#!/bin/sh

# ---------- constants ----------
PRINTF_SAME_LINE=1

LOG_FILE_SIZE_MB="bs=1024 count=10k"
LOG_FILE_SIZE_KB="bs=1024 count=100"

PARTITION_SDCARD="/media/sd-card"
PARTITION_CONFIG="/var/configurations"

OPT_HELP="-h"
OPT_TYPE="-t"
OPT_YEAR="-y"
OPT_PCNT="-%"
OPT_CRLF="-r"

LOG_DAY_MIN=1
LOG_DAY_MAX=28

LOG_MONTH_MIN=1
LOG_MONTH_MAX=12

LOG_YEAR_MIN=2000
LOG_YEAR_MAX=$(date +%Y)

CUR_YEAR_MAX=$LOG_YEAR_MAX
CUR_MONTH_MAX=$(date +%m)
CUR_DAY_MAX=$(date +%d)
CUR_HOUR="00"
CUR_MINUTE="00"

LOG_PCNT_MIN=5
LOG_PCNT_MAX=95

LOG_TYPE_SIZE_LOG=$LOG_FILE_SIZE_MB
LOG_TYPE_NAME_LOG="log"
LOG_TYPE_PART_LOG=$PARTITION_SDCARD
LOG_TYPE_PATH_LOG="log"
LOG_TYPE_EXTN_LOG="log"
LOG_TYPE_EXTR_LOG=""
LOG_TYPE_PCNT_LOG=85

LOG_TYPE_SIZE_ERR=$LOG_FILE_SIZE_MB
LOG_TYPE_NAME_ERR="service"
LOG_TYPE_PART_ERR=$PARTITION_SDCARD
LOG_TYPE_PATH_ERR="service"
LOG_TYPE_EXTN_ERR="err"
LOG_TYPE_EXTR_ERR=""
LOG_TYPE_PCNT_ERR=85

LOG_TYPE_SIZE_CLD=$LOG_FILE_SIZE_MB
LOG_TYPE_NAME_CLD="cloudsync"
LOG_TYPE_PART_CLD=$PARTITION_SDCARD
LOG_TYPE_PATH_CLD="cloudsync/log"
LOG_TYPE_EXTN_CLD="log"
LOG_TYPE_EXTR_CLD=""
LOG_TYPE_PCNT_CLD=85

LOG_TYPE_SIZE_TXR=$LOG_FILE_SIZE_KB
LOG_TYPE_NAME_TXR="treatment"
LOG_TYPE_PART_TXR=$PARTITION_CONFIG
LOG_TYPE_PATH_TXR="treatment"
LOG_TYPE_EXTN_TXR="txr"
LOG_TYPE_EXTR_TXR=".p"
LOG_TYPE_PCNT_TXR=80

# ---------- variables ----------
paramlist="$@"

part_size=0
part_free_s=0
part_used_s=0
part_free_p=0
part_used_p=0

path_used_s=0
path_used_p=0
path_free_p=0

logs_used_p=0
logs_free_p=0


log_year=$LOG_YEAR_MIN
log_size=""
log_type=""
log_partition=""
log_folder=""
log_extension=""
log_extension_extra=""

cur_day=0
cur_month=$LOG_MONTH_MIN
cur_year=$LOG_YEAR_MIN
cur_hour=$CUR_HOUR
cur_minute=$CUR_MINUTE
cur_timestamp=""
cur_fullName=""
cur_fullPathName=""
cur_counter=0
cur_doGenerate=1

cur_DD=""
cur_MM=""
cur_YY=""


# ---------- functions ----------
function error() {
  echo "ERROR: $1"
  exit 1
}

function isNumeric() {
  [[ $1 =~ ^[0-9]+$ ]] && return 0 || return 1
}

function addLeadingZero() {
  if (( $1 < 10 )); then
    echo "0$1"
  else 
    echo "$1"
  fi
}

function displayHelp() {
  local format="%s %-15s %s %s\n"
  echo
  echo "$0 [-h | options]"
  echo " -h    display the current help"
  echo " $OPT_TYPE log type to test"
  echo " $OPT_YEAR starting year of the file creation date"
  echo " $OPT_PCNT the optional max percentage of the partition to fill"
  echo " $OPT_CRLF the optional option to print each status on next line"
  echo
  echo "Usage example"
  printf "$format" "$0" "$OPT_TYPE$LOG_TYPE_NAME_LOG" "[-y2000]" "[-%85] [-r]"
  printf "$format" "$0" "$OPT_TYPE$LOG_TYPE_NAME_ERR" "[-y2000]" "[-%85] [-r]"
  printf "$format" "$0" "$OPT_TYPE$LOG_TYPE_NAME_CLD" "[-y2000]" "[-%85] [-r]"
  printf "$format" "$0" "$OPT_TYPE$LOG_TYPE_NAME_TXR" "[-y2000]" "[-%30] [-r]"
  
  exit 0
}

function checkParams() {
  # check $1
  for param in $paramlist; do
    case "$param" in
      $OPT_TYPE$LOG_TYPE_NAME_LOG)
        log_type=$LOG_TYPE_NAME_LOG
        log_size=$LOG_TYPE_SIZE_LOG
        log_partition=$LOG_TYPE_PART_LOG
        log_folder=$LOG_TYPE_PATH_LOG
        log_extension=$LOG_TYPE_EXTN_LOG
        log_extension_extra=$LOG_TYPE_EXTR_LOG
        logs_used_p=$LOG_TYPE_PCNT_LOG
      ;;
      
      $OPT_TYPE$LOG_TYPE_NAME_ERR)
        log_type=$LOG_TYPE_NAME_ERR
        log_size=$LOG_TYPE_SIZE_ERR
        log_partition=$LOG_TYPE_PART_ERR
        log_folder=$LOG_TYPE_PATH_ERR
        log_extension=$LOG_TYPE_EXTN_ERR
        log_extension_extra=$LOG_TYPE_EXTR_ERR
        logs_used_p=$LOG_TYPE_PCNT_ERR
      ;;
      
      $OPT_TYPE$LOG_TYPE_NAME_CLD)
        log_type=$LOG_TYPE_NAME_CLD
        log_size=$LOG_TYPE_SIZE_CLD
        log_partition=$LOG_TYPE_PART_CLD
        log_folder=$LOG_TYPE_PATH_CLD
        log_extension=$LOG_TYPE_EXTN_CLD
        log_extension_extra=$LOG_TYPE_EXTR_CLD
        logs_used_p=$LOG_TYPE_PCNT_CLD
      ;;
      
      $OPT_TYPE$LOG_TYPE_NAME_TXR)
        log_type=$LOG_TYPE_NAME_TXR
        log_size=$LOG_TYPE_SIZE_TXR
        log_partition=$LOG_TYPE_PART_TXR
        log_folder=$LOG_TYPE_PATH_TXR
        log_extension=$LOG_TYPE_EXTN_TXR
        log_extension_extra=$LOG_TYPE_EXTR_TXR
        logs_used_p=$LOG_TYPE_PCNT_TXR
      ;;
      
      $OPT_PCNT*)
        logs_used_p="$param"
        logs_used_p="${logs_used_p:${#OPT_PCNT}}"
      ;;
      
      $OPT_YEAR*)
        log_year="$param"
        log_year="${log_year:${#OPT_YEAR}}"
      ;;
      
      $OPT_CRLF)
        PRINTF_SAME_LINE=0
      ;;

      $OPT_HELP)
        displayHelp
      ;;
 
      *)
        error "invalid option '$param'"
      ;;
    esac
  done

  # check the type
  if [ -z $log_type ]; then
    error "log type is missing"
  fi

  # check year
  if ! isNumeric $log_year; then
    error "invalid log start year: '$log_year'"
  fi

  if (( $log_year < $LOG_YEAR_MIN || $LOG_YEAR_MAX < $log_year )); then
    error "invalid log year range: '$log_year' [$LOG_YEAR_MIN, $LOG_YEAR_MAX]"
  fi
  cur_year=$log_year

  # check percent
  if ! isNumeric $logs_used_p; then
    error "invalid log fill usage percent: '$log_year'"
  fi
  logs_free_p=$(( 100 - $logs_used_p ))

  if (( $logs_used_p < $LOG_PCNT_MIN || $LOG_PCNT_MAX < $logs_used_p )); then
    error "invalid log fill usage percent range: '$logs_used_p' [$LOG_PCNT_MIN, $LOG_PCNT_MAX]"
  fi

  echo "log type '$log_type'"
  echo "location '$log_partition/$log_folder'"
  echo "start year from '$log_year'"
  echo "stops at '$logs_used_p%' total percent used"
}

function incDate() {
  cur_day=$(( $cur_day + 1 ))
  if (( $cur_day > $LOG_DAY_MAX )); then
    cur_day=$LOG_DAY_MIN
    cur_month=$(( $cur_month + 1 ))
  fi

  if (( $cur_month > $LOG_MONTH_MAX )); then    
    cur_month=$LOG_MONTH_MIN
    cur_year=$(( $cur_year + 1 ))
  fi
  
  # if (( $cur_year >= $LOG_YEAR_MAX )); then
  #   #TODO: the fact that we can pass today date is not checked  
  # fi

  
  cur_DD=$(addLeadingZero $cur_day)
  cur_MM=$(addLeadingZero $cur_month)
  cur_YY="$cur_year"
}

#    1              2         3      4      5       6 
#Filesystem     1K-blocks   Used Available Use% Mounted on
#/dev/mmcblk1p1  15247276 591392  13861644   5% /media/sd-card
function getPartitionSize() {
  part_size=$(df $log_partition | awk 'NR==2 {print $2}')
}

function getSpacePercents() {
  part_used_s=$(df $log_partition | awk 'NR==2 {print $3}')
  part_free_s=$(df $log_partition | awk 'NR==2 {print $4}')
  part_used_p=$(df $log_partition | awk 'NR==2 {print $5}')
 #part_used_p=$(( $part_used_s * 100 / $part_size )) # this percentage cannot be calculated from df and it is not accurate.
  part_free_p=$(( $part_free_s * 100 / $part_size ))
  
  path_used_s=$(du $log_partition/$log_folder 2>/dev/null | tail -n 1 | cut -f1)
  path_used_p=$(( $path_used_s * 100 / $part_size ))
  path_free_p=$(( 100 - $path_used_p ))
}

function generateLog() {
  dd if=/dev/urandom of="$cur_fullPathName" $log_size status=none
  touch -t $log_timestamp $cur_fullPathName
}

function printStatus() {
  local format="| %-10s | %-50s | Used:%5s | Total Used:%5s |\n"
  local message=""
  if (( cur_doGenerate == 0 )); then
    message="$log_type log generation stopped [CTRL+C to exit]"
  else
    message=$cur_fullPathName
  fi
  
  if (( $PRINTF_SAME_LINE == 1 )); then
    format="\r| %-10s | %-50s | Used:%5s | Total Used:%5s |"
  fi
  
  printf "$format" \
        "$cur_counter" "$message" "$path_used_p%" "$part_used_p"
}

function setTimestamp() {
  log_timestamp="$cur_YY$cur_MM$cur_DD$cur_hour$cur_minute"
}

function setFullPathName() {
  local extra=""
  if (( $cur_counter % 2 == 0 )); then
    extra="$log_extension_extra"
  fi
  cur_fullName="$cur_YY-$cur_MM-$cur_DD.$log_extension$extra"
  cur_fullPathName="$log_partition/$log_folder/$cur_fullName"
}

function generate() {
  
  getPartitionSize
  
  while true; do
    getSpacePercents
    
    if (( $cur_doGenerate == 1 )); then
      if (( $part_free_p < $logs_free_p ));then
        cur_doGenerate=0
        echo
      fi
    fi
  
    if (( $cur_doGenerate == 0 )); then
      printStatus
    else
      cur_counter=$(( cur_counter + 1 ))
      incDate
      setTimestamp
      setFullPathName
      generateLog
      printStatus      
    fi
  done
  echo "Done total files added $cur_counter"
}

function main() {
  checkParams "$@"
  generate    "$@"
}

# start the script
main "$@"