package parser

import (
	"context"
	"errors"
	"fmt"
	"io"
	"log/slog"
	"net/http"
	"net/url"
	"recipes/internal/domain/models"
	"recipes/internal/lib/stringcv"
	"strconv"
	"strings"
	"sync"

	"github.com/PuerkitoBio/goquery"
	"github.com/google/uuid"
	"github.com/s32x/httpclient"
)

const baseUrl string = "https://www.vsegdavkusno.ru"

var client *httpclient.Client = httpclient.New().WithBaseURL(baseUrl)

var PHPSESSID string
var parseKey string

var (
	KeyNotFoundErr      = errors.New("key not found")
	CookieNotFoundErr   = errors.New("cookie not found")
	NotSuccessReqErr    = errors.New("not success request")
	EmptyLinkErr        = errors.New("empty link")
	RecipeExistsErr     = errors.New("recipe already exists")
	FailUpdatePHPSESSID = errors.New("failed to update PHPSESSID")
	FailUpdateKEY       = errors.New("failed to update KEY")
)

type pictureSaver interface {
	SaveRecipeImage(ctx context.Context, imageFile io.Reader, filename string, contentType string, fileSize int64) error
}

type recipeSaver interface {
	AddRecipe(ctx context.Context, recipe models.Recipe) error
}

type recipeProvider interface {
	RecipeExists(ctx context.Context, title string) (bool, error)
}

// SaveAllPages saves all pages to storage.
func SaveAllPages(log *slog.Logger, ps pictureSaver, rs recipeSaver, rp recipeProvider) error {
	const op = "parser.SaveAllPages"
	// get total
	log.Debug("Сохраняю страницу 1...")
	total, err := SavePage(log, 1, ps, rs, rp)
	if err != nil {
		return fmt.Errorf("%s: %w", op, err)
	}
	fmt.Println("Total =", total)
	for i := 2; i <= total; i++ {
		log.Debug(fmt.Sprintf("Сохраняю страницу %d...\n", i))
		_, err = SavePage(log, i, ps, rs, rp)
		if err != nil {
			log.Error("Страница не сохранена", "err", fmt.Errorf("%s: %w", op, err))
			continue
		}
		log.Debug(fmt.Sprintf("Страница %d сохранена\n", i))
	}
	return nil
}

// SavePage saves page to storage.
func SavePage(log *slog.Logger, page int, ps pictureSaver, rs recipeSaver, rp recipeProvider) (int, error) {
	const op = "parser.SavePage"

	var resp GetPageResp
	var body io.Reader
	for i := 0; i <= 3; i++ {
		// make form
		form := make(url.Values)
		form.Add("page", fmt.Sprint(page))
		form.Add("action", "filter")
		form.Add("pageId", "7")
		form.Add("key", parseKey)
		// send request
		err := client.
			WithHeader("Cookie", fmt.Sprintf("PHPSESSID=%s", PHPSESSID)).
			WithHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8").
			Post("/assets/components/msearch2/action.php").WithForm(form).JSON(&resp)
		if err != nil {
			return 0, fmt.Errorf("%s: %w", op, err)
		}
		// update PHPSESSID and KEY
		if resp.Message == "Could not load config" {
			err = GetPHPSESSID(log)
			if err != nil {
				return 0, fmt.Errorf("%s: %w", op, FailUpdatePHPSESSID)
			}
			err = GetKey(log)
			if err != nil {
				return 0, fmt.Errorf("%s: %w", op, FailUpdateKEY)
			}
			continue
		}
		if !resp.Success {
			return 0, fmt.Errorf("%s: %w", op, NotSuccessReqErr)
		}
		body = strings.NewReader(resp.Data.Results)
		break
	}
	doc, err := goquery.NewDocumentFromReader(body)
	if err != nil {
		return 0, fmt.Errorf("%s: %w", op, err)
	}
	var recipes []models.Recipe
	doc.Find("div.recipe-card").Each(func(i int, s *goquery.Selection) {
		var recipe models.Recipe
		recipe.Title = s.Find("div.recipe-card__title").Text()
		// recipe.Time = strings.ReplaceAll(strings.ReplaceAll(s.Find("div.recipe-card__time").Text(), "\n", ""), "  ", "")
		recipe.Image, _ = s.Find("img").Attr("src")
		recipe.Image = strings.Replace(recipe.Image, "image_366", "image_732", 1)
		recipe.Image = fmt.Sprintf("%s%s", baseUrl, recipe.Image)
		recipe.Link, _ = s.Find("a.recipe-card__link").Attr("href")
		recipe.Link = fmt.Sprintf("/%s", recipe.Link)

		recipes = append(recipes, recipe)
	})

	var wg sync.WaitGroup
	wg.Add(len(recipes))
	for i := 0; i < len(recipes); i++ {
		go func(i int, log *slog.Logger) {
			defer wg.Done()
			err = GetRecipe(&recipes[i], ps, rs, rp)
			if err != nil {
				if errors.Is(err, RecipeExistsErr) {
					log.Warn("Recipe already exists")
					return
				}
				log.Error("Failed to get recipe", "err", fmt.Errorf("%s: %w", op, err))
			}
		}(i, log)
	}
	wg.Wait()
	return resp.Data.Pages, nil
}

// GetRecipe gets recipe info and saves recipe to storage.
func GetRecipe(r *models.Recipe, ps pictureSaver, rs recipeSaver, rp recipeProvider) error {
	const op = "parser.GetRecipe"

	if r.Link == "" {
		return fmt.Errorf("%s: %w", op, EmptyLinkErr)
	}
	// send request
	body, err := client.
		WithHeader("Cookie", fmt.Sprintf("PHPSESSID=%s", PHPSESSID)).
		Post(r.Link).String()
	if err != nil {
		return fmt.Errorf("%s: %w", op, err)
	}
	bodyr := strings.NewReader(body)
	doc, err := goquery.NewDocumentFromReader(bodyr)
	if err != nil {
		return fmt.Errorf("%s: %w", op, err)
	}
	// описание
	r.Description = strings.ReplaceAll(strings.ReplaceAll(strings.ReplaceAll(doc.Find("div.card-binfo__description").Text(), "  ", ""), "\n", ""), "\t", "")
	// Время готовки, кол-во порций
	doc.Find("div.recipe-summary-items>div.recipe-summary-item").Each(func(i int, s *goquery.Selection) {
		label := s.Find("div.recipe-summary-item__label").Text()
		value := strings.ReplaceAll(s.Find("div.recipe-summary-item__value").Text(), "\n", "")
		switch label {
		case "Время приготовления:":
			r.CookingTime = value
		case "Количество порций:":
			count, _ := strconv.Atoi(value)
			r.ServingsNum = uint(count)
		case "Калорийность:":
			r.Calories = value
		}
	})
	doc.Find("div.ingredients").Each(func(i int, s *goquery.Selection) {
		// ингридиенты для рецепта
		var ingredients models.RecipeIngredients
		ingredients.Title = s.Find("div.ingredients__title").Text()
		s.Find("ul.ingredients__list>li").Each(func(i int, q *goquery.Selection) {
			ingredient := strings.ReplaceAll(strings.ReplaceAll(q.Text(), "  ", ""), "\n", "")
			ingredients.Ingredients = append(ingredients.Ingredients, ingredient)
		})
		if len(ingredients.Ingredients) != 0 {
			r.Ingredients = append(r.Ingredients, ingredients)
		}
		// шаги рецепта
		var recipe_steps []string
		s.Find("div.recipe-rich>ol>li>span").Each(func(i int, q *goquery.Selection) {
			recipe_step := strings.ReplaceAll(strings.ReplaceAll(q.Text(), "  ", ""), "\n", "")
			recipe_steps = append(recipe_steps, recipe_step)
		})
		if len(recipe_steps) != 0 {
			r.Recipe_steps = recipe_steps
		}
		// рекомендации
		var advices []string
		s.Find("div.recipe-footer__additional-text>p").Each(func(i int, q *goquery.Selection) {
			if q.Find("br").Length() > 0 {
				html, _ := q.Html()
				// if err != nil {
				// 	return fmt.Errorf("%s: %w", op, err)
				// }
				advice_list := q.SetHtml(strings.Replace(html, "<br/>", "\n", -1)).Text()
				advices_arr := strings.Split(advice_list, "\n")
				var advices_arr_res []string = make([]string, 0, len(advices_arr))
				for _, a := range advices_arr {
					if a != "" {
						advices_arr_res = append(advices_arr_res, a)
					}
				}
				advices = append(advices, advices_arr_res...)
			} else {
				var advice string = q.Text()
				advices = append(advices, advice)
			}
		})
		if len(advices) != 0 {
			// fmt.Printf("LEN ADVICES = %d", len(advices))
			r.Advices = advices
		}
	})
	// категории
	doc.Find("div.similar-items>a.similar-items__link").Each(func(i int, s *goquery.Selection) {
		r.Categories = append(r.Categories, s.Text())
	})
	// check recipe exists
	ex, err := rp.RecipeExists(context.Background(), r.Title) // interface!
	if err != nil || ex {
		return fmt.Errorf("%s: %w", op, RecipeExistsErr)
	}
	// save picture
	err = SaveRecipePicture(r, ps)
	if err != nil {
		return fmt.Errorf("%s: %w", op, err)
	}
	// insert recipe
	err = rs.AddRecipe(context.Background(), *r)
	if err != nil {
		return fmt.Errorf("%s: %w", op, err)
	}
	return nil
}

func SaveRecipePicture(r *models.Recipe, ps pictureSaver) error {
	const op = "parser.SaveRecipePicture"

	resp, err := http.Get(r.Image)
	if err != nil {
		return fmt.Errorf("%s: %w", op, err)
	}
	defer resp.Body.Close()
	content_len, _ := strconv.ParseInt(resp.Header["Content-Length"][0], 10, 64)
	// change name to generated uuid
	filename := stringcv.RenameFile(stringcv.GetFilenameFromUrl(r.Image), uuid.NewString())
	// upload to storage
	err = ps.SaveRecipeImage(context.Background(), resp.Body, filename, resp.Header["Content-Type"][0], content_len)
	if err != nil {
		return err
	}
	// change to filename
	r.Image = filename
	return err
}

// GetKey gets
func GetKey(log *slog.Logger) error {
	const op = "parser.GetKey"

	log.Debug("Updating KEY...")
	defer log.Debug("KEY updated")
	str, err := client.WithHeader("Cookie", fmt.Sprintf("PHPSESSID=%s", PHPSESSID)).Post("/recipes").String()
	if err != nil {

		return fmt.Errorf("%s: %w", op, err)
	}
	i := strings.Index(str, "\"key\":")
	if i != 0 {
		parseKey = str[i+7 : i+47]
		log.Debug("New KEY", "key", parseKey)
		return nil
	}

	return fmt.Errorf("%s: %w", op, KeyNotFoundErr)
}

func GetPHPSESSID(log *slog.Logger) error {
	const op = "parser.GetPHPSESSID"

	log.Debug("Updating PHPSESSID...")
	defer log.Debug("PHPSESSID updated")
	form := make(url.Values)
	form.Add("page", "1")
	form.Add("action", "filter")
	form.Add("pageId", "7")
	form.Add("key", "-")
	resp, err := client.
		WithHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8").
		WithHeader("Cookie", "").
		Post("/assets/components/msearch2/action.php").WithForm(form).Do()
	if err != nil {
		return fmt.Errorf("%s: %w", op, err)
	}
	for _, c := range resp.Response().Cookies() {
		if c.Name == "PHPSESSID" {
			PHPSESSID = c.Value
			log.Debug("New PHPSESSID", "PHPSESSID", PHPSESSID)
			return nil
		}
	}

	return fmt.Errorf("%s: %w", op, CookieNotFoundErr)
}