package main

import (
	"encoding/json"
	"fmt"
	"image-storage/auth"
	"image-storage/model"
	"io"
	"log"
	"net/http"
	"time"

	"github.com/jmoiron/sqlx"
	"golang.org/x/crypto/bcrypt"
	_ "modernc.org/sqlite"
)

func main() {
	db, err := sqlx.Connect("sqlite", "./db/sqlite.db")
	if err != nil {
		log.Fatalf("failed to connect to db: %v", err)
	}
	defer db.Close()

	srv := NewServer(":5000")

	srv.Handle("POST /api/auth/register", func(w http.ResponseWriter, r *http.Request) error {
		var body struct {
			Email    string `json:"email"`
			Password string `json:"password"`
		}
		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
			return srv.Error("empty body", err, 400)
		}

		if body.Email == "" || body.Password == "" {
			return srv.Error("email or password missing", nil, 400)
		}

		hash, err := bcrypt.GenerateFromPassword([]byte(body.Password), 10)
		if err != nil {
			return fmt.Errorf("failed to generate password hash: %v", err)
		}

		user := &model.User{
			Email:    body.Email,
			Password: string(hash),
		}

		if err := user.Create(db); err != nil {
			return srv.Error("failed to create user", err, 400)
		}

		if err := user.FindByID(db); err != nil {
			return fmt.Errorf("failed to populate user object after creating it: %v", err)
		}

		expiryTime := time.Now().Add(time.Hour * 24 * 30)
		token, err := auth.GenerateUserToken(user.ID, expiryTime)
		if err != nil {
			return fmt.Errorf("failed to generate access token: %v", err)
		}
		auth.SetUserCookie(w, token, expiryTime)

		return srv.JSON(w, user, 201)
	})

	srv.Handle("POST /api/auth/login", func(w http.ResponseWriter, r *http.Request) error {
		var body struct {
			Email    string `json:"email"`
			Password string `json:"password"`
		}
		if err := json.NewDecoder(r.Body).Decode(&body); err != nil {
			return srv.Error("empty body", err, 400)
		}

		if body.Email == "" || body.Password == "" {
			return srv.Error("email or password missing", nil, 400)
		}

		user := &model.User{Email: body.Email}
		if err := user.FindByEmail(db); err != nil {
			return srv.Error("user not found", err, 404)
		}

		if err := bcrypt.CompareHashAndPassword([]byte(user.Password), []byte(body.Password)); err != nil {
			return srv.Error("invalid password", nil, 400)
		}

		expiryTime := time.Now().Add(time.Hour * 24 * 30)
		token, err := auth.GenerateUserToken(user.ID, expiryTime)
		if err != nil {
			return fmt.Errorf("failed to generate access token: %v", err)
		}
		auth.SetUserCookie(w, token, expiryTime)

		return srv.JSON(w, user, 200)
	})

	srv.Handle("POST /api/images", func(w http.ResponseWriter, r *http.Request) error {
		userId, err := auth.GetUserIdFromRequest(r)
		if err != nil {
			return srv.Error("unauthorized", err, 401)
		}

		user := &model.User{Model: model.Model{ID: userId}}
		if err := user.FindByID(db); err != nil {
			return srv.Error("user not found", nil, 401)
		}

		data, err := io.ReadAll(r.Body)
		if err != nil {
			return fmt.Errorf("failed to read request body: %v", err)
		}

		if len(data) == 0 {
			return srv.Error("empty body", nil, 400)
		}

		img := &model.Image{
			UserID:      user.ID,
			Data:        data,
			ContentType: r.Header.Get("Content-Type"),
		}
		if err := img.Create(db); err != nil {
			return srv.Error("failed to save image to database: %v", err, 400)
		}

		return srv.JSON(w, img, 201)
	})

	srv.Handle("GET /api/images", func(w http.ResponseWriter, r *http.Request) error {
		userId, err := auth.GetUserIdFromRequest(r)
		if err != nil {
			return srv.Error("unauthorized", err, 401)
		}

		rows, err := db.Queryx("SELECT * FROM images WHERE user_id = ?", userId)
		if err != nil {
			return srv.Error("images not found", err, 400)
		}

		images := []model.Image{}
		for rows.Next() {
			img := model.Image{}
			if err := rows.StructScan(&img); err != nil {
				log.Printf("failed to save image to struct: %v", err)
				continue
			}
			images = append(images, img)
		}

		return srv.JSON(w, images, 200)
	})

	srv.Handle("GET /images/{id}", func(w http.ResponseWriter, r *http.Request) error {
		img := &model.Image{ID: r.PathValue("id")}
		if err := img.FindByID(db); err != nil {
			return srv.Error("image not found", nil, 404)
		}

		w.Header().Set("Content-Type", img.ContentType)
		w.Write(img.Data)

		return nil
	})

	srv.Handle("DELETE /api/images/{id}", func(w http.ResponseWriter, r *http.Request) error {
		img := &model.Image{ID: r.PathValue("id")}
		if err := img.FindByID(db); err != nil {
			return srv.Error("image not found", nil, 404)
		}

		if err := img.DeleteByID(db); err != nil {
			return srv.Error("failed to delete image: %v", err, 500)
		}

		return srv.JSON(w, struct {
			Ok bool `json:"ok"`
		}{true}, 200)
	})

	if err := srv.ListenAndServe(); err != nil {
		log.Fatalf("failed to start http server: %v", err)
	}
}