status-im/status-go

package ens

import (
    "database/sql"
)

type Database struct {
    db *sql.DB
}

type UsernameDetail struct {
    Username string `json:"username"`
    ChainID  uint64 `json:"chainId"`
    Clock    uint64 `json:"clock"`
    Removed  bool   `json:"removed"`
}

func NewEnsDatabase(db *sql.DB) *Database {
    return &Database{db: db}
}

func (db *Database) GetEnsUsernames(removed *bool) (result []*UsernameDetail, err error) {

    var sqlQuery = `SELECT username, chain_id, clock, removed  
                      FROM ens_usernames`

    var rows *sql.Rows
    if removed == nil {
        rows, err = db.db.Query(sqlQuery)
    } else {
        sqlQuery += " WHERE removed = ?"
        rows, err = db.db.Query(sqlQuery, removed)
    }

    if err != nil {
        return result, err
    }

    defer rows.Close()

    for rows.Next() {
        var ensUsername UsernameDetail
        err = rows.Scan(&ensUsername.Username, &ensUsername.ChainID, &ensUsername.Clock, &ensUsername.Removed)
        if err != nil {
            return nil, err
        }
        result = append(result, &ensUsername)
    }

    return result, nil
}

func (db *Database) AddEnsUsername(details *UsernameDetail) error {
    const sqlQuery = `INSERT OR REPLACE INTO ens_usernames(username, chain_id, clock, removed)
                      VALUES (?, ?, ?, ?)`
    _, err := db.db.Exec(sqlQuery, details.Username, details.ChainID, details.Clock, details.Removed)
    return err
}

func (db *Database) RemoveEnsUsername(details *UsernameDetail) (bool, error) {
    const sqlQuery = `UPDATE ens_usernames SET removed = 1, clock = ?  
                      WHERE username = (?) AND chain_id = ?`
    result, err := db.db.Exec(sqlQuery, details.Clock, details.Username, details.ChainID)
    if err != nil {
        return false, err
    }
    n, err := result.RowsAffected()
    if err != nil {
        return false, err
    }
    return n > 0, nil
}

func (db *Database) SaveOrUpdateEnsUsername(details *UsernameDetail) error {
    const sqlQuery = `INSERT OR REPLACE INTO ens_usernames (username, chain_id, clock, removed)
SELECT ?, ?, ?, ?
WHERE NOT EXISTS (SELECT 1 FROM ens_usernames WHERE username = ? AND chain_id = ? AND clock >= ?);`

    _, err := db.db.Exec(sqlQuery, details.Username, details.ChainID, details.Clock, details.Removed, details.Username, details.ChainID, details.Clock)
    return err
}