/**
 * Copyright: Copyright (c) 2011 Jacob Carlborg. All rights reserved.
 * Authors: Jacob Carlborg
 * Version: Initial created: Jan 29, 2012
 * License: $(LINK2 http://www.boost.org/LICENSE_1_0.txt, Boost Software License 1.0)
 */
module dstep.translator.objc.ObjcInterface;

import mambo.core._;

import clang.c.Index;
import clang.Cursor;
import clang.Type;
import clang.Util;
import clang.Visitor;

import dstep.translator.Translator;
import dstep.translator.Declaration;
import dstep.translator.Output;
import dstep.translator.Type;

class ObjcInterface (Data) : Declaration
{
    this (Cursor cursor, Cursor parent, Translator translator)
    {
        super(cursor, parent, translator);
    }

    override string translate ()
    {
        auto cursor = cursor.objc;

        return writeClass(spelling, cursor.superClass.spelling, collectInterfaces(cursor.objc), {
            foreach (cursor, parent ; cursor.declarations)
            {
                with (CXCursorKind)
                    switch (cursor.kind)
                    {
                        case CXCursor_ObjCInstanceMethodDecl: translateMethod(cursor.func); break;
                        case CXCursor_ObjCClassMethodDecl: translateMethod(cursor.func, true); break;
                        case CXCursor_ObjCPropertyDecl: translateProperty(cursor); break;
                        case CXCursor_ObjCIvarDecl: translateInstanceVariable(cursor); break;
                        default: break;
                    }
            }
        });
    }

    protected string[] collectInterfaces (ObjcCursor cursor)
    {
        string[] interfaces;

        foreach (cursor , parent ; cursor.protocols)
            interfaces ~= translateIdentifier(cursor.spelling);

        return interfaces;
    }

private:

    string writeClass (string name, string superClassName, string[] interfaces, void delegate () dg)
    {
        output.currentClass = new Data;
        output.currentClass.name = translateIdentifier(name);
        output.currentClass.interfaces = interfaces;

        if (superClassName.isPresent)
            output.currentClass.superclass ~= translateIdentifier(superClassName);

        dg();

        return output.currentClass.data;
    }

    void translateMethod (FunctionCursor func, bool classMethod = false, string name = null)
    {
        auto method = output.newContext();
        auto cls = output.currentClass;

        if (cls.propertyList.contains(func.spelling))
            return;

        name = cls.getMethodName(func, name, false);

        if (isGetter(func, name))
            translateGetter(func.resultType, method, name, cls, classMethod);

        else if (isSetter(func, name))
        {
            auto param = func.parameters.first;
            name = toDSetterName(name);
            translateSetter(param.type, method, name, cls, classMethod, param.spelling);
        }

        else
        {
            name = translateIdentifier(name);
            translateFunction(func, name, method, classMethod);

            method ~= ' ';
            writeSelector(method, func.spelling);
            method ~= ';';

            if (classMethod)
                cls.staticMethods ~= method.data;

            else
                cls.instanceMethods ~= method.data;
        }
    }

    void translateProperty (Cursor cursor)
    {
        auto context = output.newContext();
        auto cls = output.currentClass;
        auto name = cls.getMethodName(cursor.func, "", false);

        translateGetter(cursor.type, context, name, cls, false);
        context = output.newContext();
        translateSetter(cursor.type, context, name, cls, false);
    }

    void translateInstanceVariable (Cursor cursor)
    {
        auto var = output.newContext();
        translator.variable(cursor, var);
        output.currentClass.instanceVariables ~= var.data;
    }

    void translateGetter (Type type, String context, string name, ClassData cls, bool classMethod)
    {
        auto dName = name == "class" ? name : translateIdentifier(name);

        context ~= "@property ";

        if (classMethod)
            context ~= "static ";

        context ~= translateType(type);
        context ~= " ";
        context ~= dName;
        context ~= " () ";
        writeSelector(context, name);
        context ~= ';';

        auto data = context.data;

        if (classMethod)
            cls.staticProperties ~= data;

        else
            cls.properties ~= data;

        cls.propertyList.add(name);
    }

    void translateSetter (Type type, String context, string name, ClassData cls, bool classMethod, string parameterName = "")
    {
        auto selector = toObjcSetterName(name) ~ ':';

        context ~= "@property ";

        if (classMethod)
            context ~= "static ";

        context ~= "void ";
        context ~= translateIdentifier(name);
        context ~= " (";
        context ~= translateType(type);

        if (parameterName.any)
        {
            context ~= " ";
            context ~= parameterName;
        }

        context ~= ") ";
        writeSelector(context, selector);
        context ~= ';';

        auto data = context.data;

        if (classMethod)
            cls.staticProperties ~= data;

        else
            cls.properties ~= data;

        cls.propertyList.add(selector);
    }

    string toDSetterName (string name)
    {
        assert(isSetter(name));
        name = name[3 .. $];
        auto firstLetter = name[0 .. 1];
        auto r = firstLetter.toLower ~ name[1 .. $];
        return r.assumeUnique;
    }

    string toObjcSetterName (string name)
    {
        auto r = "set" ~ name[0 .. 1].toUpper ~ name[1 .. $];
        return r.assumeUnique;
    }

    bool isGetter (FunctionCursor cursor, string name)
    {
        return cursor.resultType.kind != CXTypeKind.CXType_Void && cursor.parameters.isEmpty;
    }

    bool isSetter (string name)
    {
        if (name.length > 3 && name.startsWith("set"))
        {
            auto firstLetter = name[3 .. $].first;
            return firstLetter.isUpper;
        }

        return false;
    }

    bool isSetter (FunctionCursor cursor, string name)
    {
        return isSetter(name) &&
            cursor.resultType.kind == CXTypeKind.CXType_Void &&
            cursor.parameters.length == 1;
    }

    void writeSelector (String context, string selector)
    {
        context.put(`@selector("`, selector, `")`);
    }
}