package handlers

import (
	"log"
	"slices"

	"git.odit.services/lfk/document-server/models"
	"git.odit.services/lfk/document-server/services"
	"github.com/gofiber/fiber/v2"
)

// GenerateCard godoc
// @Summary Generate runner cards
// @Description Generate cards based on the provided data
// @Tags cards
// @Accept json
// @Param data body models.CardRequest true "Card data"
// @Produce application/pdf
// @Router /cards [post]
func (h *DefaultHandler) GenerateCard(c *fiber.Ctx) error {
	cardRequest := new(models.CardRequest)
	if err := c.BodyParser(cardRequest); err != nil {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"error": err.Error(),
		})
	}
	if !slices.Contains([]string{"en", "de"}, cardRequest.Locale) {
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"error": "Invalid locale",
		})
	}

	generator := services.DefaultTemplater{}
	templateString, err := services.GetTemplate(cardRequest.Locale, "card")
	if err != nil {
		log.Println(err)
		return c.Status(fiber.StatusBadRequest).JSON(fiber.Map{
			"error": "Template not found",
		})
	}
	template, err := generator.StringToTemplate(templateString)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": err.Error(),
		})
	}

	genConfig := &models.CardTemplateOptions{
		CardSegments:  splitCardSegments(cardRequest.Cards),
		EventName:     h.Config.EventName,
		CardSubtitle:  h.Config.CardSubtitle,
		BarcodeFormat: h.Config.CardBarcodeFormat,
		BarcodePrefix: h.Config.CardBarcodePrefix,
	}

	result, err := generator.Execute(template, genConfig)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": err.Error(),
		})
	}
	c.Set(fiber.HeaderContentType, "text/html")
	converter := services.GotenbergConverter{BaseUrl: "http://localhost:3001"}
	pdf, err := converter.ToPdf(result, "a4", false)
	if err != nil {
		return c.Status(fiber.StatusInternalServerError).JSON(fiber.Map{
			"error": err.Error(),
		})
	}

	c.Set(fiber.HeaderContentType, "application/pdf")
	return c.Send(pdf)
}

func invertCardArrayItemPairs(cards []models.Card) []models.Card {
	inverted := make([]models.Card, 0)
	for i := 0; i < len(cards); i += 2 {
		if i+1 < len(cards) {
			inverted = append(inverted, cards[i+1])
		}
		inverted = append(inverted, cards[i])
	}
	return inverted
}

func splitCardSegments(cards []models.Card) []models.CardTemplateSegment {
	cardSegments := make([]models.CardTemplateSegment, 0)
	const currentCards = 0
	for i := 0; i < len(cards); i += 10 {
		segmentLength := 10
		if len(cards)-i < 10 {
			segmentLength = len(cards) - i
		}
		segment := cards[i : i+segmentLength]
		if segmentLength%2 != 0 {
			segment = append(segment, models.Card{
				ID:      0,
				Enabled: false,
				Runner:  models.Runner{},
				Code:    "",
			})
		}
		cardSegments = append(cardSegments, models.CardTemplateSegment{
			Cards:        segment,
			CardsSwapped: invertCardArrayItemPairs(segment),
		})
	}
	return cardSegments
}