feat(coding-agent,tui): add stacked autocomplete providers closes #2983

packages/coding-agent/examples/extensions/github-issue-autocomplete.ts

@@ -0,0 +1,185 @@
+// Requires GitHub CLI (`gh`) and a GitHub repository checkout.
+// Preloads the latest open issues once per session, then filters them locally for fast `#...` completion.
+
+import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import {
+	type AutocompleteItem,
+	type AutocompleteProvider,
+	type AutocompleteSuggestions,
+	fuzzyFilter,
+} from "@mariozechner/pi-tui";
+
+type GitHubIssue = {
+	number: number;
+	title: string;
+	state: string;
+};
+
+type RepoResolution = { ok: true; repo: string } | { ok: false; error: string };
+
+const MAX_ISSUES = 100;
+const MAX_SUGGESTIONS = 20;
+
+function extractIssueToken(textBeforeCursor: string): string | undefined {
+	const match = textBeforeCursor.match(/(?:^|[ \t])#([^\s#]*)$/);
+	return match?.[1];
+}
+
+function parseGitHubRepo(remoteUrl: string): string | undefined {
+	const sshMatch = remoteUrl.match(/^git@github\.com:([^/]+\/[^/]+?)(?:\.git)?$/);
+	if (sshMatch) {
+		return sshMatch[1];
+	}
+
+	const httpsMatch = remoteUrl.match(/^https?:\/\/github\.com\/([^/]+\/[^/]+?)(?:\.git)?$/);
+	if (httpsMatch) {
+		return httpsMatch[1];
+	}
+
+	return undefined;
+}
+
+async function resolveGitHubRepo(pi: ExtensionAPI, cwd: string): Promise<RepoResolution> {
+	const result = await pi.exec("git", ["remote", "-v"], { cwd, timeout: 5_000 });
+	if (result.code !== 0) {
+		return { ok: false, error: "github-issue-autocomplete: cwd is not a git repository" };
+	}
+
+	for (const line of result.stdout.split("\n")) {
+		const columns = line.trim().split(/\s+/);
+		const remoteUrl = columns[1];
+		if (!remoteUrl) {
+			continue;
+		}
+		const repo = parseGitHubRepo(remoteUrl);
+		if (repo) {
+			return { ok: true, repo };
+		}
+	}
+
+	return { ok: false, error: "github-issue-autocomplete: cwd is not a GitHub repository" };
+}
+
+function formatIssueItem(issue: GitHubIssue): AutocompleteItem {
+	return {
+		value: `#${issue.number}`,
+		label: `#${issue.number}`,
+		description: `[${issue.state.toLowerCase()}] ${issue.title}`,
+	};
+}
+
+function filterIssues(issues: GitHubIssue[], query: string): AutocompleteItem[] {
+	if (!query.trim()) {
+		return issues.slice(0, MAX_SUGGESTIONS).map(formatIssueItem);
+	}
+
+	if (/^\d+$/.test(query)) {
+		const numericMatches = issues
+			.filter((issue) => String(issue.number).startsWith(query))
+			.slice(0, MAX_SUGGESTIONS)
+			.map(formatIssueItem);
+		if (numericMatches.length > 0) {
+			return numericMatches;
+		}
+	}
+
+	return fuzzyFilter(issues, query, (issue) => `${issue.number} ${issue.title}`)
+		.slice(0, MAX_SUGGESTIONS)
+		.map(formatIssueItem);
+}
+
+function createIssueAutocompleteProvider(
+	current: AutocompleteProvider,
+	getIssues: () => Promise<GitHubIssue[] | undefined>,
+): AutocompleteProvider {
+	return {
+		async getSuggestions(lines, cursorLine, cursorCol, options): Promise<AutocompleteSuggestions | null> {
+			const currentLine = lines[cursorLine] ?? "";
+			const textBeforeCursor = currentLine.slice(0, cursorCol);
+			const token = extractIssueToken(textBeforeCursor);
+			if (token === undefined) {
+				return current.getSuggestions(lines, cursorLine, cursorCol, options);
+			}
+
+			const issues = await getIssues();
+			if (options.signal.aborted || !issues || issues.length === 0) {
+				return current.getSuggestions(lines, cursorLine, cursorCol, options);
+			}
+
+			const suggestions = filterIssues(issues, token);
+			if (suggestions.length === 0) {
+				return current.getSuggestions(lines, cursorLine, cursorCol, options);
+			}
+
+			return {
+				items: suggestions,
+				prefix: `#${token}`,
+			};
+		},
+
+		applyCompletion(lines, cursorLine, cursorCol, item, prefix) {
+			return current.applyCompletion(lines, cursorLine, cursorCol, item, prefix);
+		},
+
+		shouldTriggerFileCompletion(lines, cursorLine, cursorCol) {
+			return current.shouldTriggerFileCompletion?.(lines, cursorLine, cursorCol) ?? true;
+		},
+	};
+}
+
+export default function (pi: ExtensionAPI): void {
+	pi.on("session_start", async (_event, ctx) => {
+		const resolvedRepo = await resolveGitHubRepo(pi, ctx.cwd);
+		if (!resolvedRepo.ok) {
+			ctx.ui.notify(resolvedRepo.error, "error");
+			return;
+		}
+
+		const repo = resolvedRepo.repo;
+		let issuesPromise: Promise<GitHubIssue[] | undefined> | undefined;
+		let loadErrorShown = false;
+
+		const getIssues = async (): Promise<GitHubIssue[] | undefined> => {
+			issuesPromise ||= (async () => {
+				const result = await pi.exec(
+					"gh",
+					[
+						"issue",
+						"list",
+						"--repo",
+						repo,
+						"--state",
+						"open",
+						"--limit",
+						String(MAX_ISSUES),
+						"--json",
+						"number,title,state",
+					],
+					{ cwd: ctx.cwd, timeout: 5_000 },
+				);
+				if (result.code !== 0) {
+					if (!loadErrorShown) {
+						loadErrorShown = true;
+						const details = result.stderr.trim() || `exit code ${result.code}`;
+						ctx.ui.notify(`github-issue-autocomplete: failed to load issues: ${details}`, "error");
+					}
+					return undefined;
+				}
+
+				try {
+					return JSON.parse(result.stdout) as GitHubIssue[];
+				} catch {
+					if (!loadErrorShown) {
+						loadErrorShown = true;
+						ctx.ui.notify("github-issue-autocomplete: failed to parse gh issue list output", "error");
+					}
+					return undefined;
+				}
+			})();
+			return issuesPromise;
+		};
+
+		void getIssues();
+		ctx.ui.addAutocompleteProvider((current) => createIssueAutocompleteProvider(current, getIssues));
+	});
+}