package handlers

import (
	"encoding/json"
	"net/http"
	"strconv"

	"github.com/rede5/gohorsejobs/backend/internal/services"
)

type LocationHandlers struct {
	service *services.LocationService
}

func NewLocationHandlers(service *services.LocationService) *LocationHandlers {
	return &LocationHandlers{service: service}
}

// ListCountries returns all countries
func (h *LocationHandlers) ListCountries(w http.ResponseWriter, r *http.Request) {
	countries, err := h.service.ListCountries(r.Context())
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(countries)
}

// ListStatesByCountry returns states for a given country ID
// Expects path param {id}
func (h *LocationHandlers) ListStatesByCountry(w http.ResponseWriter, r *http.Request) {
	idStr := r.PathValue("id")
	if idStr == "" {
		http.Error(w, "Country ID is required", http.StatusBadRequest)
		return
	}

	countryID, err := strconv.ParseInt(idStr, 10, 64)
	if err != nil {
		http.Error(w, "Invalid Country ID", http.StatusBadRequest)
		return
	}

	states, err := h.service.ListStates(r.Context(), countryID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(states)
}

// ListCitiesByState returns cities for a given state ID
// Expects path param {id}
func (h *LocationHandlers) ListCitiesByState(w http.ResponseWriter, r *http.Request) {
	idStr := r.PathValue("id")
	if idStr == "" {
		http.Error(w, "State ID is required", http.StatusBadRequest)
		return
	}

	stateID, err := strconv.ParseInt(idStr, 10, 64)
	if err != nil {
		http.Error(w, "Invalid State ID", http.StatusBadRequest)
		return
	}

	cities, err := h.service.ListCities(r.Context(), stateID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(cities)
}

// SearchLocations searches for cities or states in a country
// Query params: q (query), country_id (required)
func (h *LocationHandlers) SearchLocations(w http.ResponseWriter, r *http.Request) {
	q := r.URL.Query().Get("q")
	countryIDStr := r.URL.Query().Get("country_id")

	if q == "" || len(q) < 2 {
		// Return empty list if query too short to avoid massive scan (though DB handles it, better UX)
		w.Header().Set("Content-Type", "application/json")
		w.Write([]byte("[]"))
		return
	}

	if countryIDStr == "" {
		http.Error(w, "country_id is required", http.StatusBadRequest)
		return
	}

	countryID, err := strconv.ParseInt(countryIDStr, 10, 64)
	if err != nil {
		http.Error(w, "Invalid country_id", http.StatusBadRequest)
		return
	}

	results, err := h.service.Search(r.Context(), q, countryID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(results)
}