/*
 * This file is part of the MicroPython project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2014-2016 Paul Sokolovsky
 * Copyright (c) Quectel Wireless Solution, Co., Ltd.All Rights Reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <stdio.h>
#include <string.h>

#include "py/runtime.h"
#include "py/stream.h"
#include "py/mperrno.h"

#if MICROPY_PY_UZLIB

#include "uzlib/tinf.h"

#if 0 // print debugging info
#define DEBUG_printf DEBUG_printf
#else // don't print debugging info
#define DEBUG_printf(...) (void)0
#endif

typedef struct _mp_obj_decompio_t {
 mp_obj_base_t base;
 mp_obj_t src_stream;
 TINF_DATA decomp;
 bool eof;
} mp_obj_decompio_t;

STATIC int read_src_stream(TINF_DATA *data) {
 byte *p = (void *)data;
 p -= offsetof(mp_obj_decompio_t, decomp);
 mp_obj_decompio_t *self = (mp_obj_decompio_t *)p;

 const mp_stream_p_t *stream = mp_get_stream(self->src_stream);
 int err;
 byte c;
 mp_uint_t out_sz = stream->read(self->src_stream, &c, 1, &err);
 if (out_sz == MP_STREAM_ERROR) {
 mp_raise_OSError(err);
 }
 if (out_sz == 0) {
 mp_raise_type(&mp_type_EOFError);
 }
 return c;
}

STATIC mp_obj_t decompio_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
 mp_arg_check_num(n_args, n_kw, 1, 2, false);
 mp_get_stream_raise(args[0], MP_STREAM_OP_READ);
 mp_obj_decompio_t *o = m_new_obj(mp_obj_decompio_t);
 o->base.type = type;
 memset(&o->decomp, 0, sizeof(o->decomp));
 o->decomp.readSource = read_src_stream;
 o->src_stream = args[0];
 o->eof = false;

 mp_int_t dict_opt = 0;
 int dict_sz;
 if (n_args > 1) {
 dict_opt = mp_obj_get_int(args[1]);
 }

 if (dict_opt >= 16) {
 int st = uzlib_gzip_parse_header(&o->decomp);
 if (st != TINF_OK) {
 goto header_error;
 }
 dict_sz = 1 << (dict_opt - 16);
 } else if (dict_opt >= 0) {
 dict_opt = uzlib_zlib_parse_header(&o->decomp);
 if (dict_opt < 0) {
 header_error:
 mp_raise_ValueError(MP_ERROR_TEXT("compression header"));
 }
 dict_sz = 1 << dict_opt;
 } else {
 dict_sz = 1 << -dict_opt;
 }

 uzlib_uncompress_init(&o->decomp, m_new(byte, dict_sz), dict_sz);
 return MP_OBJ_FROM_PTR(o);
}

STATIC mp_uint_t decompio_read(mp_obj_t o_in, void *buf, mp_uint_t size, int *errcode) {
 mp_obj_decompio_t *o = MP_OBJ_TO_PTR(o_in);
 if (o->eof) {
 return 0;
 }

 o->decomp.dest = buf;
 o->decomp.dest_limit = (byte *)buf + size;
 int st = uzlib_uncompress_chksum(&o->decomp);
 if (st == TINF_DONE) {
 o->eof = true;
 }
 if (st < 0) {
 *errcode = MP_EINVAL;
 return MP_STREAM_ERROR;
 }
 return o->decomp.dest - (byte *)buf;
}

#if !MICROPY_ENABLE_DYNRUNTIME
STATIC const mp_rom_map_elem_t decompio_locals_dict_table[] = {
 { MP_ROM_QSTR(MP_QSTR_read), MP_ROM_PTR(&mp_stream_read_obj) },
 { MP_ROM_QSTR(MP_QSTR_readinto), MP_ROM_PTR(&mp_stream_readinto_obj) },
 { MP_ROM_QSTR(MP_QSTR_readline), MP_ROM_PTR(&mp_stream_unbuffered_readline_obj) },
};

STATIC MP_DEFINE_CONST_DICT(decompio_locals_dict, decompio_locals_dict_table);
#endif

STATIC const mp_stream_p_t decompio_stream_p = {
 .read = decompio_read,
};

#if !MICROPY_ENABLE_DYNRUNTIME
STATIC const mp_obj_type_t decompio_type = {
 { &mp_type_type },
 .name = MP_QSTR_DecompIO,
 .make_new = decompio_make_new,
 .protocol = &decompio_stream_p,
 .locals_dict = (void *)&decompio_locals_dict,
};
#endif

STATIC mp_obj_t mod_uzlib_decompress(size_t n_args, const mp_obj_t *args) {
 mp_obj_t data = args[0];
 mp_buffer_info_t bufinfo;
 mp_get_buffer_raise(data, &bufinfo, MP_BUFFER_READ);

 TINF_DATA *decomp = m_new_obj(TINF_DATA);
 memset(decomp, 0, sizeof(*decomp));
 DEBUG_printf("sizeof(TINF_DATA)=" UINT_FMT "\n", sizeof(*decomp));
 uzlib_uncompress_init(decomp, NULL, 0);
 mp_uint_t dest_buf_size = (bufinfo.len + 15) & ~15;
 byte *dest_buf = m_new(byte, dest_buf_size);

 decomp->dest = dest_buf;
 decomp->dest_limit = dest_buf + dest_buf_size;
 DEBUG_printf("uzlib: Initial out buffer: " UINT_FMT " bytes\n", dest_buf_size);
 decomp->source = bufinfo.buf;
 decomp->source_limit = (byte *)bufinfo.buf + bufinfo.len;

 int st;
 bool is_zlib = true;

 if (n_args > 1 && MP_OBJ_SMALL_INT_VALUE(args[1]) < 0) {
 is_zlib = false;
 }

 if (is_zlib) {
 st = uzlib_zlib_parse_header(decomp);
 if (st < 0) {
 goto error;
 }
 }

 while (1) {
 st = uzlib_uncompress_chksum(decomp);
 if (st < 0) {
 goto error;
 }
 if (st == TINF_DONE) {
 break;
 }
 size_t offset = decomp->dest - dest_buf;
 dest_buf = m_renew(byte, dest_buf, dest_buf_size, dest_buf_size + 256);
 dest_buf_size += 256;
 decomp->dest = dest_buf + offset;
 decomp->dest_limit = decomp->dest + 256;
 }

 mp_uint_t final_sz = decomp->dest - dest_buf;
 DEBUG_printf("uzlib: Resizing from " UINT_FMT " to final size: " UINT_FMT " bytes\n", dest_buf_size, final_sz);
 dest_buf = (byte *)m_renew(byte, dest_buf, dest_buf_size, final_sz);
 mp_obj_t res = mp_obj_new_bytearray_by_ref(final_sz, dest_buf);
 m_del_obj(TINF_DATA, decomp);
 return res;

error:
 nlr_raise(mp_obj_new_exception_arg1(&mp_type_ValueError, MP_OBJ_NEW_SMALL_INT(st)));
}
STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(mod_uzlib_decompress_obj, 1, 3, mod_uzlib_decompress);

#if !MICROPY_ENABLE_DYNRUNTIME
STATIC const mp_rom_map_elem_t mp_module_uzlib_globals_table[] = {
 { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_uzlib) },
 { MP_ROM_QSTR(MP_QSTR_decompress), MP_ROM_PTR(&mod_uzlib_decompress_obj) },
 { MP_ROM_QSTR(MP_QSTR_DecompIO), MP_ROM_PTR(&decompio_type) },
};

STATIC MP_DEFINE_CONST_DICT(mp_module_uzlib_globals, mp_module_uzlib_globals_table);

const mp_obj_module_t mp_module_uzlib = {
 .base = { &mp_type_module },
 .globals = (mp_obj_dict_t *)&mp_module_uzlib_globals,
};
#endif

// Source files #include'd here to make sure they're compiled in
// only if module is enabled by config setting.

#include "uzlib/tinflate.c"
#include "uzlib/tinfzlib.c"
#include "uzlib/tinfgzip.c"
#include "uzlib/adler32.c"
#include "uzlib/crc32.c"

#endif // MICROPY_PY_UZLIB