package http

import (
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"

	"primaya-api/cpone-middleware/internal/repository"
)

type PaketValidationResponse struct {
	Success bool   `json:"success"`
	Status  string `json:"status"`
	Message string `json:"message"`
	Data    any    `json:"data"`
}

type PaketPaginationResponse struct {
	CurrentPage  int                       `json:"current_page"`
	Data         []repository.PaketSummary `json:"data"`
	FirstPageURL string                    `json:"first_page_url"`
	From         *int                      `json:"from"`
	LastPage     int                       `json:"last_page"`
	LastPageURL  string                    `json:"last_page_url"`
	Links        map[string]any            `json:"links"`
	NextPageURL  *string                   `json:"next_page_url"`
	Total        int                       `json:"total"`
	PerPage      int                       `json:"per_page"`
}

func (h Handler) ListPaket(w http.ResponseWriter, r *http.Request) {
	params, message := parsePaketListParams(r)
	if message != "" {
		writePaketValidationError(w, message)
		return
	}

	page, err := h.paketRepository(r.Context()).ListPaket(r.Context(), params)
	if err != nil {
		WriteJSON(w, http.StatusInternalServerError, Response{
			Success: false, Message: "internal server error", Data: nil,
		})
		return
	}

	lastPage := (page.Total + params.PerPage - 1) / params.PerPage
	if lastPage < 1 {
		lastPage = 1
	}
	var from *int
	if len(page.Items) > 0 {
		value := (params.Page-1)*params.PerPage + 1
		from = &value
	}
	var nextPageURL *string
	if params.Page < lastPage {
		value := currentRequestURL(r, params.Page+1)
		nextPageURL = &value
	}

	WriteJSON(w, http.StatusOK, PaketPaginationResponse{
		CurrentPage:  params.Page,
		Data:         page.Items,
		FirstPageURL: "",
		From:         from,
		LastPage:     lastPage,
		LastPageURL:  "",
		Links:        map[string]any{},
		NextPageURL:  nextPageURL,
		Total:        page.Total,
		PerPage:      params.PerPage,
	})
}

func (h Handler) GetPaket(w http.ResponseWriter, r *http.Request) {
	id := strings.TrimSpace(r.PathValue("id"))
	paket, err := h.paketRepository(r.Context()).GetPaket(r.Context(), id)
	if err != nil {
		WriteJSON(w, http.StatusInternalServerError, Response{
			Success: false, Message: "internal server error", Data: nil,
		})
		return
	}
	if paket == nil {
		WriteJSON(w, http.StatusNotFound, Response{
			Success: false, Message: "Data tidak ditemukan", Data: nil,
		})
		return
	}

	WriteJSON(w, http.StatusOK, Response{Success: true, Message: "ok", Data: paket})
}

func parsePaketListParams(r *http.Request) (repository.PaketListParams, string) {
	query := r.URL.Query()
	params := repository.PaketListParams{
		Search: query.Get("search"), Code: query.Get("code"),
		CareType: query.Get("care_type"), Active: query.Get("active"),
		StartDate: query.Get("start_date"), EndDate: query.Get("end_date"),
		Status: 2, Page: 1, PerPage: 15,
	}

	if params.CareType != "" && params.CareType != "RI" && params.CareType != "RJ" {
		return params, "The selected care type is invalid."
	}
	if raw, exists := firstQueryValue(r, "status"); exists && raw != "" {
		value, err := strconv.Atoi(raw)
		if err != nil {
			return params, "The status must be an integer."
		}
		if value < -1 || value > 2 {
			return params, "The selected status is invalid."
		}
		params.Status = value
	}
	if params.Active != "" && params.Active != "N" && params.Active != "Y" {
		return params, "The selected active is invalid."
	}
	if params.StartDate != "" {
		if _, err := time.Parse("2006-01-02", params.StartDate); err != nil {
			return params, "The start date does not match the format Y-m-d."
		}
	}
	if params.EndDate != "" {
		end, err := time.Parse("2006-01-02", params.EndDate)
		if err != nil {
			return params, "The end date does not match the format Y-m-d."
		}
		if params.StartDate != "" {
			start, _ := time.Parse("2006-01-02", params.StartDate)
			if end.Before(start) {
				return params, "The end date must be a date after or equal to start date."
			}
		}
	}
	if raw, exists := firstQueryValue(r, "page"); exists && raw != "" {
		value, err := strconv.Atoi(raw)
		if err != nil {
			return params, "The page must be an integer."
		}
		if value < 1 {
			return params, "The page must be at least 1."
		}
		params.Page = value
	}
	if raw, exists := firstQueryValue(r, "per_page"); exists && raw != "" {
		value, err := strconv.Atoi(raw)
		if err != nil {
			return params, "The per page must be an integer."
		}
		if value < 1 || value > 100 {
			return params, "The per page must be between 1 and 100."
		}
		params.PerPage = value
	}

	return params, ""
}

func currentRequestURL(r *http.Request, page int) string {
	scheme := "http"
	if r.TLS != nil {
		scheme = "https"
	}
	if forwarded := r.Header.Get("X-Forwarded-Proto"); forwarded != "" {
		scheme = strings.TrimSpace(strings.Split(forwarded, ",")[0])
	}
	host := r.Host
	if host == "" {
		host = "localhost"
	}
	query := url.Values{}
	if code := r.URL.Query().Get("kode_rs"); code != "" {
		query.Set("kode_rs", code)
	}
	query.Set("page", strconv.Itoa(page))
	return (&url.URL{Scheme: scheme, Host: host, Path: r.URL.Path, RawQuery: query.Encode()}).String()
}

func writePaketValidationError(w http.ResponseWriter, message string) {
	WriteJSON(w, http.StatusUnprocessableEntity, PaketValidationResponse{
		Success: false, Status: "validation_error", Message: message, Data: nil,
	})
}