/*
 * MessagePack unpacking routine template
 *
 * Copyright (C) 2008-2010 FURUHASHI Sadayuki
 *
 *    Licensed under the Apache License, Version 2.0 (the "License");
 *    you may not use this file except in compliance with the License.
 *    You may obtain a copy of the License at
 *
 *        http://www.apache.org/licenses/LICENSE-2.0
 *
 *    Unless required by applicable law or agreed to in writing, software
 *    distributed under the License is distributed on an "AS IS" BASIS,
 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *    See the License for the specific language governing permissions and
 *    limitations under the License.
 */

#ifndef msgpack_unpack_func
#error msgpack_unpack_func template is not defined
#endif

#ifndef msgpack_unpack_callback
#error msgpack_unpack_callback template is not defined
#endif

#ifndef msgpack_unpack_struct
#error msgpack_unpack_struct template is not defined
#endif

#ifndef msgpack_unpack_struct_decl
#define msgpack_unpack_struct_decl(name) msgpack_unpack_struct(name)
#endif

#ifndef msgpack_unpack_object
#error msgpack_unpack_object type is not defined
#endif

#ifndef msgpack_unpack_user
#error msgpack_unpack_user type is not defined
#endif

#ifndef USE_CASE_RANGE
#if !defined(_MSC_VER)
#define USE_CASE_RANGE
#endif
#endif

msgpack_unpack_struct_decl(_stack) {
    msgpack_unpack_object obj;
    size_t count;
    unsigned int ct;
    msgpack_unpack_object map_key;
};

msgpack_unpack_struct_decl(_context) {
    msgpack_unpack_user user;
    unsigned int cs;
    unsigned int trail;
    unsigned int top;
    /*
    msgpack_unpack_struct(_stack)* stack;
    unsigned int stack_size;
    msgpack_unpack_struct(_stack) embed_stack[MSGPACK_EMBED_STACK_SIZE];
    */
    msgpack_unpack_struct(_stack) stack[MSGPACK_EMBED_STACK_SIZE];
};


msgpack_unpack_func(void, _init)(msgpack_unpack_struct(_context)* ctx)
{
    ctx->cs = MSGPACK_CS_HEADER;
    ctx->trail = 0;
    ctx->top = 0;
    /*
    ctx->stack = ctx->embed_stack;
    ctx->stack_size = MSGPACK_EMBED_STACK_SIZE;
    */
    ctx->stack[0].obj = msgpack_unpack_callback(_root)(&ctx->user);
}

/*
msgpack_unpack_func(void, _destroy)(msgpack_unpack_struct(_context)* ctx)
{
    if(ctx->stack_size != MSGPACK_EMBED_STACK_SIZE) {
        free(ctx->stack);
    }
}
*/

msgpack_unpack_func(msgpack_unpack_object, _data)(msgpack_unpack_struct(_context)* ctx)
{
    return (ctx)->stack[0].obj;
}


msgpack_unpack_func(int, _execute)(msgpack_unpack_struct(_context)* ctx, const char* data, size_t len, size_t* off)
{
    assert(len >= *off);

    const unsigned char* p = (unsigned char*)data + *off;
    const unsigned char* const pe = (unsigned char*)data + len;
    const void* n = NULL;

    unsigned int trail = ctx->trail;
    unsigned int cs = ctx->cs;
    unsigned int top = ctx->top;
    msgpack_unpack_struct(_stack)* stack = ctx->stack;
    /*
    unsigned int stack_size = ctx->stack_size;
    */
    msgpack_unpack_user* user = &ctx->user;

    msgpack_unpack_object obj;
    msgpack_unpack_struct(_stack)* c = NULL;

    int ret;

#define push_simple_value(func) \
    if(msgpack_unpack_callback(func)(user, &obj) < 0) { goto _failed; } \
    goto _push
#define push_fixed_value(func, arg) \
    if(msgpack_unpack_callback(func)(user, arg, &obj) < 0) { goto _failed; } \
    goto _push
#define push_variable_value(func, base, pos, len) \
    if(msgpack_unpack_callback(func)(user, \
        (const char*)base, (const char*)pos, len, &obj) < 0) { goto _failed; } \
    goto _push

#define again_fixed_trail(_cs, trail_len) \
    trail = trail_len; \
    cs = _cs; \
    goto _fixed_trail_again
#define again_fixed_trail_if_zero(_cs, trail_len, ifzero) \
    trail = trail_len; \
    if(trail == 0) { goto ifzero; } \
    cs = _cs; \
    goto _fixed_trail_again

#define start_container(func, count_, ct_) \
    if(top >= MSGPACK_EMBED_STACK_SIZE) { goto _failed; } /* FIXME */ \
    if(msgpack_unpack_callback(func)(user, count_, &stack[top].obj) < 0) { goto _failed; } \
    if((count_) == 0) { obj = stack[top].obj; goto _push; } \
    stack[top].ct = ct_; \
    stack[top].count = count_; \
    ++top; \
    /*printf("container %d count %d stack %d\n",stack[top].obj,count_,top);*/ \
    /*printf("stack push %d\n", top);*/ \
    /* FIXME \
    if(top >= stack_size) { \
        if(stack_size == MSGPACK_EMBED_STACK_SIZE) { \
            size_t csize = sizeof(msgpack_unpack_struct(_stack)) * MSGPACK_EMBED_STACK_SIZE; \
            size_t nsize = csize * 2; \
            msgpack_unpack_struct(_stack)* tmp = (msgpack_unpack_struct(_stack)*)malloc(nsize); \
            if(tmp == NULL) { goto _failed; } \
            memcpy(tmp, ctx->stack, csize); \
            ctx->stack = stack = tmp; \
            ctx->stack_size = stack_size = MSGPACK_EMBED_STACK_SIZE * 2; \
        } else { \
            size_t nsize = sizeof(msgpack_unpack_struct(_stack)) * ctx->stack_size * 2; \
            msgpack_unpack_struct(_stack)* tmp = (msgpack_unpack_struct(_stack)*)realloc(ctx->stack, nsize); \
            if(tmp == NULL) { goto _failed; } \
            ctx->stack = stack = tmp; \
            ctx->stack_size = stack_size = stack_size * 2; \
        } \
    } \
    */ \
    goto _header_again

#define NEXT_CS(p) \
    ((unsigned int)*p & 0x1f)

#ifdef USE_CASE_RANGE
#define SWITCH_RANGE_BEGIN     switch(*p) {
#define SWITCH_RANGE(FROM, TO) case FROM ... TO:
#define SWITCH_RANGE_DEFAULT   default:
#define SWITCH_RANGE_END       }
#else
#define SWITCH_RANGE_BEGIN     { if(0) {
#define SWITCH_RANGE(FROM, TO) } else if(FROM <= *p && *p <= TO) {
#define SWITCH_RANGE_DEFAULT   } else {
#define SWITCH_RANGE_END       } }
#endif

    if(p == pe) { goto _out; }
    do {
        switch(cs) {
        case MSGPACK_CS_HEADER:
            SWITCH_RANGE_BEGIN
            SWITCH_RANGE(0x00, 0x7f)  // Positive Fixnum
                push_fixed_value(_uint8, *(uint8_t*)p);
            SWITCH_RANGE(0xe0, 0xff)  // Negative Fixnum
                push_fixed_value(_int8, *(int8_t*)p);
            SWITCH_RANGE(0xc0, 0xdf)  // Variable
                switch(*p) {
                case 0xc0:  // nil
                    push_simple_value(_nil);
                //case 0xc1:  // string
                //  again_terminal_trail(NEXT_CS(p), p+1);
                case 0xc2:  // false
                    push_simple_value(_false);
                case 0xc3:  // true
                    push_simple_value(_true);
                case 0xc4: // bin 8
                case 0xc5: // bin 16
                case 0xc6: // bin 32
                    again_fixed_trail(NEXT_CS(p), 1 << (((unsigned int)*p) & 0x03));
                case 0xc7: // ext 8
                case 0xc8: // ext 16
                case 0xc9: // ext 32
                    again_fixed_trail(NEXT_CS(p), 1 << ((((unsigned int)*p) + 1) & 0x03));
                case 0xca:  // float
                case 0xcb:  // double
                case 0xcc:  // unsigned int  8
                case 0xcd:  // unsigned int 16
                case 0xce:  // unsigned int 32
                case 0xcf:  // unsigned int 64
                case 0xd0:  // signed int  8
                case 0xd1:  // signed int 16
                case 0xd2:  // signed int 32
                case 0xd3:  // signed int 64
                    again_fixed_trail(NEXT_CS(p), 1 << (((unsigned int)*p) & 0x03));
                case 0xd4:  // fixext 1
                case 0xd5:  // fixext 2
                case 0xd6:  // fixext 4
                case 0xd7:  // fixext 8
                    again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE,
                        (1 << (((unsigned int)*p) & 0x03)) + 1, _ext_zero);
                case 0xd8:  // fixext 16
                    again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, 16+1, _ext_zero);

                case 0xd9:  // str 8
                case 0xda:  // str 16
                case 0xdb:  // str 32
                    again_fixed_trail(NEXT_CS(p), 1 << ((((unsigned int)*p) & 0x03) - 1));
                case 0xdc:  // array 16
                case 0xdd:  // array 32
                case 0xde:  // map 16
                case 0xdf:  // map 32
                    again_fixed_trail(NEXT_CS(p), 2u << (((unsigned int)*p) & 0x01));
                default:
                    goto _failed;
                }
            SWITCH_RANGE(0xa0, 0xbf)  // FixStr
                again_fixed_trail_if_zero(MSGPACK_ACS_STR_VALUE, ((unsigned int)*p & 0x1f), _str_zero);
            SWITCH_RANGE(0x90, 0x9f)  // FixArray
                start_container(_array, ((unsigned int)*p) & 0x0f, MSGPACK_CT_ARRAY_ITEM);
            SWITCH_RANGE(0x80, 0x8f)  // FixMap
                start_container(_map, ((unsigned int)*p) & 0x0f, MSGPACK_CT_MAP_KEY);

            SWITCH_RANGE_DEFAULT
                goto _failed;
            SWITCH_RANGE_END
            // end MSGPACK_CS_HEADER


        _fixed_trail_again:
            ++p;

        default:
            if((size_t)(pe - p) < trail) { goto _out; }
            n = p;  p += trail - 1;
            switch(cs) {
            //case MSGPACK_CS_
            //case MSGPACK_CS_
            case MSGPACK_CS_FLOAT: {
                    union { uint32_t i; float f; } mem;
                    _msgpack_load32(uint32_t, n, &mem.i);
                    push_fixed_value(_float, mem.f); }
            case MSGPACK_CS_DOUBLE: {
                    union { uint64_t i; double f; } mem;
                    _msgpack_load64(uint64_t, n, &mem.i);
#if defined(__arm__) && !(__ARM_EABI__) // arm-oabi
                    // https://github.com/msgpack/msgpack-perl/pull/1
                    mem.i = (mem.i & 0xFFFFFFFFUL) << 32UL | (mem.i >> 32UL);
#endif
                    push_fixed_value(_double, mem.f); }
            case MSGPACK_CS_UINT_8:
                push_fixed_value(_uint8, *(uint8_t*)n);
            case MSGPACK_CS_UINT_16:{
                uint16_t tmp;
                _msgpack_load16(uint16_t,n,&tmp);
                push_fixed_value(_uint16, tmp);
            }
            case MSGPACK_CS_UINT_32:{
                uint32_t tmp;
                _msgpack_load32(uint32_t,n,&tmp);
                push_fixed_value(_uint32, tmp);
            }
            case MSGPACK_CS_UINT_64:{
                uint64_t tmp;
                _msgpack_load64(uint64_t,n,&tmp);
                push_fixed_value(_uint64, tmp);
            }
            case MSGPACK_CS_INT_8:
                push_fixed_value(_int8, *(int8_t*)n);
            case MSGPACK_CS_INT_16:{
                int16_t tmp;
                _msgpack_load16(int16_t,n,&tmp);
                push_fixed_value(_int16, tmp);
            }
            case MSGPACK_CS_INT_32:{
                int32_t tmp;
                _msgpack_load32(int32_t,n,&tmp);
                push_fixed_value(_int32, tmp);
            }
            case MSGPACK_CS_INT_64:{
                int64_t tmp;
                _msgpack_load64(int64_t,n,&tmp);
                push_fixed_value(_int64, tmp);
            }
            case MSGPACK_CS_FIXEXT_1:
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, 1+1, _ext_zero);
            case MSGPACK_CS_FIXEXT_2:
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, 2+1, _ext_zero);
            case MSGPACK_CS_FIXEXT_4:
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, 4+1, _ext_zero);
            case MSGPACK_CS_FIXEXT_8:
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, 8+1, _ext_zero);
            case MSGPACK_CS_FIXEXT_16:
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, 16+1, _ext_zero);
            case MSGPACK_CS_STR_8:
                again_fixed_trail_if_zero(MSGPACK_ACS_STR_VALUE, *(uint8_t*)n, _str_zero);
            case MSGPACK_CS_BIN_8:
                again_fixed_trail_if_zero(MSGPACK_ACS_BIN_VALUE, *(uint8_t*)n, _bin_zero);
            case MSGPACK_CS_EXT_8:
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, (*(uint8_t*)n) + 1, _ext_zero);
            case MSGPACK_CS_STR_16:{
                uint16_t tmp;
                _msgpack_load16(uint16_t,n,&tmp);
                again_fixed_trail_if_zero(MSGPACK_ACS_STR_VALUE, tmp, _str_zero);
            }
            case MSGPACK_CS_BIN_16:{
                uint16_t tmp;
                _msgpack_load16(uint16_t,n,&tmp);
                again_fixed_trail_if_zero(MSGPACK_ACS_BIN_VALUE, tmp, _bin_zero);
            }
            case MSGPACK_CS_EXT_16:{
                uint16_t tmp;
                _msgpack_load16(uint16_t,n,&tmp);
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, tmp + 1, _ext_zero);
            }
            case MSGPACK_CS_STR_32:{
                uint32_t tmp;
                _msgpack_load32(uint32_t,n,&tmp);
                again_fixed_trail_if_zero(MSGPACK_ACS_STR_VALUE, tmp, _str_zero);
            }
            case MSGPACK_CS_BIN_32:{
                uint32_t tmp;
                _msgpack_load32(uint32_t,n,&tmp);
                again_fixed_trail_if_zero(MSGPACK_ACS_BIN_VALUE, tmp, _bin_zero);
            }
            case MSGPACK_CS_EXT_32:{
                uint32_t tmp;
                _msgpack_load32(uint32_t,n,&tmp);
                again_fixed_trail_if_zero(MSGPACK_ACS_EXT_VALUE, tmp + 1, _ext_zero);
            }
            case MSGPACK_ACS_STR_VALUE:
            _str_zero:
                push_variable_value(_str, data, n, trail);
            case MSGPACK_ACS_BIN_VALUE:
            _bin_zero:
                push_variable_value(_bin, data, n, trail);
            case MSGPACK_ACS_EXT_VALUE:
            _ext_zero:
                push_variable_value(_ext, data, n, trail);

            case MSGPACK_CS_ARRAY_16:{
                uint16_t tmp;
                _msgpack_load16(uint16_t,n,&tmp);
                start_container(_array, tmp, MSGPACK_CT_ARRAY_ITEM);
            }
            case MSGPACK_CS_ARRAY_32:{
                /* FIXME security guard */
                uint32_t tmp;
                _msgpack_load32(uint32_t,n,&tmp);
                start_container(_array, tmp, MSGPACK_CT_ARRAY_ITEM);
            }

            case MSGPACK_CS_MAP_16:{
                uint16_t tmp;
                _msgpack_load16(uint16_t,n,&tmp);
                start_container(_map, tmp, MSGPACK_CT_MAP_KEY);
            }
            case MSGPACK_CS_MAP_32:{
                /* FIXME security guard */
                uint32_t tmp;
                _msgpack_load32(uint32_t,n,&tmp);
                start_container(_map, tmp, MSGPACK_CT_MAP_KEY);
            }

            default:
                goto _failed;
            }
        }

_push:
    if(top == 0) { goto _finish; }
    c = &stack[top-1];
    switch(c->ct) {
    case MSGPACK_CT_ARRAY_ITEM:
        if(msgpack_unpack_callback(_array_item)(user, &c->obj, obj) < 0) { goto _failed; }
        if(--c->count == 0) {
            obj = c->obj;
            --top;
            /*printf("stack pop %d\n", top);*/
            goto _push;
        }
        goto _header_again;
    case MSGPACK_CT_MAP_KEY:
        c->map_key = obj;
        c->ct = MSGPACK_CT_MAP_VALUE;
        goto _header_again;
    case MSGPACK_CT_MAP_VALUE:
        if(msgpack_unpack_callback(_map_item)(user, &c->obj, c->map_key, obj) < 0) { goto _failed; }
        if(--c->count == 0) {
            obj = c->obj;
            --top;
            /*printf("stack pop %d\n", top);*/
            goto _push;
        }
        c->ct = MSGPACK_CT_MAP_KEY;
        goto _header_again;

    default:
        goto _failed;
    }

_header_again:
        cs = MSGPACK_CS_HEADER;
        ++p;
    } while(p != pe);
    goto _out;


_finish:
    stack[0].obj = obj;
    ++p;
    ret = 1;
    /*printf("-- finish --\n"); */
    goto _end;

_failed:
    /*printf("** FAILED **\n"); */
    ret = -1;
    goto _end;

_out:
    ret = 0;
    goto _end;

_end:
    ctx->cs = cs;
    ctx->trail = trail;
    ctx->top = top;
    *off = (size_t)(p - (const unsigned char*)data);

    return ret;
}


#undef msgpack_unpack_func
#undef msgpack_unpack_callback
#undef msgpack_unpack_struct
#undef msgpack_unpack_object
#undef msgpack_unpack_user

#undef push_simple_value
#undef push_fixed_value
#undef push_variable_value
#undef again_fixed_trail
#undef again_fixed_trail_if_zero
#undef start_container

#undef NEXT_CS

#undef SWITCH_RANGE_BEGIN
#undef SWITCH_RANGE
#undef SWITCH_RANGE_DEFAULT
#undef SWITCH_RANGE_END