#!/usr/bin/env bash
:<<'__comments__'
    Name: list-transactions-for
   Usage: see show_usage()
Synopsis: Extract, sort, format and print a list of postings from $LEDGER_FILE.
   Notes: See style guide at https://google.github.io/styleguide/shell.xml
  Author: G. D. LaBossiere, Xview Solutions Inc. <code@XviewSolutions.com>
 Version: 1.0.0 <http://semver.org>
 Created: 2019-04-07 (version 1.0.0)
Modified: 2019-05-01
 License: GNU GPL v3 <http://www.gnu.org/licenses/gpl-3.0.txt>
__comments__
#------------------------------------------------------------------------------
#  constants
#------------------------------------------------------------------------------
#  export ledger environment vars to set options which must otherwise be set on
#+ the command line; see 'man 1 ledger'
export LEDGER_DATE_FORMAT="%d %b %Y"
export LEDGER_FILE=""
#  ledger account regexes to search for query_customer() and query_supplier();
#+ ledger regex searches are case-insensitive; modify the values of these
#+ constants to match the naming convention used in your chart of accounts
QUERY_CUSTOMER_ACCOUNTS="(receivable or deferred)"
QUERY_SUPPLIER_ACCOUNTS="(Assets or Expense) and not (Bank or Taxes)"
#------------------------------------------------------------------------------
#  error codes
#------------------------------------------------------------------------------
ERROR_0="Program terminated normally"
ERROR_10="Requires bash 4.2+"
ERROR_15="Missing required program(s)"
ERROR_16="Missing required function(s)"
ERROR_18="Bad or missing required parameter(s)"
ERROR_22="Required file(s) not found"
#------------------------------------------------------------------------------
#  variables
#-------------------------------------------------------------------------------
argList=""
beginDate=""
endDate=""
errFuncName=""
exitMessage=""
ledgerOpts=""
pattern1=""
pattern2=""
queryType=""
#------------------------------------------------------------------------------
#  functions
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: check_bash
 Synopsis: Check for supported bash versions
Arguments: ---
 Requires: bash 4.2+
  Returns: 0 on success; $errFuncName and exit 10 on error.
    Calls: ---
__comments__
check_bash() {
  errFuncName="$FUNCNAME"
  [[ ${BASH_VERSINFO[0]} -eq 4 && ${BASH_VERSINFO[1]} -ge 2 ]] || \
    [[ ${BASH_VERSINFO[0]} -gt 4 ]] || exit 10
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: check_dates
 Synopsis: If $beginDate and $endDate are set verify the first is earlier.
Arguments: ---
 Requires: ---
  Returns: 0 on success; $errFuncName, $exitMessage and exit 15 or 18 on error.
    Calls: ---
__comments__
check_dates() {
  errFuncName="${FUNCNAME}"
  type -p date &>/dev/null || exit 15
  [[ $beginDate ]] && {
    date -d "$beginDate" &>/dev/null || {
      exitMessage="'--begin' is not followed by a valid date"
      exit 18
    }
  }
  [[ $endDate ]] && {
    date -d "$endDate" &>/dev/null || {
      exitMessage="'--end' is not followed by a valid date"
      exit 18
    }
  }
  [[ $beginDate && $endDate ]] && {
    [[ $(date -d "$beginDate" +%s) -le $(date -d "$endDate" +%s) ]] || {
      exitMessage="'--begin' date must be earlier than '--end' date"
      exit 18
    }
  }
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: check_params
 Synopsis: If $1 contains 'acc[ount]' or 'cus[tomer]' or 'sup[plier]' assign
           "$1" to $queryType; if $queryType is set and does not have value
           'acc[ount]' assign "$@" to $pattern1; if $queryType has value
           'acc[ount]' and $pattern1 is not set assign "$@" to $pattern1; if
           $queryType has value 'acc[ount]' and $pattern1 is set assign "$@" to
           $pattern2.
Arguments: (required) $1=TYPE, $2=PATTERN; (optional) $3=PATTERN
 Requires: ledger
  Returns: 0 on success; $errFuncName, $exitMessage and exit 15 or 18 on error.
    Calls: ---
__comments__
check_params() {
  errFuncName="$FUNCNAME"
  type -p ledger &>/dev/null || exit 15
  [[ $queryType ]] || {
#  need minimum 3 alphanum chars to match a valid $queryType
    [[ ${1,,} =~ ^acc[ount]*$|^cus[tomer]*$|^sup[plier]*$ ]] || {
      exitMessage="Valid TYPE values are: 'acc[ount]' or 'cus[tomer]' or"
      exitMessage="${exitMessage} sup[plier]'"
      exit 18
    }
    queryType="${1,,}"
    return 0
  }
#  the value for $pattern1 or $pattern2 may be a string (e.g. 'abcdefg') or a
#+ regular expression (e.g. '^abcdefg$' or '/abcdefg/')
  [[ $queryType && $pattern1 ]] || {
    pattern1="$@"
    return 0
  }
  [[ $queryType && $pattern1 && $pattern2 ]] || pattern2="$@"
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: check_required
 Synopsis: Verify all required tools/utilities are available on this host.
Arguments: ---
 Requires: sed, sort, tr
  Returns: 0 on success; $errFuncName, $exitMessage and exit 15 or 22 on error.
    Calls: ---
__comments__
check_required() {
  errFuncName="$FUNCNAME"
  type -p sed sort tr &>/dev/null || exit 15
  local each missing required
#  explanation of sed commands:
#+ sed -e "s/#.*$//" -e "/^$/d" ==> exclude commented or blank lines
#+ sed -ne "/ type /p" ==> select only lines containing ' type '
#+ ${0} ==> this file
#+ sed -e "s/.*type \-*p*P*\(.*\).\+>.*/\1/" ==> extract strings between
#+ 'type -p' and '?>' (i.e. save the arguments passed to 'type' but exclude
#+ everything from and after the first char before a '>' redirection symbol)
#+ sed -e "s/\$.\+ //g" ==> delete any space-terminated strings that start with
#+ a '$' dollar symbol (i.e. unexpanded vars)
#+ sed -e "s/[^0-9a-zA-Z_ -]//g" ==> delete chars not allowed in program names
  required=($(sed -e "s/#.*$//" -e "/^$/d" -ne "/ type /p" "${0}" | \
    sed -e "s/.*type \-*p*P*\(.*\).\+>.*/\1/" -e "s/\$.\+ //g" \
    -e "s/[^0-9a-zA-Z_ -]//g"))
#  explanation of commands:
#+ printf "%s\n" "${required[@]}" ==> output each array element
#+ sort -u ==> remove duplicate names
#+ tr '\n' ' ' ==> replace newlines with spaces (i.e. convert to a string)
#+ tr -s ' ' ==> squeeze spaces (i.e. leave a single space between names)
  required="$(printf "%s\n" "${required[@]}" | sort -u | tr '\n' ' ' | \
    tr -s ' ' )"
  for each in ${required}; do
    type -p "${each}" &>/dev/null || missing="${missing} ${each}"
  done
  exitMessage="Required program(s) not found: ${missing}"
  [[ $missing ]] &&  exit 15
  exitMessage="Cannot read LEDGER_FILE '$LEDGER_FILE' or the file is undefined"
  [[ -r $LEDGER_FILE ]] || exit 22
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: exit_message
 Synopsis: If attached to a tty and $? is non-zero, display a message; exit
           with value $?; the first statement to appear in main() must be:
           trap exit_message EXIT
Arguments: ---
 Requires: ---
  Returns: exit $?
    Calls: ---
__comments__
exit_message() {
  local errNum="$?"
  local errTxt="ERROR_${errNum}"
  local errMsg="Error ${errNum}: No description available"
  [[ ${!errTxt} ]] && errMsg="Error ${errNum}: ${!errTxt}"
  [[ ${errFuncName} ]] && errMsg="${errFuncName}: ${errMsg}"
  errMsg="${0##*/}: ${errMsg}"
  [[ -t 1 && $errNum -ne 0 ]] && {
    [[ $exitMessage ]] && printf "%b\n" "${exitMessage}"
    printf "%s\n" "${errMsg}"
  }
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: parse_command_line
 Synopsis: Parse the command line arguments.
Arguments: $queryType $pattern1 [$pattern2] [--begin DATE] [--end DATE]
           [--effective] [--basis|--cost]
 Requires: ---
  Returns: $beginDate, $endDate, $ledgerOpts; 0 in all cases.
    Calls: check_dates, check_params, show_usage
__comments__
parse_command_line() {
  errFuncName="$FUNCNAME"
  local arg=0 args=("${argList[@]}")
  while [[ $arg -lt ${#args[@]} ]]; do
    case "${args[$arg]}" in
      --basis|--cost)
        [[ $ledgerOpts =~ '--basis'|'--cost' ]] || \
          ledgerOpts="${ledgerOpts} ${args[$arg]}"
        ((++arg))
      ;;
      --effective)
        [[ $ledgerOpts =~ '--effective' ]] || \
          ledgerOpts="${ledgerOpts} ${args[$arg]}"
        ((++arg))
      ;;
      --begin)
        [[ $beginDate ]] || {
          beginDate="${args[$((${arg}+1))]}"
          check_dates
          ledgerOpts="${ledgerOpts} --begin ${beginDate}"
          ((++arg))
        }
        ((++arg))
      ;;
      --end)
        [[ $endDate ]] || {
          endDate="${args[$((${arg}+1))]}"
          check_dates
          ledgerOpts="${ledgerOpts} --end ${endDate}"
          ((++arg))
        }
        ((++arg))
      ;;
      -*)
        show_usage
      ;;
      *)
#  do NOT quote the argument; check_params() will parse the command line
        check_params ${args[$arg]}
        ((++arg))
      ;;
    esac
  done
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: query_account
 Synopsis: Create the search patterns and output formats associated with the
           $queryType value 'acc[ount]'; search $LEDGER_FILE; generate and
           print the results.
Arguments: ---
 Requires: cut, ledger, sed, sort, tr
  Returns: 0 on success; $errFuncName, $exitMessage and exit 15 or 18 on error.
    Calls: ---
__comments__
query_account() {
  [[ ${queryType,,} =~ ^acc[ount]*$ ]] || return 0
  errFuncName="$FUNCNAME"
  type -p cut ledger sed sort tr &>/dev/null || exit 15
  local account accounts dashes date format header search
  date="Date"
  [[ $ledgerOpts =~ '--effective' ]] || date="Actual date"
  header="Account names containing '${pattern1^^}'"
  [[ $pattern1 =~ [0-9a-zA-Z] ]] || header="All accounts"
  printf "\n"
  [[ $ledgerOpts =~ '--effective' ]] || printf "%13s"
  printf "%13s%s" "" "${header}"
  [[ $pattern2 ]] && {
    printf " %s" "with transactions containing '${pattern2^^}'"
    search="and ( %(payee($pattern2)) or %(note($pattern2))"
    search="${search} or %(code($pattern2)) )"
  }
  [[ $beginDate ]] && printf " %s" "starting at ${beginDate}"
  [[ $endDate ]] && printf " %s" "up to ${endDate}"
  printf "\n\n"
  format="%A\n"
#  each $account in ${accounts[@]} matches $pattern1
  readarray -t accounts < <(ledger -F "${format}" reg ${pattern1} | sort -u)
#  list all transactions in $account if $pattern2 is not set, else list only
#+ transactions matching $pattern2; skip $account if no transactions match
  for account in "${accounts[@]}"; do
#  must replace spaces in $account with '.' because when bash expands the value
#+ of $account ledger will not escape the spaces so regex parsing is broken
    [[ $(ledger ${ledgerOpts} register ${account// /.} ${search}) ]] && {
      printf -v dashes "%154s"
      [[ $ledgerOpts =~ '--effective' ]] || printf -v dashes "%167s"
      dashes="${dashes// /-}"
      printf "%s\n\n\n" "${dashes}"
      [[ $ledgerOpts =~ '--effective' ]] || printf "%-11s%2s" "Posted date" ""
      printf "%-11s%2s%-107s%2s%15s%2s%15s\n" "${date}" "" \
        "${account//:/ ==> }" "" "Amount" "" "Balance"
      printf -v dashes "%107s"
      dashes="${dashes// /-}"
      [[ $ledgerOpts =~ '--effective' ]] || printf "%s%2s" "-----------" ""
      printf "%s%2s%s%2s%s%2s%s\n" "-----------" "" "${dashes}" "" \
        "---------------" "" "---------------"
      format="%d %-20.20C %-30.30P  %-55.55N  %15.15t  %15T\r"
      [[ $ledgerOpts =~ '--effective' ]] || {
        ledger ${ledgerOpts} -F "${format}" -S 'date' register \
          ${account// /.} ${search} | tr '\n' '\v' | tr '\r' '\n' | \
          sed -e "s/=/  /g; s/\xB/  /g; s/[()]/ /g;"
      }
      [[ $ledgerOpts =~ '--effective' ]] && {
        ledger ${ledgerOpts} -F "${format}" -S 'date' register \
          ${account// /.} ${search} | tr '\n' '\v' | tr '\r' '\n' | \
          cut -d'=' -f2 | sed -e "s/\xB/  /g; s/[()]/ /g;"
      }
   }
  done
  printf -v dashes "%154s"
  [[ $ledgerOpts =~ '--effective' ]] || printf -v dashes "%167s"
  dashes="${dashes// /-}"
  printf "%s\n" "${dashes}"
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: query_customer
 Synopsis: Create the search patterns and output formats associated with the
           $queryType value 'cus[tomer]'; search $LEDGER_FILE; generate and
           print the results.
Arguments: ---
 Requires: cut, ledger, sed, tr
  Returns: 0 on success; $errFuncName, $exitMessage and exit 15 or 18 on error.
    Calls: ---
__comments__
query_customer() {
  [[ ${queryType,,} =~ ^cus[tomer]*$ ]] || return 0
  errFuncName="$FUNCNAME"
  type -p cut ledger sed tr &>/dev/null || exit 15
  local dashes date format
  date="Date"
  [[ $ledgerOpts =~ '--effective' ]] || date="Actual date"
  printf -v dashes "%65s"
  dashes="${dashes// /-}"
  printf "\n"
  [[ $ledgerOpts =~ '--effective' ]] || printf "%-11s%2s" "Posted date" ""
  printf "%-11s%2s%-65s%2s%15s%2s%15s\n" "${date}" "" \
    "Transactions for ${pattern1^^}" "" "Amount" "" "Balance"
  [[ $ledgerOpts =~ '--effective' ]] || printf "%s%2s"  "-----------" ""
  printf "%s%2s%s%2s%s%2s%s\n" "-----------" "" "${dashes}" "" \
    "---------------" "" "---------------"
  format="%d %-20.20C %-45.45N  %15.15t  %15T\r"
  [[ $ledgerOpts =~ '--effective' ]] || {
    ledger ${ledgerOpts} -F "${format}" -S 'date' register \
      ${QUERY_CUSTOMER_ACCOUNTS} and @${pattern1} | tr '\n' '\v' | \
      tr '\r' '\n' | sed -e "s/=/  /g; s/\xB/  /g; s/[()]/ /g;"
    return 0
  }
  ledger ${ledgerOpts} -F "${format}" -S 'date' register \
    ${QUERY_CUSTOMER_ACCOUNTS} and @${pattern1} | tr '\n' '\v' | \
    tr '\r' '\n' | cut -d'=' -f2 | sed -e "s/\xB/  /g; s/[()]/ /g;"
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: query_supplier
 Synopsis: Create the search patterns and output formats associated with the
           $queryType value 'sup[plier]'; search $LEDGER_FILE; generate and
           print the results.
Arguments: ---
 Requires: cut, ledger, sed, tr
  Returns: 0 on success; $errFuncName, $exitMessage and exit 15 or 18 on error.
    Calls: ---
__comments__
query_supplier() {
  [[ ${queryType,,} =~ ^sup[plier]*$ ]] || return 0
  errFuncName="$FUNCNAME"
  type -p cut ledger sed tr &>/dev/null || exit 15
  local dashes date format
  date="Date"
  [[ $ledgerOpts =~ '--effective' ]] || date="Actual date"
  printf -v dashes "%107s"
  dashes="${dashes// /-}"
  printf "\n"
  [[ $ledgerOpts =~ '--effective' ]] || printf "%-11s%2s" "Posted date" ""
  printf "%-11s%2s%-107s%2s%15s%2s%15s\n" "${date}" "" \
    "Transactions for ${pattern1^^}" "" "Amount" "" "Balance"
  [[ $ledgerOpts =~ '--effective' ]] || printf "%s%2s"  "-----------" ""
  printf "%s%2s%s%2s%s%2s%s\n" "-----------" "" "${dashes}" "" \
    "---------------" "" "---------------"
  format="%d %-20.20C %-30.30P  %-55.55N  %15.15t  %15T\r"
  [[ $ledgerOpts =~ '--effective' ]] || {
    ledger ${ledgerOpts} -F "${format}" -S 'payee,date' register \
      ${QUERY_SUPPLIER_ACCOUNTS} and @${pattern1} | tr '\n' '\v' | \
      tr '\r' '\n' | sed -e "s/=/  /g; s/\xB/  /g; s/[()]/ /g;"
    return 0
  }
  ledger ${ledgerOpts} -F "${format}" -S 'payee,date' register \
    ${QUERY_SUPPLIER_ACCOUNTS} and @${pattern1} | tr '\n' '\v' | \
    tr '\r' '\n' | cut -d'=' -f2 | sed -e "s/\xB/  /g; s/[()]/ /g;"
  return 0
}
#------------------------------------------------------------------------------
:<<'__comments__'
     Name: show_usage
 Synopsis: Display program usage if attached to a tty.
Arguments: ---
 Requires: ---
  Returns: Exit 0 in all cases.
    Calls: ---
__comments__
show_usage() {
  [[ -t 1 ]] || exit 0
  printf "%b" "
-------------------------------------------------------------------------------

  Usage: ${0##*/} TYPE 'PATTERN 1' ['PATTERN 2'] [OPTIONS]

         Extract, sort, format and display records from \$LEDGER_FILE where
         TYPE must be one of: acc[ount], cus[tomer] or sup[plier] and both
         'PATTERN 1' and 'PATTERN 2' are quoted strings or regular expressions.
         All of them are case-insensitive.

         If TYPE is acc[ount] then 'PATTERN 1' must specify the ledger accounts
         to list. Use '.' to list all accounts. The records listed may be
         optionally limited to those containing 'PATTERN 2'. Use a period '.'
         not a space ' ' in a quoted string.

         If TYPE is cus[tomer] or sup[plier] 'PATTERN 2' is ignored.

Options: --begin DATE
         Exclude records before DATE.

         --end DATE
         Exclude records after DATE.

         --effective
         Exclude records by their effective date not their posting date.

         --basis, --cost
         Display all monetary amounts converted to base currency.

         Unrecognized options cause this message to be displayed.

-------------------------------------------------------------------------------

"
  exit 0
}
#------------------------------------------------------------------------------
#  main
#------------------------------------------------------------------------------
main() {
  trap exit_message EXIT
  argList=("$@")
  declare -F check_bash check_required check_dates check_params exit_message \
    parse_command_line query_account query_customer query_supplier show_usage \
    &>/dev/null || exit 16
  check_bash
  check_required
  parse_command_line
  query_account
  query_customer
  query_supplier
  exit 0
}
#------------------------------------------------------------------------------
#  run program
#------------------------------------------------------------------------------
main "$@"