const Category = require('./categoryModel')
const AppError = require('../../globalErrorHandler/AppError')

module.exports.getCategoryTree = async () => {
    const nodes = await Category.find({})
    let tree = []
    for (let i = 0; i < nodes.length; i++) {
        if (!nodes[i].parentId) {
            const label = nodes[i].nativeName
            const children = []
            const key = nodes[i]._id.toString()
            const href = '/categories/admin/update/' + nodes[i]._id
            const a_attr = { href }
            const root = { label, children, key, a_attr }
            tree.push(root)
        }
    }

    tree = recursiveFunction(tree, nodes)
    return tree
}

const recursiveFunction = (tree, categories) => {
    if (tree.length > 0) {
        for (let i = 0; i < tree.length; i++) {
            let subTree = []
            for (let j = 0; j < categories.length; j++) {
                if (tree[i].key === categories[j].parentId?.toString()) {
                    const label = categories[j].nativeName.toString()
                    const children = []
                    const key = categories[j]._id.toString()
                    const href = '/categories/admin/update/' + categories[j]._id
                    const a_attr = { href }
                    subTree.push({ label, children, key, a_attr })
                }
                let index = findCategoryIndex(tree, tree[i].label)
                tree[index].children = subTree
            }
        }
        for (let i = 0; i < tree.length; i++) {
            let index = findCategoryIndex(tree, tree[i].label)
            recursiveFunction(tree[index].children, categories)
        }
    }
    return tree
}

function findCategoryIndex(array, label) {
    let index
    for (let i = 0; i < array.length; i++) {
        if (array[i].label === label) {
            index = i
            return index
        }
    }
}

module.exports.getAllCategories = async () => {
    return Category.find().populate('parentId')
}

module.exports.createCategory = async (data) => {
    const category = Category.create(data, null)
    return category
}

module.exports.getCategory = async (categoryId) => {
    const category = await Category.findById(categoryId)

    if (!category) {
        throw new AppError('NoCategoryFound', 404, {})
    }

    return category
}

module.exports.updateCategory = async (categoryId, data) => {
    const category = await Category.findOneAndUpdate({ _id: categoryId }, data, { new: true })

    if (!category) {
        throw new AppError('NoCategoryFound', 404, {})
    }

    return category
}

module.exports.deleteCategory = async (categoryId) => {
    const category = await Category.findByIdAndDelete(categoryId)

    if (!category) {
        throw new AppError('NoCategoryFound', 404, {})
    }

    return null
}