Basic working with ships partly implimented

lib/game/ship.rb

@@ -0,0 +1,146 @@
+# Nathan Hinton 30 Dec 2025
+# Ship file for the game
+
+require 'securerandom'
+
+# Load the ships into a constant:
+require 'yaml'
+SHIP_DATA = File.open('lib/game/ships.yaml', 'r') do |fi|
+  YAML.safe_load(fi.read())
+end
+
+class Ship
+
+  attr_reader :owner, :position
+
+  # Ships are built by a player so we should *always* know what player is
+  # owning a ship
+  #
+  # @param player [Player] The player who owns the ship
+  # @param position_x [Float] The starting x position of the ship.
+  # @param position_y [Float] The starting y position of the ship.
+  # @param position_z [Float] The starting z position of the ship.
+  def initialize(player, position_x, position_y, position_z, name)
+    @owner = player
+    @ship_id = SecureRandom.hex
+    @position = [position_x, position_y, position_z]
+    @target = @position
+    @speed = 1
+    @ship_info = validate_creation(name)
+  end
+
+  # Validates that the ship name exists and it is unlocked by the player (Has
+  # the right buildings and tech to actually create). This means that you might
+  # be able to start a ship however when it is 'finished' if a required
+  # building has been removed it will fail to finish properly. In this case the
+  # player resources should be refunded (with some lost) and the ship creation
+  # will raise an error.
+  def validate_creation(name)
+    ship = SHIP_DATA[name]
+    raise ShipError, "invalid ship name '#{name}'" if ship.nil?
+    # Validate that the owner has the correct tech:
+    ship['required_tech'].each do |tech_needed|
+      if !(@owner.researched_tech.include? tech_needed)
+        raise ShipError, "Player needs the tech of '#{tech_needed}'"
+      end
+    end
+    # Validate the buildings:
+    ship['required_buildings'].each do |building_needed|
+      if !(@owner.buildings.include? building_needed)
+        raise ShipError, "Player needs the building of '#{building_needed}' to build this ship"
+      end
+    end
+  end
+
+  # Teleport the ship to a given position. Really only should be used for admin
+  # stuff.
+  #
+  # @param position_x [Float] The new x position of the ship.
+  # @param position_y [Float] The new y position of the ship.
+  # @param position_z [Float] The new z position of the ship.
+  def teleport(position_x, position_y, position_z)
+    @position = [position_x, position_y, position_z]
+  end
+
+  # Sets the target position of a ship.
+  #
+  # @param position_x [Float] The new x position of the ship.
+  # @param position_y [Float] The new y position of the ship.
+  # @param position_z [Float] The new z position of the ship.
+  def move(position_x, position_y, position_z)
+    @target = [position_x, position_y, position_z]
+  end
+
+  # Contains the logic to move a ship
+  #
+  # @param delta_time [Float] The delta time elapsed in the game
+  def update(delta_time)
+    # Movement logic:
+    if @position == @target
+      # Do nothing
+    else
+      # Calculate the difference of the position and the target
+      x_dist = @target[0] - @position[0]
+      y_dist = @target[1] - @position[1]
+      z_dist = @target[2] - @position[2]
+      total_dist = Math.sqrt(x_dist**2 + y_dist**2 + z_dist**2)
+      speed = (@speed/total_dist) * delta_time
+
+      new_x = @position[0] + (x_dist * speed)
+      new_y = @position[1] + (y_dist * speed)
+      new_z = @position[2] + (z_dist * speed)
+
+      if x_dist > 0 # Going right
+        if new_x > @target[0]
+          new_x = @target[0]
+        end
+      elsif x_dist < 0 # Going left
+        if new_x < @target[0]
+          new_x = @target[0]
+        end
+      end
+
+      if y_dist > 0 # Going right
+        if new_y > @target[1]
+          new_y = @target[1]
+        end
+      elsif y_dist < 0 # Going left
+        if new_y < @target[1]
+          new_y = @target[1]
+        end
+      end
+
+      if z_dist > 0 # Going right
+        if new_z > @target[2]
+          new_z = @target[2]
+        end
+      elsif z_dist < 0 # Going left
+        if new_z < @target[2]
+          new_z = @target[2]
+        end
+      end
+      @position = [new_x, new_y, new_z]
+    end
+  end
+
+  # Save a player to a file
+  def save_to_file
+    File.open("game_data/#{self.planet_id}.save", 'wb') do |fi|
+      # Load resources for the player:
+      fi.write(Marshal.dump(self))
+    end
+    return self.planet_id
+  end
+
+  # Load a player from a file
+  def self.load_from_save(fname)
+    File.open("game_data/#{fname}_ship_.save", 'rb') do |fi|
+      # Load resources for the player:
+      Marshal.load(fi.read)
+    end
+  end
+end
+
+# Error class for ships
+class ShipError < StandardError
+end