package bkosmi

import (
	"context"
	"encoding/json"
	"fmt"
	"strings"
	"sync"
	"time"

	"github.com/chromedp/cdproto/input"
	"github.com/chromedp/cdproto/page"
	"github.com/chromedp/chromedp"
	"github.com/sirupsen/logrus"
)

// ChromeDPClient manages a headless Chrome instance to connect to Kosmi
type ChromeDPClient struct {
	ctx             context.Context
	cancel          context.CancelFunc
	roomURL         string
	log             *logrus.Entry
	messageHandlers []func(*NewMessagePayload)
	mu              sync.RWMutex
	connected       bool
}

// NewChromeDPClient creates a new ChromeDP-based Kosmi client
func NewChromeDPClient(roomURL string, log *logrus.Entry) *ChromeDPClient {
	return &ChromeDPClient{
		roomURL:         roomURL,
		log:             log,
		messageHandlers: []func(*NewMessagePayload){},
	}
}

// Connect launches Chrome and navigates to the Kosmi room
func (c *ChromeDPClient) Connect() error {
	c.log.Info("Launching headless Chrome for Kosmi connection")

	// Create Chrome context with flags to avoid headless detection
	opts := append(chromedp.DefaultExecAllocatorOptions[:],
		chromedp.Flag("headless", true),
		chromedp.Flag("disable-gpu", false), // Enable GPU to look more real
		chromedp.Flag("no-sandbox", true),
		chromedp.Flag("disable-dev-shm-usage", true),
		chromedp.Flag("disable-blink-features", "AutomationControlled"), // Hide automation
		chromedp.Flag("disable-infobars", true),
		chromedp.Flag("window-size", "1920,1080"),
		chromedp.UserAgent("Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36"),
	)

	allocCtx, allocCancel := chromedp.NewExecAllocator(context.Background(), opts...)
	ctx, cancel := chromedp.NewContext(allocCtx)

	c.ctx = ctx
	c.cancel = func() {
		cancel()
		allocCancel()
	}

	// Inject anti-detection scripts and WebSocket hook BEFORE any navigation
	c.log.Info("Injecting anti-detection and WebSocket interceptor...")
	if err := c.injectAntiDetection(); err != nil {
		return fmt.Errorf("failed to inject anti-detection: %w", err)
	}
	if err := c.injectWebSocketHookBeforeLoad(); err != nil {
		return fmt.Errorf("failed to inject WebSocket hook: %w", err)
	}

	// Now navigate to the room
	c.log.Infof("Navigating to Kosmi room: %s", c.roomURL)
	if err := chromedp.Run(ctx,
		chromedp.Navigate(c.roomURL),
		chromedp.WaitReady("body"),
	); err != nil {
		return fmt.Errorf("failed to navigate to room: %w", err)
	}

	c.log.Info("Page loaded, checking if hook is active...")
	
	// Verify the hook is installed
	var hookInstalled bool
	if err := chromedp.Run(ctx, chromedp.Evaluate(`window.__KOSMI_WS_HOOK_INSTALLED__ === true`, &hookInstalled)); err != nil {
		c.log.Warnf("Could not verify hook installation: %v", err)
	} else if hookInstalled {
		c.log.Info("✓ WebSocket hook confirmed installed")
	} else {
		c.log.Warn("✗ WebSocket hook not detected!")
	}
	
	// Wait a moment for WebSocket to connect
	c.log.Info("Waiting for WebSocket connection...")
	time.Sleep(3 * time.Second)
	
	// Check if we've captured any WebSocket connections
	var wsConnected string
	checkScript := `
		(function() {
			if (window.__KOSMI_WS_CONNECTED__) {
				return 'WebSocket connection intercepted';
			}
			return 'No WebSocket connection detected yet';
		})();
	`
	if err := chromedp.Run(ctx, chromedp.Evaluate(checkScript, &wsConnected)); err == nil {
		c.log.Infof("Status: %s", wsConnected)
	}

	c.mu.Lock()
	c.connected = true
	c.mu.Unlock()

	c.log.Info("Successfully connected to Kosmi via Chrome")

	// Start console log listener (for debugging)
	go c.listenToConsole()

	// Start message listener
	go c.listenForMessages()

	return nil
}

// injectAntiDetection injects scripts to hide automation/headless detection
func (c *ChromeDPClient) injectAntiDetection() error {
	script := `
		// Override navigator.webdriver
		Object.defineProperty(navigator, 'webdriver', {
			get: () => false,
		});
		
		// Override plugins
		Object.defineProperty(navigator, 'plugins', {
			get: () => [1, 2, 3, 4, 5],
		});
		
		// Override languages
		Object.defineProperty(navigator, 'languages', {
			get: () => ['en-US', 'en'],
		});
		
		// Chrome runtime
		window.chrome = {
			runtime: {},
		};
		
		// Permissions
		const originalQuery = window.navigator.permissions.query;
		window.navigator.permissions.query = (parameters) => (
			parameters.name === 'notifications' ?
				Promise.resolve({ state: Notification.permission }) :
				originalQuery(parameters)
		);
		
		console.log('[Kosmi Bridge] Anti-detection scripts injected');
	`
	
	return chromedp.Run(c.ctx, chromedp.ActionFunc(func(ctx context.Context) error {
		_, err := page.AddScriptToEvaluateOnNewDocument(script).Do(ctx)
		return err
	}))
}

// injectWebSocketHookBeforeLoad uses CDP to inject script before any page scripts run
func (c *ChromeDPClient) injectWebSocketHookBeforeLoad() error {
	// Get the WebSocket hook script
	script := c.getWebSocketHookScript()
	
	// Use chromedp.ActionFunc to access the CDP directly
	return chromedp.Run(c.ctx, chromedp.ActionFunc(func(ctx context.Context) error {
		// Use Page.addScriptToEvaluateOnNewDocument to inject before page load
		// This is the proper way to inject scripts that run before page JavaScript
		_, err := page.AddScriptToEvaluateOnNewDocument(script).Do(ctx)
		return err
	}))
}

// getWebSocketHookScript returns the WebSocket interception script
func (c *ChromeDPClient) getWebSocketHookScript() string {
	return `
		(function() {
			if (window.__KOSMI_WS_HOOK_INSTALLED__) {
				console.log('[Kosmi Bridge] WebSocket hook already installed');
				return;
			}

			// Store original WebSocket constructor
			const OriginalWebSocket = window.WebSocket;

			// Store messages in a queue
			window.__KOSMI_MESSAGE_QUEUE__ = [];

			// Hook WebSocket constructor
			window.WebSocket = function(url, protocols) {
				const socket = new OriginalWebSocket(url, protocols);
				
				// Check if this is Kosmi's GraphQL WebSocket
				if (url.includes('engine.kosmi.io') || url.includes('gql-ws')) {
					console.log('[Kosmi Bridge] WebSocket hook active for:', url);
					window.__KOSMI_WS_CONNECTED__ = true;
					
					// Method 1: Hook addEventListener
					const originalAddEventListener = socket.addEventListener.bind(socket);
					socket.addEventListener = function(type, listener, options) {
						if (type === 'message') {
							const wrappedListener = function(event) {
								try {
									const data = JSON.parse(event.data);
									console.log('[Kosmi Bridge] Message intercepted:', data);
									window.__KOSMI_MESSAGE_QUEUE__.push({
										timestamp: Date.now(),
										data: data,
										source: 'addEventListener'
									});
								} catch (e) {
									// Not JSON, skip
								}
								
								// Call original listener
								return listener.call(this, event);
							};
							return originalAddEventListener(type, wrappedListener, options);
						}
						return originalAddEventListener(type, listener, options);
					};
					
					// Method 2: Intercept onmessage property setter
					let realOnMessage = null;
					const descriptor = Object.getOwnPropertyDescriptor(WebSocket.prototype, 'onmessage');
					
					Object.defineProperty(socket, 'onmessage', {
						get: function() {
							return realOnMessage;
						},
						set: function(handler) {
							realOnMessage = function(event) {
								try {
									const data = JSON.parse(event.data);
									console.log('[Kosmi Bridge] Message via onmessage:', data);
									window.__KOSMI_MESSAGE_QUEUE__.push({
										timestamp: Date.now(),
										data: data,
										source: 'onmessage'
									});
								} catch (e) {
									// Not JSON, skip
								}
								
								// ALWAYS call original handler
								if (handler) {
									handler.call(socket, event);
								}
							};
							
							// Set it on the underlying WebSocket
							if (descriptor && descriptor.set) {
								descriptor.set.call(socket, realOnMessage);
							}
						},
						configurable: true
					});
					
					console.log('[Kosmi Bridge] WebSocket hooks installed');
				}
				
				return socket;
			};

			// Preserve the original constructor properties
			window.WebSocket.prototype = OriginalWebSocket.prototype;
			window.WebSocket.CONNECTING = OriginalWebSocket.CONNECTING;
			window.WebSocket.OPEN = OriginalWebSocket.OPEN;
			window.WebSocket.CLOSING = OriginalWebSocket.CLOSING;
			window.WebSocket.CLOSED = OriginalWebSocket.CLOSED;

			window.__KOSMI_WS_HOOK_INSTALLED__ = true;
			console.log('[Kosmi Bridge] WebSocket hook installed successfully');
		})();
	`
}

// listenToConsole captures console logs from the browser
func (c *ChromeDPClient) listenToConsole() {
	ticker := time.NewTicker(1 * time.Second)
	defer ticker.Stop()

	for {
		select {
		case <-c.ctx.Done():
			return
		case <-ticker.C:
			var logs string
			script := `
				(function() {
					if (!window.__KOSMI_CONSOLE_LOGS__) {
						window.__KOSMI_CONSOLE_LOGS__ = [];
						const originalLog = console.log;
						const originalWarn = console.warn;
						const originalError = console.error;
						
						console.log = function(...args) {
							window.__KOSMI_CONSOLE_LOGS__.push({type: 'log', message: args.join(' ')});
							originalLog.apply(console, args);
						};
						console.warn = function(...args) {
							window.__KOSMI_CONSOLE_LOGS__.push({type: 'warn', message: args.join(' ')});
							originalWarn.apply(console, args);
						};
						console.error = function(...args) {
							window.__KOSMI_CONSOLE_LOGS__.push({type: 'error', message: args.join(' ')});
							originalError.apply(console, args);
						};
					}
					
					const logs = window.__KOSMI_CONSOLE_LOGS__;
					window.__KOSMI_CONSOLE_LOGS__ = [];
					return JSON.stringify(logs);
				})();
			`
			
			if err := chromedp.Run(c.ctx, chromedp.Evaluate(script, &logs)); err != nil {
				continue
			}
			
			if logs != "" && logs != "[]" {
				var logEntries []struct {
					Type    string `json:"type"`
					Message string `json:"message"`
				}
				if err := json.Unmarshal([]byte(logs), &logEntries); err == nil {
					for _, entry := range logEntries {
						// Only show Kosmi Bridge logs
						if strings.Contains(entry.Message, "[Kosmi Bridge]") {
							switch entry.Type {
							case "error":
								c.log.Errorf("Browser: %s", entry.Message)
							case "warn":
								c.log.Warnf("Browser: %s", entry.Message)
							default:
								c.log.Debugf("Browser: %s", entry.Message)
							}
						}
					}
				}
			}
		}
	}
}

// listenForMessages continuously polls for new messages from the queue
func (c *ChromeDPClient) listenForMessages() {
	c.log.Info("Starting message listener")
	ticker := time.NewTicker(500 * time.Millisecond) // Poll every 500ms
	defer ticker.Stop()

	for {
		select {
		case <-c.ctx.Done():
			c.log.Info("Message listener stopped")
			return
		case <-ticker.C:
			if err := c.pollMessages(); err != nil {
				c.log.Errorf("Error polling messages: %v", err)
			}
		}
	}
}

// pollMessages retrieves and processes messages from the queue
func (c *ChromeDPClient) pollMessages() error {
	var messagesJSON string

	// Get and clear the message queue
	script := `
		(function() {
			const messages = window.__KOSMI_MESSAGE_QUEUE__ || [];
			const count = messages.length;
			window.__KOSMI_MESSAGE_QUEUE__ = [];
			
			if (count > 0) {
				console.log('[Kosmi Bridge] Polling found', count, 'messages');
			}
			
			return JSON.stringify(messages);
		})();
	`

	if err := chromedp.Run(c.ctx, chromedp.Evaluate(script, &messagesJSON)); err != nil {
		return err
	}

	if messagesJSON == "" || messagesJSON == "[]" {
		return nil // No messages
	}

	c.log.Debugf("Retrieved %d bytes of message data", len(messagesJSON))

	// Parse messages
	var messages []struct {
		Timestamp int64           `json:"timestamp"`
		Data      json.RawMessage `json:"data"`
		Source    string          `json:"source"`
	}

	if err := json.Unmarshal([]byte(messagesJSON), &messages); err != nil {
		c.log.Errorf("Failed to parse messages JSON: %v", err)
		c.log.Debugf("Raw JSON: %s", messagesJSON)
		return fmt.Errorf("failed to parse messages: %w", err)
	}

	c.log.Infof("Processing %d messages from queue", len(messages))

	// Process each message
	for i, msg := range messages {
		c.log.Debugf("Processing message %d/%d from source: %s", i+1, len(messages), msg.Source)
		c.processMessage(msg.Data)
	}

	return nil
}

// processMessage handles a single GraphQL message
func (c *ChromeDPClient) processMessage(data json.RawMessage) {
	// Parse as GraphQL message
	var gqlMsg struct {
		Type    string          `json:"type"`
		Payload json.RawMessage `json:"payload"`
	}

	if err := json.Unmarshal(data, &gqlMsg); err != nil {
		c.log.Debugf("Failed to parse GraphQL message: %v", err)
		return
	}

	// Only process "next" or "data" type messages
	if gqlMsg.Type != "next" && gqlMsg.Type != "data" {
		return
	}

	// Parse the payload
	var payload NewMessagePayload
	if err := json.Unmarshal(gqlMsg.Payload, &payload); err != nil {
		c.log.Debugf("Failed to parse message payload: %v", err)
		return
	}

	// Check if this is a newMessage event
	if payload.Data.NewMessage.Body == "" {
		return // Not a message event
	}

	// Call all registered handlers
	c.mu.RLock()
	handlers := c.messageHandlers
	c.mu.RUnlock()

	for _, handler := range handlers {
		handler(&payload)
	}
}

// OnMessage registers a handler for incoming messages
func (c *ChromeDPClient) OnMessage(handler func(*NewMessagePayload)) {
	c.mu.Lock()
	defer c.mu.Unlock()
	c.messageHandlers = append(c.messageHandlers, handler)
}

// SendMessage sends a message to the Kosmi room
func (c *ChromeDPClient) SendMessage(text string) error {
	c.mu.RLock()
	if !c.connected {
		c.mu.RUnlock()
		return fmt.Errorf("not connected")
	}
	c.mu.RUnlock()

	// Wait for the chat input to be available (with timeout)
	// Kosmi uses a contenteditable div with role="textbox"
	var inputFound bool
	for i := 0; i < 50; i++ {
		// Simple check without string replacement issues
		checkScript := `
			(function() {
				const input = document.querySelector('div[role="textbox"][contenteditable="true"]');
				return input !== null;
			})();
		`
		
		if err := chromedp.Run(c.ctx, chromedp.Evaluate(checkScript, &inputFound)); err != nil {
			return fmt.Errorf("failed to check for chat input: %w", err)
		}
		
		if inputFound {
			c.log.Infof("Chat input found after %d attempts (%.1f seconds)", i, float64(i)*0.1)
			break
		}
		
		// Log progress periodically
		if i == 0 || i == 10 || i == 25 || i == 49 {
			c.log.Debugf("Still waiting for chat input... attempt %d/50", i+1)
		}
		
		time.Sleep(100 * time.Millisecond)
	}
	
	if !inputFound {
		// Diagnostic: Get element counts directly
		var diagInfo struct {
			Textareas      int `json:"textareas"`
			Contenteditable int `json:"contenteditable"`
			Textboxes      int `json:"textboxes"`
		}
		
		diagScript := `
			(function() {
				return {
					textareas: document.querySelectorAll('textarea').length,
					contenteditable: document.querySelectorAll('[contenteditable="true"]').length,
					textboxes: document.querySelectorAll('[role="textbox"]').length
				};
			})();
		`
		
		if err := chromedp.Run(c.ctx, chromedp.Evaluate(diagScript, &diagInfo)); err == nil {
			c.log.Errorf("Diagnostic: textareas=%d, contenteditable=%d, textboxes=%d", 
				diagInfo.Textareas, diagInfo.Contenteditable, diagInfo.Textboxes)
		}
		
		c.log.Error("Chat input not found after 5 seconds")
		return fmt.Errorf("chat input not available after timeout")
	}

	// Send the message using ChromeDP's native SendKeys
	// This is more reliable than dispatching events manually and mimics actual user input
	selector := `div[role="textbox"][contenteditable="true"]`
	
	// First, clear the input and type the message
	err := chromedp.Run(c.ctx,
		chromedp.Focus(selector),
		chromedp.Evaluate(`document.querySelector('div[role="textbox"][contenteditable="true"]').textContent = ''`, nil),
		chromedp.SendKeys(selector, text),
	)
	
	if err != nil {
		return fmt.Errorf("failed to type message: %w", err)
	}
	
	// Small delay for React to process
	time.Sleep(100 * time.Millisecond)
	
	// Send Enter key using CDP Input API directly
	// This is closer to what Playwright does and should trigger all the right events
	err = chromedp.Run(c.ctx,
		chromedp.ActionFunc(func(ctx context.Context) error {
			// Send keyDown for Enter
			if err := input.DispatchKeyEvent(input.KeyDown).
				WithKey("Enter").
				WithCode("Enter").
				WithNativeVirtualKeyCode(13).
				WithWindowsVirtualKeyCode(13).
				Do(ctx); err != nil {
				return err
			}
			
			// Send keyUp for Enter
			return input.DispatchKeyEvent(input.KeyUp).
				WithKey("Enter").
				WithCode("Enter").
				WithNativeVirtualKeyCode(13).
				WithWindowsVirtualKeyCode(13).
				Do(ctx)
		}),
	)
	
	if err != nil {
		return fmt.Errorf("failed to send message via SendKeys: %w", err)
	}

	c.log.Debugf("Sent message: %s", text)
	return nil
}

// Close closes the Chrome instance
func (c *ChromeDPClient) Close() error {
	c.log.Info("Closing ChromeDP client")

	c.mu.Lock()
	c.connected = false
	c.mu.Unlock()

	if c.cancel != nil {
		c.cancel()
	}

	return nil
}

// IsConnected returns whether the client is connected
func (c *ChromeDPClient) IsConnected() bool {
	c.mu.RLock()
	defer c.mu.RUnlock()
	return c.connected
}

// escapeJSString escapes a string for use in JavaScript
func escapeJSString(s string) string {
	b, _ := json.Marshal(s)
	return string(b)
}