content: ordered block document + edit ops + 40 tests

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

lib/content/doc.sx

@@ -0,0 +1,194 @@
+;; content-on-sx — ordered block document on Smalltalk-on-SX.
+;;
+;; A document (CtDoc) is a Smalltalk object holding an ordered sequence of block
+;; objects. Editing is a stream of ops (data dicts); doc-apply interprets one op
+;; and returns a NEW document — the input is never mutated, so any version is the
+;; head of an op stream (replay-friendly for persist + CRDT merge).
+;;
+;; Op shapes (data, not objects — they are the persist event payload):
+;;   {:op "insert" :block <blk> :after <id|nil>}   ; after nil = prepend
+;;   {:op "update" :id <id> :field <name> :value <v>}
+;;   {:op "move"   :id <id> :index <n>}
+;;   {:op "delete" :id <id>}
+
+(define
+  content-bootstrap-doc!
+  (fn
+    ()
+    (begin
+      (st-class-define! "CtDoc" "Object" (list "id" "blocks"))
+      (ct-def-method! "CtDoc" "id" "id ^ id")
+      (ct-def-method! "CtDoc" "blocks" "blocks ^ blocks")
+      (ct-def-method! "CtDoc" "type" "type ^ #document")
+      true)))
+
+;; ── construction ──
+(define
+  doc-new
+  (fn
+    (id blocks)
+    (st-iv-set!
+      (st-iv-set! (st-make-instance "CtDoc") "id" id)
+      "blocks"
+      blocks)))
+
+(define doc-empty (fn (id) (doc-new id (list))))
+
+;; ── accessors (message dispatch) ──
+(define doc-id (fn (doc) (st-send doc "id" (list))))
+(define doc-type (fn (doc) (str (st-send doc "type" (list)))))
+(define doc-blocks (fn (doc) (st-send doc "blocks" (list))))
+(define doc-count (fn (doc) (len (doc-blocks doc))))
+(define doc-block-at (fn (doc i) (nth (doc-blocks doc) i)))
+
+(define doc? (fn (v) (and (st-instance? v) (= (get v :class) "CtDoc"))))
+
+;; ── list helpers over block sequences ──
+(define
+  ct-index-loop
+  (fn
+    (blocks id i)
+    (cond
+      ((= (len blocks) 0) -1)
+      ((= (blk-id (first blocks)) id) i)
+      (else (ct-index-loop (rest blocks) id (+ i 1))))))
+
+(define ct-index-of (fn (blocks id) (ct-index-loop blocks id 0)))
+
+(define
+  ct-insert-at
+  (fn
+    (blocks i x)
+    (cond
+      ((= i 0) (cons x blocks))
+      ((= (len blocks) 0) (list x))
+      (else
+        (cons
+          (first blocks)
+          (ct-insert-at (rest blocks) (- i 1) x))))))
+
+(define
+  ct-remove-id
+  (fn
+    (blocks id)
+    (filter (fn (b) (if (= (blk-id b) id) false true)) blocks)))
+
+(define
+  ct-replace-id
+  (fn
+    (blocks id f)
+    (map (fn (b) (if (= (blk-id b) id) (f b) b)) blocks)))
+
+;; ── query ──
+(define doc-index-of (fn (doc id) (ct-index-of (doc-blocks doc) id)))
+
+(define
+  doc-find
+  (fn
+    (doc id)
+    (let
+      ((hits (filter (fn (b) (= (blk-id b) id)) (doc-blocks doc))))
+      (if (= (len hits) 0) nil (first hits)))))
+
+(define
+  doc-has?
+  (fn (doc id) (if (= (doc-index-of doc id) -1) false true)))
+
+;; ── structural edits (each returns a new document) ──
+(define doc-with-blocks (fn (doc blocks) (st-iv-set! doc "blocks" blocks)))
+
+(define
+  doc-append
+  (fn
+    (doc block)
+    (doc-with-blocks doc (append (doc-blocks doc) (list block)))))
+
+(define
+  doc-insert-at
+  (fn
+    (doc block i)
+    (doc-with-blocks doc (ct-insert-at (doc-blocks doc) i block))))
+
+(define
+  doc-insert-after
+  (fn
+    (doc block after-id)
+    (let
+      ((blocks (doc-blocks doc)))
+      (if
+        (= after-id nil)
+        (doc-with-blocks doc (cons block blocks))
+        (let
+          ((idx (ct-index-of blocks after-id)))
+          (if
+            (= idx -1)
+            (doc-with-blocks doc (append blocks (list block)))
+            (doc-with-blocks
+              doc
+              (ct-insert-at blocks (+ idx 1) block))))))))
+
+(define
+  doc-update
+  (fn
+    (doc id field value)
+    (doc-with-blocks
+      doc
+      (ct-replace-id (doc-blocks doc) id (fn (b) (blk-set b field value))))))
+
+(define
+  doc-delete
+  (fn (doc id) (doc-with-blocks doc (ct-remove-id (doc-blocks doc) id))))
+
+(define
+  doc-move
+  (fn
+    (doc id i)
+    (let
+      ((blk (doc-find doc id)))
+      (if
+        (= blk nil)
+        doc
+        (doc-with-blocks
+          doc
+          (ct-insert-at (ct-remove-id (doc-blocks doc) id) i blk))))))
+
+;; ── op constructors (data payload, reused by persist op log) ──
+(define op-insert (fn (block after) {:after after :op "insert" :block block}))
+
+(define op-update (fn (id field value) {:field field :id id :op "update" :value value}))
+
+(define op-move (fn (id index) {:id id :op "move" :index index}))
+
+(define op-delete (fn (id) {:id id :op "delete"}))
+
+;; ── op interpreter ──
+(define
+  doc-apply
+  (fn
+    (doc op)
+    (let
+      ((kind (get op :op)))
+      (cond
+        ((= kind "insert")
+          (doc-insert-after doc (get op :block) (get op :after)))
+        ((= kind "update")
+          (doc-update doc (get op :id) (get op :field) (get op :value)))
+        ((= kind "move") (doc-move doc (get op :id) (get op :index)))
+        ((= kind "delete") (doc-delete doc (get op :id)))
+        (else (error (str "unknown op: " kind)))))))
+
+(define
+  doc-apply-all
+  (fn
+    (doc ops)
+    (if
+      (= (len ops) 0)
+      doc
+      (doc-apply-all (doc-apply doc (first ops)) (rest ops)))))
+
+;; ── render-agnostic snapshot: list of (id . type) for assertions/debug ──
+(define doc-ids (fn (doc) (map (fn (b) (blk-id b)) (doc-blocks doc))))
+
+(define
+  doc-types
+  (fn (doc) (map (fn (b) (blk-type b)) (doc-blocks doc))))