#!/usr/bin/env ruby

# Purpose: use the command line to edit a CSV file

if ARGV[0] == '-h'
  puts "Usage: csv-edit <CSV FILE>"
  exit(0)
end

require 'csv-utils'
require 'tty-prompt'
require 'io/console'

csv_file = ARGV[0]
raise("#{csv_file} not found") unless File.exist?(csv_file)

def screen_width
  @screen_width ||= (IO.console.winsize[1] - 10)
end

def escape_csv_value(value)
  value
    .gsub("\r", "\\r")
    .gsub("\n", "\\n")
    .gsub("\t", "\\t")
end

def csv_row_to_s(row_number, row)
  str = "#{row_number}. "
  sep = ''
  row.each_with_index do |(k, v), idx|
    if idx == 0 || v.to_s != ''
      str += "#{sep}#{k}: #{escape_csv_value(v)}"
      sep = ', '
    end

    break if str.size >= screen_width
  end

  if str.size > screen_width
    return str[0..screen_width] + ' ...'
  end

  str
end

def add_row(csv_iterator)
  csv_iterator.headers.each_with_object({}) { |header, obj| obj[header] = '' }
end

def pick_csv_row(prompt, rows, starting_row_idx, max_rows_to_display=100_000)
  choices = [{name: '<< Add Row >>', value: nil}]
  rows.each_with_index do |row, idx|
    next unless idx >= starting_row_idx

    row_number = idx + 1
    choices << {name: csv_row_to_s(row_number, row), value: row}

    break if choices.size > max_rows_to_display
  end

  prompt.select(('Pick row to edit'), choices)
end

def edit_row(prompt, row)
  done = false
  while !done
    choices = [{name: '<< Done >>', value: true}]

    row.each do |column_name, column_value|
      name = "#{column_name}: #{column_value}"
      choices << {name: name, value: column_name}
    end

    choice = prompt.select('Edit?', choices)
    if choice == true
      done = true
      break
    end

    new_value = prompt.ask("#{choice}: ", value: row[choice].to_s)
    row[choice] = new_value
  end

  row
end

csv_iterator = CSVUtils::CSVIterator.new(csv_file)
rows = csv_iterator.to_a

prompt = TTY::Prompt.new

prompt.on(:keypress) do |event|
  if event.value == "\u0013" # CTRL-s
    new_csv_file = csv_file + '.' + Time.now.strftime('%Y%m%dT%H%M%S') + '.csv'
    puts "\nsaving to #{new_csv_file}"
    CSV.open(new_csv_file, 'wb') do |out|
      out << csv_iterator.headers
      rows.each do |row|
        out << row.values
      end
    end
    exit(0)
  elsif event.value == "\u0011" # CTRL-q
    puts "\nquiting"
    exit(0)
  end
end

while true
  row = pick_csv_row(prompt, rows, 0, 100)

  if row.nil?
    row = add_row(csv_iterator)
    rows << row
  end

  edit_row(prompt, row)
end