From e8c03b953671c2f467f19992b3b8cac28cdf6cff Mon Sep 17 00:00:00 2001
From: Timothy Warren <twarren@nabancard.com>
Date: Fri, 3 Dec 2021 14:15:17 -0500
Subject: [PATCH] Add corridors to the bsp interior map builder, completing
 section 4.4

---
 src/map_builders/bsp_interior.rs | 46 ++++++++++++++++++++++++++++++--
 src/map_builders/mod.rs          |  3 ++-
 2 files changed, 46 insertions(+), 3 deletions(-)

diff --git a/src/map_builders/bsp_interior.rs b/src/map_builders/bsp_interior.rs
index 29b142f..2105d55 100644
--- a/src/map_builders/bsp_interior.rs
+++ b/src/map_builders/bsp_interior.rs
@@ -1,5 +1,4 @@
 use super::MapBuilder;
-use crate::map_builders::common::apply_room_to_map;
 use crate::spawner;
 use crate::{components::Position, Map, Rect, TileType, SHOW_MAPGEN_VISUALIZER};
 use rltk::RandomNumberGenerator;
@@ -22,7 +21,7 @@ impl MapBuilder for BspInteriorBuilder {
     }
 
     fn get_starting_position(&self) -> Position {
-        self.starting_position.clone()
+        self.starting_position
     }
 
     fn get_snapshot_history(&self) -> Vec<Map> {
@@ -91,6 +90,29 @@ impl BspInteriorBuilder {
             self.take_snapshot();
         }
 
+        // Now we sort the rooms
+        self.rooms.sort_by(|a, b| a.x1.cmp(&b.x1));
+
+        // Now we want corridors
+        for i in 0..self.rooms.len() - 1 {
+            let room = self.rooms[i];
+            let next_room = self.rooms[i + 1];
+            let start_x = room.x1 + (rng.roll_dice(1, i32::abs(room.x1 - room.x2)) - 1);
+            let start_y = room.y1 + (rng.roll_dice(1, i32::abs(room.y1 - room.y2) - 1));
+            let end_x =
+                next_room.x1 + (rng.roll_dice(1, i32::abs(next_room.x1 - next_room.x2)) - 1);
+            let end_y =
+                next_room.y1 + (rng.roll_dice(1, i32::abs(next_room.y1 - next_room.y2)) - 1);
+
+            self.draw_corridor(start_x, start_y, end_x, end_y);
+            self.take_snapshot();
+        }
+
+        // Don't forget the stairs
+        let stairs = self.rooms[self.rooms.len() - 1].center();
+        let stairs_idx = self.map.xy_idx(stairs.0, stairs.1);
+        self.map.tiles[stairs_idx] = TileType::DownStairs;
+
         let start = self.rooms[0].center();
         self.starting_position = start.into();
     }
@@ -137,4 +159,24 @@ impl BspInteriorBuilder {
             }
         }
     }
+
+    fn draw_corridor(&mut self, x1: i32, y1: i32, x2: i32, y2: i32) {
+        let mut x = x1;
+        let mut y = y1;
+
+        while x != x2 || y != y2 {
+            if x < x2 {
+                x += 1;
+            } else if x > x2 {
+                x -= 1;
+            } else if y < y2 {
+                y += 1;
+            } else if y > y2 {
+                y -= 1;
+            }
+
+            let idx = self.map.xy_idx(x, y);
+            self.map.tiles[idx] = TileType::Floor;
+        }
+    }
 }
diff --git a/src/map_builders/mod.rs b/src/map_builders/mod.rs
index 31a6138..f0b3a98 100644
--- a/src/map_builders/mod.rs
+++ b/src/map_builders/mod.rs
@@ -21,8 +21,9 @@ pub trait MapBuilder {
 
 pub fn random_builder(new_depth: i32) -> Box<dyn MapBuilder> {
     let mut rng = rltk::RandomNumberGenerator::new();
-    match rng.roll_dice(1, 2) {
+    match rng.roll_dice(1, 3) {
         1 => Box::new(BspDungeonBuilder::new(new_depth)),
+        2 => Box::new(BspInteriorBuilder::new(new_depth)),
         _ => Box::new(SimpleMapBuilder::new(new_depth)),
     }
 }