require 'detac'
require 'rubygems'
require 'sqlite3'

# decodes SYNOP in ARGF files, then lists stations in synop-*.tsv format
# using parameters in SQLite3 database "wmo9.sqlite"

class ListStn

  def initialize argv
    db = argv.shift
    raise "specify station db" unless File.readable?(db)
    @db = SQLite3::Database.new(db)
  end

  def close
    @db.close
  end

  def resolve stnid
    a = nil
    sql = <<-ENDSQL
      SELECT lat, lon, hp, stnname, cntname
      FROM vola
      WHERE idxnum = ?
      ORDER BY idxsub ASC
      LIMIT 1
    ENDSQL
    @db.execute(sql, stnid) {|row| a = row }
    a
  end

  def run argv
    for file in argv
      DeTac.new(file).decode {|mimj, dcd|
	stnid = dcd['@ID']
        next unless stnid
	stnid = stnid.to_i
	next if dcd['Lo.4'] or dcd['Lo.6']
	lat, lon, hp, stnname, cntname = resolve(stnid)
	next unless cntname
	name = [stnname, cntname].join(', ').gsub(/\t/, ' ')
	state = []
	state.push 'P' if dcd['P.4']
	state.push 'w' if dcd['ww'] or dcd['iw'] == 2 or dcd['iw'] == 5
	state.push 'N' if dcd['N']
	state.push hp.to_i.to_s
	state = state.join(',')
	printf("%05u\t%s\t%+05.1f%+06.1f/\t%s\t%s\n",
	  stnid, state, lat.to_f, lon.to_f, name, dcd['AHL'])
      }
    end
  ensure
    close
  end

end

ListStn.new(ARGV).run(ARGV)