package crawler

import (
	"context"
	"strings"
	"time"

	"github.com/chromedp/chromedp"
)

// DynamicCrawler chromedp 动态爬取
type DynamicCrawler struct{}

// NewDynamicCrawler 创建 DynamicCrawler
func NewDynamicCrawler() *DynamicCrawler { return &DynamicCrawler{} }

// Crawl 用无头浏览器爬取（用于 JS 渲染的页面）
func (c *DynamicCrawler) Crawl(ctx context.Context, targetURL string) *CrawlResult {
	result := &CrawlResult{}

	// 创建 chromedp allocator context，最多等待 30s
	allocCtx, cancel := chromedp.NewExecAllocator(ctx,
		chromedp.Headless,
		chromedp.DisableGPU,
		chromedp.NoSandbox,
		chromedp.Flag("disable-web-security", true),
	)
	defer cancel()

	taskCtx, taskCancel := context.WithTimeout(allocCtx, 30*time.Second)
	defer taskCancel()

	chromeCtx, chromeCancel := chromedp.NewContext(taskCtx)
	defer chromeCancel()

	var html string
	var links []interface{}

	err := chromedp.Run(chromeCtx,
		chromedp.Navigate(targetURL),
		chromedp.Sleep(3*time.Second), // 等待 JS 渲染
		chromedp.OuterHTML("html", &html),
		chromedp.Evaluate(`Array.from(document.querySelectorAll('a[href]')).map(a => a.href)`, &links),
	)

	if err != nil {
		result.Error = err
		return result
	}

	result.HTML = html

	// 将 interface{} 切片转为字符串切片
	for _, item := range links {
		link, ok := item.(string)
		if !ok {
			continue
		}
		result.Links = append(result.Links, link)
		if strings.Contains(link, "t.me/") || strings.Contains(link, "telegram.me/") {
			result.TgLinks = append(result.TgLinks, link)
		}
	}

	return result
}