Merge branch 'robustness-and-hackability'

An audit of the shipped program, plus the fixes it found.

The citation parser accepted OCaml integer-literal syntax, so a typo like
'Luke 1_1:5' silently became a different chapter. Four pairs of different
books shared a full title -- 1 and 2 Corinthians both rendered 'Epistola
ad Corinthios' -- leaving 108 citations in 2027 alone that a reader could
not resolve to a book. Spec section 8.5 is now delivered rather than
recorded: shipped styles re-parse their own output. Overlay errors no
longer name OCaml source files at the reader.

Also: the new-overlay scaffold shows citations at the right nesting
level, config --show validates before printing, error messages no longer
echo whole file lines, and a month answers to both spellings of its own
name.

2 files changed, 119 insertions, 51 deletions

diff --git a/lib/citation/book.ml b/lib/citation/book.ml
index 2a2b9c0..986a898 100644
--- a/lib/citation/book.ml
+++ b/lib/citation/book.ml
@@ -12,57 +12,57 @@ let to_string t = t
    the lectionary and was the source of every token missed in the first
    pass. *)
 let table =
-  [ ("genesis",          [ "Gen" ]);
-    ("exodus",           [ "Ex"; "Exod" ]);
-    ("leviticus",        [ "Lev" ]);
-    ("numbers",          [ "Num" ]);
-    ("kings_3",          [ "3 Kings"; "3 Kgs." ]);
-    ("kings_4",          [ "4 Kings" ]);
-    ("esdras_2",         [ "2 Esd." ]);
-    ("tobit",            [ "Tob" ]);
-    ("judith",           [ "Judith" ]);
-    ("esther",           [ "Esther" ]);
-    ("proverbs",         [ "Prov" ]);
-    ("song_of_songs",    [ "Song" ]);
-    ("wisdom",           [ "Wis"; "Wis." ]);
-    ("ecclesiasticus",   [ "Ecclus"; "Sir"; "Eccli" ]);
-    ("isaiah",           [ "Isa"; "Isa." ]);
-    ("jeremiah",         [ "Jer" ]);
-    ("ezekiel",          [ "Ezech"; "Ezek" ]);
-    ("daniel",           [ "Dan" ]);
-    ("osee",             [ "Osee" ]);
-    ("joel",             [ "Joel" ]);
-    ("jonas",            [ "Jonas" ]);
-    ("malachi",          [ "Mal" ]);
-    ("matthew",          [ "Matt"; "Matt." ]);
-    ("mark",             [ "Mark" ]);
-    ("luke",             [ "Luke" ]);
-    ("john",             [ "John" ]);
-    ("acts",             [ "Acts" ]);
-    ("romans",           [ "Rom" ]);
-    ("corinthians_1",    [ "1 Cor"; "1 Cor." ]);
-    ("corinthians_2",    [ "2 Cor"; "2 Cor." ]);
-    ("galatians",        [ "Gal" ]);
-    ("ephesians",        [ "Eph"; "Eph." ]);
-    ("philippians",      [ "Phil" ]);
-    ("colossians",       [ "Col"; "Col." ]);
-    ("thessalonians_1",  [ "1 Thess"; "1 Thess." ]);
-    ("thessalonians_2",  [ "2 Thess" ]);
-    ("timothy_1",        [ "1 Tim." ]);
-    ("timothy_2",        [ "2 Tim"; "2 Tim." ]);
-    ("titus",            [ "Titus" ]);
-    ("hebrews",          [ "Heb" ]);
-    ("james",            [ "Jas"; "James" ]);
-    ("peter_1",          [ "1 Pet"; "1 Pet." ]);
-    ("peter_2",          [ "2 Pet." ]);
-    ("john_1",           [ "1 John" ]);
+  [ ("genesis",             [ "Gen"; "Liber Genesis"; "Genesis" ]);
+    ("exodus",              [ "Ex"; "Exod"; "Liber Exodi"; "Exodus" ]);
+    ("leviticus",           [ "Lev"; "Levit"; "Liber Levitici"; "Leviticus" ]);
+    ("numbers",             [ "Num"; "Liber Numeri"; "Numbers" ]);
+    ("kings_3",             [ "3 Kings"; "3 Kgs."; "3 Reg"; "Liber Regum III" ]);
+    ("kings_4",             [ "4 Kings"; "4 Reg"; "Liber Regum IV"; "4 Kgs." ]);
+    ("esdras_2",            [ "2 Esd."; "2 Esdr"; "Liber Esdrae"; "2 Esdras" ]);
+    ("tobit",               [ "Tob"; "Liber Tobiae"; "Tobias" ]);
+    ("judith",              [ "Judith"; "Iudith"; "Liber Iudith"; "Jth" ]);
+    ("esther",              [ "Esther"; "Esth"; "Liber Esther" ]);
+    ("proverbs",            [ "Prov"; "Proverbs" ]);
+    ("song_of_songs",       [ "Song"; "Cant."; "Canticle of Canticles" ]);
+    ("wisdom",              [ "Wis"; "Wis."; "Sap"; "Liber Sapientiae"; "Wisdom" ]);
+    ("ecclesiasticus",      [ "Ecclus"; "Sir"; "Eccli"; "Ecclesiasticus" ]);
+    ("isaiah",              [ "Isa"; "Isa."; "Isai"; "Isaias Propheta"; "Isaias" ]);
+    ("jeremiah",            [ "Jer"; "Ier"; "Ieremias Propheta"; "Jeremias" ]);
+    ("ezekiel",             [ "Ezech"; "Ezek"; "Ezechiel Propheta"; "Ezechiel" ]);
+    ("daniel",              [ "Dan"; "Daniel Propheta"; "Daniel" ]);
+    ("osee",                [ "Osee"; "Osee Propheta" ]);
+    ("joel",                [ "Joel"; "Ioel"; "Ioel Propheta" ]);
+    ("jonas",               [ "Jonas"; "Ionae"; "Ionas Propheta" ]);
+    ("malachi",             [ "Mal"; "Malach"; "Malachias Propheta"; "Malachias" ]);
+    ("matthew",             [ "Matt"; "Matt."; "Matth"; "Evangelium secundum Matthaeum"; "Matthew" ]);
+    ("mark",                [ "Mark"; "Marc"; "Evangelium secundum Marcum" ]);
+    ("luke",                [ "Luke"; "Luc"; "Evangelium secundum Lucam" ]);
+    ("john",                [ "John"; "Ioann"; "Evangelium secundum Ioannem" ]);
+    ("acts",                [ "Acts"; "Act"; "Actus Apostolorum"; "Acts of the Apostles" ]);
+    ("romans",              [ "Rom"; "Epistola ad Romanos"; "Romans" ]);
+    ("corinthians_1",       [ "1 Cor"; "1 Cor."; "Epistola I ad Corinthios"; "1 Corinthians" ]);
+    ("corinthians_2",       [ "2 Cor"; "2 Cor."; "Epistola II ad Corinthios"; "2 Corinthians" ]);
+    ("galatians",           [ "Gal"; "Epistola ad Galatas"; "Galatians" ]);
+    ("ephesians",           [ "Eph"; "Eph."; "Ephes"; "Epistola ad Ephesios"; "Ephesians" ]);
+    ("philippians",         [ "Phil"; "Epistola ad Philippenses"; "Philippians" ]);
+    ("colossians",          [ "Col"; "Col."; "Epistola ad Colossenses"; "Colossians" ]);
+    ("thessalonians_1",     [ "1 Thess"; "1 Thess."; "Epistola I ad Thessalonicenses"; "1 Thessalonians" ]);
+    ("thessalonians_2",     [ "2 Thess"; "Epistola II ad Thessalonicenses"; "2 Thessalonians" ]);
+    ("timothy_1",           [ "1 Tim."; "1 Tim"; "Epistola I ad Timotheum"; "1 Timothy" ]);
+    ("timothy_2",           [ "2 Tim"; "2 Tim."; "Epistola II ad Timotheum"; "2 Timothy" ]);
+    ("titus",               [ "Titus"; "Tit"; "Epistola ad Titum" ]);
+    ("hebrews",             [ "Heb"; "Hebr"; "Epistola ad Hebraeos"; "Hebrews" ]);
+    ("james",               [ "Jas"; "James"; "Iac"; "Epistola beati Iacobi Apostoli" ]);
+    ("peter_1",             [ "1 Pet"; "1 Pet."; "1 Petri"; "Epistola I beati Petri Apostoli"; "1 Peter" ]);
+    ("peter_2",             [ "2 Pet."; "2 Petri"; "Epistola II beati Petri Apostoli"; "2 Pet"; "2 Peter" ]);
+    ("john_1",              [ "1 John"; "1 Ioann"; "Epistola beati Ioannis Apostoli" ]);
     (* "Apoc" is the Vulgate spelling and "Rev" its modern equivalent, but
        BOTH sit inside Vulgate-tradition data, so both resolve to the same
        Vulgate id here -- see book.mli's note by [apocalypse] never being an
        [of_token] result under that name. Do not add "revelation" as a
        spelling: it exists only as a tradition target (below), and giving it
        an [of_token] entry would let one book carry two different ids. *)
-    ("apocalypse",       [ "Apoc"; "Rev" ]) ]
+    ("apocalypse",          [ "Apoc"; "Rev"; "Liber Apocalypsis"; "Apocalypse" ]) ]
 
 (* Targets a tradition can map ONTO that the Vulgate data never cites
    directly. Present so [tradition_of_fields] can validate both sides.
@@ -70,16 +70,34 @@ let table =
    "Sir" and "Rev" already resolve to the Vulgate ids [ecclesiasticus] and
    [apocalypse] above, so a modern-numbering tradition maps ONTO these
    targets rather than data ever citing them directly. *)
-let tradition_targets =
-  [ "kings_1"; "kings_2"; "nehemiah"; "sirach"; "hosea"; "jonah"; "revelation" ]
+
+(* The modern-numbering targets. They have table rows so that colitur's OWN
+   rendered output re-parses: with --sigla-tradition modern the book prints
+   as "1 Reg" or "1 Kings", and a user copying that back into an overlay must
+   get it read correctly. The shipped data never cites them directly, which
+   is why they are listed apart. *)
+let tradition_target_table =
+  [
+    ("kings_1",           [ "1 Reg"; "Liber Regum I"; "1 Kgs"; "1 Kings" ]);
+    ("kings_2",           [ "2 Reg"; "Liber Regum II"; "2 Kgs"; "2 Kings" ]);
+    ("nehemiah",          [ "Neh"; "Liber Nehemiae"; "Nehemiah" ]);
+    ("sirach",            [ "Liber Ecclesiastici"; "Sirach" ]);
+    ("hosea",             [ "Os"; "Hos"; "Hosea" ]);
+    ("jonah",             [ "Ion"; "Jon"; "Jonah" ]);
+    ("revelation",        [ "Apocalypsis"; "Revelation" ]);
+  ]
+
+let tradition_targets = List.map fst tradition_target_table
 
 let all = List.map fst table @ tradition_targets
 
 let tokens =
-  List.concat_map (fun (id, sp) -> List.map (fun s -> (s, id)) sp) table
+  List.concat_map
+    (fun (id, sp) -> List.map (fun s -> (s, id)) sp)
+    (table @ tradition_target_table)
 
 let default_spelling id =
-  match List.assoc_opt id table with
+  match List.assoc_opt id (table @ tradition_target_table) with
   | Some (first :: _) -> first
   | Some [] | None -> id
 
diff --git a/lib/citation/parse.ml b/lib/citation/parse.ml
index 45fbb72..2f2316e 100644
--- a/lib/citation/parse.ml
+++ b/lib/citation/parse.ml
@@ -9,7 +9,41 @@ let split_on c s = String.split_on_char c s |> List.map String.trim
 (* The book is the longest leading run of non-digit words, allowing one
    leading ordinal ("1 Cor", "3 Kings"). Everything after it is the
    reference tail. *)
+(* Longest REGISTERED token that prefixes [s] and is followed by a space and
+   a digit. This is what lets a MULTI-WORD title parse: the heuristic below
+   stops at the first space, so "Evangelium secundum Lucam 5:12-14" would
+   otherwise split as the book "Evangelium" and fail.
+
+   Longest-match matters and is not decoration: "Liber Regum III" and
+   "Liber Regum IV" share a prefix with each other, and a shortest-match
+   would read both as some other book entirely. *)
+let longest_token_prefix s =
+  let n = String.length s in
+  let best = ref None in
+  List.iter
+    (fun (tok, _) ->
+      let tl = String.length tok in
+      if
+        tl < n
+        && String.sub s 0 tl = tok
+        && s.[tl] = ' '
+        (* a digit must follow, or "Job" would swallow the start of a
+           different book whose name merely begins the same way *)
+        && (let j = ref (tl + 1) in
+            while !j < n && s.[!j] = ' ' do incr j done;
+            !j < n && s.[!j] >= '0' && s.[!j] <= '9')
+      then
+        match !best with
+        | Some (b, _) when String.length b >= tl -> ()
+        | _ -> best := Some (tok, String.trim (String.sub s tl (n - tl)))
+    )
+    Book.tokens;
+  !best
+
 let split_book s =
+  match longest_token_prefix s with
+  | Some (book, tail) when tail <> "" -> Some (book, tail)
+  | _ ->
   let n = String.length s in
   let i = ref 0 in
   (* optional leading ordinal digit *)
@@ -25,7 +59,21 @@ let split_book s =
     let tail = String.trim (String.sub s !i (n - !i)) in
     if book = "" || tail = "" then None else Some (book, tail)
 
-let int_opt s = int_of_string_opt (String.trim s)
+(* A citation number is PLAIN DIGITS and positive -- nothing else.
+   [int_of_string_opt] also accepts OCaml's own integer-literal syntax, so
+   "1_1" would read as 11 and "+5" as 5: a transcription typo silently
+   becoming a DIFFERENT chapter, which nothing downstream could detect. A
+   user overlay supplies arbitrary strings, so this is reachable, not
+   theoretical. Chapter and verse numbering both start at 1, so zero is
+   rejected too. *)
+let int_opt s =
+  let s = String.trim s in
+  let ok =
+    s <> ""
+    && String.for_all (function '0' .. '9' -> true | _ -> false) s
+  in
+  if not ok then None
+  else match int_of_string_opt s with Some n when n > 0 -> Some n | _ -> None
 
 (* "20-32" -> {first=20; last=Some 32};  "21" -> {first=21; last=None} *)
 let parse_range s =
@@ -33,7 +81,9 @@ let parse_range s =
   | [ a ] -> ( match int_opt a with Some f -> Some { first = f; last = None } | None -> None)
   | [ a; b ] -> (
       match (int_opt a, int_opt b) with
-      | Some f, Some l -> Some { first = f; last = Some l }
+      (* A descending range ("1:20-10") is always a transcription error;
+         accepting it would render back out as a citation nobody can follow. *)
+      | Some f, Some l when l >= f -> Some { first = f; last = Some l }
       | _ -> None)
   | _ -> None