# Phase 4: Pi-hole Integration

**Status:** ⬜ Not Started
**Parent plan:** [PLAN.md](./PLAN.md)
**Domain:** backend

## Objective
Implement Pi-hole integration using its admin API to display DNS blocking statistics, top blocked domains, and query logs.

## Tasks

- [ ] Task 1: Create `src/lib/server/integrations/pihole/schema.ts` — Zod schemas for auth config (`{ apiToken: string }`) and endpoint responses (summary stats, top items, query log).
- [ ] Task 2: Create `src/lib/server/integrations/pihole/client.ts` — HTTP client for Pi-hole API. Endpoints: `{app.url}/admin/api.php?summary`, `?topItems=N`, `?getAllQueries=N`, `?getQuerySources`. Include auth token as `&auth=<token>`.
- [ ] Task 3: Create `src/lib/server/integrations/pihole/transform.ts` — Transform API responses: summary → stat-card data (total queries, blocked, block %, clients), topItems → list data, queries → list with allow/block indicator.
- [ ] Task 4: Create `src/lib/server/integrations/pihole/index.ts` — Integration implementation. Endpoints: `stats-summary` (stat-card), `top-blocked` (list), `query-log` (list), `gravity-status` (stat-card). testConnection: fetch summary endpoint.
- [ ] Task 5: Register Pi-hole integration in registry.

## Files to Modify/Create
- `src/lib/server/integrations/pihole/schema.ts` — new
- `src/lib/server/integrations/pihole/client.ts` — new
- `src/lib/server/integrations/pihole/transform.ts` — new
- `src/lib/server/integrations/pihole/index.ts` — new
- `src/lib/server/integrations/registry.ts` — modify: register Pi-hole

## Acceptance Criteria
- Stats summary shows: total queries, blocked queries, block percentage, unique clients
- Top blocked domains list with counts
- Query log with domain, client, allow/block status
- Gravity status shows last update time and blocklist count
- Test connection validates API token
- Handles Pi-hole v5 and v6 API differences gracefully

## Notes
- Pi-hole API is simple GET-based with auth token as query parameter
- Some endpoints require authentication (topItems, queries), summary is often public
- Response format is flat JSON — easy to parse
- Consider Pi-hole v6 (new API format) — detect version and adapt

## Review Checklist
- [ ] All tasks completed
- [ ] API responses properly validated
- [ ] Code follows project conventions

## Handoff to Next Phase
<!-- Filled in after completion -->