// Sources/iMessageMax/Database/QueryBuilder.swift
import Foundation
final class QueryBuilder {
private var selectCols: [String] = []
private var fromTable: String = ""
private var joins: [String] = []
private var conditions: [(String, [Any])] = []
private var groupByCols: [String] = []
private var havingConditions: [(String, [Any])] = []
private var orderByCols: [String] = []
private var limitValue: Int?
private var offsetValue: Int?
@discardableResult
func select(_ columns: String...) -> QueryBuilder {
selectCols.append(contentsOf: columns)
return self
}
@discardableResult
func from(_ table: String) -> QueryBuilder {
fromTable = table
return self
}
@discardableResult
func join(_ clause: String) -> QueryBuilder {
joins.append("JOIN \(clause)")
return self
}
@discardableResult
func leftJoin(_ clause: String) -> QueryBuilder {
joins.append("LEFT JOIN \(clause)")
return self
}
@discardableResult
func `where`(_ condition: String, _ params: Any...) -> QueryBuilder {
conditions.append((condition, params))
return self
}
@discardableResult
func groupBy(_ columns: String...) -> QueryBuilder {
groupByCols.append(contentsOf: columns)
return self
}
@discardableResult
func having(_ condition: String, _ params: Any...) -> QueryBuilder {
havingConditions.append((condition, params))
return self
}
@discardableResult
func orderBy(_ columns: String...) -> QueryBuilder {
orderByCols.append(contentsOf: columns)
return self
}
@discardableResult
func limit(_ n: Int) -> QueryBuilder {
limitValue = n
return self
}
@discardableResult
func offset(_ n: Int) -> QueryBuilder {
offsetValue = n
return self
}
func build() -> (sql: String, params: [Any]) {
var parts: [String] = []
var allParams: [Any] = []
// SELECT
parts.append("SELECT \(selectCols.joined(separator: ", "))")
// FROM
parts.append("FROM \(fromTable)")
// JOINs
parts.append(contentsOf: joins)
// WHERE
if !conditions.isEmpty {
let whereClauses = conditions.map { $0.0 }
parts.append("WHERE \(whereClauses.joined(separator: " AND "))")
for (_, params) in conditions {
allParams.append(contentsOf: params)
}
}
// GROUP BY
if !groupByCols.isEmpty {
parts.append("GROUP BY \(groupByCols.joined(separator: ", "))")
}
// HAVING
if !havingConditions.isEmpty {
let havingClauses = havingConditions.map { $0.0 }
parts.append("HAVING \(havingClauses.joined(separator: " AND "))")
for (_, params) in havingConditions {
allParams.append(contentsOf: params)
}
}
// ORDER BY
if !orderByCols.isEmpty {
parts.append("ORDER BY \(orderByCols.joined(separator: ", "))")
}
// LIMIT
if let limit = limitValue {
parts.append("LIMIT \(limit)")
}
// OFFSET
if let offset = offsetValue {
parts.append("OFFSET \(offset)")
}
return (parts.joined(separator: "\n"), allParams)
}
// MARK: - Utility
static func escapeLike(_ s: String) -> String {
s.replacingOccurrences(of: "\\", with: "\\\\")
.replacingOccurrences(of: "%", with: "\\%")
.replacingOccurrences(of: "_", with: "\\_")
}
}
