workspaceify
This commit is contained in:
@@ -0,0 +1,546 @@
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use crate::game::{Archetype, Board, FontSpec, Glyph, ObjectDef, Player, PortalDef};
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use color::Rgba8;
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use serde::{Deserialize, Serialize};
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use std::collections::HashMap;
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use std::convert::TryFrom;
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use std::path::Path;
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/// The top-level serialization/deserialization type for a `.toml` map file.
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///
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/// This struct mirrors the TOML file structure exactly. On load it is
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/// immediately converted into a [`Board`] via [`TryFrom<MapFile>`] and then
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/// discarded. On save a [`Board`] is converted back into this struct via
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/// [`From<&Board>`] before serialization.
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///
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/// See `maps/start.toml` for a complete example of the file format.
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#[derive(Deserialize, Serialize)]
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pub struct MapFile {
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/// The `[map]` section: name, dimensions, player start position.
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pub map: MapHeader,
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/// The `[palette]` section: maps single-character keys to tile definitions.
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pub palette: HashMap<String, PaletteEntry>,
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/// The `[grid]` section: the multi-line string that defines cell layout.
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pub grid: GridData,
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/// Optional `[font]` section specifying a bitmap font for this board.
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#[serde(default, skip_serializing_if = "Option::is_none")]
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pub font: Option<FontHeader>,
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/// Any `[[objects]]` entries. Optional; defaults to empty.
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#[serde(default, skip_serializing_if = "Vec::is_empty")]
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pub(crate) objects: Vec<MapFileObjectEntry>,
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/// Any `[[portals]]` entries. Optional; defaults to empty.
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#[serde(default, skip_serializing_if = "Vec::is_empty")]
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pub portals: Vec<PortalDef>,
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/// The `[scripts]` table: maps script names to Rhai source text.
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/// Optional; defaults to empty.
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#[serde(default, skip_serializing_if = "HashMap::is_empty")]
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pub scripts: HashMap<String, String>,
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}
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/// The `[map]` header section of a map file.
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#[derive(Deserialize, Serialize)]
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pub struct MapHeader {
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/// Human-readable name for this board, e.g. `"Opening Room"`.
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pub name: String,
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/// Width of the board in cells. Must match the length of every row in `[grid] content`.
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pub width: usize,
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/// Height of the board in cells. Must match the number of rows in `[grid] content`.
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pub height: usize,
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/// Starting position of the player as `[x, y]` (0-indexed, origin top-left).
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pub player_start: [i32; 2],
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/// Name of the board-level script in the `[scripts]` table, if any.
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#[serde(default, skip_serializing_if = "Option::is_none")]
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pub board_script_name: Option<String>,
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}
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/// The `[font]` section of a map file, specifying a bitmap font for this board.
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///
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/// When absent, the app's default embedded CP437 font is used.
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#[derive(Deserialize, Serialize)]
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pub struct FontHeader {
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/// Path to the PNG font image, relative to the working directory.
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pub path: String,
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/// Width of each tile in the font image, in pixels.
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pub tile_w: u32,
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/// Height of each tile in the font image, in pixels.
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pub tile_h: u32,
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}
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/// A tile index in a palette entry: either a plain integer or a character literal.
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///
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/// Accepting both forms lets map files use `tile = 32` for new files or
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/// `tile = " "` for convenience (the char is converted to its Unicode scalar).
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/// This means existing maps that used `ch = "#"` can be migrated by renaming
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/// the key to `tile`; the char form keeps working.
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#[derive(Deserialize, Serialize)]
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#[serde(untagged)]
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pub(crate) enum TileIndex {
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/// A direct tile index (e.g. `tile = 35`).
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Num(u32),
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/// A single-character shorthand (e.g. `tile = "#"`); converted to its Unicode scalar.
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Chr(char),
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}
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impl TileIndex {
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pub(crate) fn into_u32(self) -> u32 {
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match self {
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TileIndex::Num(n) => n,
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TileIndex::Chr(c) => c as u32,
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}
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}
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}
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/// One entry in the `[palette]` table.
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///
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/// Each entry is keyed by a single character (e.g. `"#"` or `" "`).
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/// That character is used in the `[grid]` content string to place tiles.
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/// The entry defines both how the tile looks (`tile`, `fg`, `bg`) and which
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/// [`Archetype`] it uses for behavior.
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///
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/// `tile` accepts either an integer (`tile = 35`) or a char (`tile = "#"`).
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#[derive(Deserialize, Serialize)]
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pub struct PaletteEntry {
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/// The archetype name for this tile, e.g. `"wall"` or `"empty"`.
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pub archetype: String,
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/// The tile index into the board's bitmap font.
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/// Accepts either an integer or a single-character string.
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tile: TileIndex,
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/// Foreground color as an `"#RRGGBB"` hex string.
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pub fg: String,
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/// Background color as an `"#RRGGBB"` hex string.
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pub bg: String,
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}
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/// The `[grid]` section of a map file.
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///
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/// `content` is a TOML multi-line string. Each line is one row of the board;
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/// each character in a line is looked up in the palette to determine the
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/// tile for that cell.
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#[derive(Deserialize, Serialize)]
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pub struct GridData {
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/// The raw grid content. Split by [`str::lines`] during loading.
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pub content: String,
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}
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/// One `[[objects]]` entry in a map file.
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///
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/// Used only for TOML serialization/deserialization. Converted to/from
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/// [`ObjectDef`] (which holds a [`Glyph`] directly) in the [`TryFrom`] /
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/// [`From`] impls below.
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#[derive(Deserialize, Serialize)]
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pub(crate) struct MapFileObjectEntry {
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/// Column of this object on the board (0-indexed).
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x: usize,
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/// Row of this object on the board (0-indexed).
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y: usize,
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/// Tile index into the board's bitmap font. Accepts integer or single-char string.
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tile: TileIndex,
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/// Foreground color as an `"#RRGGBB"` hex string.
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fg: String,
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/// Background color as an `"#RRGGBB"` hex string.
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bg: String,
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/// Name of the Rhai script in the `[scripts]` table, if any.
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#[serde(default, skip_serializing_if = "Option::is_none")]
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script_name: Option<String>,
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}
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/// Parses an `"#RRGGBB"` hex color string into an [`Rgba8`].
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/// Returns opaque black on any parse failure.
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fn parse_color(hex: &str) -> Rgba8 {
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let hex = hex.trim_start_matches('#');
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if hex.len() != 6 {
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return Rgba8 { r: 0, g: 0, b: 0, a: 255 };
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}
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let r = u8::from_str_radix(&hex[0..2], 16).unwrap_or(0);
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let g = u8::from_str_radix(&hex[2..4], 16).unwrap_or(0);
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let b = u8::from_str_radix(&hex[4..6], 16).unwrap_or(0);
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Rgba8 { r, g, b, a: 255 }
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}
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/// Converts an [`Rgba8`] to an `"#RRGGBB"` hex string (alpha is ignored).
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fn color_to_hex(color: Rgba8) -> String {
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format!("#{:02X}{:02X}{:02X}", color.r, color.g, color.b)
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}
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/// Converts a parsed map file into a runtime [`Board`].
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///
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/// Returns `Err(String)` if the grid dimensions do not match the header:
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/// - wrong number of rows (actual row count ≠ `height`)
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/// - any row whose character count ≠ `width`
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///
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/// The conversion proceeds in two passes:
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///
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/// 1. **Palette pass** — each entry is parsed into a `(Glyph, Archetype)` pair
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/// and stored in a temporary `HashMap` keyed by the palette character.
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/// Unknown archetype names produce an [`Archetype::ErrorBlock`] and a logged
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/// warning so malformed maps are visible in-game.
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///
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/// 2. **Grid pass** — `grid.content` is split into lines; each character is
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/// looked up in the palette map and pushed directly into `cells`.
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impl TryFrom<MapFile> for Board {
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type Error = String;
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fn try_from(mf: MapFile) -> Result<Self, Self::Error> {
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let w = mf.map.width;
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let h = mf.map.height;
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// Pass 1: build a char → (Glyph, Archetype) lookup from the palette.
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let mut palette: HashMap<char, (Glyph, Archetype)> = HashMap::new();
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for (key, entry) in mf.palette {
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let key_char = key.chars().next().unwrap_or(' ');
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let tile = entry.tile.into_u32();
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match Archetype::try_from(entry.archetype.as_str()) {
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Ok(archetype) => {
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let glyph = Glyph {
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tile,
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fg: parse_color(&entry.fg),
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bg: parse_color(&entry.bg),
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};
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palette.insert(key_char, (glyph, archetype));
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}
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Err(e) => {
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eprintln!("{e}");
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palette.insert(
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key_char,
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(Archetype::ErrorBlock.default_glyph(), Archetype::ErrorBlock),
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);
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}
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}
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}
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// Validate grid dimensions before walking cells.
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// Collect lines eagerly so we can check the count and reuse them.
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let rows: Vec<&str> = mf.grid.content.lines().collect();
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if rows.len() != h {
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return Err(format!(
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"grid has {} rows but map header declares height = {}",
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rows.len(),
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h
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));
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}
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for (i, line) in rows.iter().enumerate() {
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let col_count = line.chars().count();
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if col_count != w {
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return Err(format!(
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"grid row {} has {} characters but map header declares width = {}",
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i, col_count, w
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));
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}
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}
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// Pass 2: walk the validated grid and build cells.
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let mut cells: Vec<(Glyph, Archetype)> = Vec::with_capacity(w * h);
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for line in &rows {
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for ch in line.chars() {
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if let Some(&cell) = palette.get(&ch) {
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cells.push(cell);
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}
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}
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}
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let font = mf.font.map(|f| FontSpec {
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path: f.path,
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tile_w: f.tile_w,
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tile_h: f.tile_h,
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});
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// Convert MapFileObjectEntry → ObjectDef, resolving tile index and color strings.
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let objects = mf
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.objects
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.into_iter()
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.map(|e| ObjectDef {
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x: e.x,
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y: e.y,
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glyph: Glyph {
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tile: e.tile.into_u32(),
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fg: parse_color(&e.fg),
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bg: parse_color(&e.bg),
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},
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script_name: e.script_name,
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})
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.collect();
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Ok(Board {
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name: mf.map.name,
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width: w,
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height: h,
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cells,
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player: Player {
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x: mf.map.player_start[0],
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y: mf.map.player_start[1],
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},
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objects,
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portals: mf.portals,
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font,
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scripts: mf.scripts,
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board_script_name: mf.map.board_script_name,
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})
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}
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}
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/// Converts a runtime [`Board`] back into a serializable [`MapFile`].
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///
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/// The palette is reconstructed by enumerating unique `(Glyph, Archetype)`
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/// combinations in the board's cells and assigning each a single printable
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/// ASCII character key. The grid is rebuilt by looking up each cell in the
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/// resulting palette map.
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impl From<&Board> for MapFile {
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fn from(board: &Board) -> Self {
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// Pool for non-empty archetypes: printable ASCII 33-126 ('!' onward),
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// excluding `"` and `\` which would require escaping inside TOML strings.
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// Space (32) is reserved exclusively for Archetype::Empty.
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let pool: Vec<char> = (33u8..=126u8)
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.filter(|&b| b != b'"' && b != b'\\')
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.map(|b| b as char)
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.collect();
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let mut pool_iter = pool.iter();
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// The canonical empty cell (tile 32, black/black) is always serialized as ' '.
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// Every other unique (Glyph, Archetype) pair draws from the pool above.
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let canonical_empty = (Archetype::Empty.default_glyph(), Archetype::Empty);
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let mut cell_to_key: HashMap<(Glyph, Archetype), char> = HashMap::new();
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let mut palette: HashMap<String, PaletteEntry> = HashMap::new();
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for y in 0..board.height {
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for x in 0..board.width {
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let (glyph, arch) = board.get(x, y);
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let key = (*glyph, *arch);
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if !cell_to_key.contains_key(&key) {
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if key == canonical_empty {
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cell_to_key.insert(key, ' ');
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palette.insert(
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" ".to_string(),
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PaletteEntry {
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archetype: arch.name().to_string(),
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tile: TileIndex::Num(glyph.tile),
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fg: color_to_hex(glyph.fg),
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bg: color_to_hex(glyph.bg),
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},
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);
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} else {
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let ch = *pool_iter
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.next()
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.expect("board has more than 92 unique non-canonical cell types");
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cell_to_key.insert(key, ch);
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palette.insert(
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ch.to_string(),
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PaletteEntry {
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archetype: arch.name().to_string(),
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tile: TileIndex::Num(glyph.tile),
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fg: color_to_hex(glyph.fg),
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bg: color_to_hex(glyph.bg),
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},
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);
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}
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}
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}
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}
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// Pass 2: reconstruct the grid string row by row.
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let mut rows: Vec<String> = Vec::with_capacity(board.height);
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for y in 0..board.height {
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let mut row = String::with_capacity(board.width);
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for x in 0..board.width {
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let (glyph, arch) = board.get(x, y);
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row.push(cell_to_key[&(*glyph, *arch)]);
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}
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rows.push(row);
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}
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// Trailing newline ensures the last row is complete; str::lines handles it correctly.
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let content = rows.join("\n") + "\n";
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let font = board.font.as_ref().map(|f| FontHeader {
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path: f.path.clone(),
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tile_w: f.tile_w,
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tile_h: f.tile_h,
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});
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// Convert ObjectDef → MapFileObjectEntry, encoding the glyph as TOML-compatible fields.
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let objects: Vec<MapFileObjectEntry> = board
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.objects
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.iter()
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.map(|o| MapFileObjectEntry {
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x: o.x,
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y: o.y,
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tile: TileIndex::Num(o.glyph.tile),
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fg: color_to_hex(o.glyph.fg),
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bg: color_to_hex(o.glyph.bg),
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script_name: o.script_name.clone(),
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})
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.collect();
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let portals = board
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.portals
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.iter()
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.map(|p| PortalDef {
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x: p.x,
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y: p.y,
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target_map: p.target_map.clone(),
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target_entry: p.target_entry.clone(),
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})
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.collect();
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MapFile {
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map: MapHeader {
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name: board.name.clone(),
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width: board.width,
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height: board.height,
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player_start: [board.player.x, board.player.y],
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board_script_name: board.board_script_name.clone(),
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},
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palette,
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grid: GridData { content },
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font,
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objects,
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portals,
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scripts: board.scripts.clone(),
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}
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}
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}
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/// Loads a map file from disk and returns a ready-to-use [`Board`].
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///
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/// Reads the file at `path`, deserializes it as TOML into a [`MapFile`],
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/// then converts it via [`TryFrom<MapFile>`]. Propagates I/O errors, TOML
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/// parse errors, and grid dimension mismatches through the `Box<dyn Error>` return.
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pub fn load(path: &str) -> Result<Board, Box<dyn std::error::Error>> {
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let content = std::fs::read_to_string(path)?;
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let map_file: MapFile = toml::from_str(&content)?;
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Board::try_from(map_file).map_err(|e| e.into())
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}
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/// Serializes a [`Board`] to a `.toml` map file at `path`.
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///
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/// Converts the board to a [`MapFile`] via [`From<&Board>`], then serializes
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/// it with `toml::to_string_pretty`. Propagates I/O and serialization errors.
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pub fn save(board: &Board, path: &Path) -> Result<(), Box<dyn std::error::Error>> {
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let map_file = MapFile::from(board);
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let toml_str = toml::to_string_pretty(&map_file)?;
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std::fs::write(path, toml_str)?;
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Ok(())
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}
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#[cfg(test)]
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mod tests {
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use super::*;
|
||||
|
||||
/// Minimal valid TOML with a configurable grid, used as a base for dimension tests.
|
||||
fn minimal_toml(width: usize, height: usize, grid_rows: &[&str]) -> String {
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let content = grid_rows.join("\n");
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// Use r##"..."## so the "# in color strings does not close the raw string.
|
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format!(
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r##"
|
||||
[map]
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||||
name = "Test"
|
||||
width = {width}
|
||||
height = {height}
|
||||
player_start = [0, 0]
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||||
|
||||
[palette]
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"." = {{ archetype = "empty", tile = 46, fg = "#000000", bg = "#000000" }}
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||||
|
||||
[grid]
|
||||
content = """
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{content}
|
||||
"""
|
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"##
|
||||
)
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn grid_wrong_row_count_returns_error() {
|
||||
// height = 3 but only 2 rows in the grid
|
||||
let toml = minimal_toml(3, 3, &["...", "..."]);
|
||||
let mf: MapFile = toml::from_str(&toml).unwrap();
|
||||
let result = Board::try_from(mf);
|
||||
assert!(result.is_err());
|
||||
// Use .err().unwrap() instead of .unwrap_err() to avoid requiring Board: Debug.
|
||||
let msg = result.err().unwrap();
|
||||
assert!(msg.contains("2 rows"), "expected row count in error, got: {msg}");
|
||||
assert!(msg.contains("height = 3"), "expected declared height in error, got: {msg}");
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn grid_wrong_row_width_returns_error() {
|
||||
// width = 4 but second row is only 3 characters
|
||||
let toml = minimal_toml(4, 2, &["....", "..."]);
|
||||
let mf: MapFile = toml::from_str(&toml).unwrap();
|
||||
let result = Board::try_from(mf);
|
||||
assert!(result.is_err());
|
||||
let msg = result.err().unwrap();
|
||||
assert!(msg.contains("3 characters"), "expected col count in error, got: {msg}");
|
||||
assert!(msg.contains("width = 4"), "expected declared width in error, got: {msg}");
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn object_archetype_in_palette_produces_error_block() {
|
||||
// "object" is no longer a valid palette archetype; it should produce ErrorBlock.
|
||||
let toml = r##"
|
||||
[map]
|
||||
name = "Test"
|
||||
width = 1
|
||||
height = 1
|
||||
player_start = [0, 0]
|
||||
|
||||
[palette]
|
||||
"O" = { archetype = "object", tile = 64, fg = "#00FFFF", bg = "#000000" }
|
||||
|
||||
[grid]
|
||||
content = """
|
||||
O
|
||||
"""
|
||||
"##;
|
||||
let mf: MapFile = toml::from_str(toml).unwrap();
|
||||
let board = Board::try_from(mf).unwrap();
|
||||
let (_, arch) = board.get(0, 0);
|
||||
assert_eq!(*arch, crate::game::Archetype::ErrorBlock);
|
||||
}
|
||||
|
||||
#[test]
|
||||
fn object_glyph_round_trips_through_toml() {
|
||||
// Objects must survive a save→load cycle with their glyph intact.
|
||||
let toml = r##"
|
||||
[map]
|
||||
name = "Test"
|
||||
width = 3
|
||||
height = 3
|
||||
player_start = [0, 0]
|
||||
|
||||
[palette]
|
||||
"." = { archetype = "empty", tile = 46, fg = "#000000", bg = "#000000" }
|
||||
|
||||
[grid]
|
||||
content = """
|
||||
...
|
||||
...
|
||||
...
|
||||
"""
|
||||
|
||||
[[objects]]
|
||||
x = 1
|
||||
y = 1
|
||||
tile = 64
|
||||
fg = "#00FFFF"
|
||||
bg = "#000000"
|
||||
"##;
|
||||
let mf: MapFile = toml::from_str(toml).unwrap();
|
||||
let board = Board::try_from(mf).unwrap();
|
||||
assert_eq!(board.objects.len(), 1);
|
||||
let obj = &board.objects[0];
|
||||
assert_eq!(obj.x, 1);
|
||||
assert_eq!(obj.y, 1);
|
||||
assert_eq!(obj.glyph.tile, 64);
|
||||
assert_eq!(obj.glyph.fg, Rgba8 { r: 0x00, g: 0xFF, b: 0xFF, a: 255 });
|
||||
assert_eq!(obj.glyph.bg, Rgba8 { r: 0, g: 0, b: 0, a: 255 });
|
||||
|
||||
// Save back to TOML and reload; glyph must survive.
|
||||
let map_file = MapFile::from(&board);
|
||||
let toml_out = toml::to_string_pretty(&map_file).unwrap();
|
||||
let mf2: MapFile = toml::from_str(&toml_out).unwrap();
|
||||
let board2 = Board::try_from(mf2).unwrap();
|
||||
let obj2 = &board2.objects[0];
|
||||
assert_eq!(obj2.glyph.tile, obj.glyph.tile);
|
||||
assert_eq!(obj2.glyph.fg, obj.glyph.fg);
|
||||
assert_eq!(obj2.glyph.bg, obj.glyph.bg);
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user