import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { z } from "zod";

// Get configuration from environment variables or command-line arguments
const getConfigValue = (name: string, fallback?: string): string | undefined => {
  // Check command line args first (format: --name=value)
  const commandArg = process.argv.find(arg => arg.startsWith(`--${name}=`));
  if (commandArg) {
    return commandArg.split('=')[1];
  }
  
  // Then check environment variables
  if (process.env[name] || process.env[name.toUpperCase()]) {
    return process.env[name] || process.env[name.toUpperCase()];
  }
  
  return fallback;
};

// Get configuration
const CLARITY_API_TOKEN = getConfigValue('clarity_api_token');

// Create server instance
const server = new McpServer({
  name: "@microsoft/clarity-mcp-server",
  version: "1.0.0",
  capabilities: {
    resources: {},
    tools: {},
  },
});

// Constants for API
const API_BASE_URL = "https://www.clarity.ms/export-data/api/v1/project-live-insights";

// Available metrics that may be returned by the API
const AVAILABLE_METRICS = [
  "ScrollDepth",
  "EngagementTime",
  "Traffic",
  "PopularPages",
  "Browser",
  "Device",
  "OS",
  "Country/Region",
  "PageTitle",
  "ReferrerURL",
  "DeadClickCount",
  "ExcessiveScroll",
  "RageClickCount",
  "QuickbackClick",
  "ScriptErrorCount",
  "ErrorClickCount"
];

// Available dimensions that can be used in queries
const AVAILABLE_DIMENSIONS = [
  "Browser",
  "Device",
  "Country/Region",
  "OS",
  "Source",
  "Medium",
  "Campaign",
  "Channel",
  "URL"
];

// Helper function to make API requests
async function fetchClarityData(
  token: string, 
  numOfDays: number, 
  dimensions: string[] = []
): Promise<any> {
  try {
    // Build parameters for the API request
    const params = new URLSearchParams();
    params.append("numOfDays", numOfDays.toString());
    
    // Add dimensions if specified (maximum 3 allowed)
    dimensions.slice(0, 3).forEach((dim, index) => {
      params.append(`dimension${index + 1}`, dim);
    });
    
    // Make the API request
    const url = `${API_BASE_URL}?${params.toString()}&src=mcp`;
    console.error(`Making request to: ${url}`);
    
    const response = await fetch(url, {
      method: 'GET',
      headers: {
        'Content-Type': 'application/json',
        'Authorization': `Bearer ${token}`
      }
    });

    if (!response.ok) {
      throw new Error(`API request failed with status ${response.status}`);
    }

    return await response.json();
  } catch (error) {
    console.error("Error fetching Clarity data:", error);
    return { error: error instanceof Error ? error.message : "Unknown error" };
  }
}

// Register the get-clarity-data tool
server.tool(
  "get-clarity-data",
  "Fetch Microsoft Clarity analytics data",
  {
    numOfDays: z.number().min(1).max(3).describe("Number of days to retrieve data for (1-3)"),
    dimensions: z.array(z.string()).optional().describe("Up to 3 dimensions to filter by (Browser, Device, Country/Region, OS, Source, Medium, Campaign, Channel, URL)"),
    metrics: z.array(z.string()).optional().describe("Metrics to retrieve (Scroll Depth, Engagement Time, Traffic, Popular Pages, Browser, Device, OS, Country/Region, etc.)"),
    token: z.string().optional().describe("Your Clarity API token (optional if provided via environment or command line)"),
  },
  async ({ numOfDays, dimensions = [], metrics = [], token }) => {
    // Use provided token or fallback to environment/command-line variables
    const finalToken = token || CLARITY_API_TOKEN;
    
    // Check if we have the necessary credentials
    if (!finalToken) {
      return {
        content: [
          {
            type: "text",
            text: "No Clarity API token provided. Please provide a token via the 'token' parameter, CLARITY_API_TOKEN environment variable, or --clarity_api_token command-line argument.",
          },
        ],
      };
    }

    // Validate dimensions against known valid dimensions
    const filteredDimensions = dimensions.filter(d => AVAILABLE_DIMENSIONS.includes(d));
    if (filteredDimensions.length < dimensions.length) {
      console.warn("Some dimensions were invalid and have been filtered out");
    }

    // Fetch data from Clarity API
    const data = await fetchClarityData(finalToken, numOfDays, filteredDimensions);

    // Check for errors
    if (data.error) {
      return {
        content: [
          {
            type: "text",
            text: `Error fetching data: ${data.error}`,
          },
        ],
      };
    }

    // Filter metrics if specified
    let formattedResult = data;
    if (metrics && metrics.length > 0) {
      // Filter the metrics if requested (case-insensitive match for user convenience)
      formattedResult = data.filter((item: any) => 
        metrics.some(m => 
          item.metricName.toLowerCase() === m.toLowerCase() ||
          item.metricName.replace(/\s+/g, '').toLowerCase() === m.replace(/\s+/g, '').toLowerCase()
        )
      );
    }

    const resultText = JSON.stringify(formattedResult, null, 2);

    return {
      content: [
        {
          type: "text",
          text: resultText,
        },
      ],
    };
  },
);

// Main function
async function main() {
  // Log configuration status
  if (CLARITY_API_TOKEN) {
    console.error("Clarity API token configured via environment/command-line");
  } else {
    console.error("No Clarity API token configured, it must be provided with each request");
  }

  console.error(`Supported metrics: ${AVAILABLE_METRICS.join(", ")}`);
  console.error(`Supported dimensions: ${AVAILABLE_DIMENSIONS.join(", ")}`);

  const transport = new StdioServerTransport();
  await server.connect(transport);
  console.error("Microsoft Clarity Data Export MCP Server running on stdio");
}

// Run the server
main().catch((error) => {
  console.error("Fatal error in main():", error);
  process.exit(1);
});