/*
 * Copyright (C) 2018 The Android Open Source Project
 *
 * 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 SRC_TRACE_PROCESSOR_SQLITE_UTILS_H_
#define SRC_TRACE_PROCESSOR_SQLITE_UTILS_H_

#include <sqlite3.h>

#include <functional>
#include <string>

#include "perfetto/base/logging.h"
#include "src/trace_processor/scoped_db.h"
#include "src/trace_processor/table.h"

namespace perfetto {
namespace trace_processor {
namespace sqlite_utils {

inline bool IsOpEq(int op) {
  return op == SQLITE_INDEX_CONSTRAINT_EQ;
}

inline bool IsOpGe(int op) {
  return op == SQLITE_INDEX_CONSTRAINT_GE;
}

inline bool IsOpGt(int op) {
  return op == SQLITE_INDEX_CONSTRAINT_GT;
}

inline bool IsOpLe(int op) {
  return op == SQLITE_INDEX_CONSTRAINT_LE;
}

inline bool IsOpLt(int op) {
  return op == SQLITE_INDEX_CONSTRAINT_LT;
}

inline std::string OpToString(int op) {
  switch (op) {
    case SQLITE_INDEX_CONSTRAINT_EQ:
      return "=";
    case SQLITE_INDEX_CONSTRAINT_NE:
      return "!=";
    case SQLITE_INDEX_CONSTRAINT_GE:
      return ">=";
    case SQLITE_INDEX_CONSTRAINT_GT:
      return ">";
    case SQLITE_INDEX_CONSTRAINT_LE:
      return "<=";
    case SQLITE_INDEX_CONSTRAINT_LT:
      return "<";
    default:
      PERFETTO_FATAL("Operator to string conversion not impemented for %d", op);
  }
}

template <class T>
std::function<bool(T, T)> GetPredicateForOp(int op) {
  switch (op) {
    case SQLITE_INDEX_CONSTRAINT_EQ:
      return std::equal_to<T>();
    case SQLITE_INDEX_CONSTRAINT_GE:
      return std::greater_equal<T>();
    case SQLITE_INDEX_CONSTRAINT_GT:
      return std::greater<T>();
    case SQLITE_INDEX_CONSTRAINT_LE:
      return std::less_equal<T>();
    case SQLITE_INDEX_CONSTRAINT_LT:
      return std::less<T>();
    case SQLITE_INDEX_CONSTRAINT_NE:
      return std::not_equal_to<T>();
    default:
      PERFETTO_CHECK(false);
  }
}

template <typename T>
T ExtractSqliteValue(sqlite3_value* value);

template <>
inline uint8_t ExtractSqliteValue(sqlite3_value* value) {
  auto type = sqlite3_value_type(value);
  PERFETTO_DCHECK(type == SQLITE_INTEGER);
  return static_cast<uint8_t>(sqlite3_value_int(value));
}

template <>
inline uint32_t ExtractSqliteValue(sqlite3_value* value) {
  auto type = sqlite3_value_type(value);
  PERFETTO_DCHECK(type == SQLITE_INTEGER);
  return static_cast<uint32_t>(sqlite3_value_int64(value));
}

template <>
inline uint64_t ExtractSqliteValue(sqlite3_value* value) {
  auto type = sqlite3_value_type(value);
  PERFETTO_DCHECK(type == SQLITE_INTEGER);
  return static_cast<uint64_t>(sqlite3_value_int64(value));
}

template <>
inline int64_t ExtractSqliteValue(sqlite3_value* value) {
  auto type = sqlite3_value_type(value);
  PERFETTO_DCHECK(type == SQLITE_INTEGER);
  return static_cast<int64_t>(sqlite3_value_int64(value));
}

template <>
inline double ExtractSqliteValue(sqlite3_value* value) {
  auto type = sqlite3_value_type(value);
  PERFETTO_DCHECK(type == SQLITE_FLOAT || type == SQLITE_INTEGER);
  return sqlite3_value_double(value);
}

// On MacOS size_t !== uint64_t
#if PERFETTO_BUILDFLAG(PERFETTO_OS_MACOSX)
template <>
inline size_t ExtractSqliteValue(sqlite3_value* value) {
  PERFETTO_DCHECK(sqlite3_value_type(value) == SQLITE_INTEGER);
  return static_cast<size_t>(sqlite3_value_int64(value));
}
#endif  // PERFETTO_BUILDFLAG(PERFETTO_OS_MACOSX)

template <typename T>
void ReportSqliteResult(sqlite3_context*, T value);

template <>
inline void ReportSqliteResult(sqlite3_context* ctx, int32_t value) {
  sqlite3_result_int(ctx, value);
}

template <>
inline void ReportSqliteResult(sqlite3_context* ctx, int64_t value) {
  sqlite3_result_int64(ctx, value);
}

template <>
inline void ReportSqliteResult(sqlite3_context* ctx, uint8_t value) {
  sqlite3_result_int(ctx, value);
}

template <>
inline void ReportSqliteResult(sqlite3_context* ctx, uint32_t value) {
  sqlite3_result_int64(ctx, value);
}

template <>
inline void ReportSqliteResult(sqlite3_context* ctx, uint64_t value) {
  sqlite3_result_int64(ctx, static_cast<sqlite_int64>(value));
}

template <>
inline void ReportSqliteResult(sqlite3_context* ctx, double value) {
  sqlite3_result_double(ctx, value);
}

inline std::string SqliteValueAsString(sqlite3_value* value) {
  switch (sqlite3_value_type(value)) {
    case SQLITE_INTEGER:
      return std::to_string(sqlite3_value_int64(value));
    case SQLITE_FLOAT:
      return std::to_string(sqlite3_value_double(value));
    case SQLITE_TEXT: {
      const char* str =
          reinterpret_cast<const char*>(sqlite3_value_text(value));
      return "'" + std::string(str) + "'";
    }
    default:
      PERFETTO_FATAL("Unknown value type %d", sqlite3_value_type(value));
  }
}

inline std::vector<Table::Column> GetColumnsForTable(
    sqlite3* db,
    const std::string& raw_table_name) {
  char sql[1024];
  const char kRawSql[] = "SELECT name, type from pragma_table_info(\"%s\")";

  // Support names which are table valued functions with arguments.
  std::string table_name = raw_table_name.substr(0, raw_table_name.find('('));
  int n = snprintf(sql, sizeof(sql), kRawSql, table_name.c_str());
  PERFETTO_DCHECK(n >= 0 || static_cast<size_t>(n) < sizeof(sql));

  sqlite3_stmt* raw_stmt = nullptr;
  int err = sqlite3_prepare_v2(db, sql, n, &raw_stmt, nullptr);

  ScopedStmt stmt(raw_stmt);
  PERFETTO_DCHECK(sqlite3_column_count(*stmt) == 2);

  std::vector<Table::Column> columns;
  for (;;) {
    err = sqlite3_step(raw_stmt);
    if (err == SQLITE_DONE)
      break;
    if (err != SQLITE_ROW) {
      PERFETTO_ELOG("Querying schema of table failed");
      return {};
    }

    const char* name =
        reinterpret_cast<const char*>(sqlite3_column_text(*stmt, 0));
    const char* raw_type =
        reinterpret_cast<const char*>(sqlite3_column_text(*stmt, 1));
    if (!name || !raw_type || !*name || !*raw_type) {
      PERFETTO_ELOG("Schema has invalid column values");
      return {};
    }

    Table::ColumnType type;
    if (strcmp(raw_type, "UNSIGNED BIG INT") == 0) {
      type = Table::ColumnType::kUlong;
    } else if (strcmp(raw_type, "UNSIGNED INT") == 0) {
      type = Table::ColumnType::kUint;
    } else if (strcmp(raw_type, "STRING") == 0) {
      type = Table::ColumnType::kString;
    } else {
      PERFETTO_FATAL("Unknown column type on table %s", raw_table_name.c_str());
    }
    columns.emplace_back(columns.size(), name, type);
  }
  return columns;
}

}  // namespace sqlite_utils
}  // namespace trace_processor
}  // namespace perfetto

#endif  // SRC_TRACE_PROCESSOR_SQLITE_UTILS_H_