feat: add cli command dispatch

Author: tharropoulos

src/cli.ts

@@ -0,0 +1,127 @@
+#!/usr/bin/env node
+
+import { parseArgs } from "node:util";
+import { runExtraction } from "./index.js";
+import { runSemanticDiff } from "./semantic-diff.js";
+import type {
+  CommandLineOptions,
+  SemanticDiffCliOptions,
+  CliOptions,
+} from "./types.js";
+
+async function main(): Promise<void> {
+  const options = parseCli(process.argv.slice(2));
+  if (options.command === "extract") {
+    const spec = await runExtraction(options);
+    if (options.json) {
+      process.stdout.write(
+        `${JSON.stringify({ event: "result", routes: spec.routes.length, diagnostics: spec.diagnostics.length })}\n`,
+      );
+    } else {
+      process.stdout.write(
+        `Extracted ${spec.routes.length} routes with ${spec.diagnostics.length} diagnostics.\n`,
+      );
+    }
+    return;
+  }
+
+  const summary = await runSemanticDiff({
+    previousPath: options.previousPath,
+    nextPath: options.nextPath,
+    jsonOutputPath: options.jsonOutputPath,
+    markdownOutputPath: options.markdownOutputPath,
+  });
+  process.stdout.write(`${JSON.stringify(summary)}\n`);
+}
+
+function parseCli(argv: readonly string[]): CommandLineOptions {
+  const command = argv[0] ?? "extract";
+  const commandArgs = argv[0] === undefined ? argv : argv.slice(1);
+  if (command === "extract") {
+    return parseExtractCli(commandArgs);
+  }
+  if (command === "semantic-diff") {
+    return parseSemanticDiffCli(commandArgs);
+  }
+  throw new Error(`Unknown command: ${command}`);
+}
+function parseExtractCli(argv: readonly string[]): CliOptions {
+  const { values, positionals } = parseArgs({
+    args: [...argv],
+    allowPositionals: true,
+    options: {
+      config: { type: "string" },
+      output: { type: "string" },
+      "base-url": { type: "string" },
+      "max-call-depth": { type: "string" },
+      "fail-on-diagnostics": { type: "boolean" },
+      "fail-on-unresolved": { type: "boolean" },
+      verbose: { type: "boolean" },
+      "debug-route": { type: "string" },
+      json: { type: "boolean" },
+    },
+    strict: true,
+  });
+
+  if (positionals.length > 0) {
+    throw new Error(`Unknown arguments: ${positionals.join(" ")}`);
+  }
+
+  let maxCallDepth: number | undefined;
+  if (values["max-call-depth"] !== undefined) {
+    maxCallDepth = Number.parseInt(values["max-call-depth"], 10);
+    if (!Number.isFinite(maxCallDepth)) {
+      throw new Error(
+        `Invalid value for --max-call-depth: ${values["max-call-depth"]}`,
+      );
+    }
+  }
+
+  return {
+    command: "extract",
+    configPath: values.config,
+    outputPath: values.output,
+    baseUrl: values["base-url"],
+    maxCallDepth,
+    failOnDiagnostics: values["fail-on-diagnostics"],
+    failOnUnresolved: values["fail-on-unresolved"],
+    verbose: values.verbose ?? false,
+    debugRoute: values["debug-route"],
+    json: values.json ?? false,
+  };
+}
+
+function parseSemanticDiffCli(argv: readonly string[]): SemanticDiffCliOptions {
+  const { values, positionals } = parseArgs({
+    args: [...argv],
+    allowPositionals: true,
+    options: {
+      previous: { type: "string" },
+      next: { type: "string" },
+      "json-output": { type: "string" },
+      "markdown-output": { type: "string" },
+    },
+    strict: true,
+  });
+
+  if (positionals.length > 0) {
+    throw new Error(`Unknown arguments: ${positionals.join(" ")}`);
+  }
+  if (values.previous === undefined || values.next === undefined) {
+    throw new Error("Both --previous and --next are required.");
+  }
+
+  return {
+    command: "semantic-diff",
+    previousPath: values.previous,
+    nextPath: values.next,
+    jsonOutputPath: values["json-output"],
+    markdownOutputPath: values["markdown-output"],
+  };
+}
+
+main().catch((error: unknown) => {
+  const message = error instanceof Error ? error.message : String(error);
+  process.stderr.write(`${message}\n`);
+  process.exitCode = 1;
+});