3 files changed, 27 insertions, 5 deletions
diff --git a/server/data/src/book/diagram_layout.rs b/server/data/src/book/diagram_layout.rs
index 0ea26a69..29240b69 100644
--- a/server/data/src/book/diagram_layout.rs
+++ b/server/data/src/book/diagram_layout.rs
@@ -32,6 +32,11 @@ pub struct Layout {
 }
 
 pub fn diagram_layout(diagram: &mut Diagram) -> Result<()> {
+    // seems to have problems with a single node
+    if diagram.nodes.len() < 2 {
+        return Ok(());
+    }
+
     let mut child = Command::new("dot")
         .arg("-Tjson")
         .arg("-Kdot")
diff --git a/server/data/src/book/mod.rs b/server/data/src/book/mod.rs
index 263e8111..a0776f41 100644
--- a/server/data/src/book/mod.rs
+++ b/server/data/src/book/mod.rs
@@ -23,7 +23,7 @@ use crate::{
     Serverdata,
     book::{diagram_layout::diagram_layout, recipe_diagram::recipe_diagram},
 };
-use anyhow::Result;
+use anyhow::{Context, Result};
 use hurrycurry_locale::trm;
 use hurrycurry_protocol::{
     Gamedata, Message,
@@ -40,9 +40,16 @@ pub fn book(data: &Gamedata, serverdata: &Serverdata) -> Result<Book> {
     let mut toc = Vec::new();
 
     for (name, repr) in serverdata.recipe_groups.clone() {
-        let repr = repr.into_iter().collect::<Vec<_>>();
+        let repr = repr
+            .into_iter()
+            .filter(|&i| data.demands.iter().any(|d| d.input == i))
+            .collect::<Vec<_>>();
+        if repr.is_empty() {
+            continue;
+        }
+
         let mut diagram = recipe_diagram(data, serverdata, &repr)?;
-        diagram_layout(&mut diagram)?;
+        diagram_layout(&mut diagram).context("during layouting")?;
         let title = Message::Translation {
             id: format!("b.{name}.title"),
             params: vec![],
diff --git a/server/data/src/book/recipe_diagram.rs b/server/data/src/book/recipe_diagram.rs
index a4b9a7b1..6ec9965f 100644
--- a/server/data/src/book/recipe_diagram.rs
+++ b/server/data/src/book/recipe_diagram.rs
@@ -17,7 +17,7 @@
 */
 
 use crate::Serverdata;
-use anyhow::Result;
+use anyhow::{Result, bail};
 use hurrycurry_protocol::{
     Gamedata, ItemIndex, Message, Recipe, RecipeIndex,
     book::{Diagram, DiagramEdge, DiagramNode, NodeStyle},
@@ -44,6 +44,11 @@ pub fn recipe_diagram(
     let mut have = BTreeSet::<ItemIndex>::new();
     let mut recipes = BTreeSet::new();
 
+    // If an ambient item is the target it must be moved from 'need' to 'have' early
+    for i in &ambient_items {
+        have.extend(need.take(i));
+    }
+
     #[derive(PartialEq, PartialOrd, Eq, Ord)]
     struct GraphRecipe {
         index: RecipeIndex,
@@ -51,7 +56,8 @@ pub fn recipe_diagram(
         outputs: Vec<ItemIndex>,
     }
 
-    while let Some(item) = need.pop_last() {
+    while let Some(item) = need.pop_first() {
+        let mut found_recipe = false;
         for (ri, r) in data.recipes() {
             if r.outputs().contains(&item) {
                 let gr = GraphRecipe {
@@ -72,8 +78,12 @@ pub fn recipe_diagram(
                 need.extend(gr.inputs.iter().filter(|i| !have.contains(&i)));
                 have.extend(&gr.outputs);
                 recipes.insert(gr);
+                found_recipe = true;
             }
         }
+        if !found_recipe {
+            bail!("stuck at making {}", data.item_name(item))
+        }
     }
 
     let mut diag = Diagram::default();