package user

import (
	"context"
	"encoding/json"
	"fmt"
	"net/http"
	"time"

	"gitea.local/admin/hspguard/internal/auth"
	"gitea.local/admin/hspguard/internal/repository"
	"gitea.local/admin/hspguard/internal/web"
	"github.com/go-chi/chi/v5"
	"github.com/golang-jwt/jwt/v5"
)

type UserHandler struct {
	repo *repository.Queries
}

func NewUserHandler(repo *repository.Queries) *UserHandler {
	return &UserHandler{
		repo: repo,
	}
}

func (h *UserHandler) RegisterRoutes(router chi.Router, api chi.Router) {
	router.Get("/login", h.loginPage)
	router.Get("/register", h.registerPage)
	api.Post("/register", h.register)
	api.Post("/login", h.login)
}

func (h *UserHandler) loginPage(w http.ResponseWriter, r *http.Request) {
	data := map[string]any{
		"Title": "Login",
	}

	web.RenderTemplate(w, "login", data)
}

func (h *UserHandler) registerPage(w http.ResponseWriter, r *http.Request) {
	data := map[string]any{
		"Title": "Register",
	}

	web.RenderTemplate(w, "register", data)
}

type RegisterParams struct {
	FullName    string `json:"full_name"`
	Email       string `json:"email"`
	PhoneNumber string `json:"phone"`
	Password    string `json:"password"`
}

func (h *UserHandler) register(w http.ResponseWriter, r *http.Request) {
	var params RegisterParams

	decoder := json.NewDecoder(r.Body)
	if err := decoder.Decode(&params); err != nil {
		web.Error(w, "failed to parse request body", http.StatusBadRequest)
		return
	}

	if params.Email == "" || params.FullName == "" || params.Password == "" {
		web.Error(w, "missing required fields", http.StatusBadRequest)
		return
	}

	_, err := h.repo.FindUserEmail(context.Background(), params.Email)
	if err == nil {
		web.Error(w, "user with provided email already exists", http.StatusBadRequest)
		return
	}

	id, err := h.repo.InsertUser(context.Background(), repository.InsertUserParams{
		FullName:     params.FullName,
		Email:        params.Email,
		PasswordHash: params.Password,
		IsAdmin:      false,
	})
	if err != nil {
		web.Error(w, "failed to create new user", http.StatusInternalServerError)
		return
	}

	encoder := json.NewEncoder(w)

	type Response struct {
		Id string `json:"id"`
	}

	if err := encoder.Encode(Response{
		Id: id.String(),
	}); err != nil {
		web.Error(w, "failed to encode response", http.StatusInternalServerError)
	}
}

type LoginParams struct {
	Email       string `json:"email"`
	Password    string `json:"password"`
}

type UserClaims struct {
	UserID string `json:"user_id"`
	// Role
	jwt.RegisteredClaims
}

func (h *UserHandler) login(w http.ResponseWriter, r *http.Request) {
	var params LoginParams

	decoder := json.NewDecoder(r.Body)
	if err := decoder.Decode(&params); err != nil {
		web.Error(w, "failed to parse request body", http.StatusBadRequest)
		return
	}

	if params.Email == "" || params.Password == "" {
		web.Error(w, "missing required fields", http.StatusBadRequest)
		return
	}

	user, err := h.repo.FindUserEmail(context.Background(), params.Email)
	if err != nil {
		web.Error(w, "user with provided email does not exists", http.StatusBadRequest)
		return
	}

	claims := UserClaims{
		UserID: user.ID.String(),
		RegisteredClaims: jwt.RegisteredClaims{
			Issuer: "hspguard",
			Subject: user.Email,
			IssuedAt: jwt.NewNumericDate(time.Now()),
			ExpiresAt: jwt.NewNumericDate(time.Now().Add(time.Hour)),
		},
	}

	token, err := auth.SignJwtToken(claims)
	if err != nil {
		web.Error(w, fmt.Sprintf("failed to generate access token: %v", err), http.StatusBadRequest)
		return
	}

	encoder := json.NewEncoder(w)

	type Response struct {
		Token string `json:"token"`
	}

	if err := encoder.Encode(Response{
		Token: token,
	}); err != nil {
		web.Error(w, "failed to encode response", http.StatusInternalServerError)
	}
}