#!/usr/bin/env bash
set -e

# Just stream the TAP output (sans extended syntax) if tput is missing
command -v tput >/dev/null || exec grep -v "^begin "

setglobal header_pattern = ''[0-9]+\.\.[0-9]+''
env IFS= read -r header

if [[ "$header" =~ $header_pattern ]] {
  setglobal count = $(header:3)
  setglobal index = '0'
  setglobal failures = '0'
  setglobal skipped = '0'
  setglobal name = ''""
  setglobal count_column_width = $shExpr(' ${#count} * 2 + 2 ')
} else {
  # If the first line isn't a TAP plan, print it and pass the rest through
  printf "%s\n" $header
  exec cat
}

proc update_screen_width {
  setglobal screen_width = $[tput cols]
  setglobal count_column_left = $shExpr(' $screen_width - $count_column_width ')
}

trap update_screen_width WINCH
update_screen_width

proc begin {
  go_to_column 0
  printf_with_truncation $shExpr(' $count_column_left - 1 ') "   %s" $name
  clear_to_end_of_line
  go_to_column $count_column_left
  printf "%$(#count)s/$(count)" $index
  go_to_column 1
}

proc pass {
  go_to_column 0
  printf " ✓ %s" $name
  advance
}

proc skip {
  var reason = $1
  test -z $reason || set reason = "": $reason""
  go_to_column 0
  printf " - %s (skipped%s)" $name $reason
  advance
}

proc fail {
  go_to_column 0
  set_color 1 bold
  printf " ✗ %s" $name
  advance
}

proc log {
  set_color 1
  printf "   %s\n" $1
  clear_color
}

proc summary {
  printf "\n%d test%s" $count $[plural $count]

  printf ", %d failure%s" $failures $[plural $failures]

  if test $skipped -gt 0 {
    printf ", %d skipped" $skipped
  }

  printf "\n"
}

proc printf_with_truncation {
  var width = $1
  shift
  var string = $[printf @Argv]

  if test $(#string) -gt $width {
    printf "%s..." $(string:0:$(( $width - 4 )))
  } else {
    printf "%s" $string
  }
}

proc go_to_column {
  var column = $1
  printf "\x1B[%dG" $shExpr(' $column + 1 ')
}

proc clear_to_end_of_line {
  printf "\x1B[K"
}

proc advance {
  clear_to_end_of_line
  echo
  clear_color
}

proc set_color {
  var color = $1
  var weight = $2
  printf "\x1B[%d;%dm" $shExpr(' 30 + $color ') $[ test $weight = "bold" && echo 1 || echo 22]
}

proc clear_color {
  printf "\x1B[0m"
}

proc plural {
  test $1 -eq 1 || echo "s"
}

setglobal _buffer = ''""

proc buffer {
  setglobal _buffer = ""$(_buffer)$[@Argv]""
}

proc flush {
  printf "%s" $_buffer
  setglobal _buffer = ''""
}

proc finish {
  flush
  printf "\n"
}

trap finish EXIT

while env IFS= read -r line {
  match $line {
  with "begin "* 
    let index+=1
    setglobal name = $(line#* $index )
    buffer begin
    flush
    
  with "ok "* 
    setglobal skip_expr = ""ok $index # skip (\(([^)]*)\))?""
    if [[ "$line" =~ $skip_expr ]] {
      let skipped+=1
      buffer skip $(BASH_REMATCH[2])
    } else {
      buffer pass
    }
    
  with "not ok "* 
    let failures+=1
    buffer fail
    
  with "# "* 
    buffer log $(line:2)
    
  }
}

buffer summary