feat: finish phase 3 Gen Command Implementation

Author: wislertt

.amazonq/plans/cli-implementation.md

@@ -0,0 +1,68 @@
+from pathlib import Path
+
+import typer
+
+from leetcode_py.tools.generator import generate_problem
+
+from ..utils.problem_finder import find_problem_by_number, find_problems_by_tag, get_problem_json_path
+from ..utils.resources import get_template_path
+
+
+def resolve_problems(
+    problem_num: int | None, problem_slug: str | None, problem_tag: str | None
+) -> list[str]:
+    if problem_num is not None:
+        problem_name = find_problem_by_number(problem_num)
+        if not problem_name:
+            typer.echo(f"Error: Problem number {problem_num} not found", err=True)
+            raise typer.Exit(1)
+        return [problem_name]
+    elif problem_slug is not None:
+        return [problem_slug]
+    elif problem_tag is not None:
+        problems = find_problems_by_tag(problem_tag)
+        if not problems:
+            typer.echo(f"Error: No problems found with tag '{problem_tag}'", err=True)
+            raise typer.Exit(1)
+        typer.echo(f"Found {len(problems)} problems with tag '{problem_tag}'")
+        return problems
+
+    typer.echo(
+        "Error: Exactly one of --problem-num, --problem-slug, or --problem-tag is required", err=True
+    )
+    raise typer.Exit(1)
+
+
+def generate(
+    problem_num: int | None = typer.Option(None, "-n", "--problem-num", help="Problem number"),
+    problem_slug: str | None = typer.Option(None, "-s", "--problem-slug", help="Problem slug"),
+    problem_tag: str | None = typer.Option(None, "-t", "--problem-tag", help="Problem tag (bulk)"),
+    output: str = typer.Option("leetcode", "-o", "--output", help="Output directory"),
+    force: bool = typer.Option(False, "--force", help="Force overwrite existing files"),
+):
+    options_provided = sum(x is not None for x in [problem_num, problem_slug, problem_tag])
+    if options_provided != 1:
+        typer.echo(
+            "Error: Exactly one of --problem-num, --problem-slug, or --problem-tag is required", err=True
+        )
+        raise typer.Exit(1)
+
+    template_dir = get_template_path()
+    output_dir = Path(output)
+
+    # Determine which problems to generate
+    problems = resolve_problems(problem_num, problem_slug, problem_tag)
+
+    # Generate each problem
+    for problem_name in problems:
+        json_path = get_problem_json_path(problem_name)
+        if not json_path.exists():
+            typer.echo(f"Warning: JSON file not found for problem '{problem_name}', skipping", err=True)
+            continue
+
+        try:
+            generate_problem(json_path, template_dir, output_dir, force)
+        except Exception as e:
+            typer.echo(f"Error generating problem '{problem_name}': {e}", err=True)
+            if len(problems) == 1:
+                raise typer.Exit(1)

leetcode_py/cli/commands/gen.py

@@ -2,9 +2,9 @@
 
 import typer
 
-app = typer.Typer(
-    help="LeetCode problem generator - Generate and list LeetCode problems",
-)
+from .commands.gen import generate
+
+app = typer.Typer(help="LeetCode problem generator - Generate and list LeetCode problems")
 
 
 def show_version():
@@ -25,10 +25,7 @@ def main_callback(
         raise typer.Exit()
 
 
-# Placeholder commands for Phase 1 testing
-@app.command()
-def gen():
-    typer.echo("gen command - coming soon!")
+app.command(name="gen")(generate)
 
 
 @app.command()