Implementation of a command pattern example in c# for Mars Rover case.
- Case Description
- Case Analysis
- Class Diagrams
- Tools and Technologies Used
- License
A squad of robotic rovers are to be landed by NASA on a plateau on Mars. This plateau, which is curiously rectangular, must be navigated by the rovers so that their on board cameras can get a complete view of the surrounding terrain to send back to Earth.
A rover's position and location is represented by a combination of x and y co-ordinates and a letter representing one of the four cardinal compass points. The plateau is divided up into a grid to simplify navigation. An example position might be 0, 0, N, which means the rover is in the bottom left corner and facing North.
In order to control a rover, NASA sends a simple string of letters. The possible letters are 'L', 'R' and 'M'. 'L' and 'R' makes the rover spin 90 degrees left or right respectively, without moving from its current spot. 'M' means move forward one grid point, and maintain the same heading.
Assume that the square directly North from (x, y) is (x, y+1).
The first line of input is the upper-right coordinates of the plateau, the lower-left coordinates are assumed to be 0,0.
The rest of the input is information pertaining to the rovers that have been deployed. Each rover has two lines of input. The first line gives the rover's position, and the second line is a series of instructions telling the rover how to explore the plateau. The position is made up of two integers and a letter separated by spaces, corresponding to the x and y co-ordinates and the rover's orientation. Each rover will be finished sequentially, which means that the second rover won't start to move until the first one has finished moving.
The output for each rover should be its final co-ordinates and heading. Input and Output
Test Input: 5 5 1 2 N LMLMLMLMM 3 3 E MMRMMRMRRM
Expected Output: 1 3 N 5 1 E
There are three possible accepted types of command information lines which are;
This information lets us to find size of the plateu.
Which includes X and Y coordinates and direction(N,S,W,E).
Which might be Left,Right and Forward(L,R,M).
These information directs us to use command pattern on this case. We can use three commands types to do this;
Which sets height and width of the plateu.
Sets initial location and direction of the rover.
Updates location or direction of the rover.
Only recognized commands should be allowed(we can use regex). We should interpret command input lines into command objects. In general we can use dictionaries in order to avoid using switch case or if else statements. We can also delegates(Action or Func) in dictionaries as a return type to map command methods and movements.
- Visual Studio 2019
- .Net Core
- Autofac
- Moq
- Autofixture
- Fluent Assertions
- Coverlet
