/**
 * OpenCodeDriver — `ProviderDriver` for the OpenCode runtime.
 *
 * Mirrors the Codex / Claude drivers: a plain value whose `create()`
 * bundles `snapshot` / `adapter` / `textGeneration` closures over the
 * per-instance `OpenCodeSettings`.
 *
 * Two instances with different `serverUrl`s therefore talk to independent
 * OpenCode servers; when no `serverUrl` is set, the adapter + text-generation
 * shares spin up their own scoped child processes, and those child
 * processes are released when the registry scope closes.
 *
 * @module provider/Drivers/OpenCodeDriver
 */
import { OpenCodeSettings, ProviderDriverKind, type ServerProvider } from "@t3tools/contracts";
import { Duration, Effect, FileSystem, Path, Schema, Stream } from "effect";
import { ChildProcessSpawner } from "effect/unstable/process";

import { makeOpenCodeTextGeneration } from "../../textGeneration/OpenCodeTextGeneration.ts";
import { ServerConfig } from "../../config.ts";
import { ProviderDriverError } from "../Errors.ts";
import { makeOpenCodeAdapter } from "../Layers/OpenCodeAdapter.ts";
import {
  checkOpenCodeProviderStatus,
  makePendingOpenCodeProvider,
} from "../Layers/OpenCodeProvider.ts";
import { ProviderEventLoggers } from "../Layers/ProviderEventLoggers.ts";
import { makeManagedServerProvider } from "../makeManagedServerProvider.ts";
import { OpenCodeRuntime } from "../opencodeRuntime.ts";
import {
  defaultProviderContinuationIdentity,
  type ProviderDriver,
  type ProviderInstance,
} from "../ProviderDriver.ts";
import type { ServerProviderDraft } from "../providerSnapshot.ts";
import { mergeProviderInstanceEnvironment } from "../ProviderInstanceEnvironment.ts";

const DRIVER_KIND = ProviderDriverKind.make("opencode");
const SNAPSHOT_REFRESH_INTERVAL = Duration.minutes(5);

export type OpenCodeDriverEnv =
  | ChildProcessSpawner.ChildProcessSpawner
  | FileSystem.FileSystem
  | OpenCodeRuntime
  | Path.Path
  | ProviderEventLoggers
  | ServerConfig;

const withInstanceIdentity =
  (input: {
    readonly instanceId: ProviderInstance["instanceId"];
    readonly displayName: string | undefined;
    readonly accentColor: string | undefined;
    readonly continuationGroupKey: string;
  }) =>
  (snapshot: ServerProviderDraft): ServerProvider => ({
    ...snapshot,
    instanceId: input.instanceId,
    driver: DRIVER_KIND,
    ...(input.displayName ? { displayName: input.displayName } : {}),
    ...(input.accentColor ? { accentColor: input.accentColor } : {}),
    continuation: { groupKey: input.continuationGroupKey },
  });

export const OpenCodeDriver: ProviderDriver<OpenCodeSettings, OpenCodeDriverEnv> = {
  driverKind: DRIVER_KIND,
  metadata: {
    displayName: "OpenCode",
    supportsMultipleInstances: true,
  },
  configSchema: OpenCodeSettings,
  defaultConfig: (): OpenCodeSettings => Schema.decodeSync(OpenCodeSettings)({}),
  create: ({ instanceId, displayName, accentColor, environment, enabled, config }) =>
    Effect.gen(function* () {
      const openCodeRuntime = yield* OpenCodeRuntime;
      const serverConfig = yield* ServerConfig;
      const eventLoggers = yield* ProviderEventLoggers;
      const processEnv = mergeProviderInstanceEnvironment(environment);
      const continuationIdentity = defaultProviderContinuationIdentity({
        driverKind: DRIVER_KIND,
        instanceId,
      });
      const stampIdentity = withInstanceIdentity({
        instanceId,
        displayName,
        accentColor,
        continuationGroupKey: continuationIdentity.continuationKey,
      });
      const effectiveConfig = { ...config, enabled } satisfies OpenCodeSettings;

      const adapter = yield* makeOpenCodeAdapter(effectiveConfig, {
        instanceId,
        environment: processEnv,
        ...(eventLoggers.native ? { nativeEventLogger: eventLoggers.native } : {}),
      });
      const textGeneration = yield* makeOpenCodeTextGeneration(effectiveConfig, processEnv);

      const checkProvider = checkOpenCodeProviderStatus(
        effectiveConfig,
        serverConfig.cwd,
        processEnv,
      ).pipe(Effect.map(stampIdentity), Effect.provideService(OpenCodeRuntime, openCodeRuntime));

      const snapshot = yield* makeManagedServerProvider<OpenCodeSettings>({
        getSettings: Effect.succeed(effectiveConfig),
        streamSettings: Stream.never,
        haveSettingsChanged: () => false,
        initialSnapshot: (settings) => stampIdentity(makePendingOpenCodeProvider(settings)),
        checkProvider,
        refreshInterval: SNAPSHOT_REFRESH_INTERVAL,
      }).pipe(
        Effect.mapError(
          (cause) =>
            new ProviderDriverError({
              driver: DRIVER_KIND,
              instanceId,
              detail: `Failed to build OpenCode snapshot: ${cause.message ?? String(cause)}`,
              cause,
            }),
        ),
      );

      return {
        instanceId,
        driverKind: DRIVER_KIND,
        continuationIdentity,
        displayName,
        accentColor,
        enabled,
        snapshot,
        adapter,
        textGeneration,
      } satisfies ProviderInstance;
    }),
};