status-im/status-go

package protocol

import (
    "database/sql"
    "fmt"
    "strings"
)

const selectTimestampsQuery = "SELECT whisper_timestamp FROM user_messages WHERE %s whisper_timestamp >= ? AND whisper_timestamp <= ?"
const selectCountQuery = "SELECT COUNT(*) FROM user_messages WHERE %s whisper_timestamp >= ? AND whisper_timestamp <= ?"

func querySeveralChats(chatIDs []string) string {
    if len(chatIDs) == 0 {
        return ""
    }

    var conditions []string
    for _, chatID := range chatIDs {
        conditions = append(conditions, fmt.Sprintf("local_chat_id = '%s'", chatID))
    }
    return fmt.Sprintf("(%s) AND", strings.Join(conditions, " OR "))
}

func (db sqlitePersistence) SelectMessagesTimestampsForChatsByPeriod(chatIDs []string, startTimestamp uint64, endTimestamp uint64) ([]uint64, error) {
    query := fmt.Sprintf(selectTimestampsQuery, querySeveralChats(chatIDs))

    rows, err := db.db.Query(query, startTimestamp, endTimestamp)
    if err != nil {
        return []uint64{}, err
    }
    defer rows.Close()

    var timestamps []uint64
    for rows.Next() {
        var timestamp uint64
        err := rows.Scan(&timestamp)
        if err != nil {
            return nil, err
        }
        timestamps = append(timestamps, timestamp)
    }

    err = rows.Err()
    if err != nil {
        return []uint64{}, err
    }

    return timestamps, nil
}

func (db sqlitePersistence) SelectMessagesCountForChatsByPeriod(chatIDs []string, startTimestamp uint64, endTimestamp uint64) (int, error) {
    query := fmt.Sprintf(selectCountQuery, querySeveralChats(chatIDs))

    var count int
    if err := db.db.QueryRow(query, startTimestamp, endTimestamp).Scan(&count); err != nil {
        if err == sql.ErrNoRows {
            return 0, nil
        }
        return 0, err
    }

    return count, nil
}