import * as Effect from "effect/Effect";
import * as Binding from "../../Binding.ts";
import type { PolicyStatement } from "../IAM/Policy.ts";
import { isBindingHost } from "../Lambda/Function.ts";
import type { Service } from "./Service.ts";

/**
 * Shared scaffolding for AWS Cloud Map HTTP bindings.
 *
 * NOT exported from `index.ts` — every `{Op}Http.ts` in this service is a
 * thin `Layer.effect(Cap, make…HttpBinding({ … }))` over one of the three
 * builders below. Everything except the operation, the IAM action list, and
 * the injected identifier is boilerplate.
 */

/**
 * Build the impl Effect for a service-scoped control/data operation. The
 * runtime callable injects the bound {@link Service}'s id as the request's
 * `ServiceId`; the deploy-time half grants `actions` on the service ARN
 * plus any `extraStatements` (e.g. the Route 53 record management Cloud Map
 * performs on the caller's behalf for DNS services).
 */
export const makeCloudMapServiceHttpBinding = <
  I extends { ServiceId: string },
  A,
  E,
  R,
>(options: {
  /** Fully-qualified binding tag, e.g. `AWS.CloudMap.GetInstance`. */
  tag: string;
  /** The distilled operation; `ServiceId` is injected from the service. */
  operation: Effect.Effect<(input: I) => Effect.Effect<A, E>, never, R>;
  /** IAM actions granted on the service ARN. */
  actions: readonly string[];
  /** Additional statements granted alongside the service-scoped one. */
  extraStatements?: readonly PolicyStatement[];
}) =>
  Effect.gen(function* () {
    const op = yield* options.operation;

    return Effect.fn(function* (service: Service) {
      const ServiceId = yield* service.serviceId;
      if (!globalThis.__ALCHEMY_RUNTIME__) {
        const host = yield* Binding.Host;
        if (isBindingHost(host)) {
          yield* host.bind`Allow(${host}, ${options.tag}(${service}))`({
            policyStatements: [
              {
                Effect: "Allow",
                Action: [...options.actions],
                Resource: [service.serviceArn],
              },
              ...(options.extraStatements ?? []),
            ],
          });
        }
      }
      return Effect.fn(`${options.tag}(${service.LogicalId})`)(function* (
        request?: Omit<I, "ServiceId">,
      ) {
        return yield* op({
          ...request,
          ServiceId: yield* ServiceId,
        } as I);
      });
    });
  });

/**
 * Build the impl Effect for a discovery data-plane operation
 * (`DiscoverInstances` / `DiscoverInstancesRevision`). The runtime callable
 * injects the bound {@link Service}'s namespace and service names; the
 * deploy-time half grants `actions` on `*` — the discovery data-plane
 * actions do not support resource-level IAM permissions.
 */
export const makeCloudMapDiscoveryHttpBinding = <
  I extends { NamespaceName: string; ServiceName: string },
  A,
  E,
  R,
>(options: {
  /** Fully-qualified binding tag, e.g. `AWS.CloudMap.DiscoverInstances`. */
  tag: string;
  /** The distilled operation; the names are injected from the service. */
  operation: Effect.Effect<(input: I) => Effect.Effect<A, E>, never, R>;
  /** IAM actions granted on `*` (no resource-level scoping). */
  actions: readonly string[];
}) =>
  Effect.gen(function* () {
    const op = yield* options.operation;

    return Effect.fn(function* (service: Service) {
      const NamespaceName = yield* service.namespaceName;
      const ServiceName = yield* service.serviceName;
      if (!globalThis.__ALCHEMY_RUNTIME__) {
        const host = yield* Binding.Host;
        if (isBindingHost(host)) {
          yield* host.bind`Allow(${host}, ${options.tag}(${service}))`({
            policyStatements: [
              {
                Effect: "Allow",
                Action: [...options.actions],
                Resource: ["*"],
              },
            ],
          });
        }
      }
      return Effect.fn(`${options.tag}(${service.LogicalId})`)(function* (
        request?: Omit<I, "NamespaceName" | "ServiceName">,
      ) {
        return yield* op({
          ...request,
          NamespaceName: yield* NamespaceName,
          ServiceName: yield* ServiceName,
        } as I);
      });
    });
  });

/**
 * Build the impl Effect for an account-level operation (`GetOperation`).
 * The deploy-time half grants `actions` on `*` — these actions do not
 * support resource-level IAM permissions.
 */
export const makeCloudMapAccountHttpBinding = <I, A, E, R>(options: {
  /** Fully-qualified binding tag, e.g. `AWS.CloudMap.GetOperation`. */
  tag: string;
  /** The distilled operation, invoked with the caller's request as-is. */
  operation: Effect.Effect<(input: I) => Effect.Effect<A, E>, never, R>;
  /** IAM actions granted on `*`. */
  actions: readonly string[];
}) =>
  Effect.gen(function* () {
    const op = yield* options.operation;

    return Effect.fn(function* () {
      if (!globalThis.__ALCHEMY_RUNTIME__) {
        const host = yield* Binding.Host;
        if (isBindingHost(host)) {
          yield* host.bind`Allow(${host}, ${options.tag}())`({
            policyStatements: [
              {
                Effect: "Allow",
                Action: [...options.actions],
                Resource: ["*"],
              },
            ],
          });
        }
      }
      return Effect.fn(options.tag)(function* (request?: I) {
        return yield* op((request ?? {}) as I);
      });
    });
  });