Added a few attributes that are nice n easy to use for common cases

[clinton/lisp-on-lines.git] / src / mewa.lisp

(declaim (optimize (speed 2) (space 3) (safety 0)))

(in-package :lisp-on-lines)

(defparameter *default-type* :ucw)

(define-layered-class description ()
  ((description-type
    :initarg :type
    :accessor description.type
    :initform 'viewer
    :special t)
   (description-layers
    :initarg :layers
    :accessor description.layers
    :initform nil
    :special t)
   (description-properties
    :accessor description.properties
    :initform nil
    :special t)
   (described-object
    :layered-accessor object
    :initform nil
    :special t)
   (description-attributes
    :accessor attributes
    :initarg :attributes
    :initform nil
    :special t)))

(defmethod print-object ((self description) stream)
  (print-unreadable-object (self stream :type t)
    (with-slots (description-type) self
      (format t "~A" description-type))))

;;;; * Occurences

(defvar *occurence-map* (make-hash-table)
  "a display is generated by associating an 'occurence' 
with an instance of a class. This is usually keyed off class-name,
although an arbitrary occurence can be used with an arbitrary class.")

(define-layered-class
    standard-occurence (description)
    ((attribute-map :accessor attribute-map :initform (make-hash-table)))
    (:documentation
     "an occurence holds the attributes like a class holds slot-definitions.
Attributes are the metadata used to display, validate, and otherwise manipulate actual values stored in lisp objects."))

(defun find-or-create-occurence (name)
  "Returns the occurence associated with this name."
  (let ((occurence (gethash name *occurence-map*)))
    (if occurence
	occurence
	(let ((new-occurence (make-instance 'standard-occurence)))
	  (setf (gethash name *occurence-map*) new-occurence)
	  new-occurence))))

(defun clear-occurence (occurence)
  "removes all attributes from the occurence"
  (setf (attribute-map occurence) (make-hash-table)))

(defgeneric find-occurence (name)
  (:method (thing)
    nil)
  (:method ((name symbol))
    (find-or-create-occurence name))
  (:method ((instance standard-object))
    (find-or-create-occurence (class-name (class-of instance)))))


(define-layered-class
    attribute (description)
    ((attribute-name :layered-accessor attribute.name
	   :initarg :name
	   :initform (gensym "ATTRIBUTE-")
	   :special t)
     (occurence :accessor occurence :initarg :occurence :initform nil)
     (label :initarg :label :layered-accessor label :initform nil :special t)))

;;;; * Attributes
(defmethod print-object ((self attribute) stream)
  (print-unreadable-object (self stream :type t)
    (with-slots (name description-type) self
      (format stream "~A ~A" description-type name))))

(define-layered-class
    standard-attribute (attribute)
    ((setter :accessor setter :initarg :setter :special t :initform nil)
     (getter :accessor getter :initarg :getter :special t :initform nil)
     (slot-name :accessor slot-name :initarg :slot-name :special t)
     (id :accessor id :initarg :id :special t :initform (random-string)))
    (:documentation "Attributes are used to display a part of a thing, such as a slot of an object, a text label, the car of a list, etc."))

(defmacro defattribute (name supers slots &rest args)
  (let* (
	(type-provided-p (second (assoc :type-name args)))
	(type (or type-provided-p name))
	(layer (or (second (assoc :in-layer args)) nil))
	(properties (cdr (assoc :default-properties args)))
	(cargs  (remove-if #'(lambda (key)
		   (or (eql key :type-name)
		       (eql key :default-properties)
		       (eql key :default-initargs)
		       (eql key :in-layer)))
			 args
	       :key #'car)))
    
    `(progn
      (define-layered-class
	  ;;;; TODO: fix the naive way of making sure s-a is a superclass
	  ;;;; Need some MOPey goodness.
	  ,name ,@ (when layer `(:in-layer ,layer)),(or supers '(standard-attribute))
	  ,(append slots (properties-as-slots properties)) 
	  #+ (or) ,@ (cdr cargs)
	  ,@cargs
	  (:default-initargs :properties (list ,@properties)
	    ,@ (cdr (assoc :default-initargs args))))

      ,(unless (not type-provided-p)
	`(defmethod find-attribute-class-for-type ((type (eql ',type)))
	   ',name)))))

(define-layered-class
    display-attribute (attribute)
    ()
    (:documentation "Presentation Attributes are used to display objects 
using the attributes defined in an occurence. Presentation Attributes are always named using keywords."))

(defun clear-attributes (name)
  "removes all attributes from an occurance"
  (clear-occurence (find-occurence name)))

(defmethod find-attribute-class-for-type (type)
  nil)

(defmethod find-attribute-class-for-name (name)
  "presentation attributes are named using keywords"
  (if (keywordp name)
      'display-attribute
      'standard-attribute))

(defun make-attribute (&rest args &key name type &allow-other-keys)
  (apply #'make-instance
	 (or (find-attribute-class-for-type type)
	     (find-attribute-class-for-name name))
	 args)) 

(defmethod ensure-attribute ((occurence standard-occurence) &rest args &key name &allow-other-keys)
  "Creates an attribute in the given occurence"
  (let ((attribute (apply #'make-attribute :occurence occurence args)))
    (setf (description.properties attribute) args)
    (setf (gethash name (attribute-map occurence))
	  attribute)))

(defmethod find-attribute ((occurence standard-occurence) name)
  (gethash name (attribute-map occurence)))

(defmethod find-all-attributes ((occurence standard-occurence))
  (loop for att being the hash-values of (attribute-map occurence)
	collect att))

(defmethod ensure-attribute (occurence-name &rest args &key name type &allow-other-keys)
  (declare (ignore name type))
  (apply #'ensure-attribute
   (find-occurence occurence-name)
   args)) 

;;;; The following functions make up the public interface to the
;;;; MEWA Attribute Occurence system.

(defmethod find-all-attributes (occurence-name)
  (find-all-attributes (find-occurence occurence-name)))

(defmethod find-attribute (occurence-name attribute-name)
  "Return the ATTRIBUTE named by ATTRIBUTE-NAME in OCCURANCE-name"
  (find-attribute (find-occurence occurence-name) attribute-name))

(defmethod (setf find-attribute) ((attribute-spec list) occurence-name attribute-name)
  "Create a new attribute in the occurence.
ATTRIBUTE-SPEC: a list of (type name &rest initargs)"
  (apply #'ensure-attribute occurence-name :name attribute-name :type (first attribute-spec) (rest attribute-spec)))


(defmethod find-attribute ((attribute-with-occurence attribute) attribute-name)
  (find-attribute (occurence attribute-with-occurence) attribute-name))

(defmethod set-attribute-properties ((occurence-name t) attribute properties)
  (setf (description.properties attribute) (plist-nunion
					    properties
					    (description.properties attribute)))
  (loop for (initarg value) on (description.properties attribute) 
	      by #'cddr
	      with map = (initargs.slot-names attribute)
	      do (let ((s-n (assoc-if #'(lambda (x) (member initarg x)) map)))
		   
		   (if s-n
		       (progn
			 (setf (slot-value attribute
					   (cdr s-n))
			       value))
		       (warn "Cannot find initarg ~A in attribute ~S" initarg attribute)))
	      finally (return attribute)))

(defmethod set-attribute (occurence-name attribute-name attribute-spec &key (inherit t))
  "If inherit is T, sets the properties of the attribute only, unless the type has changed.
otherwise, (setf find-attribute)"
  (let ((att (find-attribute occurence-name attribute-name)))
    (if (and att inherit (or (eql (car attribute-spec)
			      (description.type att))
			     (eq (car attribute-spec) t)))
	(set-attribute-properties occurence-name att (cdr attribute-spec))
	(setf (find-attribute occurence-name attribute-name)
	      (cons  (car attribute-spec)
		     (plist-nunion
		      (cdr attribute-spec) 
		      (when att (description.properties att))))))))

(defmethod perform-define-attributes ((occurence-name t) attributes)
  (loop for attribute in attributes
	do (destructuring-bind (name type &rest args)
		  attribute
	     (cond ((not (null type))
		    ;;set the type as well
		    (set-attribute occurence-name name (cons type args)))))))
		       
(defmacro define-attributes (occurence-names &body attribute-definitions)
  `(progn
    ,@(loop for occurence-name in occurence-names
	    collect `(perform-define-attributes (quote ,occurence-name) (quote ,attribute-definitions)))))

(defmethod find-display-attribute (occurence name)
  (find-attribute occurence (intern (symbol-name name) "KEYWORD")))

(defmethod find-description (object type)
  (let ((occurence (find-occurence object)))
    (or (find-display-attribute
	 occurence
	 type)
	occurence)))

(defmethod setter (attribute)
  (warn "Setting ~A in ~A" attribute *context*)
  (let ((setter (getf (description.properties attribute) :setter))
	(slot-name (getf (description.properties attribute) :slot-name)))
    (cond (setter
	   setter)
	  (slot-name
	   #'(lambda (value object)
	       (setf (slot-value object slot-name) value)))
	  (t
	   #'(lambda (value object)
	       (warn "Can't find anywere to set ~A in ~A using ~A" value object attribute))))))
    

(define-layered-function attribute-value (instance attribute)
  (:documentation " Like SLOT-VALUE for instances, the base method calls GETTER."))

(define-layered-method attribute-value (instance (attribute standard-attribute))
    (with-slots (getter slot-name) attribute 
      (cond ((and (slot-boundp attribute 'getter) getter) 
	     (funcall getter instance))
	    ((and (slot-boundp attribute 'slot-name) slot-name)
	     (when (slot-boundp instance slot-name)
		 (slot-value instance slot-name)))
	    ((and (slot-exists-p instance (attribute.name attribute)) )
	       (when (slot-boundp instance (attribute.name attribute))
		 (slot-value instance (attribute.name attribute)))))))

(define-layered-function (setf attribute-value) (value instance attribute))

(define-layered-method
    (setf attribute-value) (value instance (attribute standard-attribute))
  (with-slots (setter slot-name) attribute 
    (cond ((and (slot-boundp attribute 'setter) setter)

	   (funcall setter value instance))
	  ((and (slot-boundp attribute 'slot-name) slot-name)
	   (setf (slot-value instance slot-name) value))
	  ((and (slot-exists-p instance (attribute.name attribute)) slot-name)
	   (setf (slot-value instance (attribute.name attribute)) value))
	  (t
	   (error "Cannot set ~A in ~A" attribute instance)))))



;;;; ** Default Attributes


;;;; The default mewa class contains the types use as defaults.
;;;; maps meta-model slot-types to slot-presentation

(defvar *default-attributes-class-name* 'default)

(defmacro with-default-attributes ((occurence-name) &body body)
  `(let ((*default-attributes-class-name* ',occurence-name))
    ,@body))

(define-attributes (default)
  (boolean mewa-boolean)
  (string mewa-string)
  (number mewa-currency)
  (integer   mewa-integer)
  (currency  mewa-currency)
  (clsql:generalized-boolean mewa-boolean)
  (foreign-key foreign-key)
  (:viewer mewa-viewer)
  (:editor mewa-editor)
  (:creator mewa-creator)
  (:as-string mewa-one-line-presentation)
  (:one-line mewa-one-line-presentation)
  (:listing mewa-list-presentation :global-properties (:editablep nil) :editablep t)
  (:search-model mewa-object-presentation))

(defun find-presentation-attributes (occurence-name)
  (loop for att in (find-all-attributes occurence-name)
	when (typep att 'display-attribute)
	 collect att))

(defun attribute-to-definition (attribute)
  (nconc (list (attribute.name attribute)
	       (description.type attribute))
	 (description.properties attribute)))

(defun find-default-presentation-attribute-definitions ()
  (if (eql *default-attributes-class-name* 'default)
      (mapcar #'attribute-to-definition (find-presentation-attributes 'default)) 
      (remove-duplicates (mapcar #'attribute-to-definition
				 (append
				  (find-presentation-attributes 'default)
				  (find-presentation-attributes
				   *default-attributes-class-name*))))))
(defun gen-ptype (type)
  (let* ((type (if (consp type) (car type) type))
	 (possible-default (find-attribute *default-attributes-class-name* type))
	 (real-default (find-attribute 'default type)))
    (cond
      (possible-default
	(description.type possible-default))
       (real-default
	(description.type real-default))
       (t type))))

(defun gen-presentation-slots (instance)
  (mapcar #'(lambda (x) (gen-pslot (cadr x) 
				   (string (car x)) 
				   (car x))) 
	  (meta-model:list-slot-types instance)))


(defun gen-pslot (type label slot-name)
  (copy-list `(,(gen-ptype type) 
	       :label ,label
	       :slot-name ,slot-name))) 

;; This software is Copyright (c) Drew Crampsie, 2004-2005.
;; You are granted the rights to distribute
;; and use this software as governed by the terms
;; of the Lisp Lesser GNU Public License
;; (http://opensource.franz.com/preamble.html),
;; known as the LLGPL.