feat: Implement Plugin Marketplace Manager and Client

- Added PluginMarketplaceManager to coordinate marketplace reads and manage installed plugins.
- Introduced PluginMarketplaceClient for fetching marketplace metadata.
- Implemented storage management for installed plugins using MemoryStorage.
- Added methods for installing, uninstalling, and enabling/disabling plugins.
- Created type definitions for PluginMarketplaceManager options and installed plugin records.
- Added support for fetching full marketplace catalog and individual plugin metadata.
- Included error handling for fetch operations and validation of plugin data.
- Updated index.browser.ts to export new modules and types.

dist/PluginMarketplaceClient.d.ts

@@ -0,0 +1,53 @@
+import type { PluginIndex, PluginMetadata } from './types.js';
+/**
+ * Minimal response shape required by marketplace client.
+ */
+export interface PluginMarketplaceResponse {
+    ok: boolean;
+    status: number;
+    json(): Promise<unknown>;
+}
+/**
+ * Fetch function used by marketplace client.
+ */
+export type PluginMarketplaceFetch = (input: string, init?: Record<string, unknown>) => Promise<PluginMarketplaceResponse>;
+/**
+ * Construction options for {@link PluginMarketplaceClient}.
+ */
+export interface PluginMarketplaceClientOptions {
+    /** URL of marketplace index JSON file. */
+    indexUrl: string;
+    /** Base URL used to resolve `${pluginId}.json` metadata files. */
+    baseUrl: string;
+    /** Optional fetch implementation. Falls back to global `fetch`. */
+    fetchFn?: PluginMarketplaceFetch;
+}
+/**
+ * Host-agnostic client for reading marketplace metadata.
+ */
+export declare class PluginMarketplaceClient {
+    private readonly indexUrl;
+    private readonly baseUrl;
+    private readonly fetchFn?;
+    constructor(options: PluginMarketplaceClientOptions);
+    /**
+     * Fetches and validates marketplace index.
+     */
+    fetchIndex(): Promise<PluginIndex>;
+    /**
+     * Fetches and validates single plugin metadata entry.
+     *
+     * @param pluginId - Identifier referenced by marketplace index.
+     */
+    fetchPlugin(pluginId: string): Promise<PluginMetadata>;
+    /**
+     * Fetches full marketplace catalog.
+     *
+     * Entries that fail fetch or validation get skipped so host can still render
+     * rest of catalog.
+     */
+    fetchPlugins(): Promise<PluginMetadata[]>;
+    private buildMetadataUrl;
+    private getFetchFn;
+}
+//# sourceMappingURL=PluginMarketplaceClient.d.ts.map

dist/PluginMarketplaceClient.d.ts.map

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dist/PluginMarketplaceClient.js

@@ -0,0 +1,94 @@
+/**
+ * Host-agnostic client for reading marketplace metadata.
+ */
+export class PluginMarketplaceClient {
+    constructor(options) {
+        this.indexUrl = options.indexUrl;
+        this.baseUrl = options.baseUrl;
+        this.fetchFn = options.fetchFn;
+    }
+    /**
+     * Fetches and validates marketplace index.
+     */
+    async fetchIndex() {
+        const response = await this.getFetchFn()(this.indexUrl);
+        if (!response.ok) {
+            throw new Error(`Failed to fetch plugin index: HTTP ${response.status}`);
+        }
+        return normalizePluginIndex(await response.json());
+    }
+    /**
+     * Fetches and validates single plugin metadata entry.
+     *
+     * @param pluginId - Identifier referenced by marketplace index.
+     */
+    async fetchPlugin(pluginId) {
+        const response = await this.getFetchFn()(this.buildMetadataUrl(pluginId));
+        if (!response.ok) {
+            throw new Error(`Failed to fetch plugin ${pluginId}: HTTP ${response.status}`);
+        }
+        return normalizePluginMetadata(await response.json(), pluginId);
+    }
+    /**
+     * Fetches full marketplace catalog.
+     *
+     * Entries that fail fetch or validation get skipped so host can still render
+     * rest of catalog.
+     */
+    async fetchPlugins() {
+        const index = await this.fetchIndex();
+        const results = await Promise.allSettled(index.plugins.map((pluginId) => this.fetchPlugin(pluginId)));
+        return results.flatMap((result) => (result.status === 'fulfilled' ? [result.value] : []));
+    }
+    buildMetadataUrl(pluginId) {
+        const trimmedBaseUrl = this.baseUrl.endsWith('/') ? this.baseUrl : `${this.baseUrl}/`;
+        return `${trimmedBaseUrl}${pluginId}.json`;
+    }
+    getFetchFn() {
+        if (this.fetchFn) {
+            return this.fetchFn;
+        }
+        if (typeof fetch !== 'function') {
+            throw new Error('No fetch implementation available for PluginMarketplaceClient');
+        }
+        return fetch;
+    }
+}
+function normalizePluginIndex(value) {
+    const record = asRecord(value, 'Plugin index payload must be object');
+    return {
+        version: asString(record.version),
+        updatedAt: asString(record.updatedAt),
+        plugins: Array.isArray(record.plugins)
+            ? record.plugins.filter((entry) => typeof entry === 'string')
+            : [],
+    };
+}
+function normalizePluginMetadata(value, fallbackId) {
+    const record = asRecord(value, `Plugin metadata for ${fallbackId} must be object`);
+    return {
+        id: asString(record.id) || fallbackId,
+        name: asString(record.name),
+        version: asString(record.version),
+        description: asString(record.description),
+        author: asString(record.author),
+        repository: asString(record.repository),
+        thumbnail: asString(record.thumbnail),
+        downloadUrl: asString(record.downloadUrl),
+        homepage: asString(record.homepage),
+        tags: Array.isArray(record.tags)
+            ? record.tags.filter((entry) => typeof entry === 'string')
+            : [],
+        addedDate: asString(record.addedDate),
+    };
+}
+function asRecord(value, message) {
+    if (!value || typeof value !== 'object' || Array.isArray(value)) {
+        throw new Error(message);
+    }
+    return value;
+}
+function asString(value) {
+    return typeof value === 'string' ? value : '';
+}
+//# sourceMappingURL=PluginMarketplaceClient.js.map

dist/PluginMarketplaceClient.js.map

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dist/PluginMarketplaceManager.d.ts

@@ -0,0 +1,88 @@
+import { type IPluginStorage } from './interfaces.js';
+import type { PluginRegistry } from './PluginRegistry.js';
+import type { InstalledPlugin, PluginMetadata } from './types.js';
+import { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+/**
+ * Host-visible installed-plugin metadata.
+ *
+ * Hosts may only know filesystem facts such as `id`, `name`, or `installedDate`.
+ * Stored marketplace metadata fills remaining fields.
+ */
+export type PluginMarketplaceInstalledRecord = Partial<InstalledPlugin> & Pick<InstalledPlugin, 'id'>;
+/**
+ * Host callbacks used by {@link PluginMarketplaceManager}.
+ */
+export interface PluginMarketplaceHostAdapter {
+    /**
+     * Returns host-known installed plugins.
+     */
+    listInstalledPlugins?(): Promise<PluginMarketplaceInstalledRecord[]>;
+    /**
+     * Performs host-specific install side effects.
+     */
+    installPlugin?(plugin: PluginMetadata): Promise<void>;
+    /**
+     * Performs host-specific uninstall side effects.
+     */
+    uninstallPlugin?(pluginId: string): Promise<void>;
+}
+/**
+ * Construction options for {@link PluginMarketplaceManager}.
+ */
+export interface PluginMarketplaceManagerOptions {
+    /** Shared marketplace client used to query remote metadata. */
+    client: PluginMarketplaceClient;
+    /** Optional persistent storage for installed-plugin state. */
+    storage?: IPluginStorage;
+    /** Optional host adapter for install and discovery side effects. */
+    host?: PluginMarketplaceHostAdapter;
+    /** Optional registry used when disabling or uninstalling loaded plugins. */
+    registry?: PluginRegistry;
+    /** Optional override for installed-plugin storage key. */
+    installedPluginsStorageKey?: string;
+}
+/**
+ * Coordinates marketplace reads with host-specific install and enable state.
+ */
+export declare class PluginMarketplaceManager {
+    private readonly client;
+    private readonly storage;
+    private readonly host?;
+    private readonly registry?;
+    private readonly installedPluginsStorageKey;
+    constructor(options: PluginMarketplaceManagerOptions);
+    /**
+     * Fetches full marketplace catalog.
+     */
+    fetchMarketplacePlugins(): Promise<PluginMetadata[]>;
+    /**
+     * Lists installed plugins merged with persisted enabled state.
+     */
+    listInstalledPlugins(): Promise<InstalledPlugin[]>;
+    /**
+     * Lists installed plugins currently enabled.
+     */
+    listEnabledPlugins(): Promise<InstalledPlugin[]>;
+    /**
+     * Returns whether plugin is recorded as installed.
+     */
+    isPluginInstalled(pluginId: string): Promise<boolean>;
+    /**
+     * Installs marketplace plugin via host adapter and persists state.
+     */
+    installPlugin(plugin: PluginMetadata): Promise<InstalledPlugin>;
+    /**
+     * Removes plugin from host and clears persisted install state.
+     */
+    uninstallPlugin(pluginId: string): Promise<void>;
+    /**
+     * Enables or disables installed plugin.
+     *
+     * Disabling triggers `registry.unregisterPlugin` when registry exists.
+     * Enabling only updates persisted state; host controls actual load timing.
+     */
+    setPluginEnabled(pluginId: string, enabled: boolean): Promise<InstalledPlugin | null>;
+    private readStoredInstalledPlugins;
+    private writeStoredInstalledPlugins;
+}
+//# sourceMappingURL=PluginMarketplaceManager.d.ts.map

dist/PluginMarketplaceManager.d.ts.map

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dist/PluginMarketplaceManager.js

@@ -0,0 +1,169 @@
+import { MemoryStorage } from './interfaces.js';
+const DEFAULT_INSTALLED_PLUGINS_STORAGE_KEY = 'plugin-manager:installed-plugins';
+/**
+ * Coordinates marketplace reads with host-specific install and enable state.
+ */
+export class PluginMarketplaceManager {
+    constructor(options) {
+        this.client = options.client;
+        this.storage = options.storage ?? new MemoryStorage();
+        this.host = options.host;
+        this.registry = options.registry;
+        this.installedPluginsStorageKey =
+            options.installedPluginsStorageKey ?? DEFAULT_INSTALLED_PLUGINS_STORAGE_KEY;
+    }
+    /**
+     * Fetches full marketplace catalog.
+     */
+    async fetchMarketplacePlugins() {
+        return this.client.fetchPlugins();
+    }
+    /**
+     * Lists installed plugins merged with persisted enabled state.
+     */
+    async listInstalledPlugins() {
+        const storedPlugins = this.readStoredInstalledPlugins();
+        if (!this.host?.listInstalledPlugins) {
+            return storedPlugins;
+        }
+        const hostPlugins = await this.host.listInstalledPlugins();
+        const mergedPlugins = mergeInstalledPlugins(hostPlugins, storedPlugins);
+        this.writeStoredInstalledPlugins(mergedPlugins);
+        return mergedPlugins;
+    }
+    /**
+     * Lists installed plugins currently enabled.
+     */
+    async listEnabledPlugins() {
+        return (await this.listInstalledPlugins()).filter((plugin) => plugin.enabled);
+    }
+    /**
+     * Returns whether plugin is recorded as installed.
+     */
+    async isPluginInstalled(pluginId) {
+        return (await this.listInstalledPlugins()).some((plugin) => plugin.id === pluginId);
+    }
+    /**
+     * Installs marketplace plugin via host adapter and persists state.
+     */
+    async installPlugin(plugin) {
+        await this.host?.installPlugin?.(plugin);
+        const installedPlugin = {
+            ...plugin,
+            installedDate: new Date().toISOString(),
+            enabled: true,
+        };
+        const updatedPlugins = upsertInstalledPlugin(this.readStoredInstalledPlugins(), installedPlugin);
+        this.writeStoredInstalledPlugins(updatedPlugins);
+        return updatedPlugins.find((entry) => entry.id === plugin.id) ?? installedPlugin;
+    }
+    /**
+     * Removes plugin from host and clears persisted install state.
+     */
+    async uninstallPlugin(pluginId) {
+        if (this.registry) {
+            await this.registry.unregisterPlugin(pluginId);
+        }
+        await this.host?.uninstallPlugin?.(pluginId);
+        this.writeStoredInstalledPlugins(this.readStoredInstalledPlugins().filter((plugin) => plugin.id !== pluginId));
+    }
+    /**
+     * Enables or disables installed plugin.
+     *
+     * Disabling triggers `registry.unregisterPlugin` when registry exists.
+     * Enabling only updates persisted state; host controls actual load timing.
+     */
+    async setPluginEnabled(pluginId, enabled) {
+        if (!enabled && this.registry) {
+            await this.registry.unregisterPlugin(pluginId);
+        }
+        const installedPlugins = await this.listInstalledPlugins();
+        const targetPlugin = installedPlugins.find((plugin) => plugin.id === pluginId);
+        if (!targetPlugin) {
+            return null;
+        }
+        const updatedPlugin = { ...targetPlugin, enabled };
+        this.writeStoredInstalledPlugins(upsertInstalledPlugin(installedPlugins, updatedPlugin));
+        return updatedPlugin;
+    }
+    readStoredInstalledPlugins() {
+        const rawValue = this.storage.getItem(this.installedPluginsStorageKey);
+        if (!rawValue) {
+            return [];
+        }
+        try {
+            const parsedValue = JSON.parse(rawValue);
+            if (!Array.isArray(parsedValue)) {
+                return [];
+            }
+            return parsedValue
+                .map((entry) => normalizeInstalledPlugin(entry))
+                .filter((entry) => entry !== null);
+        }
+        catch {
+            return [];
+        }
+    }
+    writeStoredInstalledPlugins(plugins) {
+        this.storage.setItem(this.installedPluginsStorageKey, JSON.stringify(plugins));
+    }
+}
+function mergeInstalledPlugins(hostPlugins, storedPlugins) {
+    const storedPluginsById = new Map(storedPlugins.map((plugin) => [plugin.id, plugin]));
+    const discoveredAt = new Date().toISOString();
+    return hostPlugins.map((plugin) => {
+        const storedPlugin = storedPluginsById.get(plugin.id);
+        return {
+            id: plugin.id,
+            name: pickString(plugin.name, storedPlugin?.name),
+            version: pickString(plugin.version, storedPlugin?.version),
+            description: pickString(plugin.description, storedPlugin?.description),
+            author: pickString(plugin.author, storedPlugin?.author),
+            repository: pickString(plugin.repository, storedPlugin?.repository),
+            thumbnail: pickString(plugin.thumbnail, storedPlugin?.thumbnail),
+            downloadUrl: pickString(plugin.downloadUrl, storedPlugin?.downloadUrl),
+            homepage: pickString(plugin.homepage, storedPlugin?.homepage),
+            tags: Array.isArray(plugin.tags)
+                ? plugin.tags.filter((entry) => typeof entry === 'string')
+                : storedPlugin?.tags ?? [],
+            addedDate: pickString(plugin.addedDate, storedPlugin?.addedDate),
+            installedDate: pickString(plugin.installedDate, storedPlugin?.installedDate) || discoveredAt,
+            enabled: typeof plugin.enabled === 'boolean' ? plugin.enabled : storedPlugin?.enabled ?? true,
+        };
+    });
+}
+function upsertInstalledPlugin(plugins, nextPlugin) {
+    const filteredPlugins = plugins.filter((plugin) => plugin.id !== nextPlugin.id);
+    return [...filteredPlugins, nextPlugin];
+}
+function normalizeInstalledPlugin(value) {
+    if (!value || typeof value !== 'object' || Array.isArray(value)) {
+        return null;
+    }
+    const record = value;
+    const id = typeof record.id === 'string' ? record.id : '';
+    if (!id) {
+        return null;
+    }
+    return {
+        id,
+        name: typeof record.name === 'string' ? record.name : '',
+        version: typeof record.version === 'string' ? record.version : '',
+        description: typeof record.description === 'string' ? record.description : '',
+        author: typeof record.author === 'string' ? record.author : '',
+        repository: typeof record.repository === 'string' ? record.repository : '',
+        thumbnail: typeof record.thumbnail === 'string' ? record.thumbnail : '',
+        downloadUrl: typeof record.downloadUrl === 'string' ? record.downloadUrl : '',
+        homepage: typeof record.homepage === 'string' ? record.homepage : '',
+        tags: Array.isArray(record.tags)
+            ? record.tags.filter((entry) => typeof entry === 'string')
+            : [],
+        addedDate: typeof record.addedDate === 'string' ? record.addedDate : '',
+        installedDate: typeof record.installedDate === 'string' ? record.installedDate : '',
+        enabled: typeof record.enabled === 'boolean' ? record.enabled : true,
+    };
+}
+function pickString(value, fallback = '') {
+    return typeof value === 'string' && value.length > 0 ? value : fallback;
+}
+//# sourceMappingURL=PluginMarketplaceManager.js.map

dist/index.browser.d.ts

@@ -0,0 +1,15 @@
+export type { IPluginStorage, IPluginEventClient, } from './interfaces.js';
+export { MemoryStorage } from './interfaces.js';
+export { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+export type { PluginMarketplaceClientOptions, PluginMarketplaceFetch, PluginMarketplaceResponse, } from './PluginMarketplaceClient.js';
+export { PluginMarketplaceManager } from './PluginMarketplaceManager.js';
+export type { PluginMarketplaceHostAdapter, PluginMarketplaceInstalledRecord, PluginMarketplaceManagerOptions, } from './PluginMarketplaceManager.js';
+export type { PluginMetadata, PluginIndex, InstalledPlugin, } from './types.js';
+export { PluginTab } from './types.js';
+export type { ThemeColorGroup, ThemePaletteGroup, PluginThemeColors, PluginTheme, CommandArg, PluginCommand, MessageInterceptor, MessageContext, CustomRenderer, SettingDefinition, SettingsSchema, NotificationOptions, PluginContext, PluginSettingsSection, UILocation, Plugin, PluginLogEntry, } from './PluginInterfaces.js';
+export { generateThemeCSS } from './theme-css.js';
+export { PluginRegistry } from './PluginRegistry.js';
+export type { PluginRegistryOptions } from './PluginRegistry.js';
+export { createPluginContext } from './PluginContext.js';
+export type { PluginContextOptions } from './PluginContext.js';
+//# sourceMappingURL=index.browser.d.ts.map

dist/index.browser.d.ts.map

@@ -0,0 +1 @@
+{"version":3,"file":"index.browser.d.ts","sourceRoot":"","sources":["../src/index.browser.ts"],"names":[],"mappings":"AAAA,YAAY,EACV,cAAc,EACd,kBAAkB,GACnB,MAAM,iBAAiB,CAAC;AACzB,OAAO,EAAE,aAAa,EAAE,MAAM,iBAAiB,CAAC;AAEhD,OAAO,EAAE,uBAAuB,EAAE,MAAM,8BAA8B,CAAC;AACvE,YAAY,EACV,8BAA8B,EAC9B,sBAAsB,EACtB,yBAAyB,GAC1B,MAAM,8BAA8B,CAAC;AAEtC,OAAO,EAAE,wBAAwB,EAAE,MAAM,+BAA+B,CAAC;AACzE,YAAY,EACV,4BAA4B,EAC5B,gCAAgC,EAChC,+BAA+B,GAChC,MAAM,+BAA+B,CAAC;AAEvC,YAAY,EACV,cAAc,EACd,WAAW,EACX,eAAe,GAChB,MAAM,YAAY,CAAC;AACpB,OAAO,EAAE,SAAS,EAAE,MAAM,YAAY,CAAC;AAEvC,YAAY,EACV,eAAe,EACf,iBAAiB,EACjB,iBAAiB,EACjB,WAAW,EACX,UAAU,EACV,aAAa,EACb,kBAAkB,EAClB,cAAc,EACd,cAAc,EACd,iBAAiB,EACjB,cAAc,EACd,mBAAmB,EACnB,aAAa,EACb,qBAAqB,EACrB,UAAU,EACV,MAAM,EACN,cAAc,GACf,MAAM,uBAAuB,CAAC;AAE/B,OAAO,EAAE,gBAAgB,EAAE,MAAM,gBAAgB,CAAC;AAElD,OAAO,EAAE,cAAc,EAAE,MAAM,qBAAqB,CAAC;AACrD,YAAY,EAAE,qBAAqB,EAAE,MAAM,qBAAqB,CAAC;AAEjE,OAAO,EAAE,mBAAmB,EAAE,MAAM,oBAAoB,CAAC;AACzD,YAAY,EAAE,oBAAoB,EAAE,MAAM,oBAAoB,CAAC"}

dist/index.browser.js

@@ -0,0 +1,8 @@
+export { MemoryStorage } from './interfaces.js';
+export { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+export { PluginMarketplaceManager } from './PluginMarketplaceManager.js';
+export { PluginTab } from './types.js';
+export { generateThemeCSS } from './theme-css.js';
+export { PluginRegistry } from './PluginRegistry.js';
+export { createPluginContext } from './PluginContext.js';
+//# sourceMappingURL=index.browser.js.map

dist/index.browser.js.map

@@ -0,0 +1 @@
+{"version":3,"file":"index.browser.js","sourceRoot":"","sources":["../src/index.browser.ts"],"names":[],"mappings":"AAIA,OAAO,EAAE,aAAa,EAAE,MAAM,iBAAiB,CAAC;AAEhD,OAAO,EAAE,uBAAuB,EAAE,MAAM,8BAA8B,CAAC;AAOvE,OAAO,EAAE,wBAAwB,EAAE,MAAM,+BAA+B,CAAC;AAYzE,OAAO,EAAE,SAAS,EAAE,MAAM,YAAY,CAAC;AAsBvC,OAAO,EAAE,gBAAgB,EAAE,MAAM,gBAAgB,CAAC;AAElD,OAAO,EAAE,cAAc,EAAE,MAAM,qBAAqB,CAAC;AAGrD,OAAO,EAAE,mBAAmB,EAAE,MAAM,oBAAoB,CAAC"}

dist/index.d.ts

@@ -1,5 +1,9 @@
 export type { IPluginStorage, IPluginEventClient, } from './interfaces.js';
 export { MemoryStorage } from './interfaces.js';
+export { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+export type { PluginMarketplaceClientOptions, PluginMarketplaceFetch, PluginMarketplaceResponse, } from './PluginMarketplaceClient.js';
+export { PluginMarketplaceManager } from './PluginMarketplaceManager.js';
+export type { PluginMarketplaceHostAdapter, PluginMarketplaceManagerOptions, } from './PluginMarketplaceManager.js';
 export type { PluginMetadata, PluginIndex, InstalledPlugin, } from './types.js';
 export { PluginTab } from './types.js';
 export type { ThemeColorGroup, ThemePaletteGroup, PluginThemeColors, PluginTheme, CommandArg, PluginCommand, MessageInterceptor, MessageContext, CustomRenderer, SettingDefinition, SettingsSchema, NotificationOptions, PluginContext, PluginSettingsSection, UILocation, Plugin, PluginLogEntry, } from './PluginInterfaces.js';

dist/index.d.ts.map

@@ -1 +1 @@
-{"version":3,"file":"index.d.ts","sourceRoot":"","sources":["../src/index.ts"],"names":[],"mappings":"AAAA,YAAY,EACV,cAAc,EACd,kBAAkB,GACnB,MAAM,iBAAiB,CAAC;AACzB,OAAO,EAAE,aAAa,EAAE,MAAM,iBAAiB,CAAC;AAEhD,YAAY,EACV,cAAc,EACd,WAAW,EACX,eAAe,GAChB,MAAM,YAAY,CAAC;AACpB,OAAO,EAAE,SAAS,EAAE,MAAM,YAAY,CAAC;AAEvC,YAAY,EACV,eAAe,EACf,iBAAiB,EACjB,iBAAiB,EACjB,WAAW,EACX,UAAU,EACV,aAAa,EACb,kBAAkB,EAClB,cAAc,EACd,cAAc,EACd,iBAAiB,EACjB,cAAc,EACd,mBAAmB,EACnB,aAAa,EACb,qBAAqB,EACrB,UAAU,EACV,MAAM,EACN,cAAc,GACf,MAAM,uBAAuB,CAAC;AAE/B,OAAO,EAAE,gBAAgB,EAAE,MAAM,gBAAgB,CAAC;AAElD,OAAO,EAAE,cAAc,EAAE,MAAM,qBAAqB,CAAC;AACrD,YAAY,EAAE,qBAAqB,EAAE,MAAM,qBAAqB,CAAC;AAEjE,OAAO,EAAE,mBAAmB,EAAE,MAAM,oBAAoB,CAAC;AACzD,YAAY,EAAE,oBAAoB,EAAE,MAAM,oBAAoB,CAAC;AAE/D,OAAO,EAAE,YAAY,EAAE,MAAM,mBAAmB,CAAC;AACjD,YAAY,EAAE,mBAAmB,EAAE,MAAM,mBAAmB,CAAC"}
+{"version":3,"file":"index.d.ts","sourceRoot":"","sources":["../src/index.ts"],"names":[],"mappings":"AAAA,YAAY,EACV,cAAc,EACd,kBAAkB,GACnB,MAAM,iBAAiB,CAAC;AACzB,OAAO,EAAE,aAAa,EAAE,MAAM,iBAAiB,CAAC;AAEhD,OAAO,EAAE,uBAAuB,EAAE,MAAM,8BAA8B,CAAC;AACvE,YAAY,EACV,8BAA8B,EAC9B,sBAAsB,EACtB,yBAAyB,GAC1B,MAAM,8BAA8B,CAAC;AAEtC,OAAO,EAAE,wBAAwB,EAAE,MAAM,+BAA+B,CAAC;AACzE,YAAY,EACV,4BAA4B,EAC5B,+BAA+B,GAChC,MAAM,+BAA+B,CAAC;AAEvC,YAAY,EACV,cAAc,EACd,WAAW,EACX,eAAe,GAChB,MAAM,YAAY,CAAC;AACpB,OAAO,EAAE,SAAS,EAAE,MAAM,YAAY,CAAC;AAEvC,YAAY,EACV,eAAe,EACf,iBAAiB,EACjB,iBAAiB,EACjB,WAAW,EACX,UAAU,EACV,aAAa,EACb,kBAAkB,EAClB,cAAc,EACd,cAAc,EACd,iBAAiB,EACjB,cAAc,EACd,mBAAmB,EACnB,aAAa,EACb,qBAAqB,EACrB,UAAU,EACV,MAAM,EACN,cAAc,GACf,MAAM,uBAAuB,CAAC;AAE/B,OAAO,EAAE,gBAAgB,EAAE,MAAM,gBAAgB,CAAC;AAElD,OAAO,EAAE,cAAc,EAAE,MAAM,qBAAqB,CAAC;AACrD,YAAY,EAAE,qBAAqB,EAAE,MAAM,qBAAqB,CAAC;AAEjE,OAAO,EAAE,mBAAmB,EAAE,MAAM,oBAAoB,CAAC;AACzD,YAAY,EAAE,oBAAoB,EAAE,MAAM,oBAAoB,CAAC;AAE/D,OAAO,EAAE,YAAY,EAAE,MAAM,mBAAmB,CAAC;AACjD,YAAY,EAAE,mBAAmB,EAAE,MAAM,mBAAmB,CAAC"}

dist/index.js

@@ -1,4 +1,6 @@
 export { MemoryStorage } from './interfaces.js';
+export { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+export { PluginMarketplaceManager } from './PluginMarketplaceManager.js';
 export { PluginTab } from './types.js';
 export { generateThemeCSS } from './theme-css.js';
 export { PluginRegistry } from './PluginRegistry.js';

dist/index.js.map

@@ -1 +1 @@
-{"version":3,"file":"index.js","sourceRoot":"","sources":["../src/index.ts"],"names":[],"mappings":"AAIA,OAAO,EAAE,aAAa,EAAE,MAAM,iBAAiB,CAAC;AAOhD,OAAO,EAAE,SAAS,EAAE,MAAM,YAAY,CAAC;AAsBvC,OAAO,EAAE,gBAAgB,EAAE,MAAM,gBAAgB,CAAC;AAElD,OAAO,EAAE,cAAc,EAAE,MAAM,qBAAqB,CAAC;AAGrD,OAAO,EAAE,mBAAmB,EAAE,MAAM,oBAAoB,CAAC;AAGzD,OAAO,EAAE,YAAY,EAAE,MAAM,mBAAmB,CAAC"}
+{"version":3,"file":"index.js","sourceRoot":"","sources":["../src/index.ts"],"names":[],"mappings":"AAIA,OAAO,EAAE,aAAa,EAAE,MAAM,iBAAiB,CAAC;AAEhD,OAAO,EAAE,uBAAuB,EAAE,MAAM,8BAA8B,CAAC;AAOvE,OAAO,EAAE,wBAAwB,EAAE,MAAM,+BAA+B,CAAC;AAWzE,OAAO,EAAE,SAAS,EAAE,MAAM,YAAY,CAAC;AAsBvC,OAAO,EAAE,gBAAgB,EAAE,MAAM,gBAAgB,CAAC;AAElD,OAAO,EAAE,cAAc,EAAE,MAAM,qBAAqB,CAAC;AAGrD,OAAO,EAAE,mBAAmB,EAAE,MAAM,oBAAoB,CAAC;AAGzD,OAAO,EAAE,YAAY,EAAE,MAAM,mBAAmB,CAAC"}

package.json

@@ -7,6 +7,7 @@
   "types": "./dist/index.d.ts",
   "exports": {
     ".": {
+      "browser": "./dist/index.browser.js",
       "import": "./dist/index.js",
       "types": "./dist/index.d.ts"
     }

src/PluginMarketplaceClient.ts

@@ -0,0 +1,149 @@
+import type { PluginIndex, PluginMetadata } from './types.js';
+
+/**
+ * Minimal response shape required by marketplace client.
+ */
+export interface PluginMarketplaceResponse {
+  ok: boolean;
+  status: number;
+  json(): Promise<unknown>;
+}
+
+/**
+ * Fetch function used by marketplace client.
+ */
+export type PluginMarketplaceFetch = (
+  input: string,
+  init?: Record<string, unknown>
+) => Promise<PluginMarketplaceResponse>;
+
+/**
+ * Construction options for {@link PluginMarketplaceClient}.
+ */
+export interface PluginMarketplaceClientOptions {
+  /** URL of marketplace index JSON file. */
+  indexUrl: string;
+
+  /** Base URL used to resolve `${pluginId}.json` metadata files. */
+  baseUrl: string;
+
+  /** Optional fetch implementation. Falls back to global `fetch`. */
+  fetchFn?: PluginMarketplaceFetch;
+}
+
+/**
+ * Host-agnostic client for reading marketplace metadata.
+ */
+export class PluginMarketplaceClient {
+  private readonly indexUrl: string;
+  private readonly baseUrl: string;
+  private readonly fetchFn?: PluginMarketplaceFetch;
+
+  constructor(options: PluginMarketplaceClientOptions) {
+    this.indexUrl = options.indexUrl;
+    this.baseUrl = options.baseUrl;
+    this.fetchFn = options.fetchFn;
+  }
+
+  /**
+   * Fetches and validates marketplace index.
+   */
+  async fetchIndex(): Promise<PluginIndex> {
+    const response = await this.getFetchFn()(this.indexUrl);
+
+    if (!response.ok) {
+      throw new Error(`Failed to fetch plugin index: HTTP ${response.status}`);
+    }
+
+    return normalizePluginIndex(await response.json());
+  }
+
+  /**
+   * Fetches and validates single plugin metadata entry.
+   *
+   * @param pluginId - Identifier referenced by marketplace index.
+   */
+  async fetchPlugin(pluginId: string): Promise<PluginMetadata> {
+    const response = await this.getFetchFn()(this.buildMetadataUrl(pluginId));
+
+    if (!response.ok) {
+      throw new Error(`Failed to fetch plugin ${pluginId}: HTTP ${response.status}`);
+    }
+
+    return normalizePluginMetadata(await response.json(), pluginId);
+  }
+
+  /**
+   * Fetches full marketplace catalog.
+   *
+   * Entries that fail fetch or validation get skipped so host can still render
+   * rest of catalog.
+   */
+  async fetchPlugins(): Promise<PluginMetadata[]> {
+    const index = await this.fetchIndex();
+    const results = await Promise.allSettled(index.plugins.map((pluginId) => this.fetchPlugin(pluginId)));
+
+    return results.flatMap((result) => (result.status === 'fulfilled' ? [result.value] : []));
+  }
+
+  private buildMetadataUrl(pluginId: string): string {
+    const trimmedBaseUrl = this.baseUrl.endsWith('/') ? this.baseUrl : `${this.baseUrl}/`;
+    return `${trimmedBaseUrl}${pluginId}.json`;
+  }
+
+  private getFetchFn(): PluginMarketplaceFetch {
+    if (this.fetchFn) {
+      return this.fetchFn;
+    }
+
+    if (typeof fetch !== 'function') {
+      throw new Error('No fetch implementation available for PluginMarketplaceClient');
+    }
+
+    return fetch as unknown as PluginMarketplaceFetch;
+  }
+}
+
+function normalizePluginIndex(value: unknown): PluginIndex {
+  const record = asRecord(value, 'Plugin index payload must be object');
+
+  return {
+    version: asString(record.version),
+    updatedAt: asString(record.updatedAt),
+    plugins: Array.isArray(record.plugins)
+      ? record.plugins.filter((entry): entry is string => typeof entry === 'string')
+      : [],
+  };
+}
+
+function normalizePluginMetadata(value: unknown, fallbackId: string): PluginMetadata {
+  const record = asRecord(value, `Plugin metadata for ${fallbackId} must be object`);
+
+  return {
+    id: asString(record.id) || fallbackId,
+    name: asString(record.name),
+    version: asString(record.version),
+    description: asString(record.description),
+    author: asString(record.author),
+    repository: asString(record.repository),
+    thumbnail: asString(record.thumbnail),
+    downloadUrl: asString(record.downloadUrl),
+    homepage: asString(record.homepage),
+    tags: Array.isArray(record.tags)
+      ? record.tags.filter((entry): entry is string => typeof entry === 'string')
+      : [],
+    addedDate: asString(record.addedDate),
+  };
+}
+
+function asRecord(value: unknown, message: string): Record<string, unknown> {
+  if (!value || typeof value !== 'object' || Array.isArray(value)) {
+    throw new Error(message);
+  }
+
+  return value as Record<string, unknown>;
+}
+
+function asString(value: unknown): string {
+  return typeof value === 'string' ? value : '';
+}

src/PluginMarketplaceManager.ts

@@ -0,0 +1,262 @@
+import { MemoryStorage, type IPluginStorage } from './interfaces.js';
+import type { PluginRegistry } from './PluginRegistry.js';
+import type { InstalledPlugin, PluginMetadata } from './types.js';
+import { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+
+const DEFAULT_INSTALLED_PLUGINS_STORAGE_KEY = 'plugin-manager:installed-plugins';
+
+/**
+ * Host-visible installed-plugin metadata.
+ *
+ * Hosts may only know filesystem facts such as `id`, `name`, or `installedDate`.
+ * Stored marketplace metadata fills remaining fields.
+ */
+export type PluginMarketplaceInstalledRecord = Partial<InstalledPlugin> & Pick<InstalledPlugin, 'id'>;
+
+/**
+ * Host callbacks used by {@link PluginMarketplaceManager}.
+ */
+export interface PluginMarketplaceHostAdapter {
+  /**
+   * Returns host-known installed plugins.
+   */
+  listInstalledPlugins?(): Promise<PluginMarketplaceInstalledRecord[]>;
+
+  /**
+   * Performs host-specific install side effects.
+   */
+  installPlugin?(plugin: PluginMetadata): Promise<void>;
+
+  /**
+   * Performs host-specific uninstall side effects.
+   */
+  uninstallPlugin?(pluginId: string): Promise<void>;
+}
+
+/**
+ * Construction options for {@link PluginMarketplaceManager}.
+ */
+export interface PluginMarketplaceManagerOptions {
+  /** Shared marketplace client used to query remote metadata. */
+  client: PluginMarketplaceClient;
+
+  /** Optional persistent storage for installed-plugin state. */
+  storage?: IPluginStorage;
+
+  /** Optional host adapter for install and discovery side effects. */
+  host?: PluginMarketplaceHostAdapter;
+
+  /** Optional registry used when disabling or uninstalling loaded plugins. */
+  registry?: PluginRegistry;
+
+  /** Optional override for installed-plugin storage key. */
+  installedPluginsStorageKey?: string;
+}
+
+/**
+ * Coordinates marketplace reads with host-specific install and enable state.
+ */
+export class PluginMarketplaceManager {
+  private readonly client: PluginMarketplaceClient;
+  private readonly storage: IPluginStorage;
+  private readonly host?: PluginMarketplaceHostAdapter;
+  private readonly registry?: PluginRegistry;
+  private readonly installedPluginsStorageKey: string;
+
+  constructor(options: PluginMarketplaceManagerOptions) {
+    this.client = options.client;
+    this.storage = options.storage ?? new MemoryStorage();
+    this.host = options.host;
+    this.registry = options.registry;
+    this.installedPluginsStorageKey =
+      options.installedPluginsStorageKey ?? DEFAULT_INSTALLED_PLUGINS_STORAGE_KEY;
+  }
+
+  /**
+   * Fetches full marketplace catalog.
+   */
+  async fetchMarketplacePlugins(): Promise<PluginMetadata[]> {
+    return this.client.fetchPlugins();
+  }
+
+  /**
+   * Lists installed plugins merged with persisted enabled state.
+   */
+  async listInstalledPlugins(): Promise<InstalledPlugin[]> {
+    const storedPlugins = this.readStoredInstalledPlugins();
+
+    if (!this.host?.listInstalledPlugins) {
+      return storedPlugins;
+    }
+
+    const hostPlugins = await this.host.listInstalledPlugins();
+    const mergedPlugins = mergeInstalledPlugins(hostPlugins, storedPlugins);
+    this.writeStoredInstalledPlugins(mergedPlugins);
+    return mergedPlugins;
+  }
+
+  /**
+   * Lists installed plugins currently enabled.
+   */
+  async listEnabledPlugins(): Promise<InstalledPlugin[]> {
+    return (await this.listInstalledPlugins()).filter((plugin) => plugin.enabled);
+  }
+
+  /**
+   * Returns whether plugin is recorded as installed.
+   */
+  async isPluginInstalled(pluginId: string): Promise<boolean> {
+    return (await this.listInstalledPlugins()).some((plugin) => plugin.id === pluginId);
+  }
+
+  /**
+   * Installs marketplace plugin via host adapter and persists state.
+   */
+  async installPlugin(plugin: PluginMetadata): Promise<InstalledPlugin> {
+    await this.host?.installPlugin?.(plugin);
+
+    const installedPlugin: InstalledPlugin = {
+      ...plugin,
+      installedDate: new Date().toISOString(),
+      enabled: true,
+    };
+
+    const updatedPlugins = upsertInstalledPlugin(this.readStoredInstalledPlugins(), installedPlugin);
+    this.writeStoredInstalledPlugins(updatedPlugins);
+
+    return updatedPlugins.find((entry) => entry.id === plugin.id) ?? installedPlugin;
+  }
+
+  /**
+   * Removes plugin from host and clears persisted install state.
+   */
+  async uninstallPlugin(pluginId: string): Promise<void> {
+    if (this.registry) {
+      await this.registry.unregisterPlugin(pluginId);
+    }
+
+    await this.host?.uninstallPlugin?.(pluginId);
+    this.writeStoredInstalledPlugins(
+      this.readStoredInstalledPlugins().filter((plugin) => plugin.id !== pluginId)
+    );
+  }
+
+  /**
+   * Enables or disables installed plugin.
+   *
+   * Disabling triggers `registry.unregisterPlugin` when registry exists.
+   * Enabling only updates persisted state; host controls actual load timing.
+   */
+  async setPluginEnabled(pluginId: string, enabled: boolean): Promise<InstalledPlugin | null> {
+    if (!enabled && this.registry) {
+      await this.registry.unregisterPlugin(pluginId);
+    }
+
+    const installedPlugins = await this.listInstalledPlugins();
+    const targetPlugin = installedPlugins.find((plugin) => plugin.id === pluginId);
+
+    if (!targetPlugin) {
+      return null;
+    }
+
+    const updatedPlugin: InstalledPlugin = { ...targetPlugin, enabled };
+    this.writeStoredInstalledPlugins(upsertInstalledPlugin(installedPlugins, updatedPlugin));
+    return updatedPlugin;
+  }
+
+  private readStoredInstalledPlugins(): InstalledPlugin[] {
+    const rawValue = this.storage.getItem(this.installedPluginsStorageKey);
+
+    if (!rawValue) {
+      return [];
+    }
+
+    try {
+      const parsedValue = JSON.parse(rawValue) as unknown;
+
+      if (!Array.isArray(parsedValue)) {
+        return [];
+      }
+
+      return parsedValue
+        .map((entry) => normalizeInstalledPlugin(entry))
+        .filter((entry): entry is InstalledPlugin => entry !== null);
+    } catch {
+      return [];
+    }
+  }
+
+  private writeStoredInstalledPlugins(plugins: InstalledPlugin[]): void {
+    this.storage.setItem(this.installedPluginsStorageKey, JSON.stringify(plugins));
+  }
+}
+
+function mergeInstalledPlugins(
+  hostPlugins: PluginMarketplaceInstalledRecord[],
+  storedPlugins: InstalledPlugin[]
+): InstalledPlugin[] {
+  const storedPluginsById = new Map(storedPlugins.map((plugin) => [plugin.id, plugin]));
+  const discoveredAt = new Date().toISOString();
+
+  return hostPlugins.map((plugin) => {
+    const storedPlugin = storedPluginsById.get(plugin.id);
+
+    return {
+      id: plugin.id,
+      name: pickString(plugin.name, storedPlugin?.name),
+      version: pickString(plugin.version, storedPlugin?.version),
+      description: pickString(plugin.description, storedPlugin?.description),
+      author: pickString(plugin.author, storedPlugin?.author),
+      repository: pickString(plugin.repository, storedPlugin?.repository),
+      thumbnail: pickString(plugin.thumbnail, storedPlugin?.thumbnail),
+      downloadUrl: pickString(plugin.downloadUrl, storedPlugin?.downloadUrl),
+      homepage: pickString(plugin.homepage, storedPlugin?.homepage),
+      tags: Array.isArray(plugin.tags)
+        ? plugin.tags.filter((entry): entry is string => typeof entry === 'string')
+        : storedPlugin?.tags ?? [],
+      addedDate: pickString(plugin.addedDate, storedPlugin?.addedDate),
+      installedDate: pickString(plugin.installedDate, storedPlugin?.installedDate) || discoveredAt,
+      enabled: typeof plugin.enabled === 'boolean' ? plugin.enabled : storedPlugin?.enabled ?? true,
+    };
+  });
+}
+
+function upsertInstalledPlugin(plugins: InstalledPlugin[], nextPlugin: InstalledPlugin): InstalledPlugin[] {
+  const filteredPlugins = plugins.filter((plugin) => plugin.id !== nextPlugin.id);
+  return [...filteredPlugins, nextPlugin];
+}
+
+function normalizeInstalledPlugin(value: unknown): InstalledPlugin | null {
+  if (!value || typeof value !== 'object' || Array.isArray(value)) {
+    return null;
+  }
+
+  const record = value as Record<string, unknown>;
+  const id = typeof record.id === 'string' ? record.id : '';
+
+  if (!id) {
+    return null;
+  }
+
+  return {
+    id,
+    name: typeof record.name === 'string' ? record.name : '',
+    version: typeof record.version === 'string' ? record.version : '',
+    description: typeof record.description === 'string' ? record.description : '',
+    author: typeof record.author === 'string' ? record.author : '',
+    repository: typeof record.repository === 'string' ? record.repository : '',
+    thumbnail: typeof record.thumbnail === 'string' ? record.thumbnail : '',
+    downloadUrl: typeof record.downloadUrl === 'string' ? record.downloadUrl : '',
+    homepage: typeof record.homepage === 'string' ? record.homepage : '',
+    tags: Array.isArray(record.tags)
+      ? record.tags.filter((entry): entry is string => typeof entry === 'string')
+      : [],
+    addedDate: typeof record.addedDate === 'string' ? record.addedDate : '',
+    installedDate: typeof record.installedDate === 'string' ? record.installedDate : '',
+    enabled: typeof record.enabled === 'boolean' ? record.enabled : true,
+  };
+}
+
+function pickString(value: unknown, fallback = ''): string {
+  return typeof value === 'string' && value.length > 0 ? value : fallback;
+}

src/index.browser.ts

@@ -0,0 +1,54 @@
+export type {
+  IPluginStorage,
+  IPluginEventClient,
+} from './interfaces.js';
+export { MemoryStorage } from './interfaces.js';
+
+export { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+export type {
+  PluginMarketplaceClientOptions,
+  PluginMarketplaceFetch,
+  PluginMarketplaceResponse,
+} from './PluginMarketplaceClient.js';
+
+export { PluginMarketplaceManager } from './PluginMarketplaceManager.js';
+export type {
+  PluginMarketplaceHostAdapter,
+  PluginMarketplaceInstalledRecord,
+  PluginMarketplaceManagerOptions,
+} from './PluginMarketplaceManager.js';
+
+export type {
+  PluginMetadata,
+  PluginIndex,
+  InstalledPlugin,
+} from './types.js';
+export { PluginTab } from './types.js';
+
+export type {
+  ThemeColorGroup,
+  ThemePaletteGroup,
+  PluginThemeColors,
+  PluginTheme,
+  CommandArg,
+  PluginCommand,
+  MessageInterceptor,
+  MessageContext,
+  CustomRenderer,
+  SettingDefinition,
+  SettingsSchema,
+  NotificationOptions,
+  PluginContext,
+  PluginSettingsSection,
+  UILocation,
+  Plugin,
+  PluginLogEntry,
+} from './PluginInterfaces.js';
+
+export { generateThemeCSS } from './theme-css.js';
+
+export { PluginRegistry } from './PluginRegistry.js';
+export type { PluginRegistryOptions } from './PluginRegistry.js';
+
+export { createPluginContext } from './PluginContext.js';
+export type { PluginContextOptions } from './PluginContext.js';

src/index.ts

@@ -4,6 +4,19 @@ export type {
 } from './interfaces.js';
 export { MemoryStorage } from './interfaces.js';
 
+export { PluginMarketplaceClient } from './PluginMarketplaceClient.js';
+export type {
+  PluginMarketplaceClientOptions,
+  PluginMarketplaceFetch,
+  PluginMarketplaceResponse,
+} from './PluginMarketplaceClient.js';
+
+export { PluginMarketplaceManager } from './PluginMarketplaceManager.js';
+export type {
+  PluginMarketplaceHostAdapter,
+  PluginMarketplaceManagerOptions,
+} from './PluginMarketplaceManager.js';
+
 export type {
   PluginMetadata,
   PluginIndex,

test/electron/renderer.js

@@ -14,7 +14,12 @@
   const pmEntry = path.join(
     __dirname, 'node_modules', '@paarrot', 'plugin-manager', 'dist', 'index.js'
   );
-  const { PluginRegistry, createPluginContext } = await import(pathToFileURL(pmEntry).href);
+  const {
+    PluginMarketplaceClient,
+    PluginMarketplaceManager,
+    PluginRegistry,
+    createPluginContext,
+  } = await import(pathToFileURL(pmEntry).href);
 
   // ---------------------------------------------------------------------------
   // Module loader — supports both CJS (module.exports) and ESM (export default)
@@ -149,6 +154,11 @@
     },
   });
 
+  const marketplaceClient = new PluginMarketplaceClient({
+    indexUrl: 'https://raw.githubusercontent.com/Paarrot/Plugin-Directory/refs/heads/main/plugins/index.json',
+    baseUrl: 'https://raw.githubusercontent.com/Paarrot/Plugin-Directory/refs/heads/main/plugins/',
+  });
+
   // ---------------------------------------------------------------------------
   // Load the example plugin from disk (CJS eval — same pattern as cinny)
   // ---------------------------------------------------------------------------
@@ -180,7 +190,20 @@
    * Persistent record of every plugin we have ever seen, keyed by plugin id.
    * Survives unload so the Installed list can show a Reload button.
    *
-   * @type {Map<string, { name: string, version: string, pluginModule: object, filePath?: string, downloadUrl?: string }>}
+  * @type {Map<string, {
+  *   name: string,
+  *   version: string,
+  *   pluginModule: object,
+  *   filePath?: string,
+  *   downloadUrl?: string,
+  *   description?: string,
+  *   author?: string,
+  *   repository?: string,
+  *   thumbnail?: string,
+  *   homepage?: string,
+  *   tags?: string[],
+  *   addedDate?: string
+  * }>}
    */
   const knownPlugins = new Map();
 
@@ -189,7 +212,19 @@
    * registers and loads the plugin, then records it in knownPlugins.
    * @param {string} id
    * @param {object} pluginModule
-   * @param {{ filePath?: string, downloadUrl?: string }} [source]
+  * @param {{
+  *   filePath?: string,
+  *   downloadUrl?: string,
+  *   name?: string,
+  *   version?: string,
+  *   description?: string,
+  *   author?: string,
+  *   repository?: string,
+  *   thumbnail?: string,
+  *   homepage?: string,
+  *   tags?: string[],
+  *   addedDate?: string,
+  * }} [source]
    */
   async function registerAndLoad(id, pluginModule, source = {}) {
     const ctx = createPluginContext(
@@ -211,13 +246,60 @@
     await pluginModule.onLoad(ctx);
 
     knownPlugins.set(id, {
-      name:         pluginModule.name    ?? id,
-      version:      pluginModule.version ?? '?',
+      name:         source.name ?? pluginModule.name ?? id,
+      version:      source.version ?? pluginModule.version ?? '?',
       pluginModule,
       ...source,
     });
   }
 
+  const marketplace = new PluginMarketplaceManager({
+    client: marketplaceClient,
+    storage: localStorage,
+    registry,
+    host: {
+      listInstalledPlugins: async () => Array.from(knownPlugins.entries()).map(([id, known]) => ({
+        id,
+        name: known.name ?? id,
+        version: known.version ?? '',
+        description: known.description ?? '',
+        author: known.author ?? '',
+        repository: known.repository ?? '',
+        thumbnail: known.thumbnail ?? '',
+        downloadUrl: known.downloadUrl ?? '',
+        homepage: known.homepage ?? '',
+        tags: Array.isArray(known.tags) ? known.tags : [],
+        addedDate: known.addedDate ?? '',
+      })),
+      installPlugin: async (pluginMetadata) => {
+        if (!pluginMetadata.downloadUrl) {
+          throw new Error(`No download URL for plugin ${pluginMetadata.id}`);
+        }
+
+        addLog(`Downloading plugin ${pluginMetadata.id}…`, 'info');
+        const code = await fetchPluginCode(pluginMetadata.downloadUrl, pluginMetadata.repository);
+        const raw = await evalPluginCode(code);
+        const pluginModule = normalisePlugin(raw);
+
+        await registerAndLoad(pluginMetadata.id, pluginModule, {
+          downloadUrl: pluginMetadata.downloadUrl,
+          name: pluginMetadata.name,
+          version: pluginMetadata.version,
+          description: pluginMetadata.description,
+          author: pluginMetadata.author,
+          repository: pluginMetadata.repository,
+          thumbnail: pluginMetadata.thumbnail,
+          homepage: pluginMetadata.homepage,
+          tags: pluginMetadata.tags,
+          addedDate: pluginMetadata.addedDate,
+        });
+      },
+      uninstallPlugin: async (pluginId) => {
+        knownPlugins.delete(pluginId);
+      },
+    },
+  });
+
   await registerAndLoad('example-plugin', plugin, {
     filePath: pluginPath,
   });
@@ -367,11 +449,6 @@
   // ---------------------------------------------------------------------------
   // Plugin Directory — fetch from remote index
   // ---------------------------------------------------------------------------
-  const PLUGIN_INDEX_URL =
-    'https://raw.githubusercontent.com/Paarrot/Plugin-Directory/refs/heads/main/plugins/index.json';
-  const PLUGIN_BASE_URL =
-    'https://raw.githubusercontent.com/Paarrot/Plugin-Directory/refs/heads/main/plugins/';
-
   let directoryPlugins = [];
   const dirStatusEl = document.getElementById('dir-status');
   const dirListEl   = document.getElementById('dir-list');
@@ -415,11 +492,7 @@
             ${(p.tags ?? []).map(t => `<span class="market-tag">${t}</span>`).join('')}
             ${p.homepage ? `<a href="${p.homepage}" target="_blank"
               style="font-size:10px;color:#7986cb;text-decoration:none;margin-left:auto;margin-right:6px;">↗ Homepage</a>` : ''}
-            <button class="market-install-btn"
-              data-url="${p.downloadUrl ?? ''}"
-              data-repo="${p.repository ?? ''}"
-              data-id="${p.id}"
-              ${isLoaded ? 'disabled' : ''}>
+            <button class="market-install-btn" data-id="${p.id}" ${isLoaded ? 'disabled' : ''}>
               ${isLoaded ? 'Loaded' : 'Download'}
             </button>
           </div>
@@ -428,24 +501,21 @@
     }).join('');
 
     dirListEl.querySelectorAll('.market-install-btn:not([disabled])').forEach(btn => {
-      btn.addEventListener('click', () => downloadAndLoadPlugin(btn.dataset.id, btn.dataset.url, btn.dataset.repo));
+      btn.addEventListener('click', () => downloadAndLoadPlugin(btn.dataset.id));
     });
   }
 
   /** Downloads a plugin's index.js from the marketplace and loads it into the registry. */
-  async function downloadAndLoadPlugin(pluginId, downloadUrl, repositoryUrl) {
-    if (!downloadUrl) {
-      addLog(`No download URL for plugin ${pluginId}`, 'error');
+  async function downloadAndLoadPlugin(pluginId) {
+    const pluginMetadata = directoryPlugins.find((entry) => entry.id === pluginId);
+
+    if (!pluginMetadata) {
+      addLog(`Plugin ${pluginId} is not present in directory cache`, 'error');
       return;
     }
+
     try {
-      addLog(`Downloading plugin ${pluginId}…`, 'info');
-      const code = await fetchPluginCode(downloadUrl, repositoryUrl);
-      const raw  = await evalPluginCode(code);
-      const p    = normalisePlugin(raw);
-
-      await registerAndLoad(pluginId, p, { downloadUrl });
-
+      await marketplace.installPlugin(pluginMetadata);
       addLog(`Plugin installed from directory: ${pluginId}`, 'success');
       refreshPluginList();
       refreshCommandList();
@@ -460,23 +530,9 @@
   async function fetchDirectory() {
     dirStatusEl.textContent = 'Fetching plugin directory…';
     dirListEl.innerHTML = '';
+
     try {
-      const indexRes = await fetch(PLUGIN_INDEX_URL);
-      if (!indexRes.ok) throw new Error(`HTTP ${indexRes.status}`);
-      const index = await indexRes.json();
-
-      const metas = await Promise.all(
-        index.plugins.map(async (id) => {
-          try {
-            const r = await fetch(`${PLUGIN_BASE_URL}${id}.json`);
-            return r.ok ? r.json() : null;
-          } catch {
-            return null;
-          }
-        })
-      );
-
-      directoryPlugins = metas.filter(Boolean);
+      directoryPlugins = await marketplace.fetchMarketplacePlugins();
       dirStatusEl.textContent = `${directoryPlugins.length} plugin${directoryPlugins.length !== 1 ? 's' : ''} in directory.`;
       addLog(`Plugin directory fetched: ${directoryPlugins.length} entries`, 'success');
       renderDirectoryList(dirSearchEl.value);