package database

import (
	"backend/model"
	"encoding/json"
	"errors"
	"fmt"
	"os"
	"strings"

	"gorm.io/gorm"
)

func CreateCategory(category *model.Category) error {
	e := Db.Where(model.Category{
		Title: category.Title,
	}).FirstOrCreate(&category).Error
	if e != nil {
		return e
	}
	return nil
}

func GetCategoryById(id string) (*model.Category, error) {
	var category model.Category
	e := Db.First(&category, "id = ?", id).Error
	if e != nil {
		if errors.Is(e, gorm.ErrRecordNotFound) {
			return nil, fmt.Errorf("user not found")
		}
		return nil, e
	}
	return &category, nil
}

func GetCategoryByTitle(title string) (*model.Category, error) {
	var category model.Category
	e := Db.First(&category, "username = ?", title).Error
	if e != nil {
		if errors.Is(e, gorm.ErrRecordNotFound) {
			return nil, fmt.Errorf("user not found")
		}
		return nil, e
	}
	return &category, nil
}

func DeleteCategory(id string) error {
	var category model.Category
	e := Db.First(&category, "id = ?", id).Error
	if e != nil {
		if errors.Is(e, gorm.ErrRecordNotFound) {
			return fmt.Errorf("user not found")
		}
		return e
	}
	e = Db.Unscoped().Delete(&category).Error
	if e != nil {
		if errors.Is(e, gorm.ErrRecordNotFound) {
			return fmt.Errorf("user not found")
		}
		return e
	}
	return nil
}

func GetCategoriesFromFile(filename string) []model.Category {
	data, e := os.ReadFile(filename)
	if e != nil {
		panic(e)
	}
	decoder := json.NewDecoder(strings.NewReader(string(data)))
	var res []model.Category
	decoder.Decode(&res)
	return res
}

func GetAllCategories() ([]model.Category, error) {
	var categories []model.Category
	e := Db.Find(&categories).Error
	if e != nil {
		return nil, e
	}
	for i := range categories {
		var subcategories []model.Subcategory
		e := Db.Where(model.Subcategory{CategoryID: categories[i].ID}).Find(&subcategories).Error
		if e != nil {
			return nil, e
		}
		categories[i].Subcategories = subcategories
	}
	return categories, nil
}