#!/usr/bin/env groovy

import java.io.BufferedWriter
import java.io.FileInputStream
import java.io.FileWriter
import java.io.OutputStreamWriter
import java.util.Calendar
import java.util.Date
import java.text.SimpleDateFormat

//import jdbernard.timestamper.Timeline

SimpleDateFormat paramDateFormat = new SimpleDateFormat("yyyy-MM-dd")

def cl = new CliBuilder(usage: 'pretty_format.groovy [-i input_file] [-o output_file] [OPTIONS]')
cl.h(argName: 'help', 'Show usage information.')
cl.i(argName: 'input_file', longOpt: 'input-file', args: 1, 'Input timeline file (if not present, read from STDIN)')
cl.o(argName: 'output_file', longOpt: 'output-file', args: 1, 'File to write formatted output to (if not present, output is written to STOUT).')
cl.s(argName: 'start_date', longOpt: 'start-date', args: 1, 'Exclude all entries before this date (YYYY-MM-DD).')
cl.e(argName: 'end_date', longOpt: 'end-date', args: 1, 'Exclude all entries after this date (YYYY-MM-DD).')
cl.p(argName: 'entry_period', longOpt: 'period', args: 1, 'Shorthand notation for the period of entries to include in the output file. The format '
    + 'takes the following format: MUN where M = number of units between current time and start time, N = number of units between start time and '
    + 'end time, and U = time unit. Valid values for U are: D - day, W - week, M - month, and Y - year. For example: 0W1 means this week '
    + 'and the next. 2D5 means a five day period, starting two days from today. -1Y1 means last year, this year, and the next year.')

def opt = cl.parse(args)

if (!opt) System.exit(1);

is = System.in;
os = new BufferedWriter(new OutputStreamWriter(System.out));
start = false;
end = false;

if (opt.i) is = new FileInputStream(opt.i);
if (opt.o) os = new BufferedWriter(new FileWriter(opt.o));

if (opt.s) start = paramDateFormat.parse(opt.s);
if (opt.e) end = paramDateFormat.parse(opt.e);

if (opt.p) {
  int offset
  def unit
  def lower_unit
  int length

  (opt.p =~ /([\-n]?)(\d+)([dwmyDWMY])(\d+)/).each { all, nx, x, y, z ->
    offset = x.toInteger(); unit = y; length = z.toInteger() - 1;
    if (nx) offset = -offset;
  }

  start = Calendar.getInstance()
  start.set(Calendar.HOUR_OF_DAY, start.getMinimum(Calendar.HOUR_OF_DAY));
  start.set(Calendar.MINUTE, start.getMinimum(Calendar.MINUTE));
  start.set(Calendar.SECOND, start.getMinimum(Calendar.SECOND));

  end = Calendar.getInstance()
  end.set(Calendar.HOUR_OF_DAY, end.getMaximum(Calendar.HOUR_OF_DAY));
  end.set(Calendar.MINUTE, end.getMaximum(Calendar.MINUTE));
  end.set(Calendar.SECOND, end.getMaximum(Calendar.SECOND));

  switch (unit) {
    case 'd': case 'D': default:
      unit = Calendar.DAY_OF_YEAR
      lower_unit = Calendar.HOUR_OF_DAY
      break
    case 'w': case 'W':
      unit = Calendar.WEEK_OF_YEAR
      lower_unit = Calendar.DAY_OF_WEEK
      break
    case 'm': case 'M':
      unit = Calendar.MONTH
      lower_unit = Calendar.DAY_OF_MONTH
      break
    case 'y': case 'Y':
      unit = Calendar.YEAR
      lower_unit = Calendar.DAY_OF_YEAR
      break
  }

  start.add(unit, offset)
  start.set(lower_unit, start.getActualMinimum(lower_unit))

  end.setTime(start.getTime())
  end.add(unit, length)
  end.set(lower_unit, end.getActualMaximum(lower_unit))

  start = start.getTime()
  end = end.getTime()
}

//Timeline timeline = Timeline.readFromStream(is);

print "Start: ${paramDateFormat.format(start)}\n"
print "End: ${paramDateFormat.format(end)}\n"