From 0fda99f93b19617f749aaf42a4ff9255bd4febf1 Mon Sep 17 00:00:00 2001
From: Karl Ostmo <kostmo@gmail.com>
Date: Mon, 14 Oct 2024 16:12:25 -0700
Subject: [PATCH] DNA copying challenge (#1031)

A challenge that utilizes a stack.
Closes #932.

Demo:
```
scripts/play.sh --scenario data/scenarios/Challenges/dna.yaml --autoplay
```
![Screenshot from 2024-10-13 17-06-06](https://github.com/user-attachments/assets/678984b0-f83d-4e0d-8958-dfcd33461ce6)
---
 data/scenarios/Challenges/00-ORDER.txt       |   1 +
 data/scenarios/Challenges/_dna/lab.sw        | 177 ++++++
 data/scenarios/Challenges/_dna/mirrorbot.sw  |  99 ++++
 data/scenarios/Challenges/_dna/resetter.sw   |  48 ++
 data/scenarios/Challenges/_dna/solution.sw   | 262 ++++++++
 data/scenarios/Challenges/_dna/topchecker.sw | 107 ++++
 data/scenarios/Challenges/dna.yaml           | 593 +++++++++++++++++++
 test/integration/Main.hs                     |   1 +
 8 files changed, 1288 insertions(+)
 create mode 100644 data/scenarios/Challenges/_dna/lab.sw
 create mode 100644 data/scenarios/Challenges/_dna/mirrorbot.sw
 create mode 100644 data/scenarios/Challenges/_dna/resetter.sw
 create mode 100644 data/scenarios/Challenges/_dna/solution.sw
 create mode 100644 data/scenarios/Challenges/_dna/topchecker.sw
 create mode 100644 data/scenarios/Challenges/dna.yaml

diff --git a/data/scenarios/Challenges/00-ORDER.txt b/data/scenarios/Challenges/00-ORDER.txt
index eb26f5eec..c1c1f6c3b 100644
--- a/data/scenarios/Challenges/00-ORDER.txt
+++ b/data/scenarios/Challenges/00-ORDER.txt
@@ -16,6 +16,7 @@ wave.yaml
 gallery.yaml
 wolf-goat-cabbage.yaml
 blender.yaml
+dna.yaml
 friend.yaml
 pack-tetrominoes.yaml
 dimsum.yaml
diff --git a/data/scenarios/Challenges/_dna/lab.sw b/data/scenarios/Challenges/_dna/lab.sw
new file mode 100644
index 000000000..6e7aa2d6b
--- /dev/null
+++ b/data/scenarios/Challenges/_dna/lab.sw
@@ -0,0 +1,177 @@
+def doN = \n. \f. if (n > 0) {f; doN (n - 1) f} {}; end;
+
+def getBaseForNumber = \n.
+    if (n == 0) {
+        "guanine";
+    } {
+        if (n == 1) {
+            "cytosine";
+        } {
+            if (n == 2) {
+                "adenine";
+            } {
+                "thymine";
+            };
+        };
+    };
+    end;
+
+def getNumberForBase = \n.
+    if (n == "guanine") {
+        0;
+    } {
+        if (n == "cytosine") {
+            1;
+        } {
+            if (n == "adenine") {
+                2;
+            } {
+                3;
+            };
+        };
+    };
+    end;
+
+/** Toggle the lowest bit */
+def getComplementNumber = \n.
+    if (n == 0) {
+        1;
+    } {
+        if (n == 1) {
+            0;
+        } {
+            if (n == 2) {
+                3;
+            } {
+                2;
+            };
+        };
+    };
+    end;
+
+def waitUntilSomethingExists =
+    maybeItemHere <- scan down;
+    case maybeItemHere (\_. 
+        watch down;
+        wait 1000;
+        waitUntilSomethingExists;
+    ) return;
+    end;
+
+def waitUntilHere = \item.
+    hereNow <- ishere item;
+    if hereNow {} {
+        watch down;
+        wait 1000;
+        waitUntilHere item;
+    };
+    end;
+
+def waitUntilOccupied =
+    stillEmpty <- isempty;
+    if stillEmpty {
+        watch down;
+        wait 1000;
+        waitUntilOccupied;
+    } {};
+    end;
+
+def myStandby = \receptacleLoc.
+    teleport self receptacleLoc;
+    entToClone <- grab;
+    teleport self (36, -11);
+    turn back;
+    return $ inR entToClone;
+    end;
+
+def placeBase = \standbyFunc. \n. 
+
+    if (n > 0) {
+        idx <- random 4;
+        let entTemp = getBaseForNumber idx in
+        let ent = entTemp in
+        create ent;
+        place ent;
+        move;
+
+        clonedOrganism <- placeBase standbyFunc $ n - 1;
+
+        // Unwinds the stack; verifies the original placement order
+        placedEnt <- instant waitUntilSomethingExists;
+        let isGood = ent == placedEnt in
+        move;
+
+        if isGood {
+            return clonedOrganism;
+        } {
+            return $ inL ();
+        }
+    } {
+        // Returns the clonedOrganism
+        standbyFunc;
+    };
+    end;
+
+def makeDnaStrand = \receptacleLoc.
+    teleport self (5, -2);
+
+    dims <- floorplan "DNA decoder";
+    let decoderWidth = fst dims in
+    eitherClonedOrganism <- placeBase (myStandby receptacleLoc) decoderWidth;
+
+    case eitherClonedOrganism (\_.
+        create "pixel (R)";
+    ) (\clonedItem.
+        instant $ (
+            teleport self (0, -11);
+            waitUntilHere "switch (on)";
+
+            bottomWaypointQuery <- waypoint "receiver" 1;
+            let receptacleLoc2 = snd bottomWaypointQuery in
+            teleport self receptacleLoc2;
+
+            sow clonedItem;
+            create clonedItem;
+            k <- robotnamed "keeper";
+            give k clonedItem;
+
+            let slideBox = "slide box" in
+            create slideBox;
+            give base slideBox;
+            say $ "You got a new \"" ++ slideBox ++ "\"";
+        );
+    );
+    end;
+
+def waitForCloneableOrganism =
+
+    waypointQuery <- waypoint "receiver" 0;
+    let receptacleLoc = snd waypointQuery in
+    organism <- instant (
+        teleport self receptacleLoc;
+
+        waitUntilOccupied;
+
+        thingHere <- scan down;
+        case thingHere (\x. return $ inL x) (\item.
+            isOrganism <- hastag item "organism";
+            return $ inR item;
+        );
+    );
+
+    case organism (\_.
+        say "Not a cloneable organism!";
+        waitForCloneableOrganism;
+    ) (\item.
+        create "pixel (G)";
+        makeDnaStrand receptacleLoc;
+    );
+    end;
+
+def go =
+    waitForCloneableOrganism;
+    turn east;
+    go;
+    end;
+
+go;
diff --git a/data/scenarios/Challenges/_dna/mirrorbot.sw b/data/scenarios/Challenges/_dna/mirrorbot.sw
new file mode 100644
index 000000000..c9ce6abef
--- /dev/null
+++ b/data/scenarios/Challenges/_dna/mirrorbot.sw
@@ -0,0 +1,99 @@
+def doN = \n. \f. if (n > 0) {f; doN (n - 1) f} {}; end;
+
+def getBaseForNumber = \n.
+    if (n == 0) {
+        "guanine";
+    } {
+        if (n == 1) {
+            "cytosine";
+        } {
+            if (n == 2) {
+                "adenine";
+            } {
+                "thymine";
+            };
+        };
+    };
+    end;
+
+def getNumberForBase = \n.
+    if (n == "guanine") {
+        0;
+    } {
+        if (n == "cytosine") {
+            1;
+        } {
+            if (n == "adenine") {
+                2;
+            } {
+                if (n == "thymine") {
+                    3;
+                } {-1};
+            };
+        };
+    };
+    end;
+
+/** Toggle the lowest bit */
+def getComplementNumber = \n.
+    if (n == 0) {
+        1;
+    } {
+        if (n == 1) {
+            0;
+        } {
+            if (n == 2) {
+                3;
+            } {
+                2;
+            };
+        };
+    };
+    end;
+
+def placeComplementOf = \item.
+    let baseNumber = getNumberForBase item in
+    if (baseNumber >= 0) {
+        let complementNumber = getComplementNumber baseNumber in
+        let newItem = getBaseForNumber complementNumber in
+        move;
+        create newItem;
+        place newItem;
+    } {
+        let sludge = "organic sludge" in
+        create sludge;
+        place sludge;
+    }
+    end;
+
+def waitUntilHere =
+    watch down;
+    wait 1000;
+
+    maybeItemDown <- scan down;
+    case maybeItemDown (\_. waitUntilHere) (\itemHere.
+        placeComplementOf itemHere;
+    );
+    end;
+
+def waitUntilEmpty =
+    watch down;
+    wait 1000;
+    emptyHere <- isempty;
+    if emptyHere {
+        // reset the position
+        turn back;
+        move;
+        turn back;
+    } {
+        waitUntilEmpty;
+    }
+    end;
+
+def go =
+    instant waitUntilHere;
+    waitUntilEmpty;
+    go;
+    end;
+
+go;
diff --git a/data/scenarios/Challenges/_dna/resetter.sw b/data/scenarios/Challenges/_dna/resetter.sw
new file mode 100644
index 000000000..a88379175
--- /dev/null
+++ b/data/scenarios/Challenges/_dna/resetter.sw
@@ -0,0 +1,48 @@
+def doN = \n. \f. if (n > 0) {f; doN (n - 1) f} {}; end;
+
+/**
+Assumes we are on the left edge of a row of nucleobases
+*/
+def resetPlayfieldRow =
+    dims <- floorplan "DNA decoder";
+    let decoderWidth = fst dims in
+    doN decoderWidth (grab; move;);
+    end;
+
+def resetPlayfield =
+    teleport self (5, -2);
+    resetPlayfieldRow;
+    teleport self (5, -3);
+    resetPlayfieldRow;
+
+    teleport self (5, -11);
+    resetPlayfieldRow;
+    teleport self (5, -12);
+    resetPlayfieldRow;
+    end;
+
+def watchSwitch = \lastState.
+    watch down;
+    wait 1000;
+    found <- scan down;
+    case found return (\item.
+        if (item != lastState) {
+            if (item == "switch (off)") {
+                loc <- whereami;
+                resetPlayfield;
+                teleport self loc;
+            } {
+            };
+        } {};
+        watchSwitch item;
+    );
+    end;
+
+def go =
+    instant $ (
+        found <- scan down;
+        case found return watchSwitch;
+    );
+    end;
+
+go;
diff --git a/data/scenarios/Challenges/_dna/solution.sw b/data/scenarios/Challenges/_dna/solution.sw
new file mode 100644
index 000000000..d63f598b3
--- /dev/null
+++ b/data/scenarios/Challenges/_dna/solution.sw
@@ -0,0 +1,262 @@
+def doN = \n. \f. if (n > 0) {f; doN (n - 1) f} {}; end;
+
+def moveUntilBlocked =
+    blockedHere <- blocked;
+    if blockedHere {} {
+        move;
+        moveUntilBlocked;
+    }
+    end;
+
+def getBaseForNumber = \n.
+    if (n == 0) {
+        "guanine";
+    } {
+        if (n == 1) {
+            "cytosine";
+        } {
+            if (n == 2) {
+                "adenine";
+            } {
+                "thymine";
+            };
+        };
+    };
+    end;
+
+def getNumberForBase = \n.
+    if (n == "guanine") {
+        0;
+    } {
+        if (n == "cytosine") {
+            1;
+        } {
+            if (n == "adenine") {
+                2;
+            } {
+                3;
+            };
+        };
+    };
+    end;
+
+/** Toggle the lowest bit */
+def getComplementNumber = \n.
+    if (n == 0) {
+        1;
+    } {
+        if (n == 1) {
+            0;
+        } {
+            if (n == 2) {
+                3;
+            } {
+                2;
+            };
+        };
+    };
+    end;
+
+def waitWhileHere = \item.
+    stillHere <- ishere item;
+    if stillHere {
+        watch down;
+        wait 1000;
+        waitWhileHere item;
+    } {};
+    end;
+
+def waitUntilHere = \item.
+    hereNow <- ishere item;
+    if hereNow {} {
+        watch down;
+        wait 1000;
+        waitUntilHere item;
+    };
+    end;
+
+def moveToPattern =
+    turn back;
+    doN 5 move;
+    turn left;
+    doN 4 move;
+    turn left;
+    move;
+    end;
+
+def moveToOtherRow =
+    turn right;
+    doN 2 move;
+    turn right;
+    doN 4 move;
+    turn left;
+    doN 4 move;
+    turn left;
+    doN 4 move;
+    turn right;
+    doN 2 move;
+    turn right;
+    move;
+    end;
+
+def waitForItem : Dir -> Cmd Text = \d.
+    item <- scan d;
+    case item (\_. 
+        watch d;
+        wait 1000;
+        waitForItem d;
+    ) return;
+    end;
+
+def waitForSpecificItem = \item. \d.
+    itemIsHere <- ishere item;
+    if itemIsHere {
+    } {
+        watch d;
+        wait 1000;
+        waitForSpecificItem item d;
+    }
+    end;
+
+def placeComplementOf = \item.
+    let baseNumber = getNumberForBase item in
+    let complementNumber = getComplementNumber baseNumber in
+    let newItem = getBaseForNumber complementNumber in
+    place newItem;
+    end;
+
+/**
+Store the observed entities in the recursion stack.
+*/
+def replicatePattern = \standbyFunc. \n.
+    if (n > 0) {
+        thingTemp <- waitForItem left;
+        let thing = thingTemp in
+        placeComplementOf thing;
+        move;
+        replicatePattern standbyFunc $ n - 1;
+
+        place thing;
+        move;
+    } {
+        standbyFunc;
+    }
+    end;
+
+/**
+Position self at entrance
+*/
+def pickFlowerAndWater =
+    doN 6 move;
+    dahlia <- grab;
+
+    turn left;
+    doN 8 move;
+    turn right;
+    doN 31 move;
+    clover <- grab;
+    turn back;
+    doN 35 move;
+    d <- grab;
+    doN 10 move;
+
+    turn left;
+
+    doN 18 move;
+    use "siphon" forward;
+    turn left;
+    doN 7 (
+        move;
+        use "siphon" right;
+    );
+    doN 4 move;
+    turn right;
+    doN 16 move;
+
+    mushroom <- grab;
+
+    turn back;
+    doN 23 move;
+    
+    turn right;
+    return dahlia;
+    
+    // return mushroom;
+    // return d;
+    end;
+
+
+def waitUntilOccupied =
+    stillEmpty <- isempty;
+    if stillEmpty {
+        watch down;
+        wait 1000;
+        waitUntilOccupied;
+    } {};
+    end;
+
+def returnToInputReceptacle =
+    turn back;
+    doN 5 move;
+    turn left;
+    moveUntilBlocked;
+    turn left;
+    doN 29 move;
+    turn right;
+    moveUntilBlocked;
+    turn left;
+    doN 4 move;
+    turn right;
+    doN 6 move;
+    turn right;
+    moveUntilBlocked;
+    end;
+
+def completeDnaTask = \sentinel.
+    place sentinel;
+    make "specimen slide";
+
+    doN 16 $ make "cytosine";
+
+    waitWhileHere sentinel;
+    moveToPattern;
+    replicatePattern moveToOtherRow 32;
+    
+    // Activate the switch
+    doN 3 move;
+    drill forward;
+    wait 2;
+    drill forward;
+
+    turn left;
+    doN 6 move;
+    turn left;
+    doN 32 move;
+    turn left;
+    doN 2 move;
+    turn left;
+    move;
+
+    waitUntilOccupied;
+    grab;
+
+    returnToInputReceptacle;
+    end;
+
+def iterateOrganisms = \idx.
+    result <- tagmembers "organism" idx;
+    let totalCount = fst result in
+    if (idx < totalCount) {
+        completeDnaTask $ snd result;
+        iterateOrganisms $ idx + 1;
+    } {};
+    end;
+
+def go =
+    _sentinel <- pickFlowerAndWater;
+    moveUntilBlocked;
+
+    iterateOrganisms 0;
+    end;
+
+go;
diff --git a/data/scenarios/Challenges/_dna/topchecker.sw b/data/scenarios/Challenges/_dna/topchecker.sw
new file mode 100644
index 000000000..abb4b63da
--- /dev/null
+++ b/data/scenarios/Challenges/_dna/topchecker.sw
@@ -0,0 +1,107 @@
+def doN = \n. \f. if (n > 0) {f; doN (n - 1) f} {}; end;
+
+def getBaseForNumber = \n.
+    if (n == 0) {
+        "guanine";
+    } {
+        if (n == 1) {
+            "cytosine";
+        } {
+            if (n == 2) {
+                "adenine";
+            } {
+                "thymine";
+            };
+        };
+    };
+    end;
+
+def getNumberForBase = \n.
+    if (n == "guanine") {
+        0;
+    } {
+        if (n == "cytosine") {
+            1;
+        } {
+            if (n == "adenine") {
+                2;
+            } {
+                if (n == "thymine") {
+                    3;
+                } {-1};
+            };
+        };
+    };
+    end;
+
+/** Toggle the lowest bit */
+def getComplementNumber = \n.
+    if (n == 0) {
+        1;
+    } {
+        if (n == 1) {
+            0;
+        } {
+            if (n == 2) {
+                3;
+            } {
+                2;
+            };
+        };
+    };
+    end;
+
+def waitUntilHere = \remainingCount.
+    if (remainingCount > 0) {
+        maybeItemHere <- scan down;
+        case maybeItemHere (\_. 
+            watch down;
+            wait 1000;
+            waitUntilHere remainingCount;
+        ) (\itemHere.
+
+            maybeItemAbove <- scan left;
+            case maybeItemAbove (\_. fail "Expected an item here.") (\itemAbove.
+                let num = getNumberForBase itemAbove in
+                if (num >= 0) {
+                    let complementNum = getComplementNumber num in
+                    let complementItem = getBaseForNumber complementNum in
+                    if (complementItem == itemHere) {
+                        move;
+                        waitUntilHere $ remainingCount - 1;
+                    } {
+                        create "pixel (R)";
+                    }
+                } {
+                    fail "Expected nonnegative item index."
+                }
+            );
+        );
+    } {
+        create "pixel (G)";
+    };
+    end;
+
+def waitUntilEmpty =
+    watch down;
+    wait 1000;
+    emptyHere <- isempty;
+    if emptyHere {} {
+        waitUntilEmpty;
+    }
+    end;
+
+def waitForReset =
+    backup;
+    waitUntilEmpty;
+    end;
+
+def go = \startingLoc.
+    instant $ waitUntilHere 32;
+    waitForReset;
+    teleport self startingLoc;
+    go startingLoc;
+    end;
+
+loc <- whereami;
+go loc;
diff --git a/data/scenarios/Challenges/dna.yaml b/data/scenarios/Challenges/dna.yaml
new file mode 100644
index 000000000..369510ff4
--- /dev/null
+++ b/data/scenarios/Challenges/dna.yaml
@@ -0,0 +1,593 @@
+version: 1
+name: DNA
+author: Karl Ostmo
+description: |
+  Copy strands of DNA in the lab to replicate organisms
+creative: false
+seed: 9
+attrs:
+  - name: floorattr
+    bg: "#111111"
+  - name: wall2
+    fg: "#88ee22"
+  - name: pink
+    fg: "#ff99bb"
+  - name: lemon
+    fg: "#eeee99"
+  - name: clover
+    bg: "#225522"
+  - name: beige
+    fg: "#f5f5dc"
+  - name: soup
+    fg: "#338822"
+    bg: "#774422"
+terrains:
+  - name: floor
+    attr: floorattr
+    description: |
+      Laboratory floor
+objectives:
+  - id: place_flower
+    teaser: Place subject
+    goal:
+      - |
+        The laboratory building ahead is neatly landscaped, though
+        its decorative `pond`{=structure} exudes a peculiar quality.
+        There may be a device you can `use` to sample its contents.
+
+        The DNA lab has two large apparatus inside.
+        The first is a `DNA sequencer`{=structure} that
+        determines the arrangement of ATCG pairs within an `organism`{=tag}'s genome.
+
+        The `DNA decoder`{=structure} in the lab's south wing can reconstitute
+        an `organism`{=tag} from its genome.
+
+        To get started, borrow a `dahlia`{=entity} from the flowerbed at the lab
+        entrance and place it in the receptacle directly to your east.
+    condition: |
+      r <- robotnamed "lab";
+      as r {
+        has "pixel (G)";
+      }
+  - id: place_complements
+    teaser: Complement strand
+    prerequisite: place_flower
+    goal:
+      - |
+        The `DNA sequencer`{=structure} will begin to decode the subject's DNA.
+        The subject will be dematerialized once the top row
+        of the "double helix" has been decoded.
+
+        You must then complete the double helix (fill in the second row within the device)
+        with complementary base pairs.
+        Use your `soup strainer`{=entity} to obtain ingredients.
+        Consult your *Compendium* for appropriate pairings.
+
+        Note that `scan`ning has a cost, and you have a limited supply of
+        `specimen slide`{=entity}s (in a `slide box`{=entity}) with which to
+        `scan` DNA bases using your `microscope`{=entity}.
+    condition: |
+      r <- robotnamed "topchecker";
+      as r {
+        has "pixel (G)";
+      }
+  - id: create_clone
+    prerequisite: place_complements
+    teaser: Create clone
+    goal:
+      - |
+        Now let's make a clone! Recreate the top half of the
+        DNA strand in the south wing's `DNA decoder`{=structure}
+        (you remember the sequence, right?).
+
+        Each element you `place` will be automatically complemented.
+
+        When all segments are placed, `drill` the switch on the western wall to
+        commence rematerialization. `grab` the clone (once matured) as a souvenir!
+    condition: |
+      def checkMember = \idx.
+        result <- tagmembers "organism" idx;
+        let totalCount = fst result in
+        hasThis <- has $ snd result;
+        if hasThis {
+          return true;
+        } {
+          if (idx < totalCount - 1) {
+            checkMember $ idx + 1;
+          } {
+            return false;
+          }
+        };
+        end;
+
+      k <- robotnamed "keeper";
+      as k {
+        checkMember 0;
+      }
+  - prerequisite: create_clone
+    teaser: More clones
+    goal:
+      - |
+        Toggle the switch off to reset the lab.
+      - |
+        Find three more different `organism`{=tag}s to clone.
+        Explore outside nearby the lab for specimens.
+    condition: |
+      def countMembers = \memberCount. \idx.
+        result <- tagmembers "organism" idx;
+        let totalCount = fst result in
+
+        if (idx < totalCount) {
+          hasThis <- has $ snd result;
+          let memberCountAddition = if hasThis {1} {0} in
+          countMembers (memberCount + memberCountAddition) $ idx + 1;
+        } {
+          return memberCount;
+        }
+        end;
+
+      k <- robotnamed "keeper";
+      as k {
+        c <- countMembers 0 0;
+        return $ c >= 4;
+      }
+robots:
+  - name: base
+    dir: east
+    loc: [-8, 4]
+    devices:
+      - antenna
+      - ADT calculator
+      - barcode reader
+      - branch predictor
+      - comparator
+      - compass
+      - dictionary
+      - feeler
+      - grabber
+      - hearing aid
+      - lambda
+      - logger
+      - microscope
+      - rolex
+      - siphon
+      - soup strainer
+      - strange loop
+      - switch puller
+      - treads
+      - welder
+      - workbench
+    inventory:
+      - [1, slide box]
+  - name: lab
+    system: true
+    dir: east
+    display:
+      invisible: true
+      attr: 'robot'
+    devices:
+      - switch puller
+    inventory:
+      - [1, branch predictor]
+      - [1, treads]
+      - [1, beaglepuss]
+      - [1, antenna]
+      - [1, comparator]
+      - [1, clock]
+      - [1, workbench]
+      - [1, grabber]
+      - [1, ADT calculator]
+      - [1, dictionary]
+      - [1, lambda]
+      - [1, logger]
+      - [1, welder]
+      - [1, hearing aid]
+      - [1, scanner]
+      - [1, strange loop]
+      - [1, solar panel]
+    program: |
+      run "data/scenarios/Challenges/_dna/lab.sw"
+  - name: topchecker
+    system: true
+    dir: east
+    display:
+      invisible: true
+      attr: 'robot'
+    program: |
+      run "data/scenarios/Challenges/_dna/topchecker.sw"
+  - name: mirrorbot
+    system: true
+    dir: south
+    display:
+      invisible: true
+      attr: 'robot'
+    program: |
+      run "data/scenarios/Challenges/_dna/mirrorbot.sw"
+  - name: resetter
+    description: resets the apparatus after completion by watching the switch
+    system: true
+    dir: east
+    display:
+      invisible: true
+      attr: 'robot'
+    program: |
+      run "data/scenarios/Challenges/_dna/resetter.sw"
+  - name: keeper
+    description: keeps track of cloned specimens
+    system: true
+    dir: south
+    display:
+      invisible: true
+      attr: 'robot'
+solution: |
+  run "data/scenarios/Challenges/_dna/solution.sw"
+structures:
+  - name: pond
+    recognize:
+      - north
+    structure:
+      mask: '.'
+      palette:
+        'x': [grass, rock]
+        'w': [dirt, pond broth]
+      map: |
+        ...xxxxxxxx..
+        ..xwwwwwwwwx.
+        ..xwwwwwwwwwx
+        ..xwwwwwwwwwx
+        .xwwwwwwxxxx.
+        xwwwwwwx.....
+        xwwwwwwx.....
+        .xxxxxx......
+  - name: fairy ring
+    structure:
+      mask: '.'
+      palette:
+        'm': [grass, mushroom]
+      map: |
+        ....mm.m...
+        ..m........
+        .........m.
+        ..m........
+        ...m...m...
+  - name: receptacle
+    structure:
+      mask: '.'
+      palette:
+        'x': [floor, wall]
+        'w': [floor, wall2]
+        'f':
+          cell: [floor, erase]
+          waypoint:
+            name: receiver
+      map: |
+        ww........
+        fwxxxxxxxx
+        ww.x.x.x.x
+  - name: decoder base
+    structure:
+      palette:
+        '┬': [stone, down and horizontal wall]
+        '┴': [stone, up and horizontal wall]
+        ':': [floor, erase]
+      map: |
+        ┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬
+        ::::::::::::::::::::::::::::::::
+        ::::::::::::::::::::::::::::::::
+        ┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴
+  - name: copybots overlay
+    structure:
+      mask: '.'
+      palette:
+        'm': [floor, erase, mirrorbot]
+      map: |
+        ................................
+        mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm
+        ................................
+        ................................
+  - name: decoder overlay
+    structure:
+      mask: '.'
+      palette:
+        'c': [floor, erase, topchecker]
+      map: |
+        ................................
+        ................................
+        c...............................
+        ................................
+  - name: DNA decoder
+    recognize:
+      - north
+    structure:
+      placements:
+        - src: decoder base
+        - src: copybots overlay
+        - src: receptacle
+          offset: [18, -4]
+          orient:
+            up: south
+      map: ""
+  - name: DNA sequencer
+    recognize:
+      - north
+    structure:
+      placements:
+        - src: decoder base
+        - src: decoder overlay
+        - src: receptacle
+          offset: [4, 3]
+      map: ""
+entities:
+  - name: barcode reader
+    display:
+      attr: red
+      char: 'S'
+    description:
+      - Reads the 'tag' of an item
+    properties: [pickable]
+    capabilities: [hastag, tagmembers]
+  - name: dahlia
+    display:
+      char: '*'
+      attr: pink
+    description:
+      - Brightly colored flower
+    properties: [known, pickable, growable]
+    growth:
+      duration: [20, 30]
+    tags: [organism]
+  - name: daisy
+    display:
+      char: 'x'
+      attr: lemon
+    description:
+      - Pretty flower
+    properties: [pickable, growable]
+    growth:
+      duration: [15, 30]
+    tags: [organism]
+  - name: clover
+    display:
+      char: 'c'
+      attr: clover
+    description:
+      - A tiny, 3-leaf plant
+    properties: [pickable, growable]
+    growth:
+      duration: [10, 20]
+    tags: [organism]
+  - name: mushroom
+    display:
+      char: 'm'
+      attr: beige
+    description:
+      - Invasive fungus
+    properties: [pickable, growable]
+    growth:
+      duration: [15, 25]
+      spread:
+        radius: 2
+        density: 0.5
+    biomes: [floor, stone]
+    tags: [organism]
+  - name: wall2
+    display:
+      char: 'w'
+      attr: wall2
+    description:
+      - Just a wall
+    properties: [known, unwalkable, boundary]
+  - name: primordial soup
+    display:
+      char: 's'
+      attr: soup
+    description:
+      - Can be decomposed into nucleic acids
+    properties: [pickable, liquid]
+  - name: pond broth
+    display:
+      char: 's'
+      attr: soup
+    description:
+      - Can be decomposed into nucleic acids
+    properties: [pickable, liquid]
+  - name: soup strainer
+    display:
+      char: 'r'
+    description:
+      - Extracts nucleic acids from `primordial soup`{=entity}
+    properties: [known, pickable]
+  - name: feeler
+    display:
+      char: 'm'
+    description:
+      - Senses presence of specific entities
+    properties: [known, pickable]
+    capabilities: [blocked, ishere, isempty]
+  - name: microscope
+    display:
+      char: 'm'
+    description:
+      - Scan for the cost of 1 `specimen slide`{=entity}
+    properties: [known, pickable]
+    capabilities:
+      - capability: scan
+        cost:
+          - [1, "specimen slide"]
+  - name: specimen slide
+    display:
+      char: 'i'
+      attr: device
+    description:
+      - Can take a sample of DNA for scanning
+  - name: slide box
+    display:
+      char: 'b'
+      attr: device
+    description:
+      - Contains `specimen slides`{=entity}
+  - name: guanine
+    display:
+      char: 'G'
+      attr: red
+    description:
+      - One of the four nucleobases in DNA.
+      - Is paired with `cytosine`{=entity}.
+    properties: [known]
+  - name: cytosine
+    display:
+      char: 'C'
+      attr: blue
+    description:
+      - One of the four nucleobases in DNA.
+      - Is paired with `guanine`{=entity}.
+    properties: [known]
+  - name: adenine
+    display:
+      char: 'A'
+      attr: green
+    description:
+      - One of the four nucleobases in DNA.
+      - Is paired with `thymine`{=entity}.
+    properties: [known]
+  - name: thymine
+    display:
+      char: 'T'
+      attr: gold
+    description:
+      - One of the four nucleobases in DNA.
+      - Is paired with `adenine`{=entity}.
+    properties: [known]
+  - name: switch (off)
+    display:
+      attr: red
+      char: '•'
+    description:
+      - A control in the deactivated position.
+    properties: [known]
+  - name: switch (on)
+    display:
+      attr: green
+      char: '•'
+    description:
+      - A control in the activated position.
+    properties: [known]
+  - name: organic sludge
+    display:
+      attr: green
+      char: 'S'
+    description:
+      - A repulsive, shuddering mass of slime.
+    properties: [pickable]
+  - name: switch puller
+    display:
+      char: 'P'
+      attr: gold
+    capabilities: [drill]
+    description:
+      - Can pull switches
+  - name: siphon
+    display:
+      char: 's'
+      attr: device
+    capabilities: [drill]
+    description:
+      - Can retrieve liquid
+recipes:
+  - in:
+      - [1, slide box]
+    out:
+      - [32, specimen slide]
+  - in:
+      - [1, primordial soup]
+    out:
+      - [4, cytosine]
+      - [4, guanine]
+      - [4, adenine]
+      - [4, thymine]
+    required:
+      - [1, soup strainer]
+  - in:
+      - [1, switch (off)]
+    out:
+      - [1, switch (on)]
+    required:
+      - [1, switch puller]
+  - in:
+      - [1, switch (on)]
+    out:
+      - [1, switch (off)]
+    required:
+      - [1, switch puller]
+  - in:
+      - [1, pond broth]
+    out:
+      - [8, primordial soup]
+    required:
+      - [1, siphon]
+known: [flower, rock]
+world:
+  dsl: |
+    let
+      flowerNoise = perlin seed 1 0.15 0.0,
+      soupNoise = perlin seed 2 0.04 1.0,
+
+      flowers = flowerNoise > 0.70,
+      soup = soupNoise > 0.9
+    in
+      overlay
+      [ {grass}
+      , mask (flowers && (x - y) % 3 == 0) {daisy}
+      , mask soup {clover}
+      ]
+  upperleft: [-2, 4]
+  mask: 'q'
+  palette:
+    'z': [stone, wall]
+    '.': [stone, erase]
+    'G':
+      cell: [stone, erase]
+    'o': [stone, erase]
+    'd': [dirt, dahlia]
+    'v': [stone, erase, lab, keeper]
+    '0':
+      cell: [stone, switch (off), resetter]
+      waypoint:
+        name: switch
+    'D':
+      structure:
+        name: DNA decoder
+      cell: [floor, erase]
+    'E':
+      structure:
+        name: DNA sequencer
+      cell: [floor, erase]
+  placements:
+    - src: pond
+      offset: [-17, -10]
+    - src: fairy ring
+      offset: [-5, -25]
+  map: |
+    dzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
+    dzv.........................................z
+    zzz........oo...............................z
+    ............o...............................z
+    zzz........oo...............................z
+    dz.....Eooooooooooooooooooooooooooooooo.....z
+    dz.....o..............................o.....z
+    dz.....o..............................o.....z
+    dz.....oooooooooooooooooooooooooooooooo.....z
+    qz..........................................z
+    qzzzzzzzzz.zzzzzzzzzzzzzzzzzzzzzzzz.zzzzzzzzz
+    qqqqqqqqqzGzqqqqqqqqqqqqqqqqqqqqqqzGzqqqqqqqq
+    qzzzzzzzzz.zzzzzzzzzzzzzzzzzzzzzzzz.zzzzzzzzz
+    qz..........................................z
+    qzz....D....................................z
+    qz0.........................................z
+    qzz.........................................z
+    qz..........................................z
+    qz..........................................z
+    qz..........................................z
+    qz..........................................z
+    qz..........................................z
+    qzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
diff --git a/test/integration/Main.hs b/test/integration/Main.hs
index 714e53eb9..67341427f 100644
--- a/test/integration/Main.hs
+++ b/test/integration/Main.hs
@@ -241,6 +241,7 @@ testScenarioSolutions rs ui key =
         , testSolution (Sec 10) "Challenges/gopher"
         , testSolution (Sec 5) "Challenges/hackman"
         , testSolution (Sec 5) "Challenges/blender"
+        , testSolution (Sec 10) "Challenges/dna"
         , testSolution (Sec 10) "Challenges/hanoi"
         , testSolution (Sec 3) "Challenges/lights-out"
         , testSolution (Sec 10) "Challenges/Sliding Puzzles/3x3"