use crate::background::{ScatterContext, check_rect, scatter};
use crate::scene::Budget;
use crate::*;
use std::collections::{HashMap, HashSet};
use std::sync::Arc;
pub struct BackgroundBuilder<'a> {
doc: &'a Document,
background: Background,
limits: Limits,
budget: Budget,
sprites: HashMap<String, Arc<Sprite>>,
operations: HashSet<String>,
}
impl Background {
pub fn builder<'a>(
doc: &'a Document,
name: &str,
size: (u32, u32),
seed: u64,
limits: &Limits,
) -> Result<BackgroundBuilder<'a>> {
check_name(name)?;
check_size(size, limits)?;
let mut budget = Budget::new(limits);
budget.pixels(doc.scene_storage())?;
budget.commands(doc.scene_commands())?;
Ok(BackgroundBuilder {
doc,
background: Background {
commands: 0,
name: name.into(),
width: size.0,
height: size.1,
seed,
layers: Vec::new(),
},
limits: limits.clone(),
budget,
sprites: HashMap::new(),
operations: HashSet::new(),
})
}
}
pub(crate) fn check_name(name: &str) -> Result<()> {
if name.is_empty()
|| !name
.chars()
.all(|c| c.is_ascii_alphanumeric() || matches!(c, '_' | '-'))
{
return Err(Error::invalid(
"Scene name must contain ASCII letters, digits, underscores or hyphens",
));
}
Ok(())
}
fn check_size(size: (u32, u32), limits: &Limits) -> Result<()> {
if size.0 == 0 || size.1 == 0 {
return Err(Error::invalid("Scene size must be positive"));
}
limits.check_image(size.0, size.1)
}
impl BackgroundBuilder<'_> {
pub fn layer(
&mut self,
name: &str,
size: (u32, u32),
options: LayerOptions,
) -> Result<&mut Self> {
check_name(name)?;
check_size(size, &self.limits)?;
if size.0 > i32::MAX as u32 || size.1 > i32::MAX as u32 {
return Err(Error::limit("Layer coordinates exceed signed range"));
}
if self.background.layers.len() >= self.limits.max_layers {
return Err(Error::limit("Too many background layers"));
}
if self.background.layers.iter().any(|l| l.name == name) {
return Err(Error::new(
ErrorCode::DuplicateName,
"Duplicate background layer",
));
}
if let Some(clip) = options.clip {
check_rect(clip, size)?;
}
self.budget.commands(1)?;
self.background.commands += 1;
self.operations.clear();
self.background.layers.push(BackgroundLayer {
name: name.into(),
width: size.0,
height: size.1,
options,
items: Vec::new(),
position: Position::new(1, 1),
});
Ok(self)
}
fn resolve(&mut self, source: &SourceRef) -> Result<(SourceRef, Option<Arc<Sprite>>)> {
match source {
SourceRef::Sprite(name) => {
let canonical = crate::text::scene_chain_name(name, &self.limits)?;
if let Some(s) = self.sprites.get(&canonical) {
return Ok((SourceRef::Sprite(canonical), Some(s.clone())));
}
let (name, sprite) =
crate::text::scene_chain(name, self.doc, &self.limits, &mut self.budget)?;
let sprite = Arc::new(sprite);
self.sprites.insert(name.clone(), sprite.clone());
Ok((SourceRef::Sprite(name), Some(sprite)))
}
_ => Ok((source.clone(), None)),
}
}
pub fn place(&mut self, source: SourceRef, options: PlacementOptions) -> Result<&mut Self> {
if self.background.layers.is_empty() {
return Err(Error::invalid("Add a layer before placing sources"));
}
self.budget.commands(1)?;
self.background.commands += 1;
let (source, sprite) = self.resolve(&source)?;
let placement = BackgroundPlacement {
source,
sprite,
options,
position: Position::new(1, 1),
};
placement.crop(placement.view(self.doc)?.size()?)?;
self.budget.pixels(1)?;
self.background
.layers
.last_mut()
.unwrap()
.items
.push(placement);
Ok(self)
}
pub fn scatter(
&mut self,
name: &str,
options: &ScatterOptions,
variants: &[WeightedVariant],
) -> Result<&mut Self> {
check_name(name)?;
if !self.operations.insert(name.into()) {
return Err(Error::new(
ErrorCode::DuplicateName,
"Duplicate layer operation",
));
}
self.budget.commands(
variants
.len()
.checked_add(1)
.ok_or_else(|| Error::limit("Scene command overflow"))?,
)?;
self.background.commands += 1 + variants.len();
let mut resolved = Vec::new();
for variant in variants {
let (source, sprite) = self.resolve(&variant.source)?;
resolved.push((
WeightedVariant {
source,
weight: variant.weight,
},
sprite,
));
}
let layer = self
.background
.layers
.last()
.ok_or_else(|| Error::invalid("Add a layer before scattering"))?;
let items = scatter(
self.doc,
ScatterContext {
background: &self.background.name,
layer,
operation: name,
owner_seed: self.background.seed,
position: Position::new(1, 1),
},
options,
&resolved,
&mut self.budget,
)?;
self.background
.layers
.last_mut()
.unwrap()
.items
.extend(items);
Ok(self)
}
pub fn finish(self) -> Background {
self.background
}
}
impl Document {
pub fn with_surface(&self, mut surface: Surface, limits: &Limits) -> Result<Document> {
self.check_new_definition(limits)?;
if self.surface(surface.name()).is_some() {
return Err(Error::new(ErrorCode::DuplicateName, "Duplicate surface"));
}
limits.check_image(surface.width, surface.height)?;
let palette = self.palette(surface.palette.name()).ok_or_else(|| {
Error::new(
ErrorCode::UnknownName,
"Surface palette must exist in receiver document",
)
})?;
if surface
.keys
.iter()
.any(|&k| k != crate::sprite::EMPTY && palette.color(k).is_none())
{
return Err(Error::new(
ErrorCode::UnknownName,
"Surface key is absent from receiver palette",
));
}
surface.palette = palette.clone();
let mut b = Budget::new(limits);
b.pixels(self.scene_storage())?;
b.pixels(surface.storage())?;
b.commands(
self.scene_commands()
.checked_add(surface.commands)
.ok_or_else(|| Error::limit("Scene command overflow"))?,
)?;
let mut doc = self.clone();
doc.surfaces.push(surface);
Ok(doc)
}
pub fn with_background(&self, background: Background, limits: &Limits) -> Result<Document> {
self.check_new_definition(limits)?;
if self.background(background.name()).is_some() {
return Err(Error::new(ErrorCode::DuplicateName, "Duplicate background"));
}
limits.check_image(background.width, background.height)?;
if background.layers.len() > limits.max_layers {
return Err(Error::limit("Too many background layers"));
}
for layer in &background.layers {
limits.check_image(layer.width, layer.height)?;
if let Some(clip) = layer.options.clip {
check_rect(clip, layer.size())?;
}
for p in &layer.items {
p.crop(p.view(self)?.size()?)?;
if let Some(s) = &p.sprite {
s.effect_size(s.width, s.height, s.layers.len(), limits)?;
let palette = self.palette(s.palette.name()).ok_or_else(|| {
Error::new(
ErrorCode::UnknownName,
"Background sprite palette is absent from receiver",
)
})?;
if let Some(key) = s.missing_key(palette) {
return Err(Error::new(
ErrorCode::UnknownName,
format!("Background key `{key}` is absent from receiver palette"),
));
}
}
}
}
let mut b = Budget::new(limits);
let mut shared = HashSet::new();
b.pixels(self.scene_storage_seen(&mut shared))?;
b.pixels(background.storage(&mut shared))?;
b.commands(
self.scene_commands()
.checked_add(background.commands)
.ok_or_else(|| Error::limit("Scene command overflow"))?,
)?;
let mut doc = self.clone();
doc.backgrounds.push(background);
Ok(doc)
}
fn check_new_definition(&self, limits: &Limits) -> Result<()> {
let count = self.palettes.len()
+ self.sprites.len()
+ self.animations.len()
+ self.tilesets.len()
+ self.tilemaps.len()
+ self.fonts.len()
+ self.groups.len()
+ self.screens.len()
+ self.themes.len()
+ self.states.len()
+ self.icon_sets.len()
+ self.surfaces.len()
+ self.backgrounds.len();
if count >= limits.max_definitions {
Err(Error::limit("More than the definition limit"))
} else {
Ok(())
}
}
}