// JavaScript that handles the dynamic ordering quantities on the ordering page.
//
// In a JavaScript block on the actual view, define the article data by calls to setData().
// You should also set the available group balance through setGroupBalance(amount).
//
// Call setDecimalSeparator(char) to overwrite the default character "." with a localized value.

var modified = false    		// indicates if anything has been clicked on this page
var groupBalance = 0;			// available group money 
var decimalSeparator = ".";		// default decimal separator
var toleranceIsCostly = true; // default tolerance behaviour

// Article data arrays:
var price = new Array();
var unit = new Array();  		// items per order unit
var itemTotal = new Array();    // total item price
var quantityOthers = new Array();
var toleranceOthers = new Array();
var itemsAllocated = new Array();  // how many items the group has been allocated and should definitely get
var quantityAvailable = new Array();  // stock_order. how many items are currently in stock

function setDecimalSeparator(character) {
    decimalSeparator = character;
}

function setToleranceBehaviour(value) {
    toleranceIsCostly = value;
}

function setGroupBalance(amount) {
    groupBalance = amount;
}

function addData(itemPrice, itemUnit, itemSubtotal, itemQuantityOthers, itemToleranceOthers, allocated, available) {
    i = price.length;
    price[i] = itemPrice;
    unit[i] = itemUnit;
    itemTotal[i] = itemSubtotal;
    quantityOthers[i] = itemQuantityOthers;
    toleranceOthers[i] = itemToleranceOthers;
    itemsAllocated[i] = allocated;
    quantityAvailable[i] = available;
}

function increaseQuantity(item) {
    value = Number($('#q_' + item).val()) + 1;
    update(item, value, $('#t_' + item).val());
}

function decreaseQuantity(item) {
    value = Number($('#q_' + item).val()) - 1;
    if (value >= 0) {
        update(item, value, $('#t_' + item).val());
    }
}

function increaseTolerance(item) {
    value = Number($('#t_' + item).val()) + 1;
    update(item, $('#q_' + item).val(), value);
}

function decreaseTolerance(item) {
    value = Number($('#t_' + item).val()) - 1;
    if (value >= 0) {
        update(item, $('#q_' + item).val(), value);
    }
}

function update(item, quantity, tolerance) {
    // set modification flag
    modified = true

    // update hidden input fields
    $('#q_' + item).val(quantity);
    $('#t_' + item).val(tolerance);

    // calculate how many units would be ordered in total
    units = calcUnits(unit[item], quantityOthers[item] + Number(quantity), toleranceOthers[item] + Number(tolerance));
    if (unitCompletedFromTolerance(unit[item], quantityOthers[item] + Number(quantity), toleranceOthers[item] + Number(tolerance))) {
        $('#units_' + item).html('<span style="color:grey">' + String(units) + "</span>");
    } else {
        $('#units_' + item).html(String(units));
    }

    // update used/unused quantity
    available = Math.max(0, units * unit[item] - quantityOthers[item]);
    q_used = Math.min(available, quantity);
    // ensure that at least the amout of items this group has already been allocated is used
    if (quantity >= itemsAllocated[item] && q_used < itemsAllocated[item]) {
        q_used = itemsAllocated[item];
    }
    $('#q_used_' + item).html(String(q_used));
    $('#q_unused_' + item).html(String(quantity - q_used));
    $('#q_total_' + item).html(String(Number(quantity) + quantityOthers[item]));

    // update used/unused tolerance
    if (unit[item] > 1) {
        available = Math.max(0, available - q_used - toleranceOthers[item]);
        t_used = Math.min(available, tolerance);
        $('#t_used_' + item).html(String(t_used));
        $('#t_unused_' + item).html(String(tolerance - t_used));
        $('#t_total_' + item).html(String(Number(tolerance) + toleranceOthers[item]));
    }

    // update total price
    if(toleranceIsCostly == true) {
        itemTotal[item] = price[item] * (Number(quantity) + Number(tolerance));
    } else {
        itemTotal[item] = price[item] * (Number(quantity));
    }
    $('#price_' + item + '_display').html(asMoney(itemTotal[item]));

    // update missing units
    missing_units = unit[item] - (((quantityOthers[item] + Number(quantity)) % unit[item]) + Number(tolerance) + toleranceOthers[item])
    if (missing_units < 0) {
        missing_units = 0;
    }
    $('#missing_units_' + item).html(String(missing_units));

    // update balance
    updateBalance();
}

function increaseStockQuantity(item) {
    value = Number($('#q_' + item).val()) + 1;
    if (value <= quantityAvailable[item] - quantityOthers[item]) {
        updateStockQuantity(item, value);
    }
}

function decreaseStockQuantity(item) {
    value = Number($('#q_' + item).val()) - 1;
    if (value >= 0) {
        updateStockQuantity(item, value);
    }
}

function updateStockQuantity(item, quantity) {
    // set modification flag
    modified = true

    // update hidden input fields
    $('#q_' + item).val() = quantity;

    // update used/unused quantity
    available = Math.max(0, quantityAvailable[item] - quantityOthers[item]);
    q_used = Math.min(available, quantity);

    // ensure that at least the amout of items this group has already been allocated is used
    if (quantity >= itemsAllocated[item] && q_used < itemsAllocated[item]) {
        q_used = itemsAllocated[item];
    }
    $('#q_used_' + item).html(String(q_used));
    $('#q_total_' + item).html(String(Number(quantity) + quantityOthers[item]));

    // update total price
    itemTotal[item] = price[item] * (Number(quantity));
    $('#price_' + item + '_display').html(asMoney(itemTotal[item]));

    // update balance
    updateBalance();
}

function asMoney(amount) {
    return String(amount.toFixed(2)).replace(/\./, ",");
}

function calcUnits(unitSize, quantity, tolerance) {
    units = Math.floor(quantity / unitSize)
    remainder = quantity % unitSize
    return units + ((remainder > 0) && (remainder + tolerance >= unitSize) ? 1 : 0)
}

function unitCompletedFromTolerance(unitSize, quantity, tolerance) {
    remainder = quantity % unitSize
    return (remainder > 0 && (remainder + tolerance >= unitSize));
}

function updateBalance() {
    // update total price and order balance
    total = 0;
    for (i = 0; i < itemTotal.length; i++) {
        total += itemTotal[i];
    }
    $('#total_price').html(asMoney(total));
    balance = groupBalance - total;
    $('#new_balance').html(asMoney(balance));
    $('#total_balance').val(asMoney(balance));
    // determine bgcolor and submit button state according to balance 
    if (balance < 0) {
        bgcolor = '#FF0000';
        $('#submit_button').disabled = true;
    } else {
        bgcolor = '';
        $('#submit_button').disabled = false;
    }
    // update bgcolor
    for (i = 0; i < itemTotal.length; i++) {
        $('#ltd_price_' + i).css('background-color', bgcolor);
    }
}

function confirmSwitchOrder() {
    return (!modified || confirm('Änderungen an dieser Bestellung gehen verloren, wenn zu einer anderen Bestellung gewechselt wird.'))
}