#!/usr/bin/env ruby -w
# encoding: UTF-8
#
# = Main.rb -- PostRunner - Manage the data from your Garmin sport devices.
#
# Copyright (c) 2014, 2015, 2016 by Chris Schlaeger <cs@taskjuggler.org>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of version 2 of the GNU General Public License as
# published by the Free Software Foundation.
#

require 'optparse'
require 'fit4ruby'
require 'perobs'
require 'fileutils'

require 'postrunner/version'
require 'postrunner/Log'
require 'postrunner/DirUtils'
require 'postrunner/RuntimeConfig'
require 'postrunner/FitFileStore'
require 'postrunner/PersonalRecords'
require 'postrunner/ActivitiesDB'
require 'postrunner/MonitoringDB'
require 'postrunner/EPO_Downloader'

module PostRunner

  class Main

    include DirUtils

    def initialize
      @filter = nil
      @name = nil
      @force = false
      @attribute = nil
      @value = nil
      @db_dir = File.join(ENV['HOME'], '.postrunner')
    end

    def main(args)
      return 0 if (args = parse_options(args)).nil?

      unless $DEBUG
        Kernel.trap('INT') do
          begin
            Log.fatal('Aborting on user request!')
          rescue RuntimeError
            exit 1
          end
        end
      end

      begin
        create_directory(@db_dir, 'PostRunner data')
        ensure_flat_file_db
        @db = PEROBS::Store.new(File.join(@db_dir, 'database'),
                                { :engine => PEROBS::FlatFileDB })
        # Create a hash to store configuration data in the store unless it
        # exists already.
        cfg = (@db['config'] ||= @db.new(PEROBS::Hash))
        cfg['unit_system'] ||= :metric
        cfg['version'] ||= VERSION
        # First day of the week. 0 means Sunday, 1 Monday and so on.
        cfg['week_start_day'] ||= 1
        # We always override the data_dir as the user might have moved the data
        # directory. The only reason we store it in the DB is to have it
        # available throught the application.
        cfg['data_dir'] = @db_dir
        # Always update html_dir setting so that the DB directory can be moved
        # around by the user.
        cfg['html_dir'] = File.join(@db_dir, 'html')

        setup_directories
        retval = execute_command(args)
        @db.exit

        return retval

      rescue Exception => e
        if e.is_a?(SystemExit) || e.is_a?(Interrupt)
          $stderr.puts e.backtrace.join("\n") if $DEBUG
        elsif e.is_a?(Fit4Ruby::Abort)
          # Programm execution error that does not warrant a backtrace to be
          # printed.
          return -1
        else
          Log.error("#{e}\n#{e.backtrace.join("\n")}\n\n" +
                    "#{'*' * 79}\nYou have triggered a bug in PostRunner " +
                    "#{VERSION}!")
        end
        return -1
      end
    end

    private

    def parse_options(args)
      parser = OptionParser.new do |opts|
        opts.banner = "Usage postrunner <command> [options]"

        opts.separator <<"EOT"

Copyright (c) 2014, 2015, 2016 by Chris Schlaeger

This program is free software; you can redistribute it and/or modify it under
the terms of version 2 of the GNU General Public License as published by the
Free Software Foundation.
EOT

        opts.separator ""
        opts.separator "Options for the 'dump' command:"
        opts.on('--filter-msg N', Integer,
                'Only dump messages of type number N') do |n|
          @filter = Fit4Ruby::FitFilter.new unless @filter
          @filter.record_numbers = [] unless @filter.record_numbers
          @filter.record_numbers << n.to_i
        end
        opts.on('--filter-msg-idx N', Integer,
                'Only dump the N-th message of the specified types') do |n|
          @filter = Fit4Ruby::FitFilter.new unless @filter
          @filter.record_indexes = [] unless @filter.record_indexes
          @filter.record_indexes << n.to_i
        end
        opts.on('--filter-field name', String,
                'Only dump the field \'name\' of the selected messages') do |n|
          @filter = Fit4Ruby::FitFilter.new unless @filter
          @filter.field_names = [] unless @filter.field_names
          @filter.field_names << n
        end
        opts.on('--filter-undef',
                "Don't show fields with undefined values") do
          @filter = Fit4Ruby::FitFilter.new unless @filter
          @filter.ignore_undef = true
        end
        opts.on('--force',
                'Import files even if they have been deleted from the ' +
                'database before.') do
          @force = true
        end

        opts.separator ""
        opts.separator "Options for the 'import' command:"
        opts.on('--name name', String,
                'Name the activity to the specified name') do |n|
          @name = n
        end

        opts.separator ""
        opts.separator "General options:"
        opts.on('--dbdir dir', String,
                'Directory for the activity database and related files') do |d|
          @db_dir = d
        end
        opts.on('--debug', 'Enable debug mode') do
          $DEBUG = true
        end
        opts.on('-v', '--verbose',
                'Show internal messages helpful for debugging problems') do
          Log.level = Logger::DEBUG
        end
        opts.on('-h', '--help', 'Show this message') do
          $stdout.puts opts
          return nil
        end
        opts.on('--version', 'Show version number') do
          puts VERSION
          return nil
        end

        opts.separator <<"EOT"

Commands:

check [ <fit file> | <ref> ... ]
           Check the provided FIT file(s) for structural errors. If no file or
           reference is provided, the complete archive is checked.

daily [ <YYYY-MM-DD> ]
           Print the monitoring statistics for the requested day and the
           following night. If no date is given, yesterday's date will be used.

delete <ref>
           Delete the activity from the archive.

dump <fit file> | <ref>
           Dump the content of the FIT file.

events [ <ref> ]
           List all the events of the specified activies.

import [ <fit file> | <directory> ]
           Import the provided FIT file(s) into the postrunner database. If no
           file or directory is provided, the directory that was used for the
           previous import is being used.

list
           List all FIT files stored in the database.

monthly [ <YYYY-MM-DD> ]

           Print a table with various statistics for each day of the specified
           month. If no date is given, yesterday's month will be used.

records
           List all personal records.

rename <new name> <ref>
           For the specified activities replace current activity name with a
           new name that describes the activity. By default the activity name
           matches the FIT file name.

set <attribute> <value> <ref>
           For the specified activies set the attribute to the given value. The
           following attributes are supported:

           name:     The activity name (defaults to FIT file name)
           norecord: Ignore all records from this activity (value must true
                     or false)
           note:     A comment or summary of the activity
           type:     The type of the activity
           subtype:  The subtype of the activity

show [ <ref> | <YYYY-MM-DD> ]
           Show the referenced FIT activity or monitoring data for the given
           date in a web browser. If no argument is provided show the list of
           activities in the database.

sources [ <ref> ]
           Show the data sources for the various measurements and how they
           changed during the course of the activity.

summary <ref>
           Display the summary information for the FIT file.

units <metric | statute>
           Change the unit system.

htmldir <directory>
           Change the output directory for the generated HTML files

update-gps Download the current set of GPS Extended Prediction Orbit (EPO)
           data and store them on the device.

weekly [ <YYYY-MM-DD> ]

           Print a table with various statistics for each day of the specified
           week. If no date is given, yesterday's week will be used.


<fit file> An absolute or relative name of a .FIT file.

<ref>      The index or a range of indexes to activities in the database.
           :1 is the newest imported activity
           :-1 is the oldest imported activity
           :1-2 refers to the first and second activity in the database
           :1--1 refers to all activities
EOT

      end

      begin
        parser.parse!(args)
      rescue OptionParser::InvalidOption
        Log.error "#{$!}\n" + help
        return nil
      end
    end

    def setup_directories
      create_directory(@db['config']['html_dir'], 'HTML output')

      %w( icons jquery flot openlayers postrunner ).each do |dir|
        # This file should be in lib/postrunner. The 'misc' directory should be
        # found in '../../misc'.
        misc_dir = File.realpath(File.join(File.dirname(__FILE__),
                                           '..', '..', 'misc'))
        unless Dir.exists?(misc_dir)
          Log.abort "Cannot find 'misc' directory under '#{misc_dir}': #{$!}"
        end
        src_dir = File.join(misc_dir, dir)
        unless Dir.exists?(src_dir)
          Log.abort "Cannot find '#{src_dir}': #{$!}"
        end
        dst_dir = @db['config']['html_dir']

        begin
          FileUtils.cp_r(src_dir, dst_dir)
        rescue IOError
          Log.abort "Cannot copy auxilliary data directory '#{dst_dir}': #{$!}"
        end
      end
    end

    def execute_command(args)
      # Create or load the FitFileStore data.
      unless (@ffs = @db['file_store'])
        @ffs = @db['file_store'] = @db.new(FitFileStore)
      end
      # Create or load the PersonalRecords data.
      unless (@records = @db['records'])
        @records = @db['records'] = @db.new(PersonalRecords)
      end
      handle_version_update
      import_legacy_archive

      case (cmd = args.shift)
      when 'check'
        if args.empty?
          @db.check(true)
          @ffs.check
          Log.info "Database cleanup started. Please wait ..."
          @db.gc
          Log.info "Database cleanup finished"
        else
          process_files_or_activities(args, :check)
        end
      when 'daily'
        # Get the date of requested day in 'YY-MM-DD' format. If no argument
        # is given, use the current date.
        @ffs.daily_report(day_in_localtime(args, '%Y-%m-%d'))
      when 'weekly'
        # Get the date of requested day in 'YY-MM-DD' format. If no argument
        # is given, use the current date.
        @ffs.weekly_report(day_in_localtime(args, '%Y-%m-%d'))
      when 'monthly'
        # Get the date of requested day in 'YY-MM-DD' format. If no argument
        # is given, use the current date.
        @ffs.monthly_report(day_in_localtime(args, '%Y-%m-01'))
      when 'delete'
        process_activities(args, :delete)
      when 'dump'
        @filter = Fit4Ruby::FitFilter.new unless @filter
        process_files_or_activities(args, :dump)
      when 'events'
        process_files_or_activities(args, :events)
      when 'import'
        if args.empty?
          # If we have no file or directory for the import command, we get the
          # most recently used directory from the runtime config.
          process_files([ @db['config']['import_dir']  ], :import)
        else
          process_files(args, :import)
          if args.length == 1 && Dir.exists?(args[0])
            # If only one directory was specified as argument we store the
            # directory for future use.
            @db['config']['import_dir'] = args[0]
          end
        end
      when 'list'
        @ffs.list_activities
      when 'records'
        puts @records.to_s
      when 'rename'
        unless (@name = args.shift)
          Log.abort 'You must provide a new name for the activity'
        end
        process_activities(args, :rename)
      when 'set'
        unless (@attribute = args.shift)
          Log.abort 'You must specify the attribute you want to change'
        end
        unless (@value = args.shift)
          Log.abort 'You must specify the new value for the attribute'
        end
        process_activities(args, :set)
      when 'show'
        if args.empty?
          @ffs.show_list_in_browser
        elsif args[0] =~ /\A2\d{3}-\d{2}-\d{2}\z/
          # Likely a valid YYYY-MM-DD date. Show the monitoring data for the
          # given day in a browser.
          @ffs.show_monitoring(args[0])
        else
          process_activities(args, :show)
        end
      when 'sources'
        process_activities(args, :sources)
      when 'summary'
        process_activities(args, :summary)
      when 'units'
        change_unit_system(args)
      when 'htmldir'
        change_html_dir(args)
      when 'update-gps'
        update_gps_data
      when nil
        Log.abort("No command provided. " + help)
      else
        Log.abort("Unknown command '#{cmd}'. " + help)
      end

      # Ensure that all updates are written to the database.
      @db.sync

      0
    end

    def help
      "See 'postrunner -h' for more information."
    end

    def process_files_or_activities(files_or_activities, command)
      files_or_activities.each do |foa|
        if foa[0] == ':'
          process_activities([ foa ], command)
        else
          process_files([ foa ], command)
        end
      end
    end

    def process_activities(activity_refs, command)
      if activity_refs.empty?
        Log.abort("You must provide at least one activity reference.")
      end

      activity_refs.each do |a_ref|
        if a_ref[0] == ':'
          activities = @ffs.find(a_ref[1..-1])
          if activities.empty?
            Log.warn "No matching activities found for '#{a_ref}'"
            return
          end
          activities.each { |a| process_activity(a, command) }
        else
          Log.abort "Activity references must start with ':': #{a_ref}"
        end
      end

      nil
    end

    def process_files(files_or_dirs, command)
      if files_or_dirs.empty?
        Log.abort("You must provide at least one .FIT file name.")
      end

      files_or_dirs.each do |fod|
        if File.directory?(fod)
          Dir.glob(File.join(fod, '*.FIT')).each do |file|
            process_file(file, command)
          end
        else
          process_file(fod, command)
        end
      end
    end

    # Process a single FIT file according to the given command.
    # @param file [String] File name of a FIT file
    # @param command [Symbol] Processing instruction
    # @return [TrueClass, FalseClass] true if command was successful, false
    #         otherwise
    def process_file(file, command)
      case command
      when :check, :dump
        read_fit_file(file)
      when :import
        import_fit_file(file)
      else
        Log.fatal("Unknown file command #{command}")
      end
    end

    # Import the given FIT file.
    # @param fit_file_name [String] File name of the FIT file
    # @return [TrueClass, FalseClass] true if file was successfully imported,
    #         false otherwise
    def import_fit_file(fit_file_name)
      begin
        fit_entity = Fit4Ruby.read(fit_file_name)
      rescue Fit4Ruby::Error
        Log.error $!
        return false
      end

      if fit_entity.is_a?(Fit4Ruby::Activity) ||
         fit_entity.is_a?(Fit4Ruby::Monitoring_B)
        return @ffs.add_fit_file(fit_file_name, fit_entity, @force)
      else
        Log.error "#{fit_file_name} is not a recognized FIT file"
        return false
      end
    end

    def process_activity(activity, command)
      case command
      when :check
        activity.check
      when :delete
        @ffs.delete_activity(activity)
      when :dump
        activity.dump(@filter)
      when :events
        activity.events
      when :rename
        @ffs.rename_activity(activity, @name)
      when :set
        if @attribute == 'name'
          # We have to handle the 'name' attribute as special case as we have
          # to update some HTML reports as well.
          @ffs.rename_activity(activity, @value)
        else
          @ffs.set_activity_attribute(activity, @attribute, @value)
        end
      when :show
        activity.show
      when :sources
        activity.sources
      when :summary
        activity.summary
      else
        Log.fatal("Unknown activity command #{command}")
      end
    end

    def read_fit_file(fit_file)
      return Fit4Ruby::read(fit_file, @filter)
    end

    def change_unit_system(args)
      if args.length != 1 || !%w( metric statute ).include?(args[0])
        Log.error("You must specify 'metric' or 'statute' as unit system.")
      end

      if @db['config']['unit_system'].to_s != args[0]
        @db['config']['unit_system'] = args[0].to_sym
        @ffs.change_unit_system
      end
    end

    def change_html_dir(args)
      if args.length != 1
        Log.error('You must specify a directory')
      end

      if @db['config']['html_dir'] != args[0]
        @db['config']['html_dir'] =  args[0]
        @ffs.create_directories
        @ffs.generate_all_html_reports
      end
    end

    def update_gps_data
      epo_dir = File.join(@db_dir, 'epo')
      create_directory(epo_dir, 'GPS Data Cache')
      epo_file = File.join(epo_dir, 'EPO.BIN')

      if !File.exists?(epo_file) ||
         (File.mtime(epo_file) < Time.now - (6 * 60 * 60))
        # The EPO file only changes every 6 hours. No need to download it more
        # frequently if it already exists.
        if EPO_Downloader.new.download(epo_file)
          unless (remotesw_dir = @db['config']['import_dir'])
            Log.error "No device directory set. Please import an activity " +
                      "from your device first."
            return
          end
          remotesw_dir = File.join(remotesw_dir, '..', 'REMOTESW')
          unless Dir.exists?(remotesw_dir)
            Log.error "Cannot find '#{remotesw_dir}'. Please connect and " +
                      "mount your Garmin device."
            return
          end
          begin
            FileUtils.cp(epo_file, remotesw_dir)
          rescue
            Log.error "Cannot copy EPO.BIN file to your device at " +
                      "'#{remotesw_dir}'."
            return
          end
        end
      end
    end

    def day_in_localtime(args, format)
      begin
        (args.empty? ? Time.now - 24 * 60 * 60 : Time.parse(args[0])).
          localtime.strftime(format)
      rescue ArgumentError
        Log.abort("#{args[0]} is not a valid date. Use YYYY-MM-DD format.")
      end
    end

    def handle_version_update
      if @db['config']['version'] != VERSION
        Log.warn "PostRunner version upgrade detected."
        @ffs.handle_version_update
        @db['config']['version'] = VERSION
        Log.info "Version upgrade completed."
      end
    end

    # Earlier versions of PostRunner used a YAML file to store the activity
    # data. This method transfers the data from the old storage to the new
    # FitFileStore based database.
    def import_legacy_archive
      old_fit_dir = File.join(@db_dir, 'old_fit_dir')
      create_directory(old_fit_dir, 'Old Fit')

      cfg = RuntimeConfig.new(@db_dir)
      activities = ActivitiesDB.new(@db_dir, cfg).activities
      # Ensure that activities are sorted from earliest to last to properly
      # recognize the personal records during import.
      activities.sort! { |a1, a2| a1.timestamp <=> a2.timestamp }
      activities.each do |activity|
        file_name = File.join(@db_dir, 'fit', activity.fit_file)
        next unless File.exists?(file_name)

        Log.info "Converting #{activity.fit_file} to new DB format"
        @db.transaction do
          unless (new_activity = @ffs.add_fit_file(file_name))
            Log.warn "Cannot convert #{file_name} to new database format"
            next
          end
          new_activity.sport = activity.sport
          new_activity.sub_sport = activity.sub_sport
          new_activity.name = activity.name
          new_activity.norecord = activity.norecord
          FileUtils.move(file_name, File.join(old_fit_dir, activity.fit_file))
        end
      end
    end

    def ensure_flat_file_db
      # Earlier versions of the PEROBS library used the BTreeDB as standard
      # database format. With the introduction of FlatFileDB a much more
      # compact and faster alternative is available now. Check existing
      # installations and convert the database if needed.
      database_dir = File.join(@db_dir, 'database')
      return unless Dir.exist?(File.join(database_dir, '000'))

      Log.info "Converting BTreeDB based database to FlatFileDB format"
      db = PEROBS::Store.new(database_dir)
      if Dir.exist?(database_dir + '-new')
        # This may be a leftover from a failed conversion.
        FileUtils.rm_rf(database_dir + '-new')
      end
      db.copy(database_dir + '-new', { :engine => PEROBS::FlatFileDB })
      db.exit

      FileUtils.mv(database_dir, database_dir + '-old')
      FileUtils.mv(database_dir + '-new', database_dir)

      db = PEROBS::Store.new(database_dir, { :engine => PEROBS::FlatFileDB })
      db.check
      db.exit
      # TODO: Delete -old directory in some later version when we have some
      # confidence that the conversion always works.
      Log.info "DB conversion completed successfully"
    end
  end

end