package bot

import (
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"time"
)

// SteamFreeConfig is the config shape for bot_type "steamfree".
type SteamFreeConfig struct {
	ChannelID   string `json:"channel_id"`
	PollMinutes int    `json:"poll_minutes"`
}

// SteamFreeBot polls Steam's featured categories for 100%-off games.
func SteamFreeBot(ctx context.Context, _ *sql.DB, raw json.RawMessage, send SendMessageFunc) {
	var cfg SteamFreeConfig
	if err := json.Unmarshal(raw, &cfg); err != nil || cfg.ChannelID == "" {
		return
	}
	if cfg.PollMinutes <= 0 {
		cfg.PollMinutes = 30
	}

	seen := map[int]bool{}
	ticker := time.NewTicker(time.Duration(cfg.PollMinutes) * time.Minute)
	defer ticker.Stop()

	// Poll immediately on start
	pollSteam(cfg.ChannelID, seen, send)

	for {
		select {
		case <-ctx.Done():
			return
		case <-ticker.C:
			pollSteam(cfg.ChannelID, seen, send)
		}
	}
}

func pollSteam(channelID string, seen map[int]bool, send SendMessageFunc) {
	games, err := fetchFreeGames()
	if err != nil {
		return // ponytail: silent on error, logs add noise
	}
	for _, g := range games {
		if seen[g.ID] {
			continue
		}
		seen[g.ID] = true

		msg := fmt.Sprintf(
			"🎮 **FREE ON STEAM** 🎮\n**%s**\n~~$%.2f~~ → **FREE**\nhttps://store.steampowered.com/app/%d",
			g.Name, float64(g.OriginalPrice)/100, g.ID,
		)
		send(channelID, msg)
		time.Sleep(500 * time.Millisecond)
	}
}

type featuredCategories struct {
	Specials struct {
		Items []struct {
			ID            int    `json:"id"`
			Name          string `json:"name"`
			DiscountPct   int    `json:"discount_percent"`
			FinalPrice    int    `json:"final_price"`
			OriginalPrice int    `json:"original_price"`
		} `json:"items"`
	} `json:"specials"`
}

func fetchFreeGames() ([]struct {
	ID            int    `json:"id"`
	Name          string `json:"name"`
	DiscountPct   int    `json:"discount_percent"`
	FinalPrice    int    `json:"final_price"`
	OriginalPrice int    `json:"original_price"`
}, error) {
	client := &http.Client{Timeout: 15 * time.Second}
	resp, err := client.Get("https://store.steampowered.com/api/featuredcategories?cc=us&l=english")
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	if resp.StatusCode != 200 {
		return nil, fmt.Errorf("steam: %d", resp.StatusCode)
	}
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}
	var cats featuredCategories
	if err := json.Unmarshal(body, &cats); err != nil {
		return nil, err
	}
	var free []struct {
		ID            int    `json:"id"`
		Name          string `json:"name"`
		DiscountPct   int    `json:"discount_percent"`
		FinalPrice    int    `json:"final_price"`
		OriginalPrice int    `json:"original_price"`
	}
	for _, item := range cats.Specials.Items {
		if item.DiscountPct == 100 && item.OriginalPrice > 0 {
			free = append(free, item)
		}
	}
	return free, nil
}