/*
 * Copyright (c) Hisilicon Technologies Co., Ltd. 2020-2021. All rights reserved.
 * Description: This file is for interpreting the configuration file.
 * Author: Hisilicon
 * Create: 2020-06-11
 */

#include "parse_config_file.h"

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

#include "td_type.h"
#include "securec.h"

#define COMMENT_CHARACTER '#'
#define LINE_SIZE 768
#define LINE_BUF_SIZE (LINE_SIZE + 2)
#define KEY_MAX_LEN  (188 * 10)

static td_char g_avariables[MAX_VAR_NUM][MAX_VAR_NAME_LEN + 1];
static td_char g_avalues[MAX_VAR_NUM][MAX_VAR_VALUE_LEN + 1];
static td_u32 g_var_num = 0;

static td_void remove_trailing_chars(td_char *path, td_char c)
{
    size_t len;

    len = strlen(path);

    while (len > 0 && path[len - 1] == c) {
        path[--len] = '\0';
    }
}

static td_s32 _get_key(td_char **key, td_char **linepos)
{
    td_char *tmppos = TD_NULL;

    if (key == TD_NULL || linepos == TD_NULL) {
        return TD_FAILURE;
    }

    *key = *linepos;
    tmppos = *linepos;

    while (1) {
        tmppos++;

        if (tmppos[0] == '\0') {
            return TD_FAILURE;
        }

        if (isspace(tmppos[0])) {
            break;
        }

        if (tmppos[0] == '=') {
            break;
        }
    }

    /* terminate key */
    tmppos[0] = '\0';

    while (1) {
        tmppos++;

        if (tmppos[0] == '\0') {
            return TD_FAILURE;
        }

        if (isspace(tmppos[0])) {
            continue;
        }

        if (tmppos[0] == '=') {
            continue;
        }
        break;
    }

    *linepos = tmppos;
    return TD_SUCCESS;
}

static td_s32 get_key(td_char **line, td_char **key, td_char **value)
{
    td_s32 ret;
    td_char *linepos = TD_NULL;
    td_char *temp = TD_NULL;

    if (key == TD_NULL || line == TD_NULL || value == TD_NULL) {
        return TD_FAILURE;
    }

    linepos = *line;

    /* skip whitespace */
    while (isspace(linepos[0])) {
        linepos++;
    }

    if (linepos[0] == '\0') {
        return TD_FAILURE;
    }

    ret = _get_key(key, &linepos);
    if (ret != TD_SUCCESS) {
        return ret;
    }

    /* get the value */
    if (linepos[0] == '"') {
        linepos++;
    } else {
        return TD_FAILURE;
    }

    *value = linepos;

    temp = strchr(linepos, '"');
    if (temp == TD_NULL) {
        return TD_FAILURE;
    }

    temp[0] = '\0';
    return TD_SUCCESS;
}

static td_s32 _check_value(const td_char *variable, td_char *value)
{
    if (variable == TD_NULL || value == TD_NULL) {
        return TD_FAILURE;
    }

    if (g_var_num >= MAX_VAR_NUM || strlen(variable) > MAX_VAR_NAME_LEN || strlen(value) > MAX_VAR_VALUE_LEN) {
        printf("error value\n");
        return TD_FAILURE;
    }

    if (strncpy_s(g_avariables[g_var_num], sizeof(g_avariables[g_var_num]),
                  variable, strlen(variable)) != EOK) {
        printf("call strncpy_s error\n");
        return TD_FAILURE;
    }
    remove_trailing_chars(value, '/');
    if (strncpy_s(g_avalues[g_var_num], sizeof(g_avalues[g_var_num]), value, strlen(value)) != EOK) {
        printf("call strncpy_s error\n");
        return TD_FAILURE;
    }

    return TD_SUCCESS;
}

static td_s32 priv_read_file(FILE *cfg_file)
{
    td_char line[LINE_BUF_SIZE];
    td_char *bufline = TD_NULL;
    td_char *linepos = TD_NULL;
    td_char *value = TD_NULL;
    td_char *variable = TD_NULL;
    size_t count;
    td_s32 lineno, retval, ret;

    /* loop through the whole file */
    lineno = 0;
    while (fgets(line, sizeof(line), cfg_file) != NULL) {
        lineno++;
        bufline = line;
        count = strlen(line);
        if (count > LINE_SIZE) {
            continue;
        }

        /* eat the whitespace */
        while ((count > 0) && isspace(bufline[0])) {
            bufline++;
            count--;
        }

        /* see if this is a comment */
        if (bufline[0] == COMMENT_CHARACTER || count == 0) {
            continue;
        }

        if (memmove_s(line, sizeof(line), bufline, count) != EOK) {
            return TD_FAILURE;
        }
        line[count] = '\0';

        linepos = line;

        retval = get_key(&linepos, &variable, &value);
        if (retval != 0) {
            continue;
        }

        ret = _check_value(variable, value);
        if (ret != TD_SUCCESS) {
            continue;
        }

        g_var_num++;
        continue;
    }

    return TD_SUCCESS;
}

td_s32 parse_config_file(const td_char *path_to_config_file, td_s32 *var_num)
{
    td_s32 ret;

    if (var_num == TD_NULL) {
        return TD_FAILURE;
    }

    FILE *cfg_file = fopen(path_to_config_file, "r");
    if (cfg_file == NULL) {
        return TD_FAILURE;
    }

    ret = priv_read_file(cfg_file);

    fclose(cfg_file);
    cfg_file = NULL;

    *var_num = g_var_num;

    return ret;
}

td_char *get_config_var(const td_char *var_name)
{
    td_u32 i;

    if (var_name == TD_NULL) {
        return TD_NULL;
    }

    for (i = 0; i < g_var_num; i++) {
        if (strcasecmp(g_avariables[i], var_name) == 0) {
            return g_avalues[i];
        }
    }

    return TD_NULL;
}

td_s32 get_key_value(const td_char *name, td_u8 *key, td_u32 key_len)
{
    td_char *value = TD_NULL;
    td_s32 i;
    td_char tmp_buf[2]; /* just need 2 bytes as a temporary container */
    td_s32 read;

    if (name == TD_NULL || key == TD_NULL || key_len > KEY_MAX_LEN) {
        return TD_FAILURE;
    }

    value = get_config_var(name);
    if (value == TD_NULL) {
        return TD_FAILURE;
    }

    /* value lenth must less than key_len */
    read = strlen(value) > (key_len * 2) ? key_len : (strlen(value) / 2); /* Equal to key_len or (size of value)/2 */
    for (i = 0; i < read; i++) {
        if (memset_s(tmp_buf, sizeof(tmp_buf), 0, sizeof(tmp_buf)) != EOK) {
            printf("call memcpy_s error\n");
        }
        if (memcpy_s(tmp_buf, sizeof(tmp_buf), value + i * 2, 2) != EOK) { /* copy 2 bytes at a time */
            printf("call memcpy_s error\n");
        }

        key[i] = (td_u8)strtol(tmp_buf, NULL, 16); /* 16 means use hexadecimal */
    }

    return TD_SUCCESS;
}