package main

import (
	"context"
	"fmt"
	"time"

	"github.com/chromedp/chromedp"
)

// GetToken retrieves a Kosmi authentication token.
// Priority: manual > email/password > error
func GetToken(manual string, email string, password string) (string, error) {
	// If manual token provided, use it immediately
	if manual != "" {
		return manual, nil
	}

	// If email and password provided, attempt chromedp login
	if email != "" && password != "" {
		return loginWithChromedp(email, password)
	}

	// No authentication method provided
	return "", fmt.Errorf("no authentication method provided: use --token or --email/--password")
}

// loginWithChromedp uses browser automation to log in and extract the JWT token.
func loginWithChromedp(email, password string) (string, error) {
	// Create context with timeout
	ctx, cancel := context.WithTimeout(context.Background(), 90*time.Second)
	defer cancel()

	// Set up chromedp options (headless mode)
	opts := []chromedp.ExecAllocatorOption{
		chromedp.NoFirstRun,
		chromedp.NoDefaultBrowserCheck,
		chromedp.DisableGPU,
		chromedp.NoSandbox,
		chromedp.Headless,
	}

	// Create allocator context
	allocCtx, cancel := chromedp.NewExecAllocator(ctx, opts...)
	defer cancel()

	// Create browser context with no logging to suppress cookie errors
	ctx, cancel = chromedp.NewContext(allocCtx, chromedp.WithLogf(func(string, ...interface{}) {}))
	defer cancel()

	var token string

	// Run the automation tasks
	err := chromedp.Run(ctx,
		// Navigate to Kosmi
		chromedp.Navigate("https://app.kosmi.io"),
		chromedp.WaitReady("body"),
		chromedp.Sleep(3*time.Second),
		
		// Find and click Login button
		chromedp.ActionFunc(func(ctx context.Context) error {
			var found bool
			if err := chromedp.Evaluate(`
				(() => {
					const buttons = Array.from(document.querySelectorAll('button'));
					const btn = buttons.find(el => {
						const text = el.textContent.trim();
						return text === 'Login' || text === 'Log in';
					});
					if (btn) {
						btn.click();
						return true;
					}
					return false;
				})()
			`, &found).Do(ctx); err != nil {
				return err
			}
			if !found {
				return fmt.Errorf("Login button not found")
			}
			return nil
		}),
		
		// Wait and click "Login with Email"
		chromedp.Sleep(3*time.Second),
		chromedp.ActionFunc(func(ctx context.Context) error {
			var found bool
			if err := chromedp.Evaluate(`
				(() => {
					const btn = Array.from(document.querySelectorAll('button')).find(el => 
						el.textContent.includes('Email')
					);
					if (btn) {
						btn.click();
						return true;
					}
					return false;
				})()
			`, &found).Do(ctx); err != nil {
				return err
			}
			if !found {
				return fmt.Errorf("'Login with Email' button not found")
			}
			return nil
		}),
		
		// Wait for form and fill credentials
		chromedp.Sleep(3*time.Second),
		chromedp.WaitVisible(`input[type="password"]`, chromedp.ByQuery),
		chromedp.Click(`input[placeholder*="Email"], input[placeholder*="Username"]`, chromedp.ByQuery),
		chromedp.Sleep(200*time.Millisecond),
		chromedp.SendKeys(`input[placeholder*="Email"], input[placeholder*="Username"]`, email, chromedp.ByQuery),
		chromedp.Sleep(500*time.Millisecond),
		chromedp.Click(`input[type="password"]`, chromedp.ByQuery),
		chromedp.Sleep(200*time.Millisecond),
		chromedp.SendKeys(`input[type="password"]`, password+"\n", chromedp.ByQuery),
		chromedp.Sleep(500*time.Millisecond),
		
		// Wait for login to complete - check for modal to close
		chromedp.ActionFunc(func(ctx context.Context) error {
			// Wait for the login modal to disappear (indicates successful login)
			maxAttempts := 30 // 15 seconds total
			for i := 0; i < maxAttempts; i++ {
				time.Sleep(500 * time.Millisecond)
				
				// Check if login modal is gone (successful login)
				var modalGone bool
				chromedp.Evaluate(`
					(() => {
						// Check if the email/password form is still visible
						const emailInput = document.querySelector('input[placeholder*="Email"], input[placeholder*="Username"]');
						const passwordInput = document.querySelector('input[type="password"]');
						return !emailInput && !passwordInput;
					})()
				`, &modalGone).Do(ctx)
				
				if modalGone {
					// Modal is gone, wait a bit more for token to be set
					time.Sleep(2 * time.Second)
					chromedp.Evaluate(`localStorage.getItem('token')`, &token).Do(ctx)
					if token != "" {
						return nil
					}
				}
				
				// Check for error messages
				var errorText string
				chromedp.Evaluate(`
					(() => {
						const errorEl = document.querySelector('[role="alert"], .error, .error-message');
						return errorEl ? errorEl.textContent.trim() : '';
					})()
				`, &errorText).Do(ctx)
				
				if errorText != "" && errorText != "null" {
					return fmt.Errorf("login failed: %s", errorText)
				}
			}
			
			// Timeout - get whatever token is there
			chromedp.Evaluate(`localStorage.getItem('token')`, &token).Do(ctx)
			if token == "" {
				return fmt.Errorf("login timeout: no token found")
			}
			return nil
		}),
	)

	if err != nil {
		return "", fmt.Errorf("browser automation failed: %w", err)
	}

	if token == "" {
		return "", fmt.Errorf("failed to extract token from localStorage")
	}

	return token, nil
}