extension.js

const vscode = require('vscode')
const { execFile } = require('child_process')
const fs = require('fs')
const path = require('path')

let cachedCli = null

function detectClaude() {
	return new Promise((resolve) => {
		const finder = process.platform === 'win32' ? 'where' : 'which'
		execFile(finder, ['claude'], { timeout: 5000 }, (err, stdout) => {
			if (err || !stdout) return resolve(null)
			const lines = String(stdout)
				.split(/\r?\n/)
				.map((s) => s.trim())
				.filter(Boolean)
			if (!lines.length) return resolve(null)
			if (process.platform !== 'win32') return resolve(lines[0])

			// On Windows, npm installs three shims (claude, claude.cmd, claude.ps1).
			// The extensionless one is a Unix shell script and the .cmd needs cmd.exe,
			// so Node can't execFile them and pipe stdin reliably. Prefer the real exe.
			const exe = lines.find((l) => l.toLowerCase().endsWith('.exe'))
			if (exe) return resolve(exe)
			// Derive claude.exe from any shim's directory (the npm global prefix).
			const shim = lines.find((l) => l.toLowerCase().endsWith('.cmd')) || lines[0]
			const exePath = path.join(
				path.dirname(shim),
				'node_modules', '@anthropic-ai', 'claude-code', 'bin', 'claude.exe',
			)
			if (fs.existsSync(exePath)) return resolve(exePath)
			// Fall back to the .cmd shim if present, else whatever we got.
			const cmd = lines.find((l) => l.toLowerCase().endsWith('.cmd'))
			return resolve(cmd || lines[0])
		})
	})
}

async function resolveCli() {
	const configured = vscode.workspace.getConfiguration('claudeCommitButton').get('cliPath')
	if (configured && configured.trim()) return configured.trim()
	if (cachedCli && fs.existsSync(cachedCli)) return cachedCli
	const found = await detectClaude()
	if (found) {
		cachedCli = found
		return found
	}
	return 'claude'
}

function activate(context) {
	const disposable = vscode.commands.registerCommand('claudeCommitButton.generate', async (arg) => {
		const gitExt = vscode.extensions.getExtension('vscode.git')
		const git = gitExt && gitExt.exports && gitExt.exports.getAPI(1)
		if (!git) {
			vscode.window.showErrorMessage('Git extension not found.')
			return
		}

		// Resolve the repository (the scm menu passes the SourceControl as arg)
		let repo = null
		if (arg && arg.rootUri) {
			repo = git.repositories.find((r) => r.rootUri.toString() === arg.rootUri.toString())
		}
		if (!repo) repo = git.repositories[0]
		if (!repo) {
			vscode.window.showErrorMessage('No Git repository.')
			return
		}

		// Diff: staged first, fall back to working tree
		let diff = await repo.diff(true)
		if (!diff || !diff.trim()) diff = await repo.diff(false)
		if (!diff || !diff.trim()) {
			vscode.window.showWarningMessage('No changes.')
			return
		}

		const MAX = 6000
		if (diff.length > MAX) diff = diff.slice(0, MAX) + '\n...[truncated]'

		const cfg = vscode.workspace.getConfiguration('claudeCommitButton')
		const claudePath = await resolveCli()
		const model = cfg.get('model') || 'sonnet'
		const effort = cfg.get('effort') || 'low'

		const prompt =
			'Write a concise git commit message for the diff below. ' +
			'Imperative mood, conventional style. ' +
			'Reply with the message only (short subject line; blank line and brief body if needed). ' +
			'No backticks, no explanation, no surrounding quotes.\n\nDIFF:\n' +
			diff

		await vscode.window.withProgress(
			{ location: vscode.ProgressLocation.SourceControl, title: 'Claude: generating…' },
			() =>
				new Promise((resolve) => {
					const args = [
						'-p',
						'--model',
						model,
						'--effort',
						effort,
						'--no-session-persistence',
						'--tools',
						'',
						'--strict-mcp-config',
						'--setting-sources',
						'',
						'--dangerously-skip-permissions',
					]
					const child = execFile(
						claudePath,
						args,
						{ maxBuffer: 10 * 1024 * 1024, cwd: repo.rootUri.fsPath },
						(err, stdout, stderr) => {
							if (err) {
								const detail = stderr || err.message
								const notFound = /ENOENT/.test(detail)
								const hint = notFound
									? ' — Claude CLI not found on PATH. Set "claudeCommitButton.cliPath" to your claude executable (on Windows, the claude.exe; if Claude is installed under WSL or Git Bash it won\'t be on the Windows PATH).'
									: ''
								vscode.window.showErrorMessage('Claude failed: ' + detail + hint)
								resolve()
								return
							}
							const msg = (stdout || '').trim()
							if (msg) {
								repo.inputBox.value = msg
							} else {
								vscode.window.showWarningMessage('Claude returned empty.')
							}
							resolve()
						},
					)
					// If the CLI can't be spawned (e.g. wrong path), stdin emits an
					// error; swallow it so the execFile callback reports the real cause.
					child.stdin.on('error', () => {})
					child.stdin.write(prompt)
					child.stdin.end()
				}),
		)
	})

	context.subscriptions.push(disposable)
}

function deactivate() {}

module.exports = { activate, deactivate }