(in-package #:clsql-sys)

(defclass command-object ()

((expression :accessor expression :initarg :expression :initform nil

:documentation "query that refers to parameters using \"$1\", \"$2\", \"$n\".

These match positions in the parameters list.")

(parameters :accessor parameters :initarg :parameters :initform nil

:documentation "list of parameters")

(prepared-name :accessor prepared-name :initarg :prepared-name :initform ""

:documentation "If we want this to be a prepared statement, give it a name

to identify it to this session")

(has-been-prepared :accessor has-been-prepared :initarg :has-been-prepared :initform nil

:documentation "Have we already prepared this command object?")

))

(defgeneric prepare-sql-parameter (sql-parameter)

(:documentation "This method is responsible for formatting parameters

as the database expects them (eg: :false is nil, nil is :null, dates are iso8601 strings)")

(:method (sql-parameter)

(typecase sql-parameter

(null :null)

(symbol

(if (member sql-parameter (list :false :F))

nil

(princ-to-string sql-parameter)))

(clsql-sys:date (format-date nil sql-parameter :format :iso8601))

(clsql-sys:wall-time (format-time nil sql-parameter :format :iso8601))

(t sql-parameter))))

(defmethod initialize-instance :after ((o command-object) &key &allow-other-keys )

;; Inits parameter value coersion

(setf (parameters o) (parameters o)))

(defmethod (setf parameters) (new (o command-object))

" This causes the semantics to match cl-sql instead of cl-postgresql

(setf (slot-value o 'parameters)

(loop for p in new collecting (prepare-sql-parameter p))))

(defun reset-command-object (co)

"Resets the command object to have no name and to be unprepared

(setf (prepared-name co) ""

(has-been-prepared co) nil))

(defun command-object (expression &optional parameters (prepared-name ""))

(make-instance 'command-object

:expression expression

:parameters parameters

:prepared-name prepared-name))