// mono
extern "C" {
#include <mono/jit/jit.h>
#include <mono/metadata/object.h>
#include <mono/metadata/environment.h>
#include <mono/metadata/assembly.h>
#include <mono/metadata/debug-helpers.h>
#include <mono/metadata/class.h>
#include <mono/metadata/metadata.h>
}

#ifdef _MSC_VER
#pragma warning(disable: 4091)
#endif
#include <m_pd.h>

#include <assert.h>
#include <stdlib.h>
#include <string.h>

#ifdef _WIN32
#include <io.h> // for _close
#define close _close
#else
#include <unistd.h>
#endif

#include <map>

#define CORELIB "PureData"
#define DLLEXT "dll"


// cached mono data

static MonoDomain *monodomain;
static MonoClass *clr_symbol,*clr_pointer,*clr_atom,*clr_atomlist,*clr_external;
static MonoMethodDesc *clr_desc_tostring,*clr_desc_ctor;
static MonoMethod *clr_meth_invoke;
static MonoProperty *clr_prop_method;


struct AtomList
{
    int argc;
    t_atom *argv;

    void Set(int c,t_atom *v) { argc = c,argv = v; }
};


// temporary workspace items

static MonoArray *clr_objarr_1,*clr_objarr_2;
static MonoObject *clr_obj_single,*clr_obj_symbol,*clr_obj_pointer,*clr_obj_atomlist;
static float *clr_val_single;
static t_symbol **clr_val_symbol;
static void **clr_val_pointer;
static AtomList *clr_val_atomlist;



struct Delegate
{
    operator bool() const { return methodinfo != NULL; }

    MonoObject *methodinfo;
    MonoMethod *virtmethod;
};

typedef std::map<t_symbol *,Delegate> ClrMethodMap;


// this is the class structure
// holding the pd and mono class
// and our CLR method pointers
struct t_clr_class
{
    t_class *pd_class;
    MonoClass *mono_class;
    MonoClassField *mono_obj_field;
    MonoMethod *mono_ctor;
    t_symbol *name;
    Delegate method_bang,method_float,method_symbol,method_pointer,method_list,method_anything;
    ClrMethodMap *methods; // explicit method selectors
};

typedef std::map<t_symbol *,t_clr_class *> ClrMap;
// this holds the class name to class structure association
static ClrMap clr_map;

// this is the class to be setup (while we are in the CLR static Main method)
static t_clr_class *clr_setup_class = NULL;

// this is the class instance object structure
struct t_clr
{
    t_object pd_obj; // myself
    t_clr_class *clr_clss; // pointer to our class structure
    MonoObject *mono_obj;  // the mono class instance
};



// Print error message given by exception
static void error_exc(char *txt,char *cname,MonoObject *exc)
{
    MonoMethod *m = mono_method_desc_search_in_class(clr_desc_tostring,mono_get_exception_class());
    assert(m);
    m = mono_object_get_virtual_method(exc,m);
    assert(m);
    MonoString *str = (MonoString *)mono_runtime_invoke(m,exc,NULL,NULL);
    assert(str);
    error("CLR class %s: %s",txt,cname);
    error(mono_string_to_utf8(str));
}

static void clr_method_bang(t_clr *x) 
{
    assert(x && x->clr_clss);

    const Delegate &d = x->clr_clss->method_bang;
    assert(d);

    gpointer args[2] = {x->mono_obj,NULL};
    MonoObject *exc;
    mono_runtime_invoke(d.virtmethod,d.methodinfo,args,&exc);
    if(exc) error_exc("Exception raised",x->clr_clss->name->s_name,exc);
}

static void clr_method_float(t_clr *x,t_float f) 
{
    assert(x && x->clr_clss);

    const Delegate &d = x->clr_clss->method_float;
    assert(d);

    *clr_val_single = f;
    mono_array_set(clr_objarr_1,void*,0,clr_obj_single);

    gpointer args[2] = {x->mono_obj,clr_objarr_1};
    MonoObject *exc;
    mono_runtime_invoke(d.virtmethod,d.methodinfo,args,&exc);
    if(exc) error_exc("Exception raised",x->clr_clss->name->s_name,exc);
}

static void clr_method_symbol(t_clr *x,t_symbol *s) 
{
    assert(x && x->clr_clss);

    const Delegate &d = x->clr_clss->method_symbol;
    assert(d);

    *clr_val_symbol = s;
    mono_array_set(clr_objarr_1,void*,0,clr_obj_symbol);

    gpointer args[2] = {x->mono_obj,clr_objarr_1};
    MonoObject *exc;
    mono_runtime_invoke(d.virtmethod,d.methodinfo,args,&exc);
    if(exc) error_exc("Exception raised",x->clr_clss->name->s_name,exc);
}

static void clr_method_pointer(t_clr *x,t_gpointer *p)
{
    assert(x && x->clr_clss);

    const Delegate &d = x->clr_clss->method_pointer;
    assert(d);

    *clr_val_pointer = p;
    mono_array_set(clr_objarr_1,void*,0,clr_obj_pointer);

    gpointer args[2] = {x->mono_obj,clr_objarr_1};
    MonoObject *exc;
    mono_runtime_invoke(d.virtmethod,d.methodinfo,args,&exc);
    if(exc) error_exc("Exception raised",x->clr_clss->name->s_name,exc);
}


static void clr_method_list(t_clr *x,t_symbol *l, int argc, t_atom *argv)
{
    assert(x && x->clr_clss);

    const Delegate &d = x->clr_clss->method_list;
    assert(d);

    clr_val_atomlist->Set(argc,argv);
    mono_array_set(clr_objarr_1,void*,0,clr_obj_atomlist);

    gpointer args[2] = {x->mono_obj,clr_objarr_1};
    MonoObject *exc;
    mono_runtime_invoke(d.virtmethod,d.methodinfo,args,&exc);
    if(exc) error_exc("Exception raised",x->clr_clss->name->s_name,exc);
}

static void clr_method_anything(t_clr *x,t_symbol *s,int argc,t_atom *argv)
{
    assert(x && x->clr_clss);

    const Delegate *d = NULL;
    ClrMethodMap *methods = x->clr_clss->methods;
    if(methods) {
        ClrMethodMap::iterator it = methods->find(s);
        if(it != methods->end()) d = &it->second;
    }

    gpointer args[2];
    args[0] = x->mono_obj;

    if(d) {
        // explicit selector

        clr_val_atomlist->Set(argc,argv);
        mono_array_set(clr_objarr_1,void*,0,clr_obj_atomlist);
        args[1] = clr_objarr_1;
    }
    else {
        // general method

        d = &x->clr_clss->method_anything;
        assert(d);

        *clr_val_symbol = s;
        clr_val_atomlist->Set(argc,argv);
        mono_array_set(clr_objarr_2,void*,0,clr_obj_symbol);
        mono_array_set(clr_objarr_2,void*,1,clr_obj_atomlist);
        args[1] = clr_objarr_2;
    }

    MonoObject *exc;
    mono_runtime_invoke(d->virtmethod,d->methodinfo,args,&exc);
    if(exc) error_exc("Exception raised",x->clr_clss->name->s_name,exc);
}

// this function is called by mono when it wants post messages to pd
static void PD_Post(MonoString *str)
{
	post("%s",mono_string_to_utf8(str));	
}

// this function is called by mono when it wants post messages to pd
static void PD_PostError(MonoString *str)
{
	error("%s",mono_string_to_utf8(str));	
}

// this function is called by mono when it wants post messages to pd
static void PD_PostBug(MonoString *str)
{
	bug("%s",mono_string_to_utf8(str));	
}

// this function is called by mono when it wants post messages to pd
static void PD_PostVerbose(int lvl,MonoString *str)
{
	verbose(lvl,"%s",mono_string_to_utf8(str));	
}

static void *PD_SymGen(MonoString *str)
{
    assert(str);
	return gensym(mono_string_to_utf8(str));	
}

static MonoString *PD_SymEval(t_symbol *sym)
{
    assert(sym);
    return mono_string_new(monodomain,sym->s_name);
}

static void PD_AddBang(MonoObject *method)
{
    assert(clr_setup_class);
    Delegate &d = clr_setup_class->method_bang;
    d.methodinfo = mono_property_get_value(clr_prop_method,method,NULL,NULL);
    d.virtmethod = mono_object_get_virtual_method(d.methodinfo,clr_meth_invoke);
}

static void PD_AddFloat(MonoObject *method)
{
    assert(clr_setup_class);
    Delegate &d = clr_setup_class->method_float;
    d.methodinfo = mono_property_get_value(clr_prop_method,method,NULL,NULL);
    d.virtmethod = mono_object_get_virtual_method(d.methodinfo,clr_meth_invoke);
}

static void PD_AddSymbol(MonoObject *method)
{
    assert(clr_setup_class);
    Delegate &d = clr_setup_class->method_symbol;
    d.methodinfo = mono_property_get_value(clr_prop_method,method,NULL,NULL);
    d.virtmethod = mono_object_get_virtual_method(d.methodinfo,clr_meth_invoke);
}

static void PD_AddPointer(MonoObject *method)
{
    assert(clr_setup_class);
    Delegate &d = clr_setup_class->method_pointer;
    d.methodinfo = mono_property_get_value(clr_prop_method,method,NULL,NULL);
    d.virtmethod = mono_object_get_virtual_method(d.methodinfo,clr_meth_invoke);
}

static void PD_AddList(MonoObject *method)
{
    assert(clr_setup_class);
    Delegate &d = clr_setup_class->method_list;
    d.methodinfo = mono_property_get_value(clr_prop_method,method,NULL,NULL);
    d.virtmethod = mono_object_get_virtual_method(d.methodinfo,clr_meth_invoke);
}

static void PD_AddSelector(t_symbol *sym,MonoObject *method)
{
    assert(clr_setup_class);
    Delegate d;
    d.methodinfo = mono_property_get_value(clr_prop_method,method,NULL,NULL);
    d.virtmethod = mono_object_get_virtual_method(d.methodinfo,clr_meth_invoke);

    if(!clr_setup_class->methods)
        clr_setup_class->methods = new ClrMethodMap;
    // add tag to map
    (*clr_setup_class->methods)[sym] = d;
}

static void PD_AddAnything(MonoObject *method)
{
    assert(clr_setup_class);
    Delegate &d = clr_setup_class->method_anything;
    d.methodinfo = mono_property_get_value(clr_prop_method,method,NULL,NULL);
    d.virtmethod = mono_object_get_virtual_method(d.methodinfo,clr_meth_invoke);
}


void *clr_new(t_symbol *classname, int argc, t_atom *argv)
{
    // find class name in map
    ClrMap::iterator it = clr_map.find(classname);
    if(it == clr_map.end()) {
        error("CLR class %s not found",classname->s_name);
        return NULL;
    }

    t_clr_class *clss = it->second;

    // make instance
    t_clr *x = (t_clr *)pd_new(clss->pd_class);
    x->mono_obj = mono_object_new (monodomain,clss->mono_class);
    if(!x->mono_obj) {
        pd_free((t_pd *)x);
        error("CLR class %s could not be instantiated",classname->s_name);
        return NULL;
    }

    // store class pointer
    x->clr_clss = clss;
    x->clr_clss->name = classname;

    // store our object pointer in External::ptr member
    mono_field_set_value(x->mono_obj,clss->mono_obj_field,&x);

    // ok, we have an object - look for constructor
	if(clss->mono_ctor) {
    	AtomList al; 
        al.Set(argc,argv);
	    gpointer args = &al;

        // call constructor
        MonoObject *exc;
        mono_runtime_invoke(clss->mono_ctor,x->mono_obj,&args,&exc);

        if(exc) {
            pd_free((t_pd *)x);
            error_exc("exception raised in constructor",classname->s_name,exc);
            return NULL;
        }
    }
    else
        verbose(1,"CLR - Warning: no constructor for class %s found",classname->s_name);

    return x;
}

void clr_free(t_clr *x)
{
}

static int classloader(char *dirname, char *classname)
{
    t_clr_class *clr_class = NULL;
    t_symbol *classsym;
    MonoAssembly *assembly;
    MonoImage *image;
    MonoMethod *method;

    char dirbuf[MAXPDSTRING],*nameptr;
    // search for classname.dll in the PD path
    int fd;
    if ((fd = open_via_path(dirname, classname, "." DLLEXT, dirbuf, &nameptr, MAXPDSTRING, 1)) < 0)
        // not found
        goto bailout;

    // found
    close(fd);

    clr_class = (t_clr_class *)getbytes(sizeof(t_clr_class));
    memset(clr_class,0,sizeof(*clr_class));

//    clr_class->methods = NULL;

    // try to load assembly
    strcat(dirbuf,"/");
    strcat(dirbuf,classname);
    strcat(dirbuf,"." DLLEXT);

    assembly = mono_domain_assembly_open(monodomain,dirbuf);
	if(!assembly) {
		error("clr: file %s couldn't be loaded!",dirbuf);
		goto bailout;
	}

    image = mono_assembly_get_image(assembly);
    assert(image);

    // try to find class
    // "" means no namespace
	clr_class->mono_class = mono_class_from_name(image,"",classname);
	if(!clr_class->mono_class) {
		error("Can't find %s class in %s\n",classname,mono_image_get_filename(image));
		goto bailout;
	}

    clr_class->mono_obj_field = mono_class_get_field_from_name(clr_class->mono_class,"ptr");
    assert(clr_class->mono_obj_field);

    // make new class (with classname)
    classsym = gensym(classname);
    clr_class->pd_class = class_new(classsym,(t_newmethod)clr_new,(t_method)clr_free, sizeof(t_clr), CLASS_DEFAULT, A_GIMME, 0);

    // find static Main method

    MonoMethodDesc *clr_desc_main = mono_method_desc_new("::Setup",FALSE);
    assert(clr_desc_main);

    method = mono_method_desc_search_in_class(clr_desc_main,clr_class->mono_class);
	if(method) {
        MonoObject *obj = mono_object_new(monodomain,clr_class->mono_class);
        if(!obj) {
            error("CLR class %s could not be instantiated",classname);
            goto bailout;
        }

        // store NULL in External::ptr member
        void *x = NULL;
        mono_field_set_value(obj,clr_class->mono_obj_field,&x);

        // set current class
        clr_setup_class = clr_class;

        // call static Main method
	    gpointer args = obj;
        MonoObject *exc;
        mono_runtime_invoke(method,NULL,&args,&exc);

        // unset current class
        clr_setup_class = NULL;

        if(exc) {
            error_exc("CLR - Exception raised by Setup",classname,exc);
            goto bailout;
        }
    }
    else
        post("CLR - Warning: no %s.Setup method found",classname);

    // find and save constructor
    clr_class->mono_ctor = mono_method_desc_search_in_class(clr_desc_ctor,clr_class->mono_class);

    // find && register methods
    if(clr_class->method_bang)
        class_addbang(clr_class->pd_class,clr_method_bang);
    if(clr_class->method_float)
        class_addfloat(clr_class->pd_class,clr_method_float);
    if(clr_class->method_symbol)
        class_addsymbol(clr_class->pd_class,clr_method_symbol);
    if(clr_class->method_pointer)
        class_addpointer(clr_class->pd_class,clr_method_pointer);
    if(clr_class->method_list)
        class_addlist(clr_class->pd_class,clr_method_list);
    if(clr_class->method_anything || clr_class->methods)
        class_addanything(clr_class->pd_class,clr_method_anything);

    // put into map
    clr_map[classsym] = clr_class;

    verbose(1,"CLR - Loaded class %s OK",classname);

    return 1;

bailout:
    if(clr_class) freebytes(clr_class,sizeof(t_clr_class));

    return 0;
}

extern "C"
#ifdef _MSC_VER
__declspec(dllexport) 
#endif
void clr_setup(void)
{
#ifdef _WIN32
    // set mono paths
    const char *monopath = getenv("MONO_PATH");
    if(!monopath) {
        error("CLR - Please set the MONO_PATH environment variable to the folder of your MONO installation - CLR not loaded!");
        return;
    }
    
    char tlib[256],tconf[256];
    strcpy(tlib,monopath);
    strcat(tlib,"/lib");
    strcpy(tconf,monopath);
    strcat(tconf,"/etc");
    mono_set_dirs(tlib,tconf);
#endif

    try { 
        monodomain = mono_jit_init(CORELIB); 
    }
    catch(...) {
        monodomain = NULL;
    }

	if(monodomain) {
        // try to find PureData.dll in the PD path
        char dirbuf[MAXPDSTRING],*nameptr;
        // search for classname.dll in the PD path
        int fd;
        if ((fd = open_via_path("",CORELIB,"." DLLEXT,dirbuf,&nameptr,MAXPDSTRING,1)) >= 0) {
            strcat(dirbuf,"/" CORELIB "." DLLEXT);
            close(fd);
        }
        else 
            strcpy(dirbuf,CORELIB "." DLLEXT);

        // look for PureData.dll
        MonoAssembly *assembly = mono_domain_assembly_open (monodomain,dirbuf);
	    if(!assembly) {
		    error("clr: assembly " CORELIB "." DLLEXT " not found!");
		    return;
	    }

	    MonoImage *image = mono_assembly_get_image(assembly);
        assert(image);

	    // add mono to C hooks

        mono_add_internal_call("PureData.Internal::SymGen(string)", (const void *)PD_SymGen);
        mono_add_internal_call("PureData.Internal::SymEval(void*)", (const void *)PD_SymEval);

        mono_add_internal_call("PureData.External::Post(string)",(const void *)PD_Post);
        mono_add_internal_call("PureData.External::PostError(string)",(const void *)PD_PostError);
        mono_add_internal_call("PureData.External::PostBug(string)",(const void *)PD_PostBug);
        mono_add_internal_call("PureData.External::PostVerbose(string)",(const void *)PD_PostVerbose);

        mono_add_internal_call("PureData.External::Add(PureData.External/MethodBang)", (const void *)PD_AddBang);
        mono_add_internal_call("PureData.External::Add(PureData.External/MethodFloat)", (const void *)PD_AddFloat);
        mono_add_internal_call("PureData.External::Add(PureData.External/MethodSymbol)", (const void *)PD_AddSymbol);
        mono_add_internal_call("PureData.External::Add(PureData.External/MethodPointer)", (const void *)PD_AddPointer);
        mono_add_internal_call("PureData.External::Add(PureData.External/MethodList)", (const void *)PD_AddList);
        mono_add_internal_call("PureData.External::Add(PureData.Symbol,PureData.External/MethodList)", (const void *)PD_AddSelector);
        mono_add_internal_call("PureData.External::Add(PureData.External/MethodAnything)", (const void *)PD_AddAnything);

        // load important classes
        clr_symbol = mono_class_from_name(image,"PureData","Symbol");
        assert(clr_symbol);
        clr_pointer = mono_class_from_name(image,"PureData","Pointer");
        assert(clr_pointer);
        clr_atom = mono_class_from_name(image,"PureData","Atom");
        assert(clr_atom);
        clr_atomlist = mono_class_from_name(image,"PureData","AtomList");
        assert(clr_atomlist);
        clr_external = mono_class_from_name(image,"PureData","External");
        assert(clr_external);

        clr_desc_tostring = mono_method_desc_new("::ToString()",FALSE);
        assert(clr_desc_tostring);
        clr_desc_ctor = mono_method_desc_new("::.ctor(AtomList)",FALSE);
        assert(clr_desc_ctor);

        MonoMethodDesc *desc = mono_method_desc_new("System.Reflection.MethodBase:Invoke(object,object[])",FALSE);
        clr_meth_invoke = mono_method_desc_search_in_image(desc,mono_get_corlib());

        MonoClass *delegate = mono_class_from_name(mono_get_corlib(),"System","Delegate");
        assert(delegate);
        clr_prop_method = mono_class_get_property_from_name(delegate,"Method");
        assert(clr_prop_method);

        // static objects to avoid allocation at method call time
        clr_objarr_1 = mono_array_new(monodomain,mono_get_object_class(),1);
        clr_objarr_2 = mono_array_new(monodomain,mono_get_object_class(),2);
        clr_obj_single = mono_object_new(monodomain,mono_get_single_class());
        clr_obj_symbol = mono_object_new(monodomain,clr_symbol);
        clr_obj_pointer = mono_object_new(monodomain,clr_pointer);
        clr_obj_atomlist = mono_object_new(monodomain,clr_atomlist);
        // unboxed addresses
        clr_val_single = (float *)mono_object_unbox(clr_obj_single);
        clr_val_symbol = (t_symbol **)mono_object_unbox(clr_obj_symbol);
        clr_val_pointer = (void **)mono_object_unbox(clr_obj_pointer);
        clr_val_atomlist = (AtomList *)mono_object_unbox(clr_obj_atomlist);

        // install loader hook
        sys_loader(classloader);

        // ready!
	    post("CLR extension - (c)2006 Davide Morelli, Thomas Grill");
    }
    else
        error("clr: mono domain couldn't be initialized!");
}