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#ifndef QMLJS_OBJECTS_H
#define QMLJS_OBJECTS_H

#include "qmljs_runtime.h"
#include "qv4array_p.h"
#include "qv4codegen_p.h"

#include <QtCore/QString>
#include <QtCore/QHash>
#include <QtCore/QRegularExpression>
#include <cstdio>
#include <cassert>
#include <setjmp.h>

namespace QQmlJS {

namespace IR {
struct Function;
}

namespace VM {

struct Value;
struct Object;
struct BooleanObject;
struct NumberObject;
struct StringObject;
struct ArrayObject;
struct DateObject;
struct FunctionObject;
struct RegExpObject;
struct ErrorObject;
struct ActivationObject;
struct ArgumentsObject;
struct Context;
struct ExecutionEngine;

struct ObjectPrototype;
struct StringPrototype;
struct NumberPrototype;
struct BooleanPrototype;
struct ArrayPrototype;
struct FunctionPrototype;
struct DatePrototype;
struct RegExpPrototype;
struct ErrorPrototype;
struct EvalErrorPrototype;
struct RangeErrorPrototype;
struct ReferenceErrorPrototype;
struct SyntaxErrorPrototype;
struct TypeErrorPrototype;
struct URIErrorPrototype;

struct String {
    String(const QString &text)
        : _text(text), _hashValue(0) {}

    inline bool isEqualTo(const String *other) const {
        if (this == other)
            return true;
        else if (other && hashValue() == other->hashValue())
            return toQString() == other->toQString();
        return false;
    }

    inline const QString &toQString() const {
        return _text;
    }

    inline unsigned hashValue() const {
        if (! _hashValue)
            _hashValue = qHash(_text);

        return _hashValue;
    }

private:
    QString _text;
    mutable unsigned _hashValue;
};

struct PropertyDescriptor {
    enum Type {
        Generic,
        Data,
        Accessor
    };
    enum State {
        Undefined,
        Unset,
        Set
    };
    union {
        Value value;
        struct {
            FunctionObject *get;
            FunctionObject *set;
        };
    };
    uint type : 8;
    uint writable : 8;
    uint enumberable : 8;
    uint configurable : 8;

    static inline PropertyDescriptor fromValue(Value v) {
        PropertyDescriptor pd;
        pd.value = v;
        pd.type = Data;
        pd.writable = Undefined;
        pd.enumberable = Undefined;
        pd.configurable = Undefined;
        return pd;
    }
    static inline PropertyDescriptor fromAccessor(FunctionObject *getter, FunctionObject *setter) {
        PropertyDescriptor pd;
        pd.get = getter;
        pd.set = setter;
        pd.type = Accessor;
        pd.writable = Undefined;
        pd.enumberable = Undefined;
        pd.configurable = Undefined;
        return pd;
    }

    // Section 8.10
    inline void fullyPopulated() {
        if (type == Generic) {
            type = Data;
            value = Value::undefinedValue();
        }
        if (type == Data) {
            if (writable == Undefined)
                writable = Unset;
        } else {
            writable = Undefined;
        }
        if (enumberable == Undefined)
            enumberable = Unset;
        if (configurable == Undefined)
            configurable = Unset;
    }

    inline bool isData() const { return type == Data; }
    inline bool isAccessor() const { return type == Accessor; }
    inline bool isGeneric() const { return type == Generic; }

    inline bool isWritable() const { return writable == Set; }
    inline bool isEnumerable() const { return enumberable == Set; }
    inline bool isConfigurable() const { return configurable == Set; }

    inline bool isEmpty() {
        return type == Generic && writable == Undefined && enumberable == Undefined && configurable == Undefined;
    }
    inline bool isSubset(PropertyDescriptor *other) {
        if (type != other->type)
            return false;
        if (enumberable != Undefined && enumberable != other->enumberable)
            return false;
        if (configurable != Undefined && configurable != other->configurable)
            return false;
        if (writable != Undefined && writable != other->writable)
            return false;
        if (type == Data && !value.sameValue(other->value))
            return false;
        if (type == Accessor && (get != other->get || set != other->set))
            return false;
        return true;
    }
    inline void operator+=(const PropertyDescriptor &other) {
        type = other.type;
        if (other.enumberable != Undefined)
            enumberable = other.enumberable;
        if (other.configurable != Undefined)
            configurable = other.configurable;
        if (other.writable != Undefined)
            writable = other.writable;
        if (type == Accessor) {
            get = other.get;
            set = other.set;
        } else {
            value = other.value;
        }
    }
};

struct PropertyTableEntry {
    PropertyDescriptor descriptor;
    String *name;
    PropertyTableEntry *next;
    int index;

    inline PropertyTableEntry(String *name)
        : name(name),
          next(0),
          index(-1)
    { }

    inline bool hasName(String *n) const { return name->isEqualTo(n); }
    inline unsigned hashValue() const { return name->hashValue(); }
};

class PropertyTable
{
    Q_DISABLE_COPY(PropertyTable)

public:
    PropertyTable()
        : _properties(0)
        , _buckets(0)
        , _freeList(0)
        , _propertyCount(-1)
        , _bucketCount(0)
        , _allocated(0) {}

    ~PropertyTable()
    {
        qDeleteAll(_properties, _properties + _propertyCount + 1);
        delete[] _properties;
        delete[] _buckets;
    }

    inline bool isEmpty() const { return _propertyCount == -1; }

    typedef PropertyTableEntry **iterator;
    inline iterator begin() const { return _properties; }
    inline iterator end() const { return _properties + (_propertyCount + 1); }

    void remove(PropertyTableEntry *prop)
    {
        PropertyTableEntry **bucket = _buckets + (prop->hashValue() % _bucketCount);
        if (*bucket == prop) {
            *bucket = prop->next;
        } else {
            for (PropertyTableEntry *it = *bucket; it; it = it->next) {
                if (it->next == prop) {
                    it->next = it->next->next;
                    break;
                }
            }
        }

        _properties[prop->index] = 0;
        prop->next = _freeList;
        _freeList = prop;
    }

    PropertyTableEntry *findEntry(String *name) const
    {
        if (_properties) {
            for (PropertyTableEntry *prop = _buckets[name->hashValue() % _bucketCount]; prop; prop = prop->next) {
                if (prop && (prop->name == name || prop->hasName(name)))
                    return prop;
            }
        }

        return 0;
    }

    PropertyDescriptor *find(String *name) const
    {
        if (_properties) {
            for (PropertyTableEntry *prop = _buckets[name->hashValue() % _bucketCount]; prop; prop = prop->next) {
                if (prop && (prop->name == name || prop->hasName(name)))
                    return &prop->descriptor;
            }
        }

        return 0;
    }

    PropertyDescriptor *insert(String *name)
    {
        if (PropertyTableEntry *prop = findEntry(name))
            return &prop->descriptor;

        if (++_propertyCount == _allocated) {
            if (! _allocated)
                _allocated = 4;
            else
                _allocated *= 2;

            PropertyTableEntry **properties = new PropertyTableEntry*[_allocated];
            std::copy(_properties, _properties + _propertyCount, properties);
            delete[] _properties;
            _properties = properties;
        }

        PropertyTableEntry *prop;
        if (_freeList) {
            prop = _freeList;
            _freeList = _freeList->next;
        } else {
            prop = new PropertyTableEntry(name);
        }

        prop->index = _propertyCount;
        _properties[_propertyCount] = prop;

        if (! _buckets || 3 * _propertyCount >= 2 * _bucketCount) {
            rehash();
        } else {
            PropertyTableEntry *&bucket = _buckets[prop->hashValue() % _bucketCount];
            prop->next = bucket;
            bucket = prop;
        }

        return &prop->descriptor;
    }

private:
    void rehash()
    {
        if (_bucketCount)
            _bucketCount = _bucketCount * 2 + 1; // ### next prime
        else
            _bucketCount = 11;

        delete[] _buckets;
        _buckets = new PropertyTableEntry *[_bucketCount];
        std::fill(_buckets, _buckets + _bucketCount, (PropertyTableEntry *) 0);

        for (int i = 0; i <= _propertyCount; ++i) {
            PropertyTableEntry *prop = _properties[i];
            PropertyTableEntry *&bucket = _buckets[prop->hashValue() % _bucketCount];
            prop->next = bucket;
            bucket = prop;
        }
    }

private:
    friend struct ForEachIteratorObject;
    PropertyTableEntry **_properties;
    PropertyTableEntry **_buckets;
    PropertyTableEntry *_freeList;
    int _propertyCount;
    int _bucketCount;
    int _allocated;
};

struct Object {
    Object *prototype;
    String *klass;
    PropertyTable *members;
    bool extensible;

    Object()
        : prototype(0)
        , klass(0)
        , members(0)
        , extensible(true) {}

    virtual ~Object();

    virtual QString className() { return QStringLiteral("Object"); }
    virtual BooleanObject *asBooleanObject() { return 0; }
    virtual NumberObject *asNumberObject() { return 0; }
    virtual StringObject *asStringObject() { return 0; }
    virtual DateObject *asDateObject() { return 0; }
    virtual ArrayObject *asArrayObject() { return 0; }
    virtual FunctionObject *asFunctionObject() { return 0; }
    virtual RegExpObject *asRegExpObject() { return 0; }
    virtual ErrorObject *asErrorObject() { return 0; }
    virtual ActivationObject *asActivationObject() { return 0; }
    virtual ArgumentsObject *asArgumentsObject() { return 0; }

    virtual Value __get__(Context *ctx, String *name);
    virtual PropertyDescriptor *__getOwnProperty__(Context *ctx, String *name);
    virtual PropertyDescriptor *__getPropertyDescriptor__(Context *ctx, String *name, PropertyDescriptor *to_fill);
    virtual void __put__(Context *ctx, String *name, const Value &value, bool throwException = false);
    virtual bool __canPut__(Context *ctx, String *name);
    virtual bool __hasProperty__(Context *ctx, String *name) const;
    virtual bool __delete__(Context *ctx, String *name, bool throwException);
    virtual bool __defineOwnProperty__(Context *ctx, String *name, PropertyDescriptor *desc, bool throwException = false);

    //
    // helpers
    //
    void __put__(Context *ctx, const QString &name, const Value &value);
    void __put__(Context *ctx, const QString &name, void (*code)(Context *), int count = 0);

    Value getValue(Context *ctx, PropertyDescriptor *p) const;
    bool inplaceBinOp(Value rhs, String *name, BinOp op, Context *ctx);
    virtual bool inplaceBinOp(Value rhs, Value index, BinOp op, Context *ctx);
};

struct ForEachIteratorObject: Object {
    Object *object;
    Object *current; // inside the prototype chain
    int tableIndex;
    ForEachIteratorObject(Object *o) : object(o), current(o), tableIndex(-1) {}
    virtual QString className() { return QStringLiteral("__ForEachIteratorObject"); }

    String *nextPropertyName();
};

struct BooleanObject: Object {
    Value value;
    BooleanObject(const Value &value): value(value) {}
    virtual QString className() { return QStringLiteral("Boolean"); }
    virtual BooleanObject *asBooleanObject() { return this; }
};

struct NumberObject: Object {
    Value value;
    NumberObject(const Value &value): value(value) {}
    virtual QString className() { return QStringLiteral("Number"); }
    virtual NumberObject *asNumberObject() { return this; }
};

struct StringObject: Object {
    Value value;
    StringObject(const Value &value): value(value) {}
    virtual QString className() { return QStringLiteral("String"); }
    virtual StringObject *asStringObject() { return this; }
};

struct DateObject: Object {
    Value value;
    DateObject(const Value &value): value(value) {}
    virtual QString className() { return QStringLiteral("Date"); }
    virtual DateObject *asDateObject() { return this; }
};

struct ArrayObject: Object {
    Array value;
    ArrayObject() {}
    ArrayObject(const Array &value): value(value) {}
    virtual QString className() { return QStringLiteral("Array"); }
    virtual ArrayObject *asArrayObject() { return this; }
    virtual Value __get__(Context *ctx, String *name);

    virtual bool inplaceBinOp(Value rhs, Value index, BinOp op, Context *ctx);
};

struct FunctionObject: Object {
    Context *scope;
    String *name;
    String **formalParameterList;
    unsigned int formalParameterCount;
    String **varList;
    unsigned int varCount;
    bool needsActivation;

    FunctionObject(Context *scope)
        : scope(scope)
        , name(0)
        , formalParameterList(0)
        , formalParameterCount(0)
        , varList(0)
        , varCount(0)
        , needsActivation(false) {}

    virtual QString className() { return QStringLiteral("Function"); }
    virtual FunctionObject *asFunctionObject() { return this; }
    virtual bool hasInstance(Context *ctx, const Value &value);

    Value construct(Context *context, Value *args, int argc);
    virtual Value call(Context *context, Value thisObject, Value *args, int argc, bool strictMode = false);

protected:
    virtual void call(Context *ctx);
    virtual void construct(Context *ctx);
};

struct NativeFunction: FunctionObject {
    void (*code)(Context *);

    NativeFunction(Context *scope, void (*code)(Context *)): FunctionObject(scope), code(code) {}
    virtual void call(Context *ctx) { code(ctx); }
    virtual void construct(Context *ctx) { code(ctx); }
};

struct ScriptFunction: FunctionObject {
    IR::Function *function;

    ScriptFunction(Context *scope, IR::Function *function);
    virtual ~ScriptFunction();

    virtual void call(Context *ctx);
    virtual void construct(Context *ctx);
};

struct EvalFunction : FunctionObject
{
    EvalFunction(Context *scope): FunctionObject(scope) {}

    static int evaluate(QQmlJS::VM::Context *ctx, const QString &fileName,
                        const QString &source, bool useInterpreter,
                        QQmlJS::Codegen::Mode mode);

    virtual Value call(Context *context, Value thisObject, Value *args, int argc, bool strictMode = false);
};

struct RegExpObject: Object {
    QRegularExpression value;
    Value lastIndex;
    bool global;
    RegExpObject(const QRegularExpression &value, bool global): value(value), lastIndex(Value::fromInt32(0)), global(global) {}
    virtual QString className() { return QStringLiteral("RegExp"); }
    virtual RegExpObject *asRegExpObject() { return this; }
    virtual Value __get__(Context *ctx, String *name);
};

struct ErrorObject: Object {
    Value value;
    ErrorObject(const Value &message): value(message) {}
    virtual QString className() { return QStringLiteral("Error"); }
    virtual ErrorObject *asErrorObject() { return this; }
    virtual Value __get__(Context *ctx, String *name);

protected:
    void setNameProperty(Context *ctx);
};

struct EvalErrorObject: ErrorObject {
    EvalErrorObject(Context *ctx): ErrorObject(ctx->argument(0)) { setNameProperty(ctx); }
    virtual QString className() { return QStringLiteral("EvalError"); }
};

struct RangeErrorObject: ErrorObject {
    RangeErrorObject(Context *ctx): ErrorObject(ctx->argument(0)) { setNameProperty(ctx); }
    virtual QString className() { return QStringLiteral("RangeError"); }
};

struct ReferenceErrorObject: ErrorObject {
    ReferenceErrorObject(Context *ctx): ErrorObject(ctx->argument(0)) { setNameProperty(ctx); }
    virtual QString className() { return QStringLiteral("ReferenceError"); }
};

struct SyntaxErrorObject: ErrorObject {
    SyntaxErrorObject(Context *ctx): ErrorObject(ctx->argument(0)) { setNameProperty(ctx); }
    virtual QString className() { return QStringLiteral("SyntaxError"); }
};

struct TypeErrorObject: ErrorObject {
    TypeErrorObject(Context *ctx): ErrorObject(ctx->argument(0)) { setNameProperty(ctx); }
    virtual QString className() { return QStringLiteral("TypeError"); }
};

struct URIErrorObject: ErrorObject {
    URIErrorObject(Context *ctx): ErrorObject(ctx->argument(0)) { setNameProperty(ctx); }
    virtual QString className() { return QStringLiteral("URIError"); }
};

struct ActivationObject: Object {
    Context *context;
    Value arguments;
    ActivationObject(Context *context): context(context), arguments(Value::undefinedValue()) {}
    virtual QString className() { return QStringLiteral("Activation"); }
    virtual ActivationObject *asActivationObject() { return this; }
    virtual PropertyDescriptor *__getPropertyDescriptor__(Context *ctx, String *name, PropertyDescriptor *to_fill);
};

struct ArgumentsObject: Object {
    Context *context;
    ArgumentsObject(Context *context): context(context) {}
    virtual QString className() { return QStringLiteral("Arguments"); }
    virtual ArgumentsObject *asArgumentsObject() { return this; }
    virtual Value __get__(Context *ctx, String *name);
    virtual PropertyDescriptor *__getPropertyDescriptor__(Context *ctx, String *name, PropertyDescriptor *to_fill);
};

struct ExecutionEngine
{
    Context *rootContext;
    Value globalObject;

    Value objectCtor;
    Value stringCtor;
    Value numberCtor;
    Value booleanCtor;
    Value arrayCtor;
    Value functionCtor;
    Value dateCtor;
    Value regExpCtor;
    Value errorCtor;
    Value evalErrorCtor;
    Value rangeErrorCtor;
    Value referenceErrorCtor;
    Value syntaxErrorCtor;
    Value typeErrorCtor;
    Value uRIErrorCtor;

    ObjectPrototype *objectPrototype;
    StringPrototype *stringPrototype;
    NumberPrototype *numberPrototype;
    BooleanPrototype *booleanPrototype;
    ArrayPrototype *arrayPrototype;
    FunctionPrototype *functionPrototype;
    DatePrototype *datePrototype;
    RegExpPrototype *regExpPrototype;
    ErrorPrototype *errorPrototype;
    EvalErrorPrototype *evalErrorPrototype;
    RangeErrorPrototype *rangeErrorPrototype;
    ReferenceErrorPrototype *referenceErrorPrototype;
    SyntaxErrorPrototype *syntaxErrorPrototype;
    TypeErrorPrototype *typeErrorPrototype;
    URIErrorPrototype *uRIErrorPrototype;

    QHash<QString, String *> identifiers;

    String *id_length;
    String *id_prototype;
    String *id_constructor;
    String *id_arguments;
    String *id___proto__;

    struct ExceptionHandler {
        Context *context;
        const uchar *code; // Interpreter state
        int targetTempIndex; // Interpreter state
        jmp_buf stackFrame;
    };

    QVector<ExceptionHandler> unwindStack;

    ExecutionEngine();

    Context *newContext();

    String *identifier(const QString &s);

    FunctionObject *newNativeFunction(Context *scope, void (*code)(Context *));
    FunctionObject *newScriptFunction(Context *scope, IR::Function *function);

    Object *newObject();
    FunctionObject *newObjectCtor(Context *ctx);

    String *newString(const QString &s);
    Object *newStringObject(const Value &value);
    FunctionObject *newStringCtor(Context *ctx);

    Object *newNumberObject(const Value &value);
    FunctionObject *newNumberCtor(Context *ctx);

    Object *newBooleanObject(const Value &value);
    FunctionObject *newBooleanCtor(Context *ctx);

    Object *newFunctionObject(Context *ctx);
    FunctionObject *newFunctionCtor(Context *ctx);

    Object *newArrayObject();
    Object *newArrayObject(const Array &value);
    FunctionObject *newArrayCtor(Context *ctx);

    Object *newDateObject(const Value &value);
    FunctionObject *newDateCtor(Context *ctx);

    Object *newRegExpObject(const QString &pattern, int flags);
    FunctionObject *newRegExpCtor(Context *ctx);

    Object *newErrorObject(const Value &value);
    Object *newMathObject(Context *ctx);
    Object *newActivationObject(Context *ctx);

    Object *newForEachIteratorObject(Object *o);
};

} // namespace VM
} // namespace QQmlJS

#endif // QMLJS_OBJECTS_H