/* Copyright (c) 2021 Xie Meiyi(xiemeiyi@hust.edu.cn) and OceanBase and/or its affiliates. All rights reserved.
miniob is licensed under Mulan PSL v2.
You can use this software according to the terms and conditions of the Mulan PSL v2.
You may obtain a copy of Mulan PSL v2 at:
         http://license.coscl.org.cn/MulanPSL2
THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
See the Mulan PSL v2 for more details. */

//
// Created by Meiyi 
//

#include <mutex>
#include "sql/parser/parse.h"
#include "rc.h"
#include "common/log/log.h"

RC parse(char *st, Query *sqln);

void relation_attr_init(RelAttr *relation_attr, char *relation_name, char *attribute_name)
{
  if (relation_name != nullptr) {
    relation_attr->relation_name = relation_name;
  } else {
    relation_attr->relation_name = nullptr;
  }
  relation_attr->attribute_name = attribute_name;
}

void relation_attr_destroy(RelAttr *relation_attr)
{
  free(relation_attr->relation_name);
  free(relation_attr->attribute_name);
  relation_attr->relation_name = nullptr;
  relation_attr->attribute_name = nullptr;
}

void value_init_integer(Value *value, int v)
{
  value->type = INTS;
  value->data = malloc(sizeof(v));
  memcpy(value->data, &v, sizeof(v));
}
void value_init_float(Value *value, float v)
{
  value->type = FLOATS;
  value->data = malloc(sizeof(v));
  memcpy(value->data, &v, sizeof(v));
}
void value_init_string(Value *value, char *v)
{
  value->type = CHARS;
  value->data = v;
}
void value_init_string(Value *value, const char *v)
{
  value->type = CHARS;
  value->data = strdup(v);
}
void value_destroy(Value *value)
{
  value->type = UNDEFINED;
  free(value->data);
  value->data = nullptr;
}

void condition_init(Condition *condition, CompOp comp, int left_is_attr, RelAttr *left_attr, Value *left_value,
    int right_is_attr, RelAttr *right_attr, Value *right_value)
{
  condition->comp = comp;
  condition->left_is_attr = left_is_attr;
  if (left_is_attr) {
    condition->left_attr = *left_attr;
  } else {
    condition->left_value = *left_value;
  }

  condition->right_is_attr = right_is_attr;
  if (right_is_attr) {
    condition->right_attr = *right_attr;
  } else {
    condition->right_value = *right_value;
  }
}
void condition_destroy(Condition *condition)
{
  if (condition->left_is_attr) {
    relation_attr_destroy(&condition->left_attr);
  } else {
    value_destroy(&condition->left_value);
  }
  if (condition->right_is_attr) {
    relation_attr_destroy(&condition->right_attr);
  } else {
    value_destroy(&condition->right_value);
  }
}

void attr_info_init(AttrInfo *attr_info, char *name, AttrType type, size_t length)
{
  attr_info->name = name;
  attr_info->type = type;
  attr_info->length = length;
}
void attr_info_destroy(AttrInfo *attr_info)
{
  free(attr_info->name);
  attr_info->name = nullptr;
}

void selects_init(Selects *selects, ...);
void selects_append_attribute(Selects *selects, RelAttr *rel_attr)
{
  selects->attributes[selects->attr_num++] = *rel_attr;
}
void selects_append_relation(Selects *selects, char *relation_name)
{
  selects->relations[selects->relation_num++] = relation_name;
}

void selects_append_conditions(Selects *selects, Condition conditions[], size_t condition_num)
{
  assert(condition_num <= sizeof(selects->conditions) / sizeof(selects->conditions[0]));
  for (size_t i = 0; i < condition_num; i++) {
    selects->conditions[i] = conditions[i];
  }
  selects->condition_num = condition_num;
}

void selects_destroy(Selects *selects)
{
  for (size_t i = 0; i < selects->attr_num; i++) {
    relation_attr_destroy(&selects->attributes[i]);
  }
  selects->attr_num = 0;

  for (size_t i = 0; i < selects->relation_num; i++) {
    free(selects->relations[i]);
    selects->relations[i] = NULL;
  }
  selects->relation_num = 0;

  for (size_t i = 0; i < selects->condition_num; i++) {
    condition_destroy(&selects->conditions[i]);
  }
  selects->condition_num = 0;
}

void inserts_init(Inserts *inserts, char *relation_name, Value values[], size_t value_num)
{
  assert(value_num <= sizeof(inserts->values) / sizeof(inserts->values[0]));

  inserts->relation_name = relation_name;
  for (size_t i = 0; i < value_num; i++) {
    inserts->values[i] = values[i];
  }
  inserts->value_num = value_num;
}
void inserts_destroy(Inserts *inserts)
{
  free(inserts->relation_name);
  inserts->relation_name = nullptr;

  for (size_t i = 0; i < inserts->value_num; i++) {
    value_destroy(&inserts->values[i]);
  }
  inserts->value_num = 0;
}

void deletes_init_relation(Deletes *deletes, char *relation_name)
{
  deletes->relation_name = relation_name;
}

void deletes_set_conditions(Deletes *deletes, Condition conditions[], size_t condition_num)
{
  assert(condition_num <= sizeof(deletes->conditions) / sizeof(deletes->conditions[0]));
  for (size_t i = 0; i < condition_num; i++) {
    deletes->conditions[i] = conditions[i];
  }
  deletes->condition_num = condition_num;
}
void deletes_destroy(Deletes *deletes)
{
  for (size_t i = 0; i < deletes->condition_num; i++) {
    condition_destroy(&deletes->conditions[i]);
  }
  deletes->condition_num = 0;
  free(deletes->relation_name);
  deletes->relation_name = nullptr;
}

void updates_init(Updates *updates, char *relation_name, char *attribute_name, Value *value,
    Condition conditions[], size_t condition_num)
{
  updates->relation_name = relation_name;
  updates->attribute_name = attribute_name;
  updates->value = *value;

  assert(condition_num <= sizeof(updates->conditions) / sizeof(updates->conditions[0]));
  for (size_t i = 0; i < condition_num; i++) {
    updates->conditions[i] = conditions[i];
  }
  updates->condition_num = condition_num;
}

void updates_destroy(Updates *updates)
{
  free(updates->relation_name);
  free(updates->attribute_name);
  updates->relation_name = nullptr;
  updates->attribute_name = nullptr;

  value_destroy(&updates->value);

  for (size_t i = 0; i < updates->condition_num; i++) {
    condition_destroy(&updates->conditions[i]);
  }
  updates->condition_num = 0;
}

void create_table_append_attribute(CreateTable *create_table, AttrInfo *attr_info)
{
  create_table->attributes[create_table->attribute_count++] = *attr_info;
}

void create_table_init_name(CreateTable *create_table, char *relation_name)
{
  create_table->relation_name = relation_name;
}

void create_table_destroy(CreateTable *create_table)
{
  for (size_t i = 0; i < create_table->attribute_count; i++) {
    attr_info_destroy(&create_table->attributes[i]);
  }
  create_table->attribute_count = 0;
  free(create_table->relation_name);
  create_table->relation_name = nullptr;
}

void drop_table_init(DropTable *drop_table, char *relation_name)
{
  drop_table->relation_name = relation_name;
}

void drop_table_destroy(DropTable *drop_table)
{
  free(drop_table->relation_name);
  drop_table->relation_name = nullptr;
}

void create_index_init(
    CreateIndex *create_index, char *index_name, char *relation_name, char *attr_name)
{
  create_index->index_name = index_name;
  create_index->relation_name = relation_name;
  create_index->attribute_name = attr_name;
}

void create_index_destroy(CreateIndex *create_index)
{
  free(create_index->index_name);
  free(create_index->relation_name);
  free(create_index->attribute_name);

  create_index->index_name = nullptr;
  create_index->relation_name = nullptr;
  create_index->attribute_name = nullptr;
}

void drop_index_init(DropIndex *drop_index, char *index_name)
{
  drop_index->index_name = index_name;
}

void drop_index_destroy(DropIndex *drop_index)
{
  free((char *)drop_index->index_name);
  drop_index->index_name = nullptr;
}

void desc_table_init(DescTable *desc_table, char *relation_name)
{
  desc_table->relation_name = relation_name;
}

void desc_table_destroy(DescTable *desc_table)
{
  free((char *)desc_table->relation_name);
  desc_table->relation_name = nullptr;
}

void load_data_init(LoadData *load_data, char *relation_name, char *file_name)
{
  load_data->relation_name = relation_name;

  if (file_name[0] == '\'' || file_name[0] == '\"') {
    file_name++;
  }
  char *dup_file_name = file_name;
  int len = strlen(dup_file_name);
  if (dup_file_name[len - 1] == '\'' || dup_file_name[len - 1] == '\"') {
    dup_file_name[len - 1] = 0;
  }
  load_data->file_name = dup_file_name;
}

void load_data_destroy(LoadData *load_data)
{
  free((char *)load_data->relation_name);
  free((char *)load_data->file_name);
  load_data->relation_name = nullptr;
  load_data->file_name = nullptr;
}

void query_init(Query *query)
{
  query->flag = SCF_ERROR;
  memset(&query->sstr, 0, sizeof(query->sstr));
}

Query *query_create()
{
  Query *query = (Query *)malloc(sizeof(Query));
  if (nullptr == query) {
    LOG_ERROR("Failed to alloc memroy for query. size=%ld", sizeof(Query));
    return nullptr;
  }

  query_init(query);
  return query;
}

void query_reset(Query *query)
{
  switch (query->flag) {
    case SCF_SELECT: {
      selects_destroy(&query->sstr.selection);
    } break;
    case SCF_INSERT: {
      inserts_destroy(&query->sstr.insertion);
    } break;
    case SCF_DELETE: {
      deletes_destroy(&query->sstr.deletion);
    } break;
    case SCF_UPDATE: {
      updates_destroy(&query->sstr.update);
    } break;
    case SCF_CREATE_TABLE: {
      create_table_destroy(&query->sstr.create_table);
    } break;
    case SCF_DROP_TABLE: {
      drop_table_destroy(&query->sstr.drop_table);
    } break;
    case SCF_CREATE_INDEX: {
      create_index_destroy(&query->sstr.create_index);
    } break;
    case SCF_DROP_INDEX: {
      drop_index_destroy(&query->sstr.drop_index);
    } break;
    case SCF_SYNC: {

    } break;
    case SCF_SHOW_TABLES:
      break;

    case SCF_DESC_TABLE: {
      desc_table_destroy(&query->sstr.desc_table);
    } break;

    case SCF_LOAD_DATA: {
      load_data_destroy(&query->sstr.load_data);
    } break;
    case SCF_CLOG_SYNC:
    case SCF_BEGIN:
    case SCF_COMMIT:
    case SCF_ROLLBACK:
    case SCF_HELP:
    case SCF_EXIT:
    case SCF_ERROR:
      break;
  }
}

void query_destroy(Query *query)
{
  query_reset(query);
  free(query);
}

const char *ATTR_TYPE_NAME[] = {"undefined", "chars", "ints", "floats"};

const char *attr_type_to_string(AttrType type)
{
  if (type >= UNDEFINED && type <= FLOATS) {
    return ATTR_TYPE_NAME[type];
  }
  return "unknown";
}
AttrType attr_type_from_string(const char *s)
{
  for (unsigned int i = 0; i < sizeof(ATTR_TYPE_NAME) / sizeof(ATTR_TYPE_NAME[0]); i++) {
    if (0 == strcmp(ATTR_TYPE_NAME[i], s)) {
      return (AttrType)i;
    }
  }
  return UNDEFINED;
}

////////////////////////////////////////////////////////////////////////////////

int sql_parse(const char *st, Query *sqls);

RC parse(const char *st, Query *sqln)
{
  sql_parse(st, sqln);

  if (sqln->flag == SCF_ERROR)
    return SQL_SYNTAX;
  else
    return SUCCESS;
}