PostgreSQLQuery+DataType.swift

/// PostgreSQL specific `SQLDataType`.
public struct PostgreSQLDataType: SQLDataType, Equatable {
    /// See `Equatable`.
    public static func == (lhs: PostgreSQLDataType, rhs: PostgreSQLDataType) -> Bool {
        // FIXME: more performant equatable is possible
        var binds: [Encodable] = []
        return lhs.serialize(&binds) == rhs.serialize(&binds)
    }
    
    /// See `SQLDataType`.
    public static func dataType(appropriateFor type: Any.Type) -> PostgreSQLDataType? {
        guard let type = type as? PostgreSQLDataTypeStaticRepresentable.Type else {
            return .jsonb
        }
        return type.postgreSQLDataType
    }
    
    /// signed eight-byte integer
    public static var int8: PostgreSQLDataType {
        return .bigint
    }
    
    /// signed eight-byte integer
    public static var bigint: PostgreSQLDataType {
        return .init(.bigint)
    }
    
    /// autoincrementing eight-byte integer
    public static var serial8: PostgreSQLDataType {
        return .bigserial
    }
    
    /// autoincrementing eight-byte integer
    public static var bigserial: PostgreSQLDataType {
        return .init(.bigserial)
    }
    
    /// fixed-length bit string
    public static var bit: PostgreSQLDataType {
        return .init(.bit(nil))
    }
    
    /// fixed-length bit string
    public static func bit(_ n: Int) -> PostgreSQLDataType {
        return .init(.bit(n))
    }
    
    /// variable-length bit string
    public static var varbit: PostgreSQLDataType {
        return .init(.varbit(nil))
    }
    
    /// variable-length bit string
    public static func varbit(_ n: Int) -> PostgreSQLDataType {
        return .init(.varbit(n))
    }
    
    /// logical Boolean (true/false)
    public static var bool: PostgreSQLDataType {
        return .boolean
    }
    
    /// logical Boolean (true/false)
    public static var boolean: PostgreSQLDataType {
        return .init(.boolean)
    }
    
    /// rectangular box on a plane
    public static var box: PostgreSQLDataType {
        return .init(.box)
    }
    
    /// binary data (“byte array”)
    public static var bytea: PostgreSQLDataType {
        return .init(.bytea)
    }
    
    /// fixed-length character string
    public static var char: PostgreSQLDataType {
        return .init(.char(nil))
    }
    
    /// fixed-length character string
    public static func char(_ n: Int) -> PostgreSQLDataType {
        return .init(.char(n))
    }
    
    /// variable-length character string
    public static var varchar: PostgreSQLDataType {
        return .init(.varchar(nil))
    }
    
    /// variable-length character string
    public static func varchar(_ n: Int) -> PostgreSQLDataType {
        return .init(.varchar(n))
    }
    
    /// IPv4 or IPv6 network address
    public static var cidr: PostgreSQLDataType {
        return .init(.cidr)
    }
    
    /// circle on a plane
    public static var circle: PostgreSQLDataType {
        return .init(.circle)
    }
    
    /// calendar date (year, month, day)
    public static var date: PostgreSQLDataType {
        return .init(.date)
    }
    
    /// floating-point number (8 bytes)
    public static var float8: PostgreSQLDataType {
        return .doublePrecision
    }
    
    /// floating-point number (8 bytes)
    public static var doublePrecision: PostgreSQLDataType {
        return .init(.doublePrecision)
    }
    
    /// IPv4 or IPv6 host address
    public static var inet: PostgreSQLDataType {
        return .init(.inet)
    }
    
    /// signed four-byte integer
    public static var int: PostgreSQLDataType {
        return .integer
    }
    
    /// signed four-byte integer
    public static var int4: PostgreSQLDataType {
        return .integer
    }
    
    /// signed four-byte integer
    public static var integer: PostgreSQLDataType {
        return .init(.integer)
    }
    
    /// time span
    public static var interval: PostgreSQLDataType {
        return .init(.interval)
    }
    
    /// textual JSON data
    public static var json: PostgreSQLDataType {
        return .init(.json)
    }
    
    /// binary JSON data, decomposed
    public static var jsonb: PostgreSQLDataType {
        return .init(.jsonb)
    }
    
    /// infinite line on a plane
    public static var line: PostgreSQLDataType {
        return .init(.line)
    }
    
    /// line segment on a plane
    public static var lseg: PostgreSQLDataType {
        return .init(.lseg)
    }
    
    /// MAC (Media Access Control) address
    public static var macaddr: PostgreSQLDataType {
        return .init(.macaddr)
    }
    
    /// MAC (Media Access Control) address (EUI-64 format)
    public static var macaddr8: PostgreSQLDataType {
        return .init(.macaddr8)
    }
    
    /// currency amount
    public static var money: PostgreSQLDataType {
        return .init(.money)
    }
    
    /// exact numeric of selectable precision
    public static var decimal: PostgreSQLDataType {
        return .init(.numeric(nil))
    }
    
    /// exact numeric of selectable precision
    public static func decimal(_ p: Int, _ s: Int) -> PostgreSQLDataType {
        return .init(.numeric((p, s)))
    }
    
    /// exact numeric of selectable precision
    public static func numeric(_ p: Int, _ s: Int) -> PostgreSQLDataType {
        return .init(.numeric((p, s)))
    }
    
    /// exact numeric of selectable precision
    public static var numeric: PostgreSQLDataType {
        return .init(.numeric(nil))
    }
    
    /// geometric path on a plane
    public static var path: PostgreSQLDataType {
        return .init(.path)
    }
    
    /// PostgreSQL Log Sequence Number
    public static var pgLSN: PostgreSQLDataType {
        return .init(.pgLSN)
    }
    
    /// geometric point on a plane
    public static var point: PostgreSQLDataType {
        return .init(.point)
    }
    
    /// closed geometric path on a plane
    public static var polygon: PostgreSQLDataType {
        return .init(.polygon)
    }
    
    /// single precision floating-point number (4 bytes)
    public static var float4: PostgreSQLDataType {
        return .real
    }
    
    /// single precision floating-point number (4 bytes)
    public static var real: PostgreSQLDataType {
        return .init(.real)
    }
    
    /// signed two-byte integer
    public static var int2: PostgreSQLDataType {
        return .smallint
    }
    
    /// signed two-byte integer
    public static var smallint: PostgreSQLDataType {
        return .init(.smallint)
    }
    
    /// autoincrementing two-byte integer
    public static var serial2: PostgreSQLDataType {
        return .smallserial
    }
    
    /// autoincrementing two-byte integer
    public static var smallserial: PostgreSQLDataType {
        return .init(.smallserial)
    }
    
    /// autoincrementing four-byte integer
    public static var serial4: PostgreSQLDataType {
        return .serial
    }
    
    /// autoincrementing four-byte integer
    public static var serial: PostgreSQLDataType {
        return .init(.serial)
    }
    
    /// variable-length character string
    public static var text: PostgreSQLDataType {
        return .init(.text)
    }
    
    /// time of day (no time zone)
    public static var time: PostgreSQLDataType {
        return .init(.time(nil))
    }
    
    /// time of day (no time zone)
    public static func time(_ n: Int) -> PostgreSQLDataType {
        return .init(.time(n))
    }
    
    /// time of day, including time zone
    public static var timetz: PostgreSQLDataType {
        return .init(.timetz(nil))
    }
    
    /// time of day, including time zone
    public static func timetz(_ n: Int) -> PostgreSQLDataType {
        return .init(.timetz(n))
    }
    
    /// date and time (no time zone)
    public static var timestamp: PostgreSQLDataType {
        return .init(.timestamp(nil))
    }
    
    /// date and time (no time zone)
    public static func timestamp(_ n: Int) -> PostgreSQLDataType {
        return .init(.timestamp(n))
    }
    
    /// date and time, including time zone
    public static var timestamptz: PostgreSQLDataType {
        return .init(.timestamptz(nil))
    }
    
    /// date and time, including time zone
    public static func timestamptz(_ n: Int) -> PostgreSQLDataType {
        return .init(.timestamptz(n))
    }
    
    /// text search query
    public static var tsquery: PostgreSQLDataType {
        return .init(.tsquery)
    }
    
    /// text search document
    public static var tsvector: PostgreSQLDataType {
        return .init(.tsvector)
    }
    
    /// user-level transaction ID snapshot
    public static var txidSnapshot: PostgreSQLDataType {
        return .init(.txidSnapshot)
    }
    
    /// universally unique identifier
    public static var uuid: PostgreSQLDataType {
        return .init(.uuid)
    }
    
    /// XML data
    public static var xml: PostgreSQLDataType {
        return .init(.xml)
    }
    
    /// User-defined type
    public static func custom(_ name: String) -> PostgreSQLDataType {
        return .init(.custom(name))
    }
    
    /// Creates an array type from a `PostgreSQLDataType`.
    public static func array(_ dataType: PostgreSQLDataType) -> PostgreSQLDataType {
        return .init(dataType.primitive, isArray: true)
    }
    
    let primitive: Primitive
    let isArray: Bool
    
    private init(_ primitive: Primitive, isArray: Bool = false) {
        self.primitive = primitive
        self.isArray = isArray
    }
    
    enum Primitive {
        /// signed eight-byte integer
        case bigint
        
        /// autoincrementing eight-byte integer
        case bigserial
        
        /// fixed-length bit string
        case bit(Int?)
        
        /// variable-length bit string
        case varbit(Int?)
        
        /// logical Boolean (true/false)
        case boolean
        
        /// rectangular box on a plane
        case box
        
        /// binary data (“byte array”)
        case bytea
        
        /// fixed-length character string
        case char(Int?)
        
        /// variable-length character string
        case varchar(Int?)
        
        /// IPv4 or IPv6 network address
        case cidr
        
        /// circle on a plane
        case circle
        
        /// calendar date (year, month, day)
        case date
        
        /// floating-point number (8 bytes)
        case doublePrecision
        
        /// IPv4 or IPv6 host address
        case inet
        
        /// signed four-byte integer
        case integer
        
        /// time span
        case interval
        
        /// textual JSON data
        case json
        
        /// binary JSON data, decomposed
        case jsonb
        
        /// infinite line on a plane
        case line
        
        /// line segment on a plane
        case lseg
        
        /// MAC (Media Access Control) address
        case macaddr
        
        /// MAC (Media Access Control) address (EUI-64 format)
        case macaddr8
        
        /// currency amount
        case money
        
        /// exact numeric of selectable precision
        case numeric((Int, Int)?)
        
        /// geometric path on a plane
        case path
        
        /// PostgreSQL Log Sequence Number
        case pgLSN
        
        /// geometric point on a plane
        case point
        
        /// closed geometric path on a plane
        case polygon
        
        /// single precision floating-point number (4 bytes)
        case real
        
        /// signed two-byte integer
        case smallint
        
        /// autoincrementing two-byte integer
        case smallserial
        
        /// autoincrementing four-byte integer
        case serial
        
        /// variable-length character string
        case text
        
        /// time of day (no time zone)
        case time(Int?)
        
        /// time of day, including time zone
        case timetz(Int?)
        
        /// date and time (no time zone)
        case timestamp(Int?)
        
        /// date and time, including time zone
        case timestamptz(Int?)
        
        /// text search query
        case tsquery
        
        /// text search document
        case tsvector
        
        /// user-level transaction ID snapshot
        case txidSnapshot
        
        /// universally unique identifier
        case uuid
        
        /// XML data
        case xml
        
        /// User-defined type
        case custom(String)
        
        /// See `SQLSerializable`.
        public func serialize(_ binds: inout [Encodable]) -> String {
            switch self {
            case .bigint: return "BIGINT"
            case .bigserial: return "BIGSERIAL"
            case .varbit(let n):
                if let n = n {
                    return "VARBIT(" + n.description + ")"
                } else {
                    return "VARBIT"
                }
            case .varchar(let n):
                if let n = n {
                    return "VARCHAR(" + n.description + ")"
                } else {
                    return "VARCHAR"
                }
            case .bit(let n):
                if let n = n {
                    return "BIT(" + n.description + ")"
                } else {
                    return "BIT"
                }
            case .boolean: return "BOOLEAN"
            case .box: return "BOX"
            case .bytea: return "BYTEA"
            case .char(let n):
                if let n = n {
                    return "CHAR(" + n.description + ")"
                } else {
                    return "CHAR"
                }
            case .cidr: return "CIDR"
            case .circle: return "CIRCLE"
            case .date: return "DATE"
            case .doublePrecision: return "DOUBLE PRECISION"
            case .inet: return "INET"
            case .integer: return "INTEGER"
            case .interval: return "INTEVERAL"
            case .json: return "JSON"
            case .jsonb: return "JSONB"
            case .line: return "LINE"
            case .lseg: return "LSEG"
            case .macaddr: return "MACADDR"
            case .macaddr8: return "MACADDER8"
            case .money: return "MONEY"
            case .numeric(let sp):
                if let sp = sp {
                    return "NUMERIC(" + sp.0.description + ", " + sp.1.description + ")"
                } else {
                    return "NUMERIC"
                }
            case .path: return "PATH"
            case .pgLSN: return "PG_LSN"
            case .point: return "POINT"
            case .polygon: return "POLYGON"
            case .real: return "REAL"
            case .smallint: return "SMALLINT"
            case .smallserial: return "SMALLSERIAL"
            case .serial: return "SERIAL"
            case .text: return "TEXT"
            case .time(let p):
                if let p = p {
                    return "TIME(" + p.description + ")"
                } else {
                    return "TIME"
                }
            case .timetz(let p):
                if let p = p {
                    return "TIMETZ(" + p.description + ")"
                } else {
                    return "TIMETZ"
                }
            case .timestamp(let p):
                if let p = p {
                    return "TIMESTAMP(" + p.description + ")"
                } else {
                    return "TIMESTAMP"
                }
            case .timestamptz(let p):
                if let p = p {
                    return "TIMESTAMPTZ(" + p.description + ")"
                } else {
                    return "TIMESTAMPTZ"
                }
            case .tsquery: return "TSQUERY"
            case .tsvector: return "TSVECTOR"
            case .txidSnapshot: return "TXID_SNAPSHOT"
            case .uuid: return "UUID"
            case .xml: return "XML"
            case .custom(let custom): return custom
            }
        }
    }
    
    /// See `SQLSerializable`.
    public func serialize(_ binds: inout [Encodable]) -> String {
        if isArray {
            return primitive.serialize(&binds) + "[]"
        } else {
            return primitive.serialize(&binds)
        }
    }
}