import { Hono } from "hono";
import { cors } from "hono/cors";
import { createWorker } from "@atmo-dev/contrail/worker";
import { Contrail } from "@atmo-dev/contrail";
import { config } from "./contrail.config.js";
import { lexicons } from "../lexicons/generated/index.js";
import { LANDING_PAGE } from "./landing-page.js";
import { StrataContainer } from "./container.js";

// ─── Env ────────────────────────────────────────────────────────────

interface Env {
  DB: D1Database;
  VAULT_BUCKET: R2Bucket;
  CARRY_BUCKET: R2Bucket;
  STRATA_CONTAINER: DurableObjectNamespace;
}

// ─── Contrail setup ─────────────────────────────────────────────────

const contrailWorker = createWorker(config, { lexicons });
const contrail = new Contrail(config);
let contrailReady = false;

async function ensureContrailReady(db: D1Database): Promise<void> {
  if (contrailReady) return;
  await contrail.init(db);
  contrailReady = true;
}

// ─── Island detection (connected components) ────────────────────────
//
// Load all connections, build an undirected graph, find connected
// components via BFS. Each component is an "island" — a cluster of
// linked URLs that form a constellation in the knowledge graph.

interface Island {
  id: string;
  vertices: string[];
  edges: Array<{
    uri: string;
    did: string;
    source: string;
    target: string;
    connectionType: string;
    note: string;
    handle?: string | null;
  }>;
}

async function detectIslands(db: D1Database): Promise<Island[]> {
  await ensureContrailReady(db);

  // Load all connections
  const rows = await db
    .prepare(
      `SELECT r.record, r.did, r.rkey, i.handle
       FROM records_connection r
       LEFT JOIN identities i ON r.did = i.did
       ORDER BY r.time_us DESC`,
    )
    .all<{ record: string; did: string; rkey: string; handle: string | null }>();

  // Build adjacency list
  const adj = new Map<string, Set<string>>();
  const edges: Island["edges"] = [];

  for (const row of rows.results || []) {
    try {
      const value = JSON.parse(row.record);
      const source = value.source as string;
      const target = value.target as string;
      if (!source || !target) continue;

      if (!adj.has(source)) adj.set(source, new Set());
      if (!adj.has(target)) adj.set(target, new Set());
      adj.get(source)!.add(target);
      adj.get(target)!.add(source);

      edges.push({
        uri: `at://${row.did}/network.cosmik.connection/${row.rkey}`,
        did: row.did,
        source,
        target,
        connectionType: value.connectionType || "relates",
        note: value.note || "",
        handle: row.handle,
      });
    } catch {}
  }

  // BFS to find connected components
  const visited = new Set<string>();
  const islands: Island[] = [];

  for (const node of adj.keys()) {
    if (visited.has(node)) continue;

    const component: string[] = [];
    const queue = [node];
    while (queue.length > 0) {
      const current = queue.shift()!;
      if (visited.has(current)) continue;
      visited.add(current);
      component.push(current);

      for (const neighbor of adj.get(current) || []) {
        if (!visited.has(neighbor)) queue.push(neighbor);
      }
    }

    // Only include edges where both endpoints are in this component
    const componentSet = new Set(component);
    const componentEdges = edges.filter(
      e => componentSet.has(e.source) && componentSet.has(e.target),
    );

    // Stable ID: truncated SHA-256 of the lexicographic minimum vertex
    const lexmin = component.sort()[0];
    const lexminHash = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(lexmin));
    const id = Array.from(new Uint8Array(lexminHash)).map(b => b.toString(16).padStart(2, "0")).join("").slice(0, 16);

    islands.push({
      id,
      vertices: component,
      edges: componentEdges,
    });
  }

  // Sort by size descending
  islands.sort((a, b) => b.vertices.length - a.vertices.length);
  return islands;
}

// ─── Resolve vertex metadata (batched) ──────────────────────────────
//
// Bulk queries instead of N+1 per vertex. Loads all cards and citations
// matching the given URIs in a few chunked queries.

async function resolveVertexMeta(
  db: D1Database,
  uris: string[],
): Promise<Map<string, { title: string; description: string; type: string }>> {
  const meta = new Map<string, { title: string; description: string; type: string }>();
  for (const uri of uris) {
    meta.set(uri, { title: uri, description: "", type: "unknown" });
  }

  const httpUris = uris.filter(u => u.startsWith("http"));
  const atUris = uris.filter(u => u.startsWith("at://"));
  const CHUNK = 50;

  // ── Resolve HTTP URIs (existing logic) ──

  // Batch card lookup
  for (let i = 0; i < httpUris.length; i += CHUNK) {
    const chunk = httpUris.slice(i, i + CHUNK);
    const placeholders = chunk.map(() => "?").join(",");
    const rows = await db
      .prepare(
        `SELECT record FROM records_card
         WHERE json_extract(record, '$.content.url') IN (${placeholders})`,
      )
      .bind(...chunk)
      .all<{ record: string }>();

    for (const row of rows.results || []) {
      try {
        const card = JSON.parse(row.record);
        const url = card?.content?.url;
        if (!url || !meta.has(url)) continue;
        const m = card.content.metadata;
        if (m?.title || m?.description) {
          meta.set(url, {
            title: m.title || url,
            description: m.description || "",
            type: card.type === "URL" ? "url" : "note",
          });
        }
      } catch {}
    }
  }

  // Batch citation lookup (overrides card data if found)
  for (let i = 0; i < httpUris.length; i += CHUNK) {
    const chunk = httpUris.slice(i, i + CHUNK);
    const placeholders = chunk.map(() => "?").join(",");
    const rows = await db
      .prepare(
        `SELECT record FROM records_citation
         WHERE json_extract(record, '$.url') IN (${placeholders})`,
      )
      .bind(...chunk)
      .all<{ record: string }>();

    for (const row of rows.results || []) {
      try {
        const citation = JSON.parse(row.record);
        const url = citation.url;
        if (!url || !meta.has(url)) continue;
        if (citation.title) {
          const existing = meta.get(url)!;
          meta.set(url, {
            title: citation.title,
            description: citation.takeaway || existing.description,
            type: "citation",
          });
        }
      } catch {}
    }
  }

  // ── Resolve AT URIs ──

  // Batch card lookup by AT URI
  for (let i = 0; i < atUris.length; i += CHUNK) {
    const chunk = atUris.slice(i, i + CHUNK);
    const placeholders = chunk.map(() => "?").join(",");
    const rows = await db
      .prepare(`SELECT uri, record FROM records_card WHERE uri IN (${placeholders})`)
      .bind(...chunk)
      .all<{ uri: string; record: string }>();

    for (const row of rows.results || []) {
      try {
        const card = JSON.parse(row.record);
        const m = card?.content?.metadata;
        const url = card?.content?.url;
        if (meta.has(row.uri)) {
          meta.set(row.uri, {
            title: m?.title || url || row.uri,
            description: m?.description || "",
            type: "card",
          });
        }
      } catch {}
    }
  }

  // Batch collection lookup by AT URI
  for (let i = 0; i < atUris.length; i += CHUNK) {
    const chunk = atUris.slice(i, i + CHUNK);
    const placeholders = chunk.map(() => "?").join(",");
    const rows = await db
      .prepare(`SELECT uri, record FROM records_collection WHERE uri IN (${placeholders})`)
      .bind(...chunk)
      .all<{ uri: string; record: string }>();

    for (const row of rows.results || []) {
      try {
        const coll = JSON.parse(row.record);
        if (meta.has(row.uri)) {
          meta.set(row.uri, {
            title: coll.name || row.uri,
            description: coll.description || "",
            type: "collection",
          });
        }
      } catch {}
    }
  }

  return meta;
}

// ─── Derive island from lexmin ────────────────────────────────────
//
// Given a lexmin vertex (canonical component reference), derive the
// connected component by traversing network.cosmik.connection records.

async function deriveIsland(
  db: D1Database,
  seed: string,
): Promise<Island | null> {
  await ensureContrailReady(db);

  // BFS in application code — recursive CTE OOMs in D1 due to cross join
  const visited = new Set<string>();
  const queue = [seed];
  const allEdges: Array<{
    uri: string; did: string; rkey: string;
    source: string; target: string; connectionType: string;
    note: string; handle: string | null;
  }> = [];

  while (queue.length > 0) {
    // Drain the current queue into a batch
    const batch = queue.splice(0, 50);
    const toQuery = batch.filter(v => !visited.has(v));
    if (toQuery.length === 0) continue;

    // Mark visited
    for (const v of toQuery) visited.add(v);

    // Query connections where any of these vertices are source or target
    const placeholders = toQuery.map(() => "?").join(",");
    const rows = await db
      .prepare(
        `SELECT r.record, r.did, r.rkey, i.handle
         FROM records_connection r
         LEFT JOIN identities i ON r.did = i.did
         WHERE json_extract(r.record, '$.source') IN (${placeholders})
            OR json_extract(r.record, '$.target') IN (${placeholders})`,
      )
      .bind(...toQuery, ...toQuery)
      .all<{ record: string; did: string; rkey: string; handle: string | null }>();

    for (const row of rows.results || []) {
      try {
        const value = JSON.parse(row.record);
        const source = value.source as string;
        const target = value.target as string;
        if (!source || !target) continue;

        // Collect edge
        const edgeKey = `${source}|${target}|${row.rkey}`;
        allEdges.push({
          uri: `at://${row.did}/network.cosmik.connection/${row.rkey}`,
          did: row.did,
          rkey: row.rkey,
          source,
          target,
          connectionType: value.connectionType || "relates",
          note: value.note || "",
          handle: row.handle,
        });

        // Enqueue unvisited neighbors
        if (!visited.has(source)) queue.push(source);
        if (!visited.has(target)) queue.push(target);
      } catch {}
    }
  }

  if (visited.size === 0) return null;

  const vertices = [...visited];

  // Filter edges to only those with both endpoints in the component
  const vertexSet = new Set(vertices);
  const edges: Island["edges"] = [];
  const seenEdges = new Set<string>();
  for (const e of allEdges) {
    if (!vertexSet.has(e.source) || !vertexSet.has(e.target)) continue;
    const edgeKey = `${e.source}|${e.target}|${e.rkey}`;
    if (seenEdges.has(edgeKey)) continue;
    seenEdges.add(edgeKey);
    edges.push({
      uri: e.uri,
      did: e.did,
      source: e.source,
      target: e.target,
      connectionType: e.connectionType,
      note: e.note,
      handle: e.handle,
    });
  }

  // Compute stable ID from lexmin
  const sortedVertices = [...vertices].sort();
  const actualLexmin = sortedVertices[0];
  const lexminHash = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(actualLexmin));
  const id = Array.from(new Uint8Array(lexminHash)).map(b => b.toString(16).padStart(2, "0")).join("").slice(0, 16);

  return { id, vertices, edges };
}

// ─── List strata islands from records_strata ──────────────────────

// ─── Hono app ───────────────────────────────────────────────────────

let app: Hono<{ Bindings: Env }> | null = null;

function buildApp(env: Env): Hono<{ Bindings: Env }> {
  const app = new Hono<{ Bindings: Env }>();
  const db = env.DB;

  app.use("*", cors());

  // Landing page — strata records feed
  app.get("/", async (c) => {
    // Load only the fields we need — records are 100KB+ with embedded connections
    // No ensureContrailReady needed — just D1
    let islandsJson = "[]";
    try {
      const rows = await db
        .prepare("SELECT uri, json_extract(record, '$.source.uri') as lexmin, json_extract(record, '$.analysis.title') as title FROM records_strata ORDER BY time_us DESC LIMIT 10")
        .all<{ uri: string; lexmin: string | null; title: string | null }>();

      const islands: any[] = [];
      for (const row of rows.results || []) {
        if (!row.lexmin) continue;
        const lexminHash = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(row.lexmin));
        const id = Array.from(new Uint8Array(lexminHash)).map(b => b.toString(16).padStart(2, "0")).join("").slice(0, 16);
        islands.push({ id, lexmin: row.lexmin, title: row.title || null, recordUri: row.uri });
      }
      islandsJson = JSON.stringify(islands);
    } catch (e) {
      console.error("Failed to load islands:", e);
    }

    const page = LANDING_PAGE.replace(
      "</head>",
      `<script>window.__ISLANDS__=${islandsJson};</script></head>`,
    );
    return c.html(page);
  });

  // ── Islands API ──────────────────────────────────────────────────

  app.get("/xrpc/org.latha.strata.getIslands", async (c) => {
    const limit = Math.min(parseInt(c.req.query("limit") || "50"), 100);
    await ensureContrailReady(db);

    const rows = await db
      .prepare("SELECT uri, record FROM records_strata ORDER BY time_us DESC LIMIT ?")
      .bind(limit)
      .all<{ uri: string; record: string }>();

    const islands: any[] = [];
    for (const row of rows.results || []) {
      try {
        const rec = JSON.parse(row.record);
        const lexmin = rec.source?.uri;
        if (!lexmin) continue;

        const lexminHash = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(lexmin));
        const id = Array.from(new Uint8Array(lexminHash)).map(b => b.toString(16).padStart(2, "0")).join("").slice(0, 16);

        // Build graph directly from embedded connections — no D1 lookups needed
        const connections: any[] = rec.connections || [];
        const vertexSet = new Set<string>();
        const edges: any[] = [];

        for (const conn of connections) {
          if (typeof conn === "object" && conn.source && conn.target) {
            vertexSet.add(conn.source);
            vertexSet.add(conn.target);
            edges.push(conn);
          }
        }

        const vertices = [...vertexSet].sort();
        const vertexMeta = Object.fromEntries(await resolveVertexMeta(db, vertices));

        const analysis = rec.analysis || {};
        islands.push({
          id, lexmin, vertices, edges, vertexMeta,
          title: analysis.title || null,
          strata: analysis.synthesis ? {
            prose: analysis.synthesis || "", title: analysis.title || "",
            themes: analysis.themes || [],
            relationships: (analysis.connections || []).map((conn: any) => conn.description || ""),
            tensions: analysis.tensions || [],
            open_questions: analysis.openQuestions || [],
            synthesis: analysis.synthesis || "",
          } : null,
          recordUri: row.uri,
        });
      } catch {}
    }

    return c.json({ islands });
  });

  // ── Get single island by ID or AT URI ────────────────────────────

  app.get("/xrpc/org.latha.strata.getIsland", async (c) => {
    const id = c.req.query("id");
    if (!id) {
      return c.json({ error: "MissingRequiredParameter", message: "id is required" }, 400);
    }

    await ensureContrailReady(db);

    // If it's an AT URI, look up the strata record and derive from its lexmin
    if (id.startsWith("at://")) {
      const row = await db
        .prepare("SELECT uri, record FROM records_strata WHERE uri = ?")
        .bind(id)
        .first<{ uri: string; record: string }>();

      if (!row) {
        return c.json({ error: "RecordNotFound" }, 404);
      }

      const rec = JSON.parse(row.record);
      const lexmin = rec.source?.uri;
      if (!lexmin) {
        return c.json({ error: "InvalidRecord" }, 400);
      }

      const island = await deriveIsland(db, lexmin);
      if (!island) {
        return c.json({ error: "IslandNotFound" }, 404);
      }

      const meta = await resolveVertexMeta(db, island.vertices);
      const analysis = rec.analysis || {};

      return c.json({
        island: {
          ...island,
          lexmin: island.vertices.slice().sort()[0],
          vertexMeta: Object.fromEntries(meta),
          summary: analysis.title || null,
          strata: {
            prose: analysis.synthesis || "",
            title: analysis.title || "",
            themes: analysis.themes || [],
            relationships: (analysis.connections || []).map((conn: any) => conn.description || ""),
            tensions: analysis.tensions || [],
            open_questions: analysis.openQuestions || [],
            synthesis: analysis.synthesis || "",
          },
        },
        recordUri: row.uri,
      });
    }

    // Stable ID — derive from lexmin by reverse-lookup
    // Find the strata record whose lexmin hashes to this ID
    const strataRows = await db
      .prepare("SELECT uri, record FROM records_strata")
      .all<{ uri: string; record: string }>();

    for (const row of strataRows.results || []) {
      try {
        const rec = JSON.parse(row.record);
        const lexmin = rec.source?.uri;
        if (!lexmin) continue;

        const lexminHash = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(lexmin));
        const candidateId = Array.from(new Uint8Array(lexminHash)).map(b => b.toString(16).padStart(2, "0")).join("").slice(0, 16);

        if (candidateId === id) {
          const island = await deriveIsland(db, lexmin);
          if (!island) continue;

          const meta = await resolveVertexMeta(db, island.vertices);
          const analysis = rec.analysis || {};

          return c.json({
            island: {
              ...island,
              lexmin: island.vertices.slice().sort()[0],
              vertexMeta: Object.fromEntries(meta),
              summary: analysis.title || null,
              strata: {
                prose: analysis.synthesis || "",
                title: analysis.title || "",
                themes: analysis.themes || [],
                relationships: (analysis.connections || []).map((conn: any) => conn.description || ""),
                tensions: analysis.tensions || [],
                open_questions: analysis.openQuestions || [],
                synthesis: analysis.synthesis || "",
              },
            },
            recordUri: row.uri,
          });
        }
      } catch {}
    }

    // No strata record — try deriving island by treating the ID as a lexmin seed
    // (for islands that haven't been analyzed yet)
    const island = await deriveIsland(db, id);
    if (!island) {
      return c.json({ error: "IslandNotFound" }, 404);
    }

    const meta = await resolveVertexMeta(db, island.vertices);
    return c.json({
      island: {
        ...island,
        lexmin: island.vertices.slice().sort()[0],
        vertexMeta: Object.fromEntries(meta),
        summary: null,
        strata: null,
      },
      recordUri: null,
    });
  });

  // ── List strata records (AT URI-based) ──────────────────────────

  app.get("/xrpc/org.latha.strata.listRecords", async (c) => {
    const rows = await db
      .prepare("SELECT uri, record FROM records_strata ORDER BY time_us DESC LIMIT 50")
      .all<{ uri: string; record: string }>();

    const records = (rows.results || []).map(r => {
      try {
        const rec = JSON.parse(r.record);
        return {
          uri: r.uri,
          source: rec.source?.uri || "",
          title: rec.analysis?.title || "",
          themes: rec.analysis?.themes || [],
          createdAt: rec.createdAt || "",
        };
      } catch {
        return null;
      }
    }).filter(Boolean);

    return c.json({ records });
  });

  // ── Strata record endpoint (AT URI-based) ──────────────────────

  app.get("/xrpc/org.latha.strata.getRecord", async (c) => {
    const uri = c.req.query("uri");
    if (!uri) {
      return c.json({ error: "MissingRequiredParameter", message: "uri is required" }, 400);
    }

    // Fetch the strata record from D1 (indexed by Contrail)
    const row = await db
      .prepare("SELECT record FROM records_strata WHERE uri = ?")
      .bind(uri)
      .first<{ record: string }>();

    if (!row) {
      return c.json({ error: "NotFound", message: "Strata record not found" }, 404);
    }

    let strataRecord: any;
    try {
      strataRecord = JSON.parse(row.record);
    } catch {
      return c.json({ error: "InvalidRecord" }, 500);
    }

    // Derive island from lexmin (source.uri)
    const lexmin = strataRecord.source?.uri;
    if (!lexmin) {
      return c.json({ error: "MissingLexmin", message: "Strata record has no source.uri" }, 400);
    }

    const island = await deriveIsland(db, lexmin);
    if (!island) {
      return c.json({ error: "IslandNotFound", message: "Could not derive island from lexmin" }, 404);
    }

    // Resolve vertex metadata
    const meta = await resolveVertexMeta(db, island.vertices);

    // Build the response in the same format as the island cache
    const analysis = strataRecord.analysis || {};
    const strataData = {
      prose: analysis.synthesis || "",
      title: analysis.title || "",
      themes: analysis.themes || [],
      relationships: (analysis.connections || []).map((c: any) => c.description || ""),
      tensions: analysis.tensions || [],
      open_questions: analysis.openQuestions || [],
      synthesis: analysis.synthesis || "",
    };

    return c.json({
      island: {
        ...island,
        vertexMeta: Object.fromEntries(meta),
        summary: analysis.title || null,
        strata: strataData,
      },
      record: strataRecord,
      recordUri: uri,
    });
  });

  // ── Container-backed xrpc methods ────────────────────────────────

  // Helper: call the strata container
  async function callContainer(path: string, method: string, body?: any): Promise<any> {
    const id = env.STRATA_CONTAINER.idFromName("strata");
    const stub = env.STRATA_CONTAINER.get(id);
    const url = new URL(path, "http://container");
    const init: RequestInit = { method };
    if (body) {
      init.body = JSON.stringify(body);
      init.headers = { "Content-Type": "application/json" };
    }
    const resp = await stub.fetch(new Request(url.toString(), init));
    return resp.json();
  }

  // Derive islands — POST, delegates to container
  // With seed: single island. Without: all islands.
  app.post("/xrpc/org.latha.strata.deriveIsland", async (c) => {
    const body = await c.req.json().catch(() => ({})) as { seed?: string };
    const seed = body.seed;

    // Load all connections from D1 for the container to traverse
    await ensureContrailReady(db);
    const rows = await db
      .prepare(
        `SELECT r.record, r.did, r.rkey, i.handle
         FROM records_connection r
         LEFT JOIN identities i ON r.did = i.did`,
      )
      .all<{ record: string; did: string; rkey: string; handle: string | null }>();

    const connections = (rows.results || []).map(r => {
      try {
        const value = JSON.parse(r.record);
        return {
          source: value.source,
          target: value.target,
          connectionType: value.connectionType || "relates",
          note: value.note || "",
          did: r.did,
          rkey: r.rkey,
        };
      } catch {
        return null;
      }
    }).filter(Boolean);

    try {
      const result = await callContainer("/deriveIsland", "POST", { connections, seed: seed || undefined });
      return c.json(result);
    } catch (e: any) {
      return c.json({ error: "ContainerError", message: e.message }, 500);
    }
  });

  // Run strata analysis — delegates to container
  app.post("/xrpc/org.latha.strata.analyze", async (c) => {
    const body = await c.req.json().catch(() => ({}));
    if (!body.island) {
      return c.json({ error: "MissingRequiredField", message: "island is required" }, 400);
    }

    try {
      const result = await callContainer("/analyze", "POST", body);
      return c.json(result);
    } catch (e: any) {
      return c.json({ error: "ContainerError", message: e.message }, 500);
    }
  });

  // ── R2 sync endpoints ───────────────────────────────────────────

  app.put("/api/sync/vault/:did/*", async (c) => {
    const did = c.req.param("did");
    const path = c.req.param("path");
    if (!did || !path) {
      return c.json({ error: "Missing path" }, 400);
    }

    const key = `${did}/${path}`;
    const body = await c.req.raw.arrayBuffer();
    await env.VAULT_BUCKET.put(key, body, {
      httpMetadata: { contentType: c.req.header("content-type") || "text/markdown" },
    });

    return c.json({ ok: true, key });
  });

  app.put("/api/sync/carry/:did/*", async (c) => {
    const did = c.req.param("did");
    const path = c.req.param("path");
    if (!did || !path) {
      return c.json({ error: "Missing path" }, 400);
    }

    const key = `${did}/${path}`;
    const body = await c.req.raw.arrayBuffer();
    await env.CARRY_BUCKET.put(key, body, {
      httpMetadata: { contentType: c.req.header("content-type") || "application/json" },
    });

    return c.json({ ok: true, key });
  });

  // ── Graph neighborhood query ────────────────────────────────────

  app.get("/xrpc/org.latha.strata.connection.getGraph", async (c) => {
    const uri = c.req.query("uri");
    if (!uri) {
      return c.json({ error: "MissingRequiredParameter", message: "uri is required" }, 400);
    }

    const depth = Math.min(parseInt(c.req.query("depth") || "2"), 3);
    const limit = Math.min(parseInt(c.req.query("limit") || "50"), 100);
    const types = c.req.query("types")?.split(",").map((t) => t.trim());

    // Reuse island detection for the subgraph
    const islands = await detectIslands(db);
    const island = islands.find(i => i.vertices.includes(uri));

    if (!island) {
      return c.json({ connections: [], resources: [], depth, uri });
    }

    // Convert to graph format
    const resources = island.vertices.map(v => ({
      uri: v,
      title: v,
      type: "unknown",
    }));

    return c.json({
      connections: island.edges,
      resources,
      depth,
      uri,
    });
  });

  // ── OAuth client metadata ──────────────────────────────────────

  app.get("/oauth-client-metadata.json", (c) => {
    const host = new URL(c.req.url).host;
    return c.json({
      client_id: `https://${host}/oauth-client-metadata.json`,
      client_name: "Stigmergic",
      client_uri: `https://${host}`,
      redirect_uris: [`https://${host}/`],
      scope: "atproto transition:generic",
      grant_types: ["authorization_code", "refresh_token"],
      response_types: ["code"],
      token_endpoint_auth_method: "none",
      application_type: "web",
      dpop_bound_access_tokens: true,
    });
  });

  // ── SPA fallback: serve landing page for client-side routes ──────
  for (const path of ["/island", "/strata", "/connect"]) {
    app.get(path, async (c) => {
      let islandsJson = "[]";
      try {
        await ensureContrailReady(db);
        const rows = await db
          .prepare("SELECT uri, record FROM records_strata ORDER BY time_us DESC LIMIT 50")
          .all<{ uri: string; record: string }>();
        const islands: any[] = [];
        for (const row of rows.results || []) {
          try {
            const rec = JSON.parse(row.record);
            const lexmin = rec.source?.uri;
            if (!lexmin) continue;
            const lexminHash = await crypto.subtle.digest("SHA-256", new TextEncoder().encode(lexmin));
            const id = Array.from(new Uint8Array(lexminHash)).map(b => b.toString(16).padStart(2, "0")).join("").slice(0, 16);
            islands.push({ id, lexmin, title: rec.analysis?.title || null, recordUri: row.uri });
          } catch {}
        }
        islandsJson = JSON.stringify(islands);
      } catch {}

      const page = LANDING_PAGE.replace(
        "</head>",
        `<script>window.__ISLANDS__=${islandsJson};</script></head>`,
      );
      return c.html(page);
    });
  }

  // ── All other routes pass through to contrail ──────────────────

  app.all("*", async (c) => {
    const response = await contrailWorker.fetch(
      c.req.raw,
      c.env as unknown as Record<string, unknown>,
    );
    return response;
  });

  return app;
}

// ─── Export ─────────────────────────────────────────────────────────

export { StrataContainer };

export default {
  fetch(request: Request, env: Env): Response | Promise<Response> {
    app ??= buildApp(env);
    return app.fetch(request, env);
  },
  async scheduled(event: ScheduledEvent, env: Env, ctx: ExecutionContext) {
    // Run Contrail indexing
    await contrailWorker.scheduled(
      event,
      env as unknown as Record<string, unknown>,
      ctx,
    );
  },
};