woc

#!/bin/bash

### Tracker
# A command-line utility that tracks how you spend your time.
# @Author: David Duan
# @Date: 2018 Dec.

### Sample Usage:
# - tracker start <task-name>: start a new tracker.
# - tracker stop -m <comment>: stop the tracker and enter a descriptive message.
# - tracker add <task-name> <task-duration> -m <comment>

### More commands and flags will be supported in the future.
###################################################################################################
### Constants (you can modify these to suit your needs)

DIRECTORY=".tracker/"
INPUT_FILE="${DIRECTORY}input.txt"
OUTPUT_FILE="${DIRECTORY}output.txt"



### Helper Functions

error () {
  echo "[ERROR] $0: $1. Aborted" 1>&2
  exit 1
}


info () {
  echo "[INFO] $0: $1"
}


prompt() {
  echo "[PROMPT] $0: $1"
}


warning() {
  echo "[WARNING] $0: $1"
}


### Main Logic

start_handler () {

  task_name=$1
  start_time=$(date '+%H:%M:%S')
  info "Starting $task_name at ${start_time}."
  
  if [ -f $INPUT_FILE ]; then

    old_task_name=$(sed '1q;d' $INPUT_FILE)
    old_start_time=$(sed '2q;d' $INPUT_FILE)
    warning "You haven't stopped your last tracker ${old_task_name} (started at ${old_start_time}).
             To discard this record, enter N; to save the record, enter S."

    while true; do
      read response

      if [ ${response} == "N" ] || [ ${response} == "n" ]; then
        rm $INPUT_FILE
        break

      elif [ ${response} == "S" ] || [ ${response} == "s" ]; then
        echo "Enter a descriptive message:"
        read message
        stop_handler "-m" message
        break

      else
        echo "Unknown Input. Try again."

      fi
    done
  fi

  touch $INPUT_FILE
  echo $task_name >> $INPUT_FILE
  echo $start_time >> $INPUT_FILE
  info "Data written to $INPUT_FILE. GLHF!"
}


stop_handler () {

  flag=$1
  case $flag in
    -m)
      message=$2
      ;;
    *)
      error "unknown flag" 1>&2
  esac
  
  if [ -f ${INPUT_FILE} ]; then 

    task_name=$(sed '1q;d' ${INPUT_FILE})
    start_time=$(sed '2q;d' ${INPUT_FILE})

    end_time=$(date '+%H:%M:%S')
    duration=$(dateutils.ddiff ${start_time} ${end_time} -f '%M')

    info "You have invested ${duration} minutes on ${task_name}."
    
    today=$(date '+%D')
    echo ${today} ${task_name} ${duration} >> ${OUTPUT_FILE}
    echo ${message} >> ${OUTPUT_FILE}
    echo -en '\n' >> ${OUTPUT_FILE}

    rm ${INPUT_FILE}
    info "Data written to ${OUTPUT_FILE}. Take a break!"

  else 
    error "INPUT_FILE missing."

  fi
}


# Implementing later
add_handler() {
  :
}



### Main
mkdir -p $DIRECTORY
if [ ! -f $OUTPUT_FILE ]; then
  touch $OUTPUT_FILE
fi


if [ $# -lt 2 ]; then
  error "not enough arguments"
else
  if [ "$1" == "start" ]; 
  then

    if [ $# -ne 2 ]; then
      error "USAGE: tracker start <task_name>"
    fi

    start_handler $2          

  elif [ "$1" == "stop" ];
  then

    if [ $# -lt 3 ]; then
      error "USAGE: tracker stop -m <message>"
    fi

    stop_handler $2 "${@:3}" 

  elif [ "$1" == "add" ];
  then
    add_handler $2 $3 $4 $5   

  elif [ "$1" == "clean" ]  && [ "$2" == "-f" ];
  then
    rm $INPUT_FILE > /dev/null
    info "Removed INPUT_FILE."

  elif [ "$1" == "hard-clean" ] && [ "$2" == "-f" ];
  then
    rm $INPUT_FILE $OUTPUT_FILE > /dev/null
    info "Removed both INPUT_FILE and OUTPUT_FILE."

  fi

fi