skeleton of merge functionality

README.md

@@ -38,10 +38,16 @@ some more practical uses would be things like:
 ## todo
 
 * implement Result return types on ::from functions so that we can handle errors
-* replace Image with Vec<u8> or something. seems like a pointless abstraction
+* replace Image with Vec<u8> or something. seems like a pointless abstraction.
 * replace game avatar with helper functions to get and set the sprite with an ID of A
 * implement PartialEq for tiles etc. for the sake of checking for duplicate tiles?
 * dedupe functions for tiles, sprites, etc.
+* tests for merge function
+* merge function places merged avatar in room 0 instead of the merged room 0 with a new ID.
+* actually - any sprites from the merged game are in game A's rooms
+* merged rooms have the wrong palette IDs and tile IDs
+* exits in merged rooms do not work - the on-screen position is correct, but the room ID is wrong
+* add update function (i.e. migrate an old game version to the current one) - would this work?
 
 ### tidy up
 

src/bin/bitsy-merge.rs

@@ -0,0 +1,26 @@
+extern crate bitsy_parser;
+use bitsy_parser::game::Game;
+use std::{env, fs};
+
+fn main() {
+    let game_a = env::args()
+        .nth(1)
+        .expect("No main game specified. Usage: `bitsy-merge main.bitsy additional.bitsy output.bitsy`");
+
+    // todo allow numerous additional games
+    let game_b = env::args()
+        .nth(2)
+        .expect("No additional game specified. Usage: `bitsy-merge main.bitsy additional.bitsy output.bitsy`");
+
+    let outfile = env::args()
+        .nth(3)
+        .expect("No output file specified. Usage: `bitsy-merge main.bitsy additional.bitsy output.bitsy`");
+
+    let mut game_a = Game::from(fs::read_to_string(game_a).unwrap()).unwrap();
+    let     game_b = Game::from(fs::read_to_string(game_b).unwrap()).unwrap();
+
+    game_a.merge(game_b);
+
+    fs::write(outfile, game_a.to_string())
+        .expect("Failed to write output file");
+}

src/game.rs

@@ -1,6 +1,8 @@
-use crate::{Dialogue, Ending, Font, Item, Palette, Room, Sprite, TextDirection, Tile, Variable, transform_line_endings, segments_from_string, new_unique_id, try_id};
+use crate::{Dialogue, Ending, Font, Item, Palette, Room, Sprite, TextDirection, Tile, Variable, transform_line_endings, segments_from_string, new_unique_id, try_id, Instance};
 use loe::TransformMode;
 use std::str::FromStr;
+use std::collections::HashMap;
+use std::borrow::BorrowMut;
 
 /// in very early versions of Bitsy, room tiles were defined as single alphanumeric characters -
 /// so there was a maximum of 36 unique tiles. later versions are comma-separated.
@@ -328,42 +330,193 @@ impl Game {
         Ok(self.get_tiles_by_ids(tile_ids))
     }
 
-    // return? array of changes made? status?
+    // return? array of changes made? error/ok?
-    pub fn merge(game: Game) {
+    pub fn merge(&mut self, game: Game) {
         // ignore title, version, room format, room type, font, text direction
 
         // maybe we need hashmaps of old->new IDs, for each type of ID?
         // we need functions for "add sprite" etc. that return the newly generated valid ID
 
-        // for each new palette:
+        let mut palette_id_changes:  HashMap<String, String> = HashMap::new();
-        //     check if a matching palette exists
+        let mut tile_id_changes:     HashMap<String, String> = HashMap::new();
-        //         if yes, replace any room palette IDs with the extant palette ID
+        let mut dialogue_id_changes: HashMap<String, String> = HashMap::new();
-        //     check if palette ID clashes with an existing palette ID
+        let mut ending_id_changes:   HashMap<String, String> = HashMap::new();
-        //     check if palette name clashes and if so, give a new name ("[name] 2" or something)
+        let mut item_id_changes:     HashMap<String, String> = HashMap::new();
+        let mut room_id_changes:     HashMap<String, String> = HashMap::new();
+        let mut sprite_id_changes:   HashMap<String, String> = HashMap::new();
 
-        // for each tile:
+        fn insert_if_different(map: &mut HashMap<String, String>, old: String, new: String) {
-        //     check if a matching tile exists
+            if old != new {
-        //         if yes, replace room tile IDs with that of the extant tile
+                map.insert(old, new);
-        //         if no, give a new unique tile ID and change room tile IDs to this
+            }
+        }
 
-        // ignore avatar (maybe convert to normal sprite instead?)
+        // alternatively - instead of handling these types in a specific order,
+        // we could calculate the new IDs for each type first,
+        // then handle the sections one by one
 
-        // for each item
+        // a room has a palette, so handle palettes before rooms
+        for palette in game.palettes {
+            let new_id = self.add_palette(palette.clone());
+            insert_if_different(palette_id_changes.borrow_mut(), palette.id.clone(),new_id);
+        }
 
-        // for each dialogue item
+        // a room has tiles, so handle before room
+        for tile in game.tiles {
+            let new_id = self.add_tile(tile.clone());
+            insert_if_different(tile_id_changes.borrow_mut(), tile.id.clone(), new_id);
+        }
 
-        // for each ending
+        for variable in game.variables {
+            // don't change ID - just avoid duplicates
+            if ! self.variable_ids().contains(&variable.id) {
+                self.add_variable(variable.clone());
+            }
+        }
 
-        // for each variable
+        for item in &game.items {
+            let old_id = item.id.clone();
+            let new_id = try_id(self.item_ids(), item.id.clone());
+            insert_if_different(item_id_changes.borrow_mut(), old_id, new_id)
+        }
 
-        // for each room
+        // a sprite has a dialogue, so handle before sprites
-        //     give room a new unique ID
+        // dialogue can have variables, so handle before after variables
-        //     check room name - if duplicate, append "2" or something?
+        for dialogue in game.dialogues {
-        //     convert tile/item IDs to new ones
+            let mut dialogue = dialogue.clone();
-        //     add room to game
 
-        // for each sprite
+            for (old, new) in &item_id_changes {
-        //
+                // todo is there a better way of doing this?
+                dialogue.contents = dialogue.contents.replace(
+                    &format!("item \"{}\"", old),
+                    &format!("item \"{}\"", new)
+                );
+            }
+
+            let old_id = dialogue.id.clone();
+            let new_id = self.add_dialogue(dialogue);
+            insert_if_different(dialogue_id_changes.borrow_mut(), old_id, new_id);
+        }
+
+        // an ending lives in a room, so handle endings before rooms
+        for ending in game.endings {
+            let new_id = self.add_ending(ending.clone());
+            insert_if_different(ending_id_changes.borrow_mut(), ending.id.clone(), new_id);
+        }
+
+        // an item has a dialogue ID, so we need to handle these after dialogues
+        // an item instance lives in a room so these must be handled before rooms
+        for item in &game.items {
+            let mut item = item.clone();
+
+            if item_id_changes.contains_key(&item.id) {
+                item.id = item_id_changes[&item.id].clone();
+            }
+
+            if item.dialogue_id.is_some() {
+                let key = item.dialogue_id.clone().unwrap();
+                if dialogue_id_changes.contains_key(&key) {
+                    item.dialogue_id = Some(dialogue_id_changes[&key].clone());
+                }
+            }
+
+            self.add_item(item);
+        }
+
+        // calculate all of the new room IDs first
+        // to insert any new room, we need to know the new IDs of every room
+        // to maintain the integrity of exits and endings
+        for room in &game.rooms {
+            let new_id = try_id(self.room_ids(), room.id.clone());
+            insert_if_different(room_id_changes.borrow_mut(), room.id.clone(), new_id);
+        }
+
+        // needs to be handled after palettes, tiles, items, exits, endings
+        // and before sprites
+        for room in &game.rooms {
+            let mut room = room.clone();
+
+            if room_id_changes.contains_key(&room.id) {
+                room.id = room_id_changes[&room.id].clone();
+            }
+
+            if room.palette_id.is_some()  {
+                let key = room.palette_id.clone().unwrap();
+                if palette_id_changes.contains_key(&key) {
+                    room.palette_id = Some(room_id_changes[&key].clone());
+                }
+            }
+
+            let mut tiles = Vec::new();
+            for tile_id in &room.tiles {
+                tiles.push(if tile_id_changes.contains_key(tile_id) {
+                    tile_id_changes.get(tile_id).unwrap()
+                } else {
+                    tile_id
+                }.clone());
+            }
+            room.tiles = tiles;
+
+            room.items = room.items.iter().map(|instance|
+                if item_id_changes.contains_key(&instance.id) {
+                    Instance {
+                        position: instance.position.clone(),
+                        id: item_id_changes[&instance.id].clone()
+                    }
+                } else {
+                    instance.clone()
+                }
+            ).collect();
+
+            room.exits = room.exits.iter().map(|exit| {
+                let mut exit = exit.clone();
+                if room_id_changes.contains_key(&exit.exit.room_id) {
+                    exit.exit.room_id = room_id_changes[&exit.exit.room_id].clone();
+                }
+                exit
+            }).collect();
+
+            room.endings = room.endings.iter().map(|ending| {
+                let mut ending = ending.clone();
+                if ending_id_changes.contains_key(&ending.id) {
+                    ending.id = ending_id_changes[&ending.id].clone();
+                }
+                ending
+            }).collect();
+
+            self.add_room(room.to_owned());
+        }
+
+        // a sprite has a dialogue ID, so we need to handle these after dialogues
+        // a sprite has a position in a room, so we need to handle these after the rooms
+        for sprite in game.sprites {
+            let mut sprite = sprite.clone();
+            // avoid having two avatars
+            if sprite.id == "A".to_string() {
+                sprite.id = "0".to_string(); // just a default value for replacement
+            }
+
+            if sprite.dialogue_id.is_some() {
+                let key = sprite.dialogue_id.clone().unwrap();
+                if dialogue_id_changes.contains_key(&key) {
+                    sprite.dialogue_id = Some(dialogue_id_changes[&key].clone());
+                }
+            }
+
+            if sprite.room_id.is_some() {
+                let key = sprite.room_id.clone().unwrap();
+                if room_id_changes.contains_key(&key) {
+                    sprite.room_id = Some(room_id_changes[&key].clone());
+                }
+            }
+
+            let old_id = sprite.id.clone();
+            let new_id = self.add_sprite(sprite);
+            insert_if_different(sprite_id_changes.borrow_mut(), old_id, new_id);
+        }
+
+        // does deduplication need to be its own function?
+        // should this function just add everything and we can dedupe later?
     }
 }
 
@@ -559,6 +712,35 @@ impl Game {
         new_id
     }
 
+    pub fn add_ending(&mut self, mut ending: Ending) -> String {
+        let new_id = try_id(self.ending_ids(), ending.id.clone());
+        if new_id != ending.id {
+            ending.id = new_id.clone();
+        }
+        self.endings.push(ending);
+        new_id
+    }
+
+    /// Safely adds a room and returns the room ID (a new ID will be generated if clashing)
+    /// You will need to be mindful that the room's palette, tile, exit and ending IDs
+    /// will be valid after adding.
+    pub fn add_room(&mut self, mut room: Room) -> String {
+        let new_id = try_id(self.room_ids(), room.id.clone());
+        if new_id != room.id {
+            room.id = new_id.clone();
+        }
+        self.rooms.push(room);
+        new_id
+    }
+
+    pub fn add_variable(&mut self, mut variable: Variable) -> String {
+        let new_id = try_id(self.variable_ids(), variable.id.clone());
+        if new_id != variable.id {
+            variable.id = new_id.clone();
+        }
+        new_id
+    }
+
     #[inline]
     fn version_line(&self) -> String {
         if self.version.is_some() {
@@ -714,4 +896,24 @@ mod test {
         game.add_item(crate::mock::item());
         assert_eq!(game.item_ids(), vec!["0".to_string(), "6".to_string(), "1".to_string()]);
     }
+
+    #[test]
+    fn test_merge() {
+        // try merging two default games
+        let mut game = crate::mock::game_default();
+        game.merge(crate::mock::game_default());
+
+        assert_eq!(game.room_ids(), vec!["0".to_string(), "1".to_string()]);
+        assert_eq!(game.tile_ids(), vec!["a".to_string(), "1".to_string()]); // 0 is reserved
+        // duplicate avatar (SPR A) gets converted into a normal sprite
+        assert_eq!(
+            game.sprite_ids(),
+            vec!["A".to_string(), "a".to_string(), "0".to_string(), "1".to_string()]
+        );
+        assert_eq!(game.item_ids(), vec!["0".to_string(), "1".to_string()]);
+        assert_eq!(
+            game.dialogue_ids(),
+            vec!["SPR_0".to_string(), "ITM_0".to_string(), "0".to_string(), "1".to_string()]
+        )
+    }
 }

src/lib.rs

@@ -37,11 +37,12 @@ use std::fmt::Display;
 use text::{Font, TextDirection};
 use tile::Tile;
 use variable::Variable;
+use std::num::ParseIntError;
 
 #[derive(Clone, Debug, Eq, PartialEq)]
 pub struct Instance {
     position: Position,
-    id: String, // item / ending.rs id
+    id: String, // item / ending id
 }
 
 #[derive(Clone, Debug, Eq, PartialEq)]
@@ -75,8 +76,8 @@ impl AnimationFrames for Vec<Image> {
 }
 
 #[inline]
-fn from_base36(str: &str) -> u64 {
+fn from_base36(str: &str) -> Result<u64, ParseIntError> {
-    u64::from_str_radix(str, 36).expect(&format!("Invalid base36 string: {}", str))
+    u64::from_str_radix(str, 36)
 }
 
 /// this doesn't work inside ToBase36 for some reason
@@ -171,11 +172,14 @@ fn new_unique_id(mut ids: Vec<String>) -> String {
     let mut new_id: u64 = 0;
 
     for id in ids {
-        if new_id != from_base36(&id) {
+        let id= from_base36(&id);
-            break;
+        if id.is_ok() {
-        }
+            if new_id != id.unwrap() {
+                break;
+            }
 
-        new_id += 1;
+            new_id += 1;
+        }
     }
 
     return to_base36(new_id);
@@ -209,9 +213,9 @@ mod test {
 
     #[test]
     fn test_from_base36() {
-        assert_eq!(from_base36("0"), 0);
+        assert_eq!(from_base36("0").unwrap(), 0);
-        assert_eq!(from_base36("0z"), 35);
+        assert_eq!(from_base36("0z").unwrap(), 35);
-        assert_eq!(from_base36("11"), 37);
+        assert_eq!(from_base36("11").unwrap(), 37);
     }
 
     #[test]