/**
* Plugin Configuration Module
*
* Fetches configuration from server via HTTP API
* Falls back to localStorage for offline/resilience
*/
export interface PluginConfig {
websocketPort: number;
serverUrl: string;
}
export const DEFAULT_PLUGIN_CONFIG: PluginConfig = {
websocketPort: 3333,
serverUrl: "",
};
const PLUGIN_CONFIG_KEY = "drawio-mcp-plugin-config";
let cachedConfig: PluginConfig | null = null;
export async function fetchPluginConfig(): Promise<PluginConfig> {
if (cachedConfig) {
return cachedConfig;
}
try {
const response = await fetch("/api/config");
if (response.ok) {
const serverConfig = await response.json();
cachedConfig = {
websocketPort:
serverConfig.websocketPort || DEFAULT_PLUGIN_CONFIG.websocketPort,
serverUrl: serverConfig.serverUrl || window.location.origin,
};
writePluginConfig(cachedConfig);
return cachedConfig;
}
} catch (error) {
console.warn("[pluginConfig] Failed to fetch config from server:", error);
}
return readPluginConfig();
}
export function readPluginConfig(): PluginConfig {
try {
const stored = localStorage.getItem(PLUGIN_CONFIG_KEY);
if (stored) {
const parsed = JSON.parse(stored);
const validated = validatePluginConfig(parsed);
if (validated.isValid && validated.config) {
return validated.config;
}
}
} catch (error) {
console.warn("[pluginConfig] Failed to read from localStorage:", error);
}
return { ...DEFAULT_PLUGIN_CONFIG };
}
export function writePluginConfig(config: PluginConfig): void {
try {
localStorage.setItem(PLUGIN_CONFIG_KEY, JSON.stringify(config));
cachedConfig = config;
} catch (error) {
console.error("[pluginConfig] Failed to write to localStorage:", error);
throw error;
}
}
export function createDefaultPluginConfig(
partial?: Partial<PluginConfig>,
): PluginConfig {
return {
websocketPort:
partial?.websocketPort ?? DEFAULT_PLUGIN_CONFIG.websocketPort,
serverUrl: partial?.serverUrl ?? DEFAULT_PLUGIN_CONFIG.serverUrl,
};
}
export function validatePluginConfig(config: unknown): {
isValid: boolean;
config?: PluginConfig;
error?: string;
} {
if (!config || typeof config !== "object") {
return { isValid: false, error: "Configuration must be an object" };
}
const cfg = config as any;
if (typeof cfg.websocketPort !== "number") {
return { isValid: false, error: "websocketPort must be a number" };
}
if (cfg.websocketPort < 1024 || cfg.websocketPort > 65535) {
return {
isValid: false,
error: "websocketPort must be between 1024 and 65535",
};
}
return {
isValid: true,
config: {
websocketPort: cfg.websocketPort,
serverUrl: cfg.serverUrl || "",
},
};
}
export function buildWebSocketUrl(config: PluginConfig): string {
const host = window.location.hostname;
return `ws://${host}:${config.websocketPort}`;
}
export function resetPluginConfigToDefaults(): void {
try {
localStorage.removeItem(PLUGIN_CONFIG_KEY);
cachedConfig = null;
} catch (error) {
console.error("[pluginConfig] Failed to reset config:", error);
throw error;
}
}
