import * as autoscaling from "@distilled.cloud/aws/auto-scaling";
import * as Effect from "effect/Effect";
import * as Layer from "effect/Layer";
import * as Binding from "../../Binding.ts";
import { isInstance } from "../EC2/Instance.ts";
import { isBindingHost } from "../Lambda/Function.ts";
import type { AutoScalingGroup } from "./AutoScalingGroup.ts";
import {
  InstanceRefresh,
  type CancelInstanceRefreshRequest,
  type DescribeInstanceRefreshesRequest,
  type StartInstanceRefreshRequest,
} from "./InstanceRefresh.ts";

// Bespoke (not the shared scaffold): a multi-operation client over the four
// instance refresh operations behind one two-statement IAM grant (the write
// actions are group-scoped, Describe* only supports `*`).
export const InstanceRefreshHttp = Layer.effect(
  InstanceRefresh,
  Effect.gen(function* () {
    const start = yield* autoscaling.startInstanceRefresh;
    const cancel = yield* autoscaling.cancelInstanceRefresh;
    const rollback = yield* autoscaling.rollbackInstanceRefresh;
    const describe = yield* autoscaling.describeInstanceRefreshes;

    return Effect.fn(function* (group: AutoScalingGroup) {
      const AutoScalingGroupName = yield* group.autoScalingGroupName;
      if (!globalThis.__ALCHEMY_RUNTIME__) {
        const host = yield* Binding.Host;
        if (isBindingHost(host) || isInstance(host)) {
          yield* host.bind`Allow(${host}, AWS.AutoScaling.InstanceRefresh(${group}))`(
            {
              policyStatements: [
                {
                  Effect: "Allow",
                  Action: [
                    "autoscaling:StartInstanceRefresh",
                    "autoscaling:CancelInstanceRefresh",
                    "autoscaling:RollbackInstanceRefresh",
                  ],
                  Resource: [group.autoScalingGroupArn],
                },
                {
                  Effect: "Allow",
                  Action: ["autoscaling:DescribeInstanceRefreshes"],
                  Resource: ["*"],
                },
              ],
            },
          );
        }
      }
      return {
        start: Effect.fn(
          `AWS.AutoScaling.StartInstanceRefresh(${group.LogicalId})`,
        )(function* (request?: StartInstanceRefreshRequest) {
          return yield* start({
            ...request,
            AutoScalingGroupName: yield* AutoScalingGroupName,
          });
        }),
        cancel: Effect.fn(
          `AWS.AutoScaling.CancelInstanceRefresh(${group.LogicalId})`,
        )(function* (request?: CancelInstanceRefreshRequest) {
          return yield* cancel({
            ...request,
            AutoScalingGroupName: yield* AutoScalingGroupName,
          });
        }),
        rollback: Effect.fn(
          `AWS.AutoScaling.RollbackInstanceRefresh(${group.LogicalId})`,
        )(function* () {
          return yield* rollback({
            AutoScalingGroupName: yield* AutoScalingGroupName,
          });
        }),
        describe: Effect.fn(
          `AWS.AutoScaling.DescribeInstanceRefreshes(${group.LogicalId})`,
        )(function* (request?: DescribeInstanceRefreshesRequest) {
          return yield* describe({
            ...request,
            AutoScalingGroupName: yield* AutoScalingGroupName,
          });
        }),
      };
    });
  }),
);