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#include "astpropertiesitemhandler.h"

#include <language/item.h>
#include <language/value.h>

#include <logging/translator.h>
#include <tools/error.h>
#include <tools/qbsassert.h>
#include <tools/stringconstants.h>

namespace qbs {
namespace Internal {

ASTPropertiesItemHandler::ASTPropertiesItemHandler(Item *parentItem, ItemPool &itemPool)
    : m_parentItem(parentItem), m_itemPool(itemPool)
{
}

void ASTPropertiesItemHandler::handlePropertiesItems()
{
    // TODO: Simply forbid Properties items to have child items and get rid of this check.
    if (m_parentItem->type() != ItemType::Properties)
        setupAlternatives();
}

void ASTPropertiesItemHandler::setupAlternatives()
{
    auto it = m_parentItem->m_children.begin();
    while (it != m_parentItem->m_children.end()) {
        Item * const child = *it;
        bool remove = false;
        if (child->type() == ItemType::Properties) {
            handlePropertiesBlock(child);
            remove = m_parentItem->type() != ItemType::Export;
        }
        if (remove)
            it = m_parentItem->m_children.erase(it);
        else
            ++it;
    }
}

class PropertiesBlockConverter
{
public:
    PropertiesBlockConverter(const JSSourceValue::AltProperty &condition,
                             const JSSourceValue::AltProperty &overrideListProperties,
                             Item *propertiesBlockContainer, const Item *propertiesBlock,
                             ItemPool &pool)
        : m_propertiesBlockContainer(propertiesBlockContainer)
        , m_propertiesBlock(propertiesBlock)
        , m_itemPool(pool)
    {
        m_alternative.condition = condition;
        m_alternative.overrideListProperties = overrideListProperties;
    }

    void apply()
    {
        doApply(m_propertiesBlockContainer, m_propertiesBlock);
    }

private:
    JSSourceValue::Alternative m_alternative;
    Item * const m_propertiesBlockContainer;
    const Item * const m_propertiesBlock;
    ItemPool &m_itemPool;

    void doApply(Item *outer, const Item *inner)
    {
        for (auto it = inner->properties().constBegin();
                it != inner->properties().constEnd(); ++it) {
            if (inner == m_propertiesBlock
                    && (it.key() == StringConstants::conditionProperty()
                        || it.key() == StringConstants::overrideListPropertiesProperty())) {
                continue;
            }
            if (it.value()->type() == Value::ItemValueType) {
                Item * const innerVal = std::static_pointer_cast<ItemValue>(it.value())->item();
                ItemValuePtr outerVal = outer->itemProperty(it.key(), m_itemPool);
                if (!outerVal) {
                    outerVal = ItemValue::create(Item::create(&m_itemPool, innerVal->type()),
                                                 true);
                    outer->setProperty(it.key(), outerVal);
                }
                doApply(outerVal->item(), innerVal);
            } else if (it.value()->type() == Value::JSSourceValueType) {
                const ValuePtr outerVal = outer->property(it.key());
                if (Q_UNLIKELY(outerVal && outerVal->type() != Value::JSSourceValueType)) {
                    throw ErrorInfo(Tr::tr("Incompatible value type in unconditional value at %1.")
                                    .arg(outerVal->location().toString()));
                }
                doApply(it.key(), outer, std::static_pointer_cast<JSSourceValue>(outerVal),
                        std::static_pointer_cast<JSSourceValue>(it.value()));
            } else {
                QBS_CHECK(!"Unexpected value type in conditional value.");
            }
        }
    }

    void doApply(const QString &propertyName, Item *item, JSSourceValuePtr value,
               const JSSourceValuePtr &conditionalValue)
    {
        if (!value) {
            value = JSSourceValue::create(true);
            value->setFile(conditionalValue->file());
            item->setProperty(propertyName, value);
            value->setSourceCode(StringConstants::baseVar());
            value->setSourceUsesBase();
        }
        m_alternative.value = conditionalValue;
        value->addAlternative(m_alternative);
    }
};

static JSSourceValue::AltProperty getPropertyData(const Item *propertiesItem, const QString &name)
{
    const ValuePtr value = propertiesItem->property(name);
    if (!value) {
        if (name == StringConstants::conditionProperty()) {
            throw ErrorInfo(Tr::tr("Properties.condition must be provided."),
                            propertiesItem->location());
        }
        return {StringConstants::falseValue(), propertiesItem->location()};
    }
    if (Q_UNLIKELY(value->type() != Value::JSSourceValueType)) {
        throw ErrorInfo(Tr::tr("Properties.%1 must be a value binding.").arg(name),
                    propertiesItem->location());
    }
    if (name == StringConstants::overrideListPropertiesProperty()) {
        const Item *parent = propertiesItem->parent();
        while (parent) {
            if (parent->type() == ItemType::Product)
                break;
            parent = parent->parent();
        }
        if (!parent) {
            throw ErrorInfo(Tr::tr("Properties.overrideListProperties can only be set "
                                   "in a Product item."));
        }

    }
    const JSSourceValuePtr srcval = std::static_pointer_cast<JSSourceValue>(value);
    return {srcval->sourceCodeForEvaluation(), srcval->location()};
}

void ASTPropertiesItemHandler::handlePropertiesBlock(const Item *propertiesItem)
{
    const auto condition = getPropertyData(propertiesItem, StringConstants::conditionProperty());
    const auto overrideListProperties = getPropertyData(propertiesItem,
            StringConstants::overrideListPropertiesProperty());
    PropertiesBlockConverter(condition, overrideListProperties, m_parentItem,
                             propertiesItem, m_itemPool).apply();
}

} // namespace Internal
} // namespace qbs
