// favorites_page exercises the per-page favorites listing API
// ([Client.FavoritesPage]) against the live FA site so a caller can see
// exactly what fields come back: HasNext, NextPage, len(Items), and a
// sample of the tag data lifted from each figure's data-tags attribute.
//
// Favorites pagination is cursor-based: each page returns an opaque
// NextPage token that addresses the next page. Pass it back in on the
// next call; treat empty as end-of-pagination.
//
// Required environment variables:
//
//	FA_A           — the `a` session cookie
//	FA_B           — the `b` session cookie
//	CF_CLEARANCE   — (optional) cf_clearance cookie if Cloudflare challenges
//	FA_UA          — (optional) User-Agent matching CF_CLEARANCE
//
// Usage:
//
//	go run ./examples/favorites_page <username> [maxPages]
package main

import (
	"context"
	"fmt"
	"log"
	"os"
	"strconv"

	fa "git.anthrove.art/public/go-fa-api"
)

func main() {
	if len(os.Args) < 2 {
		log.Fatalf("usage: %s <username> [maxPages]", os.Args[0])
	}
	user := os.Args[1]
	maxPages := 0
	if len(os.Args) >= 3 {
		if n, err := strconv.Atoi(os.Args[2]); err == nil && n > 0 {
			maxPages = n
		}
	}

	opts := []fa.Option{
		fa.WithCookies(fa.Cookies{A: os.Getenv("FA_A"), B: os.Getenv("FA_B")}),
	}
	if cf := os.Getenv("CF_CLEARANCE"); cf != "" {
		opts = append(opts, fa.WithCloudflare(fa.CFCookies{Clearance: cf}))
	}
	if ua := os.Getenv("FA_UA"); ua != "" {
		opts = append(opts, fa.WithUserAgent(ua))
	}
	client := fa.New(opts...)

	cursor := ""
	pageNum := 0
	for {
		pageNum++
		lp, err := client.FavoritesPage(context.Background(), user, cursor)
		if err != nil {
			log.Fatalf("FavoritesPage(cursor=%q): %v", cursor, err)
		}
		fmt.Printf("=== page %d  cursor=%q  items=%d  HasNext=%v  NextPage=%q ===\n",
			pageNum, cursor, len(lp.Items), lp.HasNext, lp.NextPage)
		for i, sub := range lp.Items {
			fmt.Printf("  [%d] id=%d  rating=%s  author=%s  title=%q\n",
				i, sub.ID, sub.Rating, sub.Author.Name, sub.Title)
		}
		if !lp.HasNext {
			fmt.Printf("\nreached end of pagination after %d page(s)\n", pageNum)
			return
		}
		if maxPages > 0 && pageNum >= maxPages {
			fmt.Printf("\nstopped at maxPages=%d (HasNext was still true; next cursor=%q)\n", maxPages, lp.NextPage)
			return
		}
		cursor = lp.NextPage
	}
}