import * as keyspaces from "@distilled.cloud/aws/keyspaces";
import * as Effect from "effect/Effect";
import * as Layer from "effect/Layer";
import * as Binding from "../../Binding.ts";
import * as Output from "../../Output.ts";
import { isBindingHost } from "../Lambda/Function.ts";
import type { Keyspace } from "./Keyspace.ts";
import { RestoreTable, type RestoreTableRequest } from "./RestoreTable.ts";
import type { Table } from "./Table.ts";

/**
 * HTTP implementation of {@link RestoreTable}: grants `cassandra:Select` on
 * the source table plus `cassandra:Restore` (and the `Create`/`TagResource`
 * actions the restore performs) on the target keyspace and its tables, and
 * calls the Keyspaces HTTP API with the function's IAM credentials.
 */
export const RestoreTableHttp = Layer.effect(
  RestoreTable,
  Effect.gen(function* () {
    const restoreTable = yield* keyspaces.restoreTable;

    return Effect.fn(function* <From extends Table, To extends Keyspace>(
      source: From,
      targetKeyspace: To,
    ) {
      const SourceKeyspaceName = yield* source.keyspaceName;
      const SourceTableName = yield* source.tableName;
      const TargetKeyspaceName = yield* targetKeyspace.keyspaceName;
      if (!globalThis.__ALCHEMY_RUNTIME__) {
        const host = yield* Binding.Host;
        if (isBindingHost(host)) {
          yield* host.bind`Allow(${host}, AWS.Keyspaces.RestoreTable(${source}, ${targetKeyspace}))`(
            {
              policyStatements: [
                {
                  Effect: "Allow",
                  Action: ["cassandra:Select"],
                  Resource: [source.tableArn],
                },
                {
                  // The keyspace ARN ends with a trailing slash
                  // (`.../keyspace/name/`), so its tables match `table/*`.
                  Effect: "Allow",
                  Action: [
                    "cassandra:Restore",
                    "cassandra:Create",
                    "cassandra:TagResource",
                  ],
                  Resource: [
                    targetKeyspace.keyspaceArn,
                    Output.interpolate`${targetKeyspace.keyspaceArn}table/*`,
                  ],
                },
              ],
            },
          );
        }
      }
      return Effect.fn(`AWS.Keyspaces.RestoreTable(${source.LogicalId})`)(
        function* (request: RestoreTableRequest) {
          const sourceKeyspaceName = yield* SourceKeyspaceName;
          const sourceTableName = yield* SourceTableName;
          const targetKeyspaceName = yield* TargetKeyspaceName;
          return yield* restoreTable({
            ...request,
            sourceKeyspaceName,
            sourceTableName,
            targetKeyspaceName,
          });
        },
      );
    });
  }),
);