/**
 * ActiveCampaign MCP Server Class
 * Implements lazy-loaded tool modules for optimal performance
 */

import { Server } from '@modelcontextprotocol/sdk/server/index.js';
import {
  CallToolRequestSchema,
  ListToolsRequestSchema,
  ListResourcesRequestSchema,
  ReadResourceRequestSchema,
} from '@modelcontextprotocol/sdk/types.js';
import { ActiveCampaignClient } from './client/index.js';

type ToolModule = Record<string, any>;

// Available app resources
const APPS = [
  'contact-manager',
  'deal-pipeline',
  'list-builder',
  'campaign-dashboard',
  'automation-builder',
  'form-manager',
  'tag-organizer',
  'task-center',
  'notes-viewer',
  'pipeline-settings',
  'account-directory',
  'webhook-manager',
  'email-analytics',
  'segment-viewer',
  'site-tracking',
  'score-dashboard',
];

export class ActiveCampaignMCPServer {
  private server: Server;
  private client: ActiveCampaignClient;
  private toolModules: Map<string, () => Promise<ToolModule>>;
  private loadedTools: ToolModule | null = null;

  constructor(client: ActiveCampaignClient) {
    this.client = client;
    this.toolModules = new Map();

    this.server = new Server(
      {
        name: 'activecampaign-server',
        version: '1.0.0',
      },
      {
        capabilities: {
          tools: {},
          resources: {},
        },
      }
    );

    this.setupToolModules();
    this.setupHandlers();
  }

  private setupToolModules() {
    // Register lazy-loaded tool modules
    this.toolModules.set('contacts', async () => {
      const module = await import('./tools/contacts.js');
      return module.createContactTools(this.client);
    });

    this.toolModules.set('deals', async () => {
      const module = await import('./tools/deals.js');
      return module.createDealTools(this.client);
    });

    this.toolModules.set('lists', async () => {
      const module = await import('./tools/lists.js');
      return module.createListTools(this.client);
    });

    this.toolModules.set('campaigns', async () => {
      const module = await import('./tools/campaigns.js');
      return module.createCampaignTools(this.client);
    });

    this.toolModules.set('automations', async () => {
      const module = await import('./tools/automations.js');
      return module.createAutomationTools(this.client);
    });

    this.toolModules.set('forms', async () => {
      const module = await import('./tools/forms.js');
      return module.createFormTools(this.client);
    });

    this.toolModules.set('tags', async () => {
      const module = await import('./tools/tags.js');
      return module.createTagTools(this.client);
    });

    this.toolModules.set('tasks', async () => {
      const module = await import('./tools/tasks.js');
      return module.createTaskTools(this.client);
    });

    this.toolModules.set('notes', async () => {
      const module = await import('./tools/notes.js');
      return module.createNoteTools(this.client);
    });

    this.toolModules.set('pipelines', async () => {
      const module = await import('./tools/pipelines.js');
      return module.createPipelineTools(this.client);
    });

    this.toolModules.set('accounts', async () => {
      const module = await import('./tools/accounts.js');
      return module.createAccountTools(this.client);
    });

    this.toolModules.set('webhooks', async () => {
      const module = await import('./tools/webhooks.js');
      return module.createWebhookTools(this.client);
    });
  }

  private async loadAllTools(): Promise<ToolModule> {
    if (this.loadedTools) {
      return this.loadedTools;
    }

    const allTools: ToolModule = {};
    
    for (const [name, loader] of this.toolModules.entries()) {
      const tools = await loader();
      Object.assign(allTools, tools);
    }

    this.loadedTools = allTools;
    return allTools;
  }

  private setupHandlers() {
    // List available tools
    this.server.setRequestHandler(ListToolsRequestSchema, async () => {
      const allTools = await this.loadAllTools();
      
      return {
        tools: Object.entries(allTools).map(([name, tool]) => ({
          name,
          description: tool.description,
          inputSchema: tool.inputSchema,
        })),
      };
    });

    // Execute tool
    this.server.setRequestHandler(CallToolRequestSchema, async (request) => {
      const allTools = await this.loadAllTools();
      const toolName = request.params.name;
      const tool = allTools[toolName];

      if (!tool) {
        throw new Error(`Unknown tool: ${toolName}`);
      }

      try {
        const result = await tool.handler(request.params.arguments || {});
        return {
          content: [
            {
              type: 'text',
              text: JSON.stringify(result, null, 2),
            },
          ],
        };
      } catch (error) {
        return {
          content: [
            {
              type: 'text',
              text: `Error: ${error instanceof Error ? error.message : String(error)}`,
            },
          ],
          isError: true,
        };
      }
    });

    // List app resources
    this.server.setRequestHandler(ListResourcesRequestSchema, async () => {
      return {
        resources: APPS.map((app) => ({
          uri: `activecampaign://app/${app}`,
          mimeType: 'text/html',
          name: app
            .split('-')
            .map((w) => w.charAt(0).toUpperCase() + w.slice(1))
            .join(' '),
        })),
      };
    });

    // Read app resource
    this.server.setRequestHandler(ReadResourceRequestSchema, async (request) => {
      const uri = request.params.uri;
      const match = uri.match(/^activecampaign:\/\/app\/(.+)$/);

      if (!match) {
        throw new Error(`Invalid resource URI: ${uri}`);
      }

      const appName = match[1];
      if (!APPS.includes(appName)) {
        throw new Error(`Unknown app: ${appName}`);
      }

      try {
        // Dynamically import the app
        const appModule = await import(`./apps/${appName}/index.js`);
        const html = appModule.default();

        return {
          contents: [
            {
              uri,
              mimeType: 'text/html',
              text: html,
            },
          ],
        };
      } catch (error) {
        throw new Error(`Failed to load app ${appName}: ${error}`);
      }
    });
  }

  async connect(transport: any) {
    await this.server.connect(transport);
  }
}