module.exports = {
    isPopulated: false,
    ingredients: [],

    display: function(){
        if(!this.isPopulated){
            this.populateByProperty("category");

            document.getElementById("ingredientSearch").oninput = ()=>{this.search()};
            document.getElementById("ingredientClearButton").onclick = ()=>{this.clearSorting()};
            document.getElementById("ingredientSelect").onchange = ()=>{this.sort()};

            this.isPopulated = true;
        }
    },

    populateByProperty: function(property){
        let categories;
        if(property === "category"){
            categories = merchant.categorizeIngredients();
        }else if(property === "unit"){
            categories = merchant.unitizeIngredients();
        }
        
        let ingredientStrand = document.getElementById("categoryList");
        let categoryTemplate = document.getElementById("categoryDiv").content.children[0];
        let ingredientTemplate = document.getElementById("ingredient").content.children[0];
        this.ingredients = [];

        while(ingredientStrand.children.length > 0){
            ingredientStrand.removeChild(ingredientStrand.firstChild);
        }

        for(let i = 0; i < categories.length; i++){
            let categoryDiv = categoryTemplate.cloneNode(true);
            categoryDiv.children[0].children[0].innerText = categories[i].name;
            
            categoryDiv.children[0].children[1].onclick = ()=>{
                this.toggleCategory(categoryDiv.children[1], categoryDiv.children[0].children[1]);
            };
            categoryDiv.children[1].style.display = "none";
            ingredientStrand.appendChild(categoryDiv);

            for(let j = 0; j < categories[i].ingredients.length; j++){
                let ingredient = categories[i].ingredients[j];
                let ingredientDiv = ingredientTemplate.cloneNode(true);

                ingredientDiv.children[0].innerText = ingredient.ingredient.name;
                ingredientDiv.children[2].innerText = `${ingredient.ingredient.convert(ingredient.quantity).toFixed(2)} ${ingredient.ingredient.unit.toUpperCase()}`;
                ingredientDiv.onclick = ()=>{controller.openSidebar("ingredientDetails", ingredient)};
                ingredientDiv._name = ingredient.ingredient.name.toLowerCase();
                ingredientDiv._unit = ingredient.ingredient.unit.toLowerCase();

                categoryDiv.children[1].appendChild(ingredientDiv);
                this.ingredients.push(ingredientDiv);
            }
        }

    },

    displayIngredientsOnly: function(ingredients){
        let ingredientDiv = document.getElementById("categoryList");

        while(ingredientDiv.children.length > 0){
            ingredientDiv.removeChild(ingredientDiv.firstChild);
        }
        for(let i = 0; i < ingredients.length; i++){
            ingredientDiv.appendChild(ingredients[i]);
        }
    },

    toggleCategory: function(div, button){
        if(div.style.display === "none"){
            button.innerHTML = '<svg width="32" height="32" viewBox="0 0 24 24" fill="none" stroke="black" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="18 15 12 9 6 15"></polyline></svg>';
            div.style.display = "flex";
        }else if(div.style.display === "flex"){
            button.innerHTML = '<svg width="32" height="32" viewBox="0 0 24 24" fill="none" stroke="black" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="6 9 12 15 18 9"></polyline></svg>';
            div.style.display = "none";
        }
    },

    search: function(){
        let input = document.getElementById("ingredientSearch").value.toLowerCase();
        document.getElementById("ingredientSelect").selectedIndex = 0;

        if(input === ""){
            this.populateByProperty("category");
            document.getElementById("ingredientClearButton").style.display = "none";
            return;
        }

        let matchingIngredients = [];
        for(let i = 0; i < this.ingredients.length; i++){
            if(this.ingredients[i]._name.includes(input)){
                matchingIngredients.push(this.ingredients[i]);
            }
        }

        document.getElementById("ingredientClearButton").style.display = "inline";
        this.displayIngredientsOnly(matchingIngredients);
    },

    sort: function(){
        let sortType = document.getElementById("ingredientSelect").value;
        
        if(sortType === ""){
            return;
        }

        document.getElementById("ingredientSearch").value = "";

        if(sortType === "category"){
            this.populateByProperty("category");
            return;
        }

        if(sortType === "unit"){
            this.populateByProperty("unit");
            return;
        }

        document.getElementById("ingredientClearButton").style.display = "inline";
        let sortedIngredients = this.ingredients.slice().sort((a, b)=> (a[sortType] > b[sortType]) ? 1 : -1);
        this.displayIngredientsOnly(sortedIngredients);
    },

    clearSorting: function(button){
        document.getElementById("ingredientSearch").value = "";
        document.getElementById("ingredientSelect").selectedIndex = 0;
        document.getElementById("ingredientClearButton").style.display = "none";

        this.populateByProperty("category");
    }
}