderr)
+            sys.exit(1)
+
+    if multiple:
+        print_counts("total", total, options)
+
+
+if __name__ == "__main__":
+    main()