import { Elysia, t } from "elysia";
import { requireAuth } from "./auth";
import sql from "../db";
import { dispatch, knownProviderKinds, type ChannelRow } from "../notifications";

const ChannelBody = t.Object({
  name:    t.String({ minLength: 1, maxLength: 200 }),
  kind:    t.String({ description: "Provider kind, e.g. 'webhook'" }),
  config:  t.Any({ description: "Provider-specific config object" }),
  enabled: t.Optional(t.Boolean()),
});

function validateKind(kind: string): string | null {
  if (!knownProviderKinds().includes(kind)) {
    return `Unknown provider kind '${kind}'. Known: ${knownProviderKinds().join(", ")}`;
  }
  return null;
}

function validateWebhookConfig(config: any): string | null {
  if (!config || typeof config !== "object") return "config must be an object";
  if (typeof config.url !== "string" || !/^https?:\/\//.test(config.url)) {
    return "webhook config.url must be a http(s) URL";
  }
  return null;
}

function validateConfig(kind: string, config: any): string | null {
  if (kind === "webhook") return validateWebhookConfig(config);
  return null;
}

export const channels = new Elysia({ prefix: "/notifications/channels" })
  .use(requireAuth)

  .get("/", async ({ accountId }) => {
    return sql`
      SELECT id, name, kind, config, enabled, created_at
      FROM notification_channels
      WHERE account_id = ${accountId}
      ORDER BY created_at DESC
    `;
  }, { detail: { summary: "List notification channels", tags: ["notifications"] } })

  .post("/", async ({ accountId, body, set }) => {
    const kindErr = validateKind(body.kind);
    if (kindErr) { set.status = 400; return { error: kindErr }; }
    const cfgErr = validateConfig(body.kind, body.config);
    if (cfgErr) { set.status = 400; return { error: cfgErr }; }

    const [row] = await sql`
      INSERT INTO notification_channels (account_id, name, kind, config, enabled)
      VALUES (${accountId}, ${body.name}, ${body.kind}, ${sql.json(body.config)}, ${body.enabled ?? true})
      RETURNING id, name, kind, config, enabled, created_at
    `;
    return row;
  }, { body: ChannelBody, detail: { summary: "Create notification channel", tags: ["notifications"] } })

  .patch("/:id", async ({ accountId, params, body, set }) => {
    if (body.kind != null) {
      const kindErr = validateKind(body.kind);
      if (kindErr) { set.status = 400; return { error: kindErr }; }
    }
    if (body.config != null) {
      const kind = body.kind ?? (await sql`SELECT kind FROM notification_channels WHERE id = ${params.id} AND account_id = ${accountId}`)[0]?.kind;
      if (kind) {
        const cfgErr = validateConfig(kind, body.config);
        if (cfgErr) { set.status = 400; return { error: cfgErr }; }
      }
    }

    const [row] = await sql`
      UPDATE notification_channels SET
        name    = COALESCE(${body.name ?? null},                                       name),
        kind    = COALESCE(${body.kind ?? null},                                       kind),
        config  = COALESCE(${body.config != null ? sql.json(body.config) : null},      config),
        enabled = COALESCE(${body.enabled ?? null},                                    enabled)
      WHERE id = ${params.id} AND account_id = ${accountId}
      RETURNING id, name, kind, config, enabled, created_at
    `;
    if (!row) { set.status = 404; return { error: "Not found" }; }
    return row;
  }, { body: t.Partial(ChannelBody), detail: { summary: "Update notification channel", tags: ["notifications"] } })

  .delete("/:id", async ({ accountId, params, set }) => {
    const [row] = await sql`
      DELETE FROM notification_channels
      WHERE id = ${params.id} AND account_id = ${accountId}
      RETURNING id
    `;
    if (!row) { set.status = 404; return { error: "Not found" }; }
    return { deleted: true };
  }, { detail: { summary: "Delete notification channel", tags: ["notifications"] } })

  .post("/:id/test", async ({ accountId, params, set }) => {
    const [row] = await sql<ChannelRow[]>`
      SELECT id, account_id, name, kind, config, enabled
      FROM notification_channels
      WHERE id = ${params.id} AND account_id = ${accountId}
    `;
    if (!row) { set.status = 404; return { error: "Not found" }; }
    try {
      await dispatch(row, {
        kind:    "test",
        monitor: { id: "test", name: "Test event", url: "https://example.com", region: "" },
      });
      return { ok: true };
    } catch (e: any) {
      set.status = 502;
      return { error: e?.message || String(e) };
    }
  }, { detail: { summary: "Send a test event to a channel", tags: ["notifications"] } });