/**
 *    Copyright (C) 2012 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects
 *    for all of the code used other than as permitted herein. If you modify
 *    file(s) with this exception, you may extend this exception to your
 *    version of the file(s), but you are not obligated to do so. If you do not
 *    wish to do so, delete this exception statement from your version. If you
 *    delete this exception statement from all source files in the program,
 *    then also delete it in the license file.
 */

#pragma once

#include <string>

#include "mongo/base/disallow_copying.h"
#include "mongo/base/string_data.h"
#include "mongo/db/jsobj.h"

namespace mongo {

/**
 * This class represents the layout and contents of documents contained in the
 * config.collections collection. All manipulation of documents coming from that
 * collection should be done with this class.
 *
 * Usage Example:
 *
 *     // Contact the config. 'conn' has been obtained before.
 *     DBClientBase* conn;
 *     BSONObj query = QUERY(CollectionType::exampleField("exampleFieldName"));
 *     exampleDoc = conn->findOne(CollectionType::ConfigNS, query);
 *
 *     // Process the response.
 *     CollectionType exampleType;
 *     std::string errMsg;
 *     if (!exampleType.parseBSON(exampleDoc, &errMsg) || !exampleType.isValid(&errMsg)) {
 *         // Can't use 'exampleType'. Take action.
 *     }
 *     // use 'exampleType'
 *
 */
class CollectionType {
    MONGO_DISALLOW_COPYING(CollectionType);

public:
    //
    // schema declarations
    //

    // Name of the collections collection in the config server.
    static const std::string ConfigNS;

    // Field names and types in the collections collection type.
    static const BSONField<std::string> ns;
    static const BSONField<std::string> primary;
    static const BSONField<BSONObj> keyPattern;
    static const BSONField<bool> unique;
    static const BSONField<Date_t> updatedAt;
    static const BSONField<bool> noBalance;
    static const BSONField<OID> epoch;
    static const BSONField<bool> dropped;
    static const BSONField<OID> DEPRECATED_lastmodEpoch;
    static const BSONField<Date_t> DEPRECATED_lastmod;

    //
    // collections type methods
    //

    CollectionType();
    ~CollectionType();

    /**
     * Returns true if all the mandatory fields are present and have valid
     * representations. Otherwise returns false and fills in the optional 'errMsg' string.
     */
    bool isValid(std::string* errMsg) const;

    /**
     * Returns the BSON representation of the entry.
     */
    BSONObj toBSON() const;

    /**
     * Clears and populates the internal state using the 'source' BSON object if the
     * latter contains valid values. Otherwise sets errMsg and returns false.
     */
    bool parseBSON(const BSONObj& source, std::string* errMsg);

    /**
     * Clears the internal state.
     */
    void clear();

    /**
     * Copies all the fields present in 'this' to 'other'.
     */
    void cloneTo(CollectionType* other) const;

    /**
     * Returns a std::string representation of the current internal state.
     */
    std::string toString() const;

    //
    // individual field accessors
    //

    // Mandatory Fields
    void setNS(const StringData& ns) {
        _ns = ns.toString();
        _isNsSet = true;
    }

    void unsetNS() {
        _isNsSet = false;
    }

    bool isNSSet() const {
        return _isNsSet;
    }

    // Calling get*() methods when the member is not set results in undefined behavior
    const std::string getNS() const {
        dassert(_isNsSet);
        return _ns;
    }

    void setUpdatedAt(const Date_t updatedAt) {
        _updatedAt = updatedAt;
        _isUpdatedAtSet = true;
    }

    void unsetUpdatedAt() {
        _isUpdatedAtSet = false;
    }

    bool isUpdatedAtSet() const {
        return _isUpdatedAtSet;
    }

    // Calling get*() methods when the member is not set results in undefined behavior
    const Date_t getUpdatedAt() const {
        dassert(_isUpdatedAtSet);
        return _updatedAt;
    }

    void setEpoch(const OID epoch) {
        _epoch = epoch;
        _isEpochSet = true;
    }

    void unsetEpoch() {
        _isEpochSet = false;
    }

    bool isEpochSet() const {
        return _isEpochSet;
    }

    // Calling get*() methods when the member is not set results in undefined behavior
    const OID getEpoch() const {
        dassert(_isEpochSet);
        return _epoch;
    }

    // Optional Fields
    void setPrimary(StringData& primary) {
        _primary = primary.toString();
        _isPrimarySet = true;
    }

    void unsetPrimary() {
        _isPrimarySet = false;
    }

    bool isPrimarySet() const {
        return _isPrimarySet || primary.hasDefault();
    }

    // Calling get*() methods when the member is not set and has no default results in undefined
    // behavior
    std::string getPrimary() const {
        if (_isPrimarySet) {
            return _primary;
        } else {
            dassert(primary.hasDefault());
            return primary.getDefault();
        }
    }
    void setKeyPattern(const BSONObj& keyPattern) {
        _keyPattern = keyPattern.getOwned();
        _isKeyPatternSet = true;
    }

    void unsetKeyPattern() {
        _isKeyPatternSet = false;
    }

    bool isKeyPatternSet() const {
        return _isKeyPatternSet || keyPattern.hasDefault();
    }

    // Calling get*() methods when the member is not set and has no default results in undefined
    // behavior
    BSONObj getKeyPattern() const {
        if (_isKeyPatternSet) {
            return _keyPattern;
        } else {
            dassert(keyPattern.hasDefault());
            return keyPattern.getDefault();
        }
    }
    void setUnique(bool unique) {
        _unique = unique;
        _isUniqueSet = true;
    }

    void unsetUnique() {
        _isUniqueSet = false;
    }

    bool isUniqueSet() const {
        return _isUniqueSet || unique.hasDefault();
    }

    // Calling get*() methods when the member is not set and has no default results in undefined
    // behavior
    bool getUnique() const {
        if (_isUniqueSet) {
            return _unique;
        } else {
            dassert(unique.hasDefault());
            return unique.getDefault();
        }
    }
    void setNoBalance(bool noBalance) {
        _noBalance = noBalance;
        _isNoBalanceSet = true;
    }

    void unsetNoBalance() {
        _isNoBalanceSet = false;
    }

    bool isNoBalanceSet() const {
        return _isNoBalanceSet || noBalance.hasDefault();
    }

    // Calling get*() methods when the member is not set and has no default results in undefined
    // behavior
    bool getNoBalance() const {
        if (_isNoBalanceSet) {
            return _noBalance;
        } else {
            dassert(noBalance.hasDefault());
            return noBalance.getDefault();
        }
    }
    void setDropped(bool dropped) {
        _dropped = dropped;
        _isDroppedSet = true;
    }

    void unsetDropped() {
        _isDroppedSet = false;
    }

    bool isDroppedSet() const {
        return _isDroppedSet || dropped.hasDefault();
    }

    // Calling get*() methods when the member is not set and has no default results in undefined
    // behavior
    bool getDropped() const {
        if (_isDroppedSet) {
            return _dropped;
        } else {
            dassert(dropped.hasDefault());
            return dropped.getDefault();
        }
    }

private:
    // Convention: (M)andatory, (O)ptional, (S)pecial rule.
    std::string _ns;  // (M)  namespace
    bool _isNsSet;
    std::string _primary;  // (O)  either/or with _keyPattern
    bool _isPrimarySet;
    BSONObj _keyPattern;  // (O)  sharding pattern if sharded
    bool _isKeyPatternSet;
    bool _unique;  // (O)  mandatory if sharded, index is unique
    bool _isUniqueSet;
    Date_t _updatedAt;  // (M)  last updated time
    bool _isUpdatedAtSet;
    bool _noBalance;  // (O)  optional if sharded, disable balancing
    bool _isNoBalanceSet;
    OID _epoch;  // (M)  disambiguates collection incarnations
    bool _isEpochSet;
    bool _dropped;  // (O)  if true, ignore this entry
    bool _isDroppedSet;
};

}  // namespace mongo
