[2016-03-28] Challenge #260 [Easy] Garage Door Opener

garage-door-opener.R

#
# [2016-03-28] Challenge #260 [Easy] Garage Door Opener
# https://www.reddit.com/r/dailyprogrammer/comments/4cb7eh/20160328_challenge_260_easy_garage_door_opener/
# Demo at http://www.r-fiddle.org/#/fiddle?id=83RtwcPP&version=1
#
# Kory Becker 4/3/2016
# http://primaryobjects.com
#

# Valid states and commands.
states <- c(CLOSED = 0, OPEN = 1, OPENING = 2, CLOSING = 3, STOPPED_WHILE_OPENING = 4, STOPPED_WHILE_CLOSING = 5, OPEN_BLOCKED = 6, EMERGENCY_OPENING = 7)
commands <- c(button_clicked = 0, cycle_complete = 1, block_detected = 2, block_cleared = 3)

input <- c(
  'button_clicked',
  'cycle_complete',
  'button_clicked',
  'button_clicked',
  'button_clicked',
  'button_clicked',
  'button_clicked',
  'cycle_complete'
)

inputBonus <- c(
  'button_clicked',
  'cycle_complete',
  'button_clicked',
  'block_detected',
  'button_clicked',
  'cycle_complete',
  'button_clicked',
  'block_cleared',
  'button_clicked',
  'cycle_complete'
)

click <- function(state) {
  if (state == states['CLOSED']) {
    state <- states['OPENING']
  }
  else if (state == states['OPEN']) {
    state <- states['CLOSING']
  }
  else if (state == states['CLOSING']) {
    state <- states['STOPPED_WHILE_CLOSING']
  }
  else if (state == states['OPENING']) {
    state <- states['STOPPED_WHILE_OPENING']
  }
  else if (state == states['STOPPED_WHILE_CLOSING']) {
    state <- states['OPENING']
  }
  else if (state == states['STOPPED_WHILE_OPENING']) {
    state <- states['CLOSING']
  }

  state
}

complete <- function(state) {
  if (state == states['CLOSING']) {
    state <- states['CLOSED']
  }
  else if (state == states['OPENING']) {
    state <- states['OPEN']
  }
  else if (state == states['EMERGENCY_OPENING']) {
    state <- states['OPEN_BLOCKED']
  }

  state
}

block <- function(state) {
  if (state == states['CLOSING']) {
    state <- states['EMERGENCY_OPENING']
  }

  state  
}

clear <- function(state) {
  if (state == states['OPEN_BLOCKED']) {
    state <- states['OPEN']
  }

  state
}

format <- function(command) {
  text <- NA

  if (command == names(commands['button_clicked'])) {
    text <- 'Button clicked.'
  }
  else if (command == names(commands['cycle_complete'])) {
    text <- 'Cycle complete.'
  }
  else if (command == names(commands['block_detected'])) {
    text <- 'Block detected!'
  }
  else if (command == names(commands['block_cleared'])) {
    text <- 'Block cleared.'
  }
  
  text
}

# Main loop.
run <- function(state, input) {
  # Print starting state.
  print(paste('Door:', names(state)))

  n <- sapply(input, function(command) {
    # Display command.
    print(paste('>', format(command)))
  
    # Transition to next state.
    if (commands[command] == commands['button_clicked']) {
      state <<- click(state)
    }
    else if (commands[command] == commands['cycle_complete']) {
      state <<- complete(state)
    }
    else if (commands[command] == commands['block_detected']) {
      state <<- block(state)
    }
    else if (commands[command] == commands['block_cleared']) {
      state <<- clear(state)
    }
    
    # Display current state.
    print(paste('Door:', names(state)))
  })
}

run(states['CLOSED'], input)
run(states['CLOSED'], inputBonus)

output.txt

> run(states['CLOSED'], input)
[1] "Door: CLOSED"
[1] "> Button clicked."
[1] "Door: OPENING"
[1] "> Cycle complete."
[1] "Door: OPEN"
[1] "> Button clicked."
[1] "Door: CLOSING"
[1] "> Button clicked."
[1] "Door: STOPPED_WHILE_CLOSING"
[1] "> Button clicked."
[1] "Door: OPENING"
[1] "> Button clicked."
[1] "Door: STOPPED_WHILE_OPENING"
[1] "> Button clicked."
[1] "Door: CLOSING"
[1] "> Cycle complete."
[1] "Door: CLOSED"

> run(states['CLOSED'], inputBonus)
[1] "Door: CLOSED"
[1] "> Button clicked."
[1] "Door: OPENING"
[1] "> Cycle complete."
[1] "Door: OPEN"
[1] "> Button clicked."
[1] "Door: CLOSING"
[1] "> Block detected!"
[1] "Door: EMERGENCY_OPENING"
[1] "> Button clicked."
[1] "Door: EMERGENCY_OPENING"
[1] "> Cycle complete."
[1] "Door: OPEN_BLOCKED"
[1] "> Button clicked."
[1] "Door: OPEN_BLOCKED"
[1] "> Block cleared."
[1] "Door: OPEN"
[1] "> Button clicked."
[1] "Door: CLOSING"
[1] "> Cycle complete."
[1] "Door: CLOSED"