package handlers

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

	"github.com/julienschmidt/httprouter"

	"otpm/api"
	"otpm/middleware"
	"otpm/models"
	"otpm/services"
)

// OTPHandler handles OTP-related HTTP requests
type OTPHandler struct {
	otpService *services.OTPService
}

// NewOTPHandler creates a new OTPHandler
func NewOTPHandler(otpService *services.OTPService) *OTPHandler {
	return &OTPHandler{
		otpService: otpService,
	}
}

// Routes returns the routes for OTP operations
func (h *OTPHandler) Routes() map[string]httprouter.Handle {
	return map[string]httprouter.Handle{
		"POST /api/otp":    h.CreateOTP,
		"GET /api/otps":    h.ListOTPs,
		"GET /api/otp/:id": h.GetOTP,
	}
}

// CreateOTP handles the creation of a new OTP
func (h *OTPHandler) CreateOTP(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
	// Get user ID from context
	userID, ok := r.Context().Value(middleware.UserIDKey).(string)
	if !ok {
		api.NewResponseWriter(w).WriteError(api.ErrUnauthorized)
		return
	}

	// Parse request body
	var params models.OTPParams
	if err := json.NewDecoder(r.Body).Decode(&params); err != nil {
		api.NewResponseWriter(w).WriteError(api.ValidationError("Invalid request body"))
		return
	}

	// Validate request
	if err := api.Validate.Struct(params); err != nil {
		api.NewResponseWriter(w).WriteError(api.ValidationError(err.Error()))
		return
	}

	// Create OTP
	otp, err := h.otpService.CreateOTP(r.Context(), userID, params)
	if err != nil {
		api.NewResponseWriter(w).WriteError(api.InternalError(err))
		return
	}

	// Return response
	api.NewResponseWriter(w).WriteSuccess(otp)
}

// ListOTPs handles listing all OTPs for a user
func (h *OTPHandler) ListOTPs(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
	// Get user ID from context
	userID, ok := r.Context().Value(middleware.UserIDKey).(string)
	if !ok {
		api.NewResponseWriter(w).WriteError(api.ErrUnauthorized)
		return
	}

	// Get OTPs
	otps, err := h.otpService.ListOTPs(r.Context(), userID)
	if err != nil {
		api.NewResponseWriter(w).WriteError(api.InternalError(err))
		return
	}

	// Return response
	api.NewResponseWriter(w).WriteSuccess(otps)
}

// GetOTP handles getting a specific OTP
func (h *OTPHandler) GetOTP(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
	// Get user ID from context
	userID, ok := r.Context().Value(middleware.UserIDKey).(string)
	if !ok {
		api.NewResponseWriter(w).WriteError(api.ErrUnauthorized)
		return
	}

	// Get OTP ID from URL
	otpID := ps.ByName("id")
	if otpID == "" {
		api.NewResponseWriter(w).WriteError(api.ValidationError("Missing OTP ID"))
		return
	}

	// Get OTP
	otp, err := h.otpService.GetOTP(r.Context(), otpID, userID)
	if err != nil {
		api.NewResponseWriter(w).WriteError(api.InternalError(err))
		return
	}

	// Return response
	api.NewResponseWriter(w).WriteSuccess(otp)
}