/*******************************************************************************
*   Ledger Ethereum App
*   (c) 2016-2019 Ledger
*
*  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.
********************************************************************************/

#include <stdint.h>
#include <string.h>

#include "ethUstream.h"
#include "ethUtils.h"
#include "uint256.h"
#include "tokens.h"

static const unsigned char hex_digits[] = {'0', '1', '2', '3', '4', '5', '6', '7',
                                           '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};

void array_hexstr(char *strbuf, const void *bin, unsigned int len) {
    while (len--) {
        *strbuf++ = hex_digits[((*((char *)bin)) >> 4) & 0xF];
        *strbuf++ = hex_digits[(*((char *)bin)) & 0xF];
        bin = (const void *)((unsigned int)bin + 1);
    }
    *strbuf = 0; // EOS
}

void convertUint256BE(uint8_t *data, uint32_t length, uint256_t *target) {
    uint8_t tmp[32];
    os_memset(tmp, 0, 32);
    os_memmove(tmp + 32 - length, data, length);
    readu256BE(tmp, target);
}

int local_strchr(char *string, char ch) {
    unsigned int length = strlen(string);
    unsigned int i;
    for (i=0; i<length; i++) {
        if (string[i] == ch) {
            return i;
        }
    }
    return -1;
}

uint32_t getV(txContent_t *txContent) {
    uint32_t v = 0;
    if (txContent->vLength == 1) {
      v = txContent->v[0];
    }
    else
    if (txContent->vLength == 2) {
      v = (txContent->v[0] << 8) | txContent->v[1];
    }
    else
    if (txContent->vLength == 3) {
      v = (txContent->v[0] << 16) | (txContent->v[1] << 8) | txContent->v[2];
    }
    else
    if (txContent->vLength == 4) {
      v = (txContent->v[0] << 24) | (txContent->v[1] << 16) |
          (txContent->v[2] << 8) | txContent->v[3];
    }
    else
    if (txContent->vLength != 0) {
        PRINTF("Unexpected v format\n");
        THROW(EXCEPTION);
    }
    return v;
}

void amountToString(uint8_t* amount, uint8_t amount_size, uint8_t decimals, char* ticker, char* out_buffer, uint8_t out_buffer_size){
    uint256_t amount_256;
    char tmp_buffer[100];
    convertUint256BE(amount, amount_size, &amount_256);
    tostring256(&amount_256, 10, tmp_buffer, 100);

    uint8_t amount_len = strnlen(tmp_buffer, sizeof(tmp_buffer));
    uint8_t ticker_len = strnlen(ticker, MAX_TICKER_LEN);

    memcpy(out_buffer, ticker, MIN(out_buffer_size, ticker_len));

    adjustDecimals(tmp_buffer, amount_len, out_buffer + ticker_len, out_buffer_size - ticker_len -1, decimals);
    out_buffer[out_buffer_size-1] = '\0';
}

bool parse_swap_config(uint8_t* config, uint8_t config_len, char* ticker, uint8_t* decimals){
    uint8_t ticker_len, offset = 0;
    if (config_len == 0){
        return false;
    }
    ticker_len = config[offset++];
    if(ticker_len == 0 || ticker_len > MAX_TICKER_LEN - 2 || config_len - offset < ticker_len){
        return false;
    }
    memcpy(ticker, config+offset, ticker_len);
    offset += ticker_len;
    ticker[ticker_len] = ' ';
    ticker[ticker_len+1] = '\0';

    if(config_len - offset < 1){
        return false;
    }
    *decimals = config[offset];
    return true;
}