class EventNlp

# File lib/event_nlp.rb, line 29
def initialize(now=Time.now, params: {}, debug: false)
  
  super()
  
  @now = now
  @params = params
  expressions(@params)
  @debug = debug

end

# File lib/event_nlp.rb, line 40
def parse(s)

  @params[:input] = s
  r = run_route(s)

  return unless r.is_a? Hash
  
  OpenStruct.new({input: s}.merge r)
  
end

# File lib/event_nlp.rb, line 53
def expressions(params)     

  starting = /(?:\(?\s*starting (\d+\w{2} \w+\s*\w*)(?: until (.*))?\s*\))?/
  weekdays2 = (Date::DAYNAMES + Date::ABBR_DAYNAMES).join('|').downcase    
  weekdays = "(%s)" % weekdays2
  months = "(%s)" % (Date::MONTHNAMES[1..-1] + Date::ABBR_MONTHNAMES[1..-1])\
                                                      .join('|').downcase
  times = /(?: *(?:at |@ |from )?(\d+(?::\d+)?(?:[ap]m|\b)) *)/
  times2 = /\d+(?::\d+)?[ap]m-\d+(?::\d+)?[ap]m|\d+(?::\d+)?-\d+(?::\d+)?/
  times3 = /(\d+(?::\d+)?[ap]m-\d+(?::\d+)?[ap]m|\d+(?::\d+)?-\d+(?::\d+)?)/    
  days = /(\d+(?:st|nd|rd|th))/
  periods = /day|week|month/
  
  #weekdays = Date::DAYNAMES.join('|').downcase
  #
  
  #times = /(?: *at )?\d[ap]m/

 # e.g. electricity bill on the 28th of every month

 get /(.*) on the (#{days}) of every (#{periods})/ do |title, day, recurring|


    raw_d = Chronic.parse(day)
    
    # if the date is less than now then increment it by a month
    d = raw_d < @now ? (raw_d.to_date >> 1).to_time : raw_d
    
    
    if @debug then
      puts [0.1, title, recurring, d].inspect.debug
    end
    
    {title: title, recurring: recurring, date: d}      
    
  end
  

  get /^(.*)\s+(every \d\w+ \w+#{times})\s*#{starting}/ do \
                                 |title, recurring, time, raw_date, end_date|

    input = params[:input].clone            
    d = Chronic.parse(raw_date + ' ' + time.to_s)
    
    if recurring =~ /day|week/ then

      if d < @now then

        new_date = CronFormat.new(ChronicCron.new(recurring)\
                                  .to_expression, d).to_time
        input.gsub!(raw_date, new_date\
                    .strftime("#{new_date.day.ordinal} %b %Y"))             
        d = new_date
        
      end
    end
    
    if @debug then
      puts ["0.2".highlight, input, title, recurring, time, raw_date, end_date].inspect.debug
    end
    
    {input: input, title: title, recurring: recurring, date: d, 
     end_date: end_date}      
    
  end
  
  # e.g. some event 1st Monday of every month (starting 3rd Jul 2017)

  get /^(.*)\s+(\d(?:st|nd|rd|th) \w+ of every \w+(?: at (\d+[ap]m) )?)\s*#{starting}/ do \
                                 |title, recurring, time, raw_date, end_date|

    input = params[:input].clone
    d = Chronic.parse(raw_date)
    
    if recurring =~ /day|week|month/ then        
      
      if d < @now then

        new_date = CronFormat.new(ChronicCron.new(recurring)\
                                  .to_expression, d).to_time
        input.gsub!(raw_date, new_date\
                    .strftime("#{new_date.day.ordinal} %b %Y"))        
        d = new_date
      else
        d = ChronicCron.new(recurring, d.to_date.to_time).to_time
      end
    end
    
    puts ['0.3'.highlight, title, recurring, time, raw_date, end_date].inspect.debug if @debug
    {input: input, title: title, recurring: recurring, date: d, end_date: 
                                                                    end_date}
    
  end    

  # some event every 2 weeks
  # some event every 2 weeks at 6am starting from 14th Jan
  # some event every 2 weeks at 6am starting from 18th Feb until 28th Oct
  # some event every 2nd Monday (starting 7th Nov 2016)
  # some event every 2nd Monday (starting 7th Nov until 3rd Dec)
  # some event every 2 weeks (starting 02/11/17)
  # some event every Wednesday 1pm-4pm
  #
  get /^(.*)(every .*)/ do |title, recurring|

    input = params[:input].clone
    raw_start_date = recurring[/(?<=starting )[^\)]+/]
    
    d = if raw_start_date then
      start_date = Chronic.parse(raw_start_date, now: @now - 1, 
                                 :endian_precedence => :little)

      puts ('recurring: ' + recurring.inspect).debug if @debug
      puts ('start_date: ' + start_date.inspect).debug if @debug
      
      if @now > start_date then
        exp = ChronicCron.new(recurring, start_date, debug: @debug).to_expression
        puts 'exp: ' + exp.inspect if @debug
        
        cf = CronFormat.new(exp, start_date, debug: @debug)
        puts ('cf.to_time: '  + cf.to_time.inspect).debug if @debug
        cf.next until cf.to_time > start_date
        
        new_date = cf.to_time
        input.gsub!(/(?<=starting )[^\)]+/, new_date\
                    .strftime("#{new_date.day.ordinal} %b %Y"))
        new_date

      else
        start_date
      end
      
    else
      exp = ChronicCron.new(recurring).to_expression
      cf = CronFormat.new(exp, @now)
      cf.to_time
    end
    

    
    if recurring =~ /-/ then
      end_date = Chronic.parse d.to_date.to_s + ' ' + 
          recurring[/(?<=-)\d+(?::\d+)?(?:[ap]m)?/] 
    end
        
    puts ['0.5'.highlight, title, recurring, d].join("\n").debug if @debug
    {input: input, title: title.rstrip, recurring: recurring, 
     date: d, end_date: end_date }
    
  end    
  
  # some meeting 3rd thursday of the month at 7:30pm
  # some meeting First thursday of the month at 7:30pm
  get /(.*)\s+(\w+ \w+day of (?:the|every) month at .*)/ do 
                                                           |title, recurring|

    puts ['1'.highlight, title, recurring].inspect.debug if @debug
    { title: title, recurring: recurring }

  end
  
  
  # 7th Oct Euston Station (meet at Timothy's house at 7pm)
  get /^(\d(?:st|nd|rd|th) \w+) *(.*)\s+at\s+(\w+)/i do \
      |raw_day, title, time|
    
    d = Chronic.parse(raw_day + ' ' + time)
    
    puts ['1.5'.highlight, title, raw_day, time].inspect.debug if @debug
    { title: title, date: d }
    
  end    

  # some event Wednesday
  # some event Wednesday 11am
  
  relative_day = '|today|tomorrow|tonight'
  get /^(.*)\s+(#{weekdays2+relative_day}\b)(?: \(([^\)]+)\)) (at \d{1,2}(?::\d{2})?(?:[ap]m)?)/i \
                                                         do |title, raw_date, date2, time2|
    puts ('time2: ' + time2.inspect).debug if @debug
    puts ('date2: ' + date2).debug if @debug
    puts ('raw_date: ' + raw_date).debug if @debug
    
    d = if date2 then
      Chronic.parse(date2 + ' '+ time2.to_s)
    else
      Chronic.parse(raw_date + ' '+ time2)
    end
    
    puts ['4'.highlight, title, raw_date, date2, time2].inspect.debug if @debug
    {title: title, date: d }
     
  end
      
  # Group meeting Red Hall 2pm-4pm on Monday (4th Dec 2017)
  get /^(.*)\s+(#{times2})(?: on) +#{weekdays}\b(?: \(([^\)]+)\))?/i \
      do |title, xtimes, raw_day, actual_date|
    
    if @debug then
      puts ('actual_date: ' + actual_date.inspect).debug
      puts ('raw_day: ' + raw_day.inspect).debug
      puts ('xtimes: ' + xtimes.inspect).debug
    end
    
    input = params[:input].clone
    
    if actual_date then
      d = Chronic.parse actual_date
    else
      d = Chronic.parse(raw_day)        
      input.sub!(/#{weekdays}\b/i,
                 %Q(#{raw_day} (#{d.strftime("#{d.day.ordinal} %b %Y")})))        
    end

    t1, t2 = xtimes.split(/-/,2)
    
    puts ('d: ' + d.inspect).debug if @debug

    d1, d2 = [t1, t2].map {|t| Chronic.parse([d.to_date.to_s, t].join(' ')) }
          
    puts ['4.65'.highlight, input, title, raw_day, d1, d2].inspect.debug if @debug
    
    {input: input, title: title, date: d1, end_date: d2 }
    
  end          
  
  # hall 2 friday at 11am

  get /^(.*)\s+#{weekdays}\b(?: \(([^\)]+)\))?(#{times})?/i \
      do |title, raw_day, actual_date, time|
    
    if @debug then
      puts ('actual_date: ' + actual_date.inspect).debug
      puts ('raw_day: ' + raw_day.inspect).debug
      puts ('time: ' + time.inspect).debug
    end
    
    input = params[:input].clone
    
    if actual_date then
      d = Chronic.parse(raw_day + ' ' + time.to_s)
    else
      d = Chronic.parse(raw_day + ' ' + time.to_s)        
      input.sub!(/#{weekdays}/i,
                 %Q(#{raw_day} (#{d.strftime("#{d.day.ordinal} %b %Y")})))        
    end
      
    puts ('d: ' + d.inspect).debug if @debug
    
    puts [1.7, input, title, raw_day].inspect.debug if @debug
    
    {input: input, title: title, date: d }
    
  end        
  
  
  # e.g. 21/05/2017 Forum meetup at Roundpeg from 2pm
  get /^(\d+\/\d+\/\d+)\s+(.*)(?: from|at)\s+(\d+[ap]m)/ do 
                                                  |raw_date, title, raw_time|
    
    d = Chronic.parse(raw_date + ' ' + 
                      raw_time, :endian_precedence => :little)
    recurring = nil            
    
    puts [3, title, raw_date].inspect.debug if @debug
    { title: title, date: d }
  end        
  
  # friday hall 2 11am until 12am
  get /^#{weekdays}\s+(.*)\s+#{times} until #{times}$/i do \
      |raw_day, title, start_time, end_time|
    
    venue = title[/^at +(.*)/,1]
    d = Chronic.parse(raw_day + ' ' + start_time)
    d2 = Chronic.parse(raw_day + ' ' + end_time)
    
    puts ['1.44.3', title, raw_day].inspect.debug if @debug
    { title: title, date: d, end_date: d2, venue: venue }
    
  end       
  
  # friday hall 2 11am
  get /^#{weekdays}\b\s+(.*)\s+(\d+(?::\d{2})?[ap]m)$/i do \
      |raw_day, title, time|
    
    puts [raw_day, title, time].inspect if @debug
    venue = title[/^at +(.*)/,1]
    d = Chronic.parse(raw_day + ' ' + time)
    
    puts [1.44, title, raw_day].inspect.debug if @debug
    { title: title, date: d, venue: venue }
    
  end    

  # Tuesday 10th July hall 2 at 11am
  get /#{weekdays}\b\s+#{days}\s+#{months}\s+(?:at )?(.*)\s+at\s+(#{times})/i \
      do |wday, day, month, title,  time|
    
    d = Chronic.parse([day, month, time].join(' '))
    
    puts ['1.44.5', day, month, title].inspect.debug if @debug
    { title: title, date: d }
    
  end       
  
 
 
  
  # 27-Mar@1436 some important day
  # 25/07/2017 11pm some important day
  #
  get /^(\d+\/\d+\/\d+)\s*(\d+(?:\:\d+)?[ap]m)?\s+([^\*]+)(\*)?/ \
      do |raw_date, time, title, annualar|

    d = Chronic.parse(raw_date + ' ' + time.to_s, 
                      :endian_precedence => :little)
    recurring = nil
    
    if annualar then
      
      recurring = 'yearly'
      if d < @now then
        d = Chronic.parse(raw_date, now: Time.local(@now.year + 1, 1, 1)) 
      end
    end
    
    
    puts [3, title, raw_date, time].inspect.debug if @debug
    { title: title, date: d, recurring: recurring }
  end


  
  # Some event (10 Woodhouse Lane) 30th Nov from 9:15-17:00

  get /^(.*) #{days} #{months}(?: from)? (#{times2})/i do \
      |title, day, month, xtimes|

    t1, t2 = xtimes.split(/-/,2)

    d1 = Chronic.parse([month, day, t1].join(' '))
    d2 = Chronic.parse([month, day, t2].join(' '))

    puts [4.5, title, d1, d2].inspect.debug if @debug

    { title: title, date: d1, end_date: d2 }
  end
  
  # Some event (10 Woodhouse Lane) 30th Nov from 9:15-17:00

  get /^#{weekdays}\b #{months} #{days} #{times3} (.*)/i do \
      |wday, month, day, xtimes, title|

    puts [month, day, xtimes, title].inspect if @debug
    t1, t2 = xtimes.split(/-/,2)

    d1 = Chronic.parse([month, day, t1 + ':00'].join(' '))
    d2 = Chronic.parse([month, day, t2 + ':00'].join(' '))

    puts [4.55, title, d1, d2].inspect.debug if @debug

    { title: title, date: d1, end_date: d2 }
  end    

  # e.g. Wednesday 30th Nov at 9:15 10 Woodhouse Lane

  get /^(?:#{weekdays2}\b) #{days} #{months}(?: at)? #{times}(.*)/i do \
      |day, month, t1, title|

    d1 = Chronic.parse([month, day, t1].join(' '))

    puts [4.6, title, d1].inspect.debug if @debug

    { title: title, date: d1 }
  end    
  
  # Some event (10 Woodhouse Lane) 30th Nov at 9:15-

  get /^(.*) #{days} #{months}(?: at)? (#{times})/i do \
      |title, day, month, t1|


    d1 = Chronic.parse([month, day, t1].join(' '))

    puts [4.7, title, d1].inspect.debug if @debug

    { title: title, date: d1 }
  end

  # hall 2 at 11am
  #
  get /(.*)\s+at\s+(#{times})/i do |title,  time|
    
    d = Chronic.parse(time)
    
    puts [1.45, title].inspect.debug if @debug
    { title: title, date: d }
    
  end         
  
  
  # Council Tax on the last day of the month
  #
  get /^(.*) (?:o[nf] the)\s*last day of the month/i do |title|
    
    td = @now.to_date
    d = Date.civil(td.year, td.month, -1).to_time
    
    puts [5, title].inspect.debug if @debug
    { title: title, date: d }
    
  end        
  
  # Council Tax last day of the month
  #
  get /^(.*) +last day of the month/i do |title|
    
    td = @now.to_date
    d = Date.civil(td.year, td.month, -1).to_time
    
    puts [5.1, title].inspect.debug if @debug
    { title: title, date: d }
    
  end        
  
  # some important day 11 Oct *
  #
  get /^(.*) +(\d+) +#{months} *(\*)?/i \
      do |title, day, month, annualar|
    
    raw_date = day + ' ' + month

    d = Chronic.parse(raw_date, 
                      :endian_precedence => :little)
    recurring = nil
    
    if annualar then
      
      recurring = 'yearly'
      if d < @now then
        d = Chronic.parse(raw_date, 
                          now: Time.local(@now.year + 1, 1, 1)) 
      end
    end
    
    
    puts [6, title, raw_date].inspect.debug if @debug
    { title: title, date: d, recurring: recurring }
  end
  
  
  
  # Tuesday 3rd October gas service at Barbara's house morning 9am-1pm
  #
  get '*' do
    
    s = params[:input]
    
    time1, time2, month, weekday, day, end_date, annualar  = nil, nil, nil, 
        nil, nil, nil, false

    s2 = s.sub(/#{times}/i) {|x| time1 = x; ''}
    puts 's2: ' + s2.inspect if @debug
    s3 = s2.sub(/-(?=\d)/,'').sub(/#{times}/i) {|x| time2 = x; ''}
    s4 = s3.sub(/ *#{weekdays} */i) {|x| weekday = x; ''}
    s5 = s4.sub(/ *#{months} */i) {|x| month = x; ''}
    s6 = s5.sub(/ *#{days} */i) {|x| day = x; ''}
    s7 = s6.sub(/\*$/) {|x| annualar = true; ''}
    title = s7.strip

    raw_date = [day, month].compact.join(' ')
    raw_date = weekday if raw_date.empty?

    d = Chronic.parse(raw_date + ' ' + time1.to_s, 
                      :endian_precedence => :little, now: @now)
    
    if time2 then
      end_date = Chronic.parse(raw_date + ' ' + time2.to_s, 
                      :endian_precedence => :little)
    end
    
    recurring = nil
    
    if annualar then
      
      recurring = 'yearly'
      if d < @now then
        d = Chronic.parse(raw_date, now: Time.local(@now.year + 1, 1, 1)) 
      end
    end      
    
    puts [10, title, raw_date, time1].inspect.debug if @debug
    { title: title, date: d, end_date: end_date, recurring: recurring }
  end    
  
  
end