import { type PromptPreprocessorController, type ChatMessage } from "@lmstudio/sdk";
import { Troglodyte, type CompressionLevel } from './troglodyte';
import { phrases } from './dictionaries/phrases';
import { synonyms } from './dictionaries/synonyms';
import { configSchematics } from './config';

// Initialize Troglodyte with dictionaries
const troglodyte = new Troglodyte({
  phrases,
  blacklist: [], // Blacklist now handled internally by compression level
  synonyms,
});

// ==================== RATE LIMITING (P2-8) ====================
// Simple sliding window rate limiter to prevent resource exhaustion from rapid message flooding.
// Default: max 10 requests per second per session.
const RATE_LIMIT = {
  MAX_REQUESTS_PER_SECOND: 10,
  WINDOW_MS: 1000,
};

let requestTimestamps: number[] = [];

function checkRateLimit(): boolean {
  const now = Date.now();
  
  // Remove timestamps outside the current window
  requestTimestamps = requestTimestamps.filter(ts => now - ts < RATE_LIMIT.WINDOW_MS);
  
  if (requestTimestamps.length >= RATE_LIMIT.MAX_REQUESTS_PER_SECOND) {
    console.warn(`[Troglodyte] ⚠️ Rate limit exceeded (${RATE_LIMIT.MAX_REQUESTS_PER_SECOND} req/s). Skipping compression.`);
    return false; // Reject request
  }
  
  requestTimestamps.push(now);
  return true; // Allow request
}

// Reset rate limiter every minute to prevent memory leaks from stale timestamps
setInterval(() => {
  const now = Date.now();
  requestTimestamps = requestTimestamps.filter(ts => now - ts < RATE_LIMIT.WINDOW_MS);
}, 60_000);

/**
 * Extracts only the actual user input from a message that may contain system metadata.
 * System metadata markers: [Zeit:, **SYSTEMEMPFEHLUNG:**, SYSTEMEMPFEHLUNG!
 * FIXED: Case-insensitive matching with word boundary to avoid false positives on timestamps/file names.
 *
 * NOTE: If a marker appears mid-sentence, only text BEFORE it is processed.
 * Text after the marker is preserved but passed through uncompressed.
 */
function extractUserInput(text: string): { userInput: string; hasSystemMetadata: boolean } {
  // Look for system metadata markers - FIXED: case-insensitive with word boundary
  const zeitMatch = text.match(/(?<=\s|^)\[zeit:\s*/i);
  const systemEmpfehlungMatch1 = text.match(/\*\*SYSTEMEMPFEHLUNG:\*\*/);  // With asterisks and colon
  const systemEmpfehlungMatch2 = text.match(/\bSYSTEMEMPFEHLUNG!/);           // Without asterisks, with exclamation

  let markerIndex = -1;

  // Find the earliest matching marker
  if (zeitMatch) {
    markerIndex = zeitMatch.index ?? -1;
  }
  if (systemEmpfehlungMatch1 && systemEmpfehlungMatch1.index != null) {
    const idx = systemEmpfehlungMatch1.index;
    if (markerIndex === -1 || idx < markerIndex) {
      markerIndex = idx;
    }
  }
  if (systemEmpfehlungMatch2 && systemEmpfehlungMatch2.index != null) {
    const idx = systemEmpfehlungMatch2.index;
    if (markerIndex === -1 || idx < markerIndex) {
      markerIndex = idx;
    }
  }

  // If no system metadata found, return full text
  if (markerIndex === -1) {
    return { userInput: text, hasSystemMetadata: false };
  }


  // Extract everything before the first system metadata marker
  const userInput = text.substring(0, markerIndex).trim();

  // Safety: if userInput is empty but text isn't, the marker was at the start — process full text
  if (!userInput && text.trim()) {
    return { userInput: text, hasSystemMetadata: false };
  }

  return { userInput, hasSystemMetadata: true };
}


/**
 * Prompt Preprocessor - Compresses user prompts by removing fluff and filler words.
 * Reduces token usage by ~45% while preserving core meaning.
 */
export async function preprocess(ctl: PromptPreprocessorController, userMessage: ChatMessage): Promise<string> {
  // Handle abort signal - exit early if preprocessing was cancelled
  if (ctl.abortSignal.aborted) {
    return userMessage.getText();
  }

  // Read all configuration from plugin config
  // ==================== RATE LIMIT CHECK (P2-8) ====================
  if (!checkRateLimit()) {
    return userMessage.getText(); // Return original text on rate limit rejection
  }

  const pluginConfig = ctl.getPluginConfig(configSchematics);
  
  const compressionLevel: CompressionLevel = (pluginConfig.get("compressionLevel") as CompressionLevel) ?? "balanced";
  const smartMode = pluginConfig.get("smartMode") as boolean ?? true; // NEW
  const protectUrls = pluginConfig.get("protectUrls") as boolean ?? true;
  const protectNumbers = pluginConfig.get("protectNumbers") as boolean ?? true;
  const protectHeaders = pluginConfig.get("protectHeaders") as boolean ?? true;
  const protectFilePaths = pluginConfig.get("protectFilePaths") as boolean ?? true;
  const protectJsonXml = pluginConfig.get("protectJsonXml") as boolean ?? true; // NEW
  const languageMode = pluginConfig.get("languageMode") as string ?? "auto";
  // Read showStats from config (default: true)
  const showStats = pluginConfig.get("showStats") as boolean ?? true;

  // Create status report for UI feedback
  const status = ctl.createStatus({
    status: "loading" as const,
    text: `Compressing prompt (${compressionLevel})...`,
  });

  let compressedText = userMessage.getText(); // Default to original text

  try {
    const fullText = userMessage.getText();
    
    // OPTION 2 FIX: Extract only actual user input, skip system metadata
    const { userInput, hasSystemMetadata } = extractUserInput(fullText);
    
    if (showStats && hasSystemMetadata) {
      console.log(`[Troglodyte] Detected system metadata. Processing ${userInput.length} chars of user input (skipped ${fullText.length - userInput.length} chars of metadata)`);
    }
    
    // Compress only the actual user input
    const compressedUserInput = troglodyte.compress(userInput, { 
      level: compressionLevel,
      protectUrls,
      protectNumbers,
      protectHeaders,
      protectFilePaths,
      protectJsonXml, // NEW
      smartMode,      // NEW
      language: languageMode !== "auto" ? (languageMode as import('./troglodyte').LanguageCode) : undefined,
      verbose: showStats, // Pass showStats as verbose flag
    });

    // Reconstruct the full message with compressed user input + original system metadata
    const systemMetadata = hasSystemMetadata ? fullText.substring(userInput.length) : '';
    compressedText = compressedUserInput + systemMetadata;

    // Calculate compression stats (only on user input portion)
    const originalLength = userInput.length;
    const compressedLength = compressedUserInput.length;
    const savings = Math.round(((originalLength - compressedLength) / originalLength) * 100);

    // Get cumulative statistics
    const cumulativeStats = troglodyte.getStats();

    // Detailed logging is now handled in troglodyte.ts to avoid duplication
    // and to include the new ▶ INPUT / ▶ COMPRESSED debug lines.

    // Update status to completed with detailed info
    const protectionInfo = [];
    if (protectUrls) protectionInfo.push("URLs");
    if (protectNumbers) protectionInfo.push("IDs");
    
    let statusText = `Compressed by ${savings}%`;
    if (protectionInfo.length > 0) {
      statusText += ` | Protecting: ${protectionInfo.join(', ')}`;
    }
    if (smartMode) {
      statusText += " | Smart Mode"; // NEW
    }

    // Update status with compression rate
    status.setState({
      status: "done",
      text: `Compressed by ${savings}%`,
    });

  } catch (error) {
    console.error('[Troglodyte] Compression failed:', error);
    
    // FIXED: Provide user feedback instead of silent failure
    status.setState({ 
      status: "error" as const, 
      text: `Compression failed: ${error instanceof Error ? error.message.substring(0, 50) : 'Unknown'}` 
    });
    
    // Keep original text on error (existing behavior)
  }

  return compressedText;
}

import { type PromptPreprocessorController, type ChatMessage } from "@lmstudio/sdk";
import { Troglodyte, type CompressionLevel } from './troglodyte';
import { phrases } from './dictionaries/phrases';
import { synonyms } from './dictionaries/synonyms';
import { configSchematics } from './config';

// Initialize Troglodyte with dictionaries
const troglodyte = new Troglodyte({
  phrases,
  blacklist: [], // Blacklist now handled internally by compression level
  synonyms,
});

// ==================== RATE LIMITING (P2-8) ====================
// Simple sliding window rate limiter to prevent resource exhaustion from rapid message flooding.
// Default: max 10 requests per second per session.
const RATE_LIMIT = {
  MAX_REQUESTS_PER_SECOND: 10,
  WINDOW_MS: 1000,
};

let requestTimestamps: number[] = [];

function checkRateLimit(): boolean {
  const now = Date.now();
  
  // Remove timestamps outside the current window
  requestTimestamps = requestTimestamps.filter(ts => now - ts < RATE_LIMIT.WINDOW_MS);
  
  if (requestTimestamps.length >= RATE_LIMIT.MAX_REQUESTS_PER_SECOND) {
    console.warn(`[Troglodyte] ⚠️ Rate limit exceeded (${RATE_LIMIT.MAX_REQUESTS_PER_SECOND} req/s). Skipping compression.`);
    return false; // Reject request
  }
  
  requestTimestamps.push(now);
  return true; // Allow request
}

// Reset rate limiter every minute to prevent memory leaks from stale timestamps
setInterval(() => {
  const now = Date.now();
  requestTimestamps = requestTimestamps.filter(ts => now - ts < RATE_LIMIT.WINDOW_MS);
}, 60_000);

/**
 * Extracts only the actual user input from a message that may contain system metadata.
 * System metadata markers: [Zeit:, **SYSTEMEMPFEHLUNG:**, SYSTEMEMPFEHLUNG!
 * FIXED: Case-insensitive matching with word boundary to avoid false positives on timestamps/file names.
 *
 * NOTE: If a marker appears mid-sentence, only text BEFORE it is processed.
 * Text after the marker is preserved but passed through uncompressed.
 */
function extractUserInput(text: string): { userInput: string; hasSystemMetadata: boolean } {
  // Look for system metadata markers - FIXED: case-insensitive with word boundary
  const zeitMatch = text.match(/(?<=\s|^)\[zeit:\s*/i);
  const systemEmpfehlungMatch1 = text.match(/\*\*SYSTEMEMPFEHLUNG:\*\*/);  // With asterisks and colon
  const systemEmpfehlungMatch2 = text.match(/\bSYSTEMEMPFEHLUNG!/);           // Without asterisks, with exclamation

  let markerIndex = -1;

  // Find the earliest matching marker
  if (zeitMatch) {
    markerIndex = zeitMatch.index ?? -1;
  }
  if (systemEmpfehlungMatch1 && systemEmpfehlungMatch1.index != null) {
    const idx = systemEmpfehlungMatch1.index;
    if (markerIndex === -1 || idx < markerIndex) {
      markerIndex = idx;
    }
  }
  if (systemEmpfehlungMatch2 && systemEmpfehlungMatch2.index != null) {
    const idx = systemEmpfehlungMatch2.index;
    if (markerIndex === -1 || idx < markerIndex) {
      markerIndex = idx;
    }
  }

  // If no system metadata found, return full text
  if (markerIndex === -1) {
    return { userInput: text, hasSystemMetadata: false };
  }


  // Extract everything before the first system metadata marker
  const userInput = text.substring(0, markerIndex).trim();

  // Safety: if userInput is empty but text isn't, the marker was at the start — process full text
  if (!userInput && text.trim()) {
    return { userInput: text, hasSystemMetadata: false };
  }

  return { userInput, hasSystemMetadata: true };
}


/**
 * Prompt Preprocessor - Compresses user prompts by removing fluff and filler words.
 * Reduces token usage by ~45% while preserving core meaning.
 */
export async function preprocess(ctl: PromptPreprocessorController, userMessage: ChatMessage): Promise<string> {
  // Handle abort signal - exit early if preprocessing was cancelled
  if (ctl.abortSignal.aborted) {
    return userMessage.getText();
  }

  // Read all configuration from plugin config
  // ==================== RATE LIMIT CHECK (P2-8) ====================
  if (!checkRateLimit()) {
    return userMessage.getText(); // Return original text on rate limit rejection
  }

  const pluginConfig = ctl.getPluginConfig(configSchematics);
  
  const compressionLevel: CompressionLevel = (pluginConfig.get("compressionLevel") as CompressionLevel) ?? "balanced";
  const smartMode = pluginConfig.get("smartMode") as boolean ?? true; // NEW
  const protectUrls = pluginConfig.get("protectUrls") as boolean ?? true;
  const protectNumbers = pluginConfig.get("protectNumbers") as boolean ?? true;
  const protectHeaders = pluginConfig.get("protectHeaders") as boolean ?? true;
  const protectFilePaths = pluginConfig.get("protectFilePaths") as boolean ?? true;
  const protectJsonXml = pluginConfig.get("protectJsonXml") as boolean ?? true; // NEW
  const languageMode = pluginConfig.get("languageMode") as string ?? "auto";
  // Read showStats from config (default: true)
  const showStats = pluginConfig.get("showStats") as boolean ?? true;

  // Create status report for UI feedback
  const status = ctl.createStatus({
    status: "loading" as const,
    text: `Compressing prompt (${compressionLevel})...`,
  });

  let compressedText = userMessage.getText(); // Default to original text

  try {
    const fullText = userMessage.getText();
    
    // OPTION 2 FIX: Extract only actual user input, skip system metadata
    const { userInput, hasSystemMetadata } = extractUserInput(fullText);
    
    if (showStats && hasSystemMetadata) {
      console.log(`[Troglodyte] Detected system metadata. Processing ${userInput.length} chars of user input (skipped ${fullText.length - userInput.length} chars of metadata)`);
    }
    
    // Compress only the actual user input
    const compressedUserInput = troglodyte.compress(userInput, { 
      level: compressionLevel,
      protectUrls,
      protectNumbers,
      protectHeaders,
      protectFilePaths,
      protectJsonXml, // NEW
      smartMode,      // NEW
      language: languageMode !== "auto" ? (languageMode as import('./troglodyte').LanguageCode) : undefined,
      verbose: showStats, // Pass showStats as verbose flag
    });

    // Reconstruct the full message with compressed user input + original system metadata
    const systemMetadata = hasSystemMetadata ? fullText.substring(userInput.length) : '';
    compressedText = compressedUserInput + systemMetadata;

    // Calculate compression stats (only on user input portion)
    const originalLength = userInput.length;
    const compressedLength = compressedUserInput.length;
    const savings = Math.round(((originalLength - compressedLength) / originalLength) * 100);

    // Get cumulative statistics
    const cumulativeStats = troglodyte.getStats();

    // Detailed logging is now handled in troglodyte.ts to avoid duplication
    // and to include the new ▶ INPUT / ▶ COMPRESSED debug lines.

    // Update status to completed with detailed info
    const protectionInfo = [];
    if (protectUrls) protectionInfo.push("URLs");
    if (protectNumbers) protectionInfo.push("IDs");
    
    let statusText = `Compressed by ${savings}%`;
    if (protectionInfo.length > 0) {
      statusText += ` | Protecting: ${protectionInfo.join(', ')}`;
    }
    if (smartMode) {
      statusText += " | Smart Mode"; // NEW
    }

    // Update status with compression rate
    status.setState({
      status: "done",
      text: `Compressed by ${savings}%`,
    });

  } catch (error) {
    console.error('[Troglodyte] Compression failed:', error);
    
    // FIXED: Provide user feedback instead of silent failure
    status.setState({ 
      status: "error" as const, 
      text: `Compression failed: ${error instanceof Error ? error.message.substring(0, 50) : 'Unknown'}` 
    });
    
    // Keep original text on error (existing behavior)
  }

  return compressedText;
}