Answer for shop copiers before the player pays

A purchase always lands in the rightmost slot (buy_from_shop emplaces at
the end, button_callbacks.lua:2279), which the two copiers experience in
opposite ways: a bought Blueprint arrives copying nothing, a bought
Brainstorm copies the leftmost joker immediately. The buy-area tooltip
now says which, by name — JCA.copy_source_if_bought resolves the arrival
target (chaining through a leftmost copier exactly like copy_source),
and Blueprint's line names the joker to slot it against after buying.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

main.lua

@@ -220,6 +220,30 @@ function JCA.copy_source(card)
     return nil, 'none', chain
 end
 
+-- What a copier still IN THE SHOP would copy if bought right now. A purchase
+-- always lands in the RIGHTMOST slot (buy_from_shop hands the card to
+-- G.jokers:emplace, button_callbacks.lua:2279, and emplace appends,
+-- cardarea.lua:53) -- so a bought Blueprint arrives with no right-hand
+-- neighbour and copies nothing until the player reorders, while a bought
+-- Brainstorm reads the leftmost joker the moment it lands. Same returns as
+-- copy_source; a leftmost joker that is itself a copier is followed through
+-- copy_source so the chain resolves to the joker actually copied.
+function JCA.copy_source_if_bought(key)
+    if not (COPIERS[key] and G.jokers and G.jokers.cards) then return nil, 'none', {} end
+    if COPIERS[key] == 'right' then return nil, 'none', {} end
+    local target = G.jokers.cards[1]
+    local center = target and target.config and target.config.center
+    if not center then return nil, 'none', {} end
+    if COPIERS[center.key] then
+        local final, status, chain = JCA.copy_source(target)
+        table.insert(chain, 1, target)
+        return final, status, chain
+    end
+    if not center.blueprint_compat then return target, 'incompatible', {} end
+    if target.debuff then return target, 'debuffed', {} end
+    return target, 'ok', {}
+end
+
 -- Ceremonial Dagger is positional too, and it is the dangerous one: when the
 -- blind is selected it DESTROYS the joker to its right and eats twice its sell
 -- value as Mult (card.lua:2945). The card text says so; what it cannot tell you
@@ -633,6 +657,42 @@ local function tooltip_rows(card)
     local caution = in_buy_area(card) and JCA.cautions[key]
     if caution then text_row('Caution: ' .. caution, G.C.RED) end
 
+    -- Copiers in the shop: a purchase always lands rightmost (see
+    -- copy_source_if_bought), so say what THIS board hands the copier the
+    -- moment it arrives -- by name, before the player pays. Explanations,
+    -- not verdicts, so learning mode keeps them.
+    if in_buy_area(card) and COPIERS[key] then
+        if key == 'j_blueprint' then
+            -- The caution above already says a rightmost Blueprint is dead;
+            -- add the one thing it cannot know: which joker to slot it against.
+            local best = JCA.best_copy_target(card)
+            if best then
+                text_row('Fix after buying: slot it just left of '
+                    .. name_of(best.config.center.key), G.C.GREEN)
+            end
+        else
+            local target, status, chain = JCA.copy_source_if_bought(key)
+            local via = ''
+            for _, link in ipairs(chain) do
+                via = via .. name_of(link.config.center.key) .. ' -> '
+            end
+            local tname = target and name_of(target.config.center.key)
+            if status == 'ok' then
+                text_row('Will copy ' .. via .. tname .. ' as soon as it lands', G.C.GREEN)
+            elseif status == 'incompatible' then
+                text_row('Will copy ' .. via .. tname .. ' - which cannot be copied', G.C.RED)
+            elseif status == 'debuffed' then
+                text_row('Will copy ' .. via .. tname .. ' - debuffed, so nothing', G.C.RED)
+            else
+                local best = JCA.best_copy_target(card)
+                text_row(best
+                    and ('Will copy nothing - make ' .. name_of(best.config.center.key)
+                        .. ' your leftmost joker first')
+                    or 'Will copy nothing - no copyable joker on your board', G.C.RED)
+            end
+        end
+    end
+
     -- Run context: this deck, these hand levels. Facts that frame the tags,
     -- never part of the score; capped at two lines so multi-suit jokers do
     -- not flood the tooltip. Fixed iteration order keeps hovers stable.