// Copyright (c) 2019-2022 The Bitcoin Core developers

// Distributed under the MIT software license, see the accompanying

// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#ifndef BITCOIN_COMMON_SETTINGS_H

#define BITCOIN_COMMON_SETTINGS_H

#include <util/fs.h>

#include <cstddef>

#include <map>

#include <string>

#include <vector>

class UniValue;

namespace common {

//! Settings value type (string/integer/boolean/null variant).

//!

//! @note UniValue is used here for convenience and because it can be easily

//!       serialized in a readable format. But any other variant type that can

//!       be assigned strings, int64_t, and bool values and has get_str(),

//!       getInt<int64_t>(), get_bool(), isNum(), isBool(), isFalse(), isTrue() and

//!       isNull() methods can be substituted if there's a need to move away

//!       from UniValue. (An implementation with boost::variant was posted at

//!       https://github.com/bitcoin/bitcoin/pull/15934/files#r337691812)

using SettingsValue = UniValue;

//! Stored settings. This struct combines settings from the command line, a

//! read-only configuration file, and a read-write runtime settings file.

struct Settings {

    //! Map of setting name to forced setting value.

    std::map<std::string, SettingsValue> forced_settings;

    //! Map of setting name to list of command line values.

    std::map<std::string, std::vector<SettingsValue>> command_line_options;

    //! Map of setting name to read-write file setting value.

    std::map<std::string, SettingsValue> rw_settings;

    //! Map of config section name and setting name to list of config file values.

    std::map<std::string, std::map<std::string, std::vector<SettingsValue>>> ro_config;

};

//! Read settings file.

bool ReadSettings(const fs::path& path,

    std::map<std::string, SettingsValue>& values,

    std::vector<std::string>& errors);

//! Write settings file.

bool WriteSettings(const fs::path& path,

    const std::map<std::string, SettingsValue>& values,

    std::vector<std::string>& errors);

//! Get settings value from combined sources: forced settings, command line

//! arguments, runtime read-write settings, and the read-only config file.

//!

//! @param ignore_default_section_config - ignore values in the default section

//!                                        of the config file (part before any

//!                                        [section] keywords)

//! @param ignore_nonpersistent - ignore non-persistent settings values (forced

//!                               settings values and values specified on the

//!                               command line). Only return settings in the

//!                               read-only config and read-write settings

//!                               files.

//! @param get_chain_type - enable special backwards compatible behavior

//!                         for GetChainType

SettingsValue GetSetting(const Settings& settings,

    const std::string& section,

    const std::string& name,

    bool ignore_default_section_config,

    bool ignore_nonpersistent,

    bool get_chain_type);

//! Get combined setting value similar to GetSetting(), except if setting was

//! specified multiple times, return a list of all the values specified.

std::vector<SettingsValue> GetSettingsList(const Settings& settings,

    const std::string& section,

    const std::string& name,

    bool ignore_default_section_config);

//! Return true if a setting is set in the default config file section, and not

//! overridden by a higher priority command-line or network section value.

//!

//! This is used to provide user warnings about values that might be getting

//! ignored unintentionally.

bool OnlyHasDefaultSectionSetting(const Settings& settings, const std::string& section, const std::string& name);

//! Accessor for list of settings that skips negated values when iterated over.

//! The last boolean `false` value in the list and all earlier values are

//! considered negated.

struct SettingsSpan {

    explicit SettingsSpan() = default;

    explicit SettingsSpan(const SettingsValue& value) noexcept : SettingsSpan(&value, 1) {}

    explicit SettingsSpan(const SettingsValue* data, size_t size) noexcept : data(data), size(size) {}

    explicit SettingsSpan(const std::vector<SettingsValue>& vec) noexcept;

    const SettingsValue* begin() const; //!< Pointer to first non-negated value.

    const SettingsValue* end() const;   //!< Pointer to end of values.

    bool empty() const;                 //!< True if there are any non-negated values.

    bool last_negated() const;          //!< True if the last value is negated.

    size_t negated() const;             //!< Number of negated values.

    const SettingsValue* data = nullptr;

    size_t size = 0;

};

//! Map lookup helper.

template <typename Map, typename Key>

auto FindKey(Map&& map, Key&& key) -> decltype(&map.at(key))

{

    auto it = map.find(key);

    return it == map.end() ? nullptr : &it->second;

}

Unexecuted instantiation: _ZN6common7FindKeyIRSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESt6vectorI8UniValueSaIS9_EESt4lessIS7_ESaISt4pairIKS7_SB_EEERA12_KcEEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRKSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE8UniValueSt4lessIS7_ESaISt4pairIKS7_S8_EEERSC_EEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRKSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESt6vectorI8UniValueSaIS9_EESt4lessIS7_ESaISt4pairIKS7_SB_EEERSF_EEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRKSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES1_IS7_St6vectorI8UniValueSaIS9_EESt4lessIS7_ESaISt4pairIKS7_SB_EEESD_SaISE_ISF_SI_EEERSF_EEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRKSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES1_IS7_St6vectorI8UniValueSaIS9_EESt4lessIS7_ESaISt4pairIKS7_SB_EEESD_SaISE_ISF_SI_EEERA1_KcEEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEES1_IS7_St6vectorI8UniValueSaIS9_EESt4lessIS7_ESaISt4pairIKS7_SB_EEESD_SaISE_ISF_SI_EEERSF_EEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRSt3mapISt7variantIJ14CNoDestination17PubKeyDestination6PKHash10ScriptHash19WitnessV0ScriptHash16WitnessV0KeyHash16WitnessV1Taproot11PayToAnchor14WitnessUnknownEEN6wallet16CAddressBookDataESt4lessISC_ESaISt4pairIKSC_SE_EEERSI_EEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRKSt3mapISt7variantIJ14CNoDestination17PubKeyDestination6PKHash10ScriptHash19WitnessV0ScriptHash16WitnessV0KeyHash16WitnessV1Taproot11PayToAnchor14WitnessUnknownEEN6wallet16CAddressBookDataESt4lessISC_ESaISt4pairIKSC_SE_EEERSI_EEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEESt6vectorI8UniValueSaIS9_EESt4lessIS7_ESaISt4pairIKS7_SB_EEERSF_EEDTadcldtfp_2atfp0_EEOT_OT0_

Unexecuted instantiation: _ZN6common7FindKeyIRSt3mapINSt7__cxx1112basic_stringIcSt11char_traitsIcESaIcEEE8UniValueSt4lessIS7_ESaISt4pairIKS7_S8_EEERSC_EEDTadcldtfp_2atfp0_EEOT_OT0_

} // namespace common

#endif // BITCOIN_COMMON_SETTINGS_H