/**
 * Desktop-only surfaces that have no web equivalent in V1 (ticket #13, lot F1):
 * the native folder picker, OS view-windows and the main↔detached focused-project
 * channel, plus SSH/WSL remote. On the web client these must fail with a clear,
 * explicit error rather than reaching for Tauri (which is absent).
 *
 * The B0 inventory classified these as `desktop-only`; F1 does NOT implement them
 * for web. If/when the product wants an equivalent (e.g. a server-side folder
 * browser to replace `pickFolder`), it gets its own lot.
 */

import type {
  EmbeddedServerStatus,
  GatewayError,
  PluginAdmin,
  PluginCommandTask,
  PluginConfigDocument,
  PluginConfigDocumentWriteResult,
  PluginEventBatch,
  PluginEventSubscription,
  PluginInstallResult,
  PluginToolchainDiagnostic,
  PluginProjectStructure,
  PluginReview,
  PluginRuntimeContributionCatalog,
  PluginUninstallResult,
  PluginWorkspaceBinaryFile,
  PluginWorkspaceDirectoryListing,
  PluginWorkspaceStat,
  PluginWorkspaceTextFile,
  ServerExposurePreview,
  ServerExposureSettings,
  Unsubscribe,
} from "@/domain";
import type {
  DesktopServerGateway,
  FocusedProject,
  FocusedProjectGateway,
  PluginConfigDocumentReadInput,
  PluginConfigDocumentUpdateInput,
  PluginConfigGateway,
  PluginEventGateway,
  PluginEventPollInput,
  PluginEventSubscribeInput,
  PluginEventUnsubscribeInput,
  PluginGateway,
  PluginProjectStructureQuery,
  PluginRunCommandInput,
  PluginTaskGateway,
  PluginTaskStatusInput,
  PluginToolchainDiagnosticRequest,
  PluginToolchainGateway,
  PluginWorkspaceGateway,
  PluginWorkspacePathInput,
  PluginWorkspaceWriteBinaryInput,
  PluginWorkspaceWriteTextInput,
  RemoteGateway,
  ReviewPluginPackageInput,
  ViewWindowClosed,
  ViewWindowSnapshot,
  WindowGateway,
} from "@/ports";

/** Throws a stable, explicit "unsupported on web" {@link GatewayError}. */
export function unsupportedOnWeb(what: string): never {
  const err: GatewayError = {
    code: "UNSUPPORTED_ON_WEB",
    message: `${what} is not available in the web client (desktop-only).`,
  };
  throw err;
}

/** Web stub: OS view-windows are desktop-only (no `WebviewWindow` on the web). */
export class WebWindowGateway implements WindowGateway {
  openViewWindow(): Promise<void> {
    return unsupportedOnWeb("Detaching a panel into an OS window");
  }
  closeViewWindow(): Promise<void> {
    return unsupportedOnWeb("Closing a detached OS window");
  }
  listOpenViewWindows(): Promise<ViewWindowSnapshot[]> {
    // Best-effort by contract (callers treat rejection as "no reconciliation"),
    // but there are simply never detached OS windows on web → empty list.
    return Promise.resolve([]);
  }
  onViewWindowClosed(
    _handler: (event: ViewWindowClosed) => void,
  ): Promise<Unsubscribe> {
    // No OS windows ⇒ nothing ever fires; return a no-op unsubscribe.
    return Promise.resolve(() => {});
  }
}

/**
 * Web stub for the focused-project channel. With no detached windows on web the
 * channel has no cross-window consumer; F1 keeps it inert (no publish, no focus).
 * A future multi-tab web build could back this with `BroadcastChannel`.
 */
export class WebFocusedProjectGateway implements FocusedProjectGateway {
  setFocusedProject(_project: FocusedProject | null): Promise<void> {
    // No-op: nothing reads the channel on web V1.
    return Promise.resolve();
  }
  getFocusedProject(): Promise<FocusedProject | null> {
    return Promise.resolve(null);
  }
  onFocusedProjectChanged(
    _handler: (project: FocusedProject | null) => void,
  ): Promise<Unsubscribe> {
    return Promise.resolve(() => {});
  }
}

/** Web stub: SSH/WSL remote connection is desktop-only in V1. */
export class WebRemoteGateway implements RemoteGateway {
  connect(): Promise<void> {
    return unsupportedOnWeb("Remote (SSH/WSL) connection");
  }
}

/**
 * Web stub: the embedded server is desktop-only (ticket #68). A web client is
 * *served by* this very server, so letting it reconfigure or stop the server
 * would let a remote device saw off the branch it sits on. The desktop app owns
 * this surface; every call fails explicitly rather than reaching for Tauri.
 */
export class WebDesktopServerGateway implements DesktopServerGateway {
  // `async` on purpose: these must *reject* rather than throw synchronously, so
  // callers using `.then(ok, err)` (not just `await`) still see the failure.
  async getExposureSettings(): Promise<ServerExposureSettings> {
    return unsupportedOnWeb("Embedded server settings");
  }
  async saveExposureSettings(_settings: ServerExposureSettings): Promise<void> {
    return unsupportedOnWeb("Embedded server settings");
  }
  async previewExposure(
    _settings: ServerExposureSettings,
  ): Promise<ServerExposurePreview> {
    return unsupportedOnWeb("Embedded server settings");
  }
  async status(): Promise<EmbeddedServerStatus> {
    return unsupportedOnWeb("Embedded server status");
  }
  async start(): Promise<EmbeddedServerStatus> {
    return unsupportedOnWeb("Starting the embedded server");
  }
  async stop(): Promise<EmbeddedServerStatus> {
    return unsupportedOnWeb("Stopping the embedded server");
  }
  onStatusChanged(
    _handler: (status: EmbeddedServerStatus) => void,
  ): Promise<Unsubscribe> {
    // Never fires on web; a no-op unsubscribe keeps callers' teardown honest.
    return Promise.resolve(() => {});
  }
}

/**
 * Web stub: the plugin system (#43) installs/loads full-trust local ESM
 * bundles from the desktop filesystem — no server-side equivalent in V1. The
 * web client must not manage or load plugins on behalf of the desktop app.
 */
export class WebPluginGateway implements PluginGateway {
  async listPlugins(): Promise<PluginAdmin[]> {
    return unsupportedOnWeb("Plugin management");
  }
  async reviewPackage(_input: ReviewPluginPackageInput): Promise<PluginReview> {
    return unsupportedOnWeb("Plugin management");
  }
  async installFromArchive(_path: string): Promise<PluginInstallResult> {
    return unsupportedOnWeb("Plugin management");
  }
  async installFromDirectory(_path: string): Promise<PluginInstallResult> {
    return unsupportedOnWeb("Plugin management");
  }
  async setEnabled(_pluginId: string, _enabled: boolean): Promise<PluginAdmin> {
    return unsupportedOnWeb("Plugin management");
  }
  async uninstall(_pluginId: string): Promise<PluginUninstallResult> {
    return unsupportedOnWeb("Plugin management");
  }
  async listRuntimeContributions(): Promise<PluginRuntimeContributionCatalog> {
    // No plugin bundles are ever loaded on the web client — an empty catalog
    // lets the bootstrap loader run unconditionally without a transport check.
    return { plugins: [] };
  }
  async openPluginsFolder(_pluginId?: string): Promise<void> {
    return unsupportedOnWeb("Plugin management");
  }
}

/** Web stub: public plugin workspace services are only meaningful where plugins run. */
export class WebPluginWorkspaceGateway implements PluginWorkspaceGateway {
  async readText(_input: PluginWorkspacePathInput): Promise<PluginWorkspaceTextFile> {
    return unsupportedOnWeb("Plugin workspace access");
  }
  async readBinary(_input: PluginWorkspacePathInput): Promise<PluginWorkspaceBinaryFile> {
    return unsupportedOnWeb("Plugin workspace access");
  }
  async writeText(_input: PluginWorkspaceWriteTextInput): Promise<void> {
    return unsupportedOnWeb("Plugin workspace access");
  }
  async writeBinary(_input: PluginWorkspaceWriteBinaryInput): Promise<void> {
    return unsupportedOnWeb("Plugin workspace access");
  }
  async listDir(_input: PluginWorkspacePathInput): Promise<PluginWorkspaceDirectoryListing> {
    return unsupportedOnWeb("Plugin workspace access");
  }
  async stat(_input: PluginWorkspacePathInput): Promise<PluginWorkspaceStat> {
    return unsupportedOnWeb("Plugin workspace access");
  }
  async queryProjectStructure(
    _input: PluginProjectStructureQuery,
  ): Promise<PluginProjectStructure> {
    return unsupportedOnWeb("Plugin workspace access");
  }
}

/** Web stub: plugin command tasks are desktop-hosted in this runtime. */
export class WebPluginTaskGateway implements PluginTaskGateway {
  async runCommand(_input: PluginRunCommandInput): Promise<PluginCommandTask> {
    return unsupportedOnWeb("Plugin command tasks");
  }

  async getStatus(_input: PluginTaskStatusInput): Promise<PluginCommandTask | null> {
    return unsupportedOnWeb("Plugin command tasks");
  }
}

/** Web stub: plugin toolchain diagnostics run on the desktop host. */
export class WebPluginToolchainGateway implements PluginToolchainGateway {
  async diagnose(
    _input: PluginToolchainDiagnosticRequest,
  ): Promise<PluginToolchainDiagnostic> {
    return unsupportedOnWeb("Plugin toolchain diagnostics");
  }
}

/** Web stub: plugin public events are sourced from the desktop host. */
export class WebPluginEventGateway implements PluginEventGateway {
  async subscribe(_input: PluginEventSubscribeInput): Promise<PluginEventSubscription> {
    return unsupportedOnWeb("Plugin public events");
  }

  async poll(_input: PluginEventPollInput): Promise<PluginEventBatch> {
    return unsupportedOnWeb("Plugin public events");
  }

  async unsubscribe(_input: PluginEventUnsubscribeInput): Promise<PluginEventSubscription> {
    return unsupportedOnWeb("Plugin public events");
  }
}

/** Web stub: plugin config documents are read/written by the desktop host. */
export class WebPluginConfigGateway implements PluginConfigGateway {
  async readDocument(_input: PluginConfigDocumentReadInput): Promise<PluginConfigDocument> {
    return unsupportedOnWeb("Plugin structured config documents");
  }

  async updateDocument(
    _input: PluginConfigDocumentUpdateInput,
  ): Promise<PluginConfigDocumentWriteResult> {
    return unsupportedOnWeb("Plugin structured config documents");
  }
}