package browser

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"time"

	"github.com/chromedp/chromedp"

	"git.davoryn.de/calic/claude-statusline/internal/config"
)

// FetchViaChrome navigates to a URL using headless Chrome with the persistent
// browser profile (which has Cloudflare clearance cookies) and returns the
// response body. This bypasses Cloudflare JS challenges because Chrome runs
// real JavaScript. Falls back to non-headless if headless fails.
func FetchViaChrome(url string) ([]byte, error) {
	profileDir := filepath.Join(config.ConfigDir(), "browser-profile")
	if err := os.MkdirAll(profileDir, 0o755); err != nil {
		return nil, fmt.Errorf("create browser profile dir: %w", err)
	}

	// Remove stale lock file from unclean shutdown
	_ = os.Remove(filepath.Join(profileDir, "SingletonLock"))

	execPath := findBrowserExec()

	opts := append(chromedp.DefaultExecAllocatorOptions[:],
		chromedp.Flag("headless", true),
		chromedp.UserDataDir(profileDir),
	)
	if execPath != "" {
		opts = append(opts, chromedp.ExecPath(execPath))
	}

	allocCtx, allocCancel := chromedp.NewExecAllocator(context.Background(), opts...)
	defer allocCancel()

	ctx, cancel := chromedp.NewContext(allocCtx)
	defer cancel()

	// Set a total timeout for the operation
	ctx, timeoutCancel := context.WithTimeout(ctx, 30*time.Second)
	defer timeoutCancel()

	var body string
	err := chromedp.Run(ctx,
		chromedp.Navigate(url),
		// Wait for the body to have content (Cloudflare challenge resolves via JS)
		chromedp.WaitReady("body"),
		// Chrome renders JSON API responses inside a <pre> tag
		chromedp.Text("pre", &body, chromedp.ByQuery, chromedp.NodeVisible),
	)
	if err != nil {
		// Fallback: try extracting from body directly (some responses may not use <pre>)
		var bodyFallback string
		errFb := chromedp.Run(ctx,
			chromedp.Text("body", &bodyFallback, chromedp.ByQuery),
		)
		if errFb == nil && bodyFallback != "" {
			return []byte(bodyFallback), nil
		}
		return nil, fmt.Errorf("chromedp fetch: %w", err)
	}

	if body == "" {
		return nil, fmt.Errorf("chromedp fetch: empty response body")
	}

	// Gracefully close to flush cookies (including refreshed cf_clearance)
	cancel()

	return []byte(body), nil
}