package handlers

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

	"github.com/rede5/gohorsejobs/backend/internal/api/middleware"
	"github.com/rede5/gohorsejobs/backend/internal/models"
)

type CompanyFollowerServiceInterface interface {
	Follow(userID, companyID string) (*models.CompanyFollower, error)
	Unfollow(userID, companyID string) error
	GetFollowing(userID string) ([]models.CompanyFollowerWithCompany, error)
	IsFollowing(userID, companyID string) (bool, error)
	GetCompaniesWithJobs(limit, offset int) ([]models.CompanyFollowerWithCompany, error)
}

type CompanyFollowerHandler struct {
	Service CompanyFollowerServiceInterface
}

func NewCompanyFollowerHandler(service CompanyFollowerServiceInterface) *CompanyFollowerHandler {
	return &CompanyFollowerHandler{Service: service}
}

func (h *CompanyFollowerHandler) Follow(w http.ResponseWriter, r *http.Request) {
	userID, ok := r.Context().Value(middleware.ContextUserID).(string)
	if !ok || userID == "" {
		http.Error(w, "Unauthorized", http.StatusUnauthorized)
		return
	}

	companyID := strings.TrimPrefix(r.URL.Path, "/api/v1/companies/follow/")

	follower, err := h.Service.Follow(userID, companyID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusCreated)
	json.NewEncoder(w).Encode(follower)
}

func (h *CompanyFollowerHandler) Unfollow(w http.ResponseWriter, r *http.Request) {
	userID, ok := r.Context().Value(middleware.ContextUserID).(string)
	if !ok || userID == "" {
		http.Error(w, "Unauthorized", http.StatusUnauthorized)
		return
	}

	companyID := strings.TrimPrefix(r.URL.Path, "/api/v1/companies/follow/")

	err := h.Service.Unfollow(userID, companyID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.WriteHeader(http.StatusNoContent)
}

func (h *CompanyFollowerHandler) GetMyFollowing(w http.ResponseWriter, r *http.Request) {
	userID, ok := r.Context().Value(middleware.ContextUserID).(string)
	if !ok || userID == "" {
		http.Error(w, "Unauthorized", http.StatusUnauthorized)
		return
	}

	following, err := h.Service.GetFollowing(userID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

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

func (h *CompanyFollowerHandler) CheckFollowing(w http.ResponseWriter, r *http.Request) {
	userID, ok := r.Context().Value(middleware.ContextUserID).(string)
	if !ok || userID == "" {
		http.Error(w, "Unauthorized", http.StatusUnauthorized)
		return
	}

	companyID := strings.TrimPrefix(r.URL.Path, "/api/v1/companies/")

	isFollowing, err := h.Service.IsFollowing(userID, companyID)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(map[string]bool{"isFollowing": isFollowing})
}

func (h *CompanyFollowerHandler) GetCompanies(w http.ResponseWriter, r *http.Request) {
	companies, err := h.Service.GetCompaniesWithJobs(20, 0)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

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