#
# concurrent events snapon
#
# This snapon calculates the number of concurrent events, using start time and duration values
#

concurrent_events = {

  version = "1.2"

  # ????-??-?? - GMF - 1.0 - Initial creation
  # 2012-05-08 - GMF - 1.1 - Added track_per_resource option
  # 2012-05-14 - GMF - 1.2 - Fixed prompting of track-per-resource options in UI
 
  label = "$lang_admin.snapons.concurrent_events.label"
  comment = "$lang_admin.snapons.concurrent_events.comment"
  config_snapon_category = ""

  parameters = {
  
    date_time_field = {
    
      parameter_value = "date_time"
      
      validation_type = "string"
      
      form_element_label = "$lang_admin.snapons.concurrent_events.parameters.date_time_field.form_element_label"
      form_element_type = "select"
      select_options_source = "database_fields"
      
      description = ""
    
    } # date_time_field
 
    duration_field = {
      
      parameter_value = "x_duration"
      
      validation_type = "string"
      
      form_element_label = "$lang_admin.snapons.concurrent_events.parameters.duration_field.form_element_label"
      form_element_type = "select"
      select_options_source = "database_fields"
      
      description = ""
      
    } # duration_field

    track_per_resource = {

      parameter_value = "false"
      
      form_element_label = "$lang_admin.snapons.concurrent_events.parameters.track_per_resource.form_element_label"
      form_element_type = "checkbox"
      
      description = ""
      
    } # track_per_resource

    resource_field = {
    
      parameter_value = "page"
      
      validation_type = "string"
      
      form_element_label = "$lang_admin.snapons.concurrent_events.parameters.resource_field.form_element_label"
      form_element_type = "select"
      select_options_source = "database_fields"
      
      description = ""
    
    } # resource_field
 
    concurrent_events_name = {
    
      parameter_value = "Concurrent events" # LM
      final_node_name = "session_entrances"
      
      validation_type = "field_label"
      validate_field_label_for = {
        database_fields = true
        report_fields = true
      }
      
      form_element_label = "{=capitalize(expand(lang_stats.field_labels.concurrent_events))=}"
      form_element_type = "text"
      form_element_width = "380"
      
      description = ""
    
    } #  concurrent_events_name
    
      
  } # parameters
  
  parameters_form = {

    group_1 = {
      description = "$lang_admin.snapons.concurrent_events.parameters_form.group_1.description"
      parameters = {
        date_time_field = true
        duration_field = true
        concurrent_events_name = true
	track_per_resource = true
        resource_field = true
      } # parameters
    } # group 1
    
  } # parameters_form
  
  
  attach_operations = {

    # When attaching: Add the concurrent events database fields
    add_database_field = {
      type = "add_database_fields"
      fields = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {

          label = "{= @parameters{'concurrent_events_name'}{'parameter_value'} =}"
          type = "int"
          derivation_method = "database_filter"
          aggregation_method = "max"
          category = ""
          index = "true"
          suppress_top = "0"
          suppress_bottom = "2"
          integer_bits = "0"

        } # concurrent_events_name
  
      } # fields

    } # add_database_field

    # When attaching: add the database filter to calculate the field
    add_database_filter = {

      type = "add_database_filters"

      filters = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
  
          conditions = {
  
            # Sort chronologically
            sort = {
              type = "sort"
              fields = {
                date_time = {
                  column_name = "{= @parameters{'date_time_field'}{'parameter_value'} =}"
                }
              } # fields
            } # sort
  
            # The current_events variable keeps track of how many events there are right now, for the current resource
            current_events = {
              type = "variable"
              variable_name = "current_events"
              variable_type = "node"
              initial_value = ""
            } # current_events

            # The current_events_all_resources node keeps track of how many events there are right now, for each resource
            current_events_all_resources = {
              type = "variable"
              variable_name = "current_events_all_resources"
              variable_type = "node"
              initial_value = ""
            } # current_events_all_resources

            future_event_end_date_times = {
              type = "variable"
              variable_name = "future_event_end_date_times"
              variable_type = "node"
              initial_value = ""
            } # future_event_end_date_times

	    # This is the top-level node for future event information.  It has one subnode for each resource, or one called "GLOBAL" if only one resource is tracked.
            future_event_all_resources_end_date_times = {
              type = "variable"
              variable_name = "future_event_all_resources_end_date_times"
              variable_type = "node"
              initial_value = ""
            } # future_event_all_resources_end_date_times

            future_event = {
              type = "variable"
              variable_name = "future_event"
              variable_type = "node"
              initial_value = ""
            } # future_event

            end_date_time = {
              type = "variable"
              variable_name = "end_date_time"
              variable_type = "int"
              initial_value = ""
            } # end_date_time

            nodepos = {
              type = "variable"
              variable_name = "nodepos"
              variable_type = "int"
              initial_value = ""
            } # nodepos

            min = {
              type = "variable"
              variable_name = "min"
              variable_type = "int"
              initial_value = ""
            } # min

            max = {
              type = "variable"
              variable_name = "max"
              variable_type = "int"
              initial_value = ""
            } # max

            mid = {
              type = "variable"
              variable_name = "mid"
              variable_type = "int"
              initial_value = ""
            } # mid

            midVal = {
              type = "variable"
              variable_name = "midVal"
              variable_type = "int"
              initial_value = ""
            } # midVal

            keyfound = {
              type = "variable"
              variable_name = "keyfound"
              variable_type = "bool"
              initial_value = ""
            } # keyfound

          } # conditions

          # The follow expression is the code which implements the filter action  
          expression = `

{=
# Set future_event_date_times to future_event_all_resources_end_date_times for global analysis, or to a subnode of it for per-resource analysis.
if (@parameters{'track_per_resource'}{'parameter_value'}) then (
  'future_event_end_date_times = future_event_all_resources_end_date_times{' . @parameters{'resource_field'}{'parameter_value'} . '};\n';
  'current_events = current_events_all_resources{' . @parameters{'resource_field'}{'parameter_value'} . '};\n' .
);
else (
  'future_event_end_date_times = future_event_all_resources_end_date_times;\n' .
  'current_events = current_events_all_resources;\n'
);
=}

#echo("[" . {= @parameters{'resource_field'}{'parameter_value'} =} . "]: {= @parameters{'date_time_field'}{'parameter_value'} =}=" . {= @parameters{'date_time_field'}{'parameter_value'} =} . "; {= @parameters{'duration_field'}{'parameter_value'} =}=" . {= @parameters{'duration_field'}{'parameter_value'} =});

#echo("BEFORE: {= @parameters{'resource_field'}{'parameter_value'} =}=" . {= @parameters{'resource_field'}{'parameter_value'} =} . "; future_event_end_date_times=" . node_as_string(future_event_end_date_times));

# Pull all events off the front of the queue which are over, as of this timestamp.  For each, decrement current_events and remove it from the queue.
while ((num_subnodes(future_event_end_date_times) > 0) and (@(future_event_end_date_times[0]) < {= @parameters{'date_time_field'}{'parameter_value'} =})) (
#  echo("[" . {= @parameters{'resource_field'}{'parameter_value'} =} . "]: Closing: " . @future_event_end_date_times[0] . "; subtracting " . @(future_event_end_date_times[0]){"count"});
  @current_events -= @(future_event_end_date_times[0]){"count"};
  delete_node(future_event_end_date_times[0]);
);

# If duration is 0, don't count it as an event for concurrency calculations
if ({= @parameters{'duration_field'}{'parameter_value'} =} != 0) then (

#  echo("[" . {= @parameters{'resource_field'}{'parameter_value'} =} . "]: {= @parameters{'date_time_field'}{'parameter_value'} =}=" . {= @parameters{'date_time_field'}{'parameter_value'} =} . "; {= @parameters{'duration_field'}{'parameter_value'} =}=" . {= @parameters{'duration_field'}{'parameter_value'} =});

  # This is an event, so mark that we have one more event now
  @current_events = @current_events + 1;
#  echo("[" . {= @parameters{'resource_field'}{'parameter_value'} =} . "]: Started new event; now @current_events=" . @current_events);

  end_date_time = {= @parameters{'date_time_field'}{'parameter_value'} =} + {= @parameters{'duration_field'}{'parameter_value'} =};
#  echo('  end_date_time: ' . end_date_time);

  # Use a binary search to find this node
#  echo("Looking for " . end_date_time . " in " . node_as_string(future_event_end_date_times));
#  min = 0;
#  max = num_subnodes(future_event_end_date_times);
#  if (max != 0) then (
#    echo("starting with min=" . min . " and max=" . max);
#    nodepos = (min + max) / 2;
#    while ((min < max) and (end_date_time != @(future_event_end_date_times[nodepos]))) (
#      echo("searching at nodepos=" . nodepos . "; min=" . min . "; max=" . max . "; @(future_event_end_date_times[" . nodepos . "])=" . @(future_event_end_date_times[nodepos]));
#      if (end_date_time <= @(future_event_end_date_times[nodepos])) then (
#        max = nodepos - 1;
#        echo("Adjusted max; min=" . min . " and max=" . max);
#      );
#      else (
#        min = nodepos + 1;
#        echo("Adjusted min; min=" . min . " and max=" . max);
#      );
#      nodepos = (min + max) / 2;
#    );
#    #nodepos = (min + max) / 2;
#  ); # if non-empty

#  echo("Looking for " . end_date_time . " in " . node_as_string(future_event_end_date_times));
  min = 0;
  max = num_subnodes(future_event_end_date_times) - 1;
#  int min;
  nodepos = -1;
  keyfound = false;
  while (min < max) (
    nodepos = (min + max) / 2;
    midVal =  @(future_event_end_date_times[nodepos]);
#echo("min=" . min . "; max=" . max . "; midVal=" . midVal);
    if (midVal < end_date_time) then
      min = nodepos + 1;
    else if (midVal > end_date_time) then
      max = nodepos - 1;
    else (
#      nodepos = mid; # keyfound
      keyfound = true;
      max = min; # exit loop
    );
#echo("continuing with min=" . min . "; max=" . max);
  );

#echo("keyfound=" . keyfound);
  if (!keyfound) then (
    nodepos = min;
#echo("nodepos=" . nodepos);
    if (nodepos >= num_subnodes(future_event_end_date_times)) then (
    );
    else if (@(future_event_end_date_times[nodepos]) < end_date_time) then
      nodepos++;
#echo("Node not found; using nodepos=" . nodepos);
  );

#  if (midVal > end_date_time) then
#    nodepos

#  if (nodepos == -1) then
#    nodepos = min;


#echo("FOUND at nodepos=" . nodepos . "; min=" . min . "; max=" . max);

# If we found a node smaller than end_date_time, move up to the next one

# At this point, nodepos is the index of the node (0-indexed) we want to insert *before*; or it is num_subnodes(future_event_end_date_times) if we're adding to the end.

#echo("num_subnodes(future_event_end_date_times): " . num_subnodes(future_event_end_date_times));
#if (nodepos < num_subnodes(future_event_end_date_times)) then
#  echo("@(future_event_end_date_times[" . nodepos . "]): " . @(future_event_end_date_times[nodepos]));

# If this is a new node (if we didn't find this timestamp), create a new subnode with count=1
#  if (nodepos >= num_subnodes(future_event_end_date_times)) then (
#echo("Inserting new node at position " . nodepos);
#    future_event = new_node();
#    rename_node(future_event, thisrownum);
#    set_node_type(future_event, 'int');
#    @future_event = end_date_time;
#    @future_event{"count"} = 1;
#    insert_node(future_event_end_date_times, future_event, nodepos);
#  );

# If we found a node less than this one, but didn't find this node, insert a new node after it with count=1.
#if (@(future_event_end_date_times[nodepos]) != end_date_time) then (

# If we found a node smaller than end_date_time, move up to the next one
#if (@(future_event_end_date_times[nodepos]) < end_date_time) then
#  nodepos++;
if (!keyfound) then (

#echo("NOT FOUND, but can insert it at nodepos=" . nodepos);

#echo("Inserting new node at position " . nodepos);
    future_event = new_node();
    rename_node(future_event, thisrownum);
    set_node_type(future_event, 'int');
    @future_event = end_date_time;
    @future_event{"count"} = 1;
    insert_node(future_event_end_date_times, future_event, nodepos);
  );

# Otherwise, increment the count of the existing node
  else (
#echo("FOUND at nodepos=" . nodepos);
#echo("Incrementing node at position " . nodepos);
    @(future_event_end_date_times[nodepos]){"count"}++;
  );

#nodepos = 0;
#while ((nodepos < num_subnodes(future_event_end_date_times)) and (@(future_event_end_date_times[nodepos]) <= end_date_time))
#  nodepos++;

# Remember the end of this event
#set_node_type(future_event_end_date_times{thisrownum}, "int");
#@future_event_end_date_times{thisrownum} = {= @parameters{'date_time_field'}{'parameter_value'} =} + {= @parameters{'duration_field'}{'parameter_value'} =};

##echo("CHECKING SORT (" . num_subnodes(future_event_end_date_times) . ")");
#node testn;
#int lasttime = 0;
#foreach testn future_event_end_date_times (
##echo("consistency check: @testn=" . @testn . "; lasttime=" . lasttime . "; {= @parameters{'date_time_field'}{'parameter_value'} =}=" . {= @parameters{'date_time_field'}{'parameter_value'} =});
#  if (@testn < lasttime) then (
#    error("Internal: sort order check failed on " . node_as_string(future_event_end_date_times));
#  );
#  if (@testn < {= @parameters{'date_time_field'}{'parameter_value'} =}) then
#    error("Internal: date/time consistency check failed; date_time=" . {= @parameters{'date_time_field'}{'parameter_value'} =} . " but @testn=" . @testn . "; node=" . node_as_string(future_event_end_date_times));
##  echo("Sort confirmed for " . @testn);
#  lasttime = @testn;
#);
#echo("SORT/FUTURE CONSISTENCY CONFIRMED (" . num_subnodes(future_event_end_date_times) . " events)");

#echo("date_time=" . date_time . "; future_event_end_date_times: " . node_as_string(future_event_end_date_times));
#echo("AFTER: " . node_as_string(future_event_end_date_times));

); # if duration != 0

# Mark the number of events for this row
  {= @parameters{'concurrent_events_name'}{'final_node_name'} =} = @current_events;
#echo("[" . {= @parameters{'resource_field'}{'parameter_value'} =} . "]: Now @current_events=" . @current_events);

`
  
        } # concurrent_events_name
      } # filters
    } # add_sessions_database_filter

    # When attaching: Add the report field
    add_report_field = {
      type = "add_report_fields"
      fields = {      

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
          label = "{= @parameters{'concurrent_events_name'}{'parameter_value'} =}"
          column_label = ""
          column_info = ""
          database_field = "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}"
          display_format_type = "integer"
          show_remainder_value = true
          show_average_value = true
          show_min_value = true
          show_max_value = true
          show_total_value = true
          percent_calculation = "sum"
        } # concurrent_events_name

      } # fields
    } # add_report_field

    # When attaching: Add the report field to all xref groups
    add_xref_field = {
      type = "add_xref_fields"
      xref_group = "*"
      fields = {
        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = ""
      } # fields
    } # add_xref_field

    # When attaching: Add the column to overview
    add_report_column_overview = {
      type = "add_report_element_columns"
      report = "overview"
      report_element = "overview"
      columns = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
          report_field = "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}"
          show_column = true
          show_percent_column = false
          show_bar_column = false
          show_graph = false
        } # concurrent_events_name

      } # columns
    } # add_report_columns

    # When attaching: Add the column to day
    add_report_column_day = {
      type = "add_report_element_columns"
      report = "day"
      report_element = "day"
      columns = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
          report_field = "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}"
          show_column = true
          show_percent_column = false
          show_bar_column = false
          show_graph = false
        } # concurrent_events_name

      } # columns
    } # add_report_columns_day

    # When attaching: Add the column to month
    add_report_column_month = {
      type = "add_report_element_columns"
      report = "month"
      report_element = "month"
      columns = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
          report_field = "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}"
          show_column = true
          show_percent_column = false
          show_bar_column = false
          show_graph = false
        } # concurrent_events_name

      } # columns
    } # add_report_columns_month

    # When attaching: Add the column to year
    add_report_column_year = {
      type = "add_report_element_columns"
      report = "year"
      report_element = "year"
      columns = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
          report_field = "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}"
          show_column = true
          show_percent_column = false
          show_bar_column = false
          show_graph = false
        } # concurrent_events_name

      } # columns
    } # add_report_columns_year

    # When attaching: Add the column to hour_of_day
    add_report_column_hour_of_day = {
      type = "add_report_element_columns"
      report = "hour_of_day"
      report_element = "hour_of_day"
      columns = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
          report_field = "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}"
          show_column = true
          show_percent_column = false
          show_bar_column = false
          show_graph = false
        } # concurrent_events_name

      } # columns
    } # add_report_columns_hour_of_day

    # When attaching: Add the column to day_of_week
    add_report_column_day_of_week = {
      type = "add_report_element_columns"
      report = "day_of_week"
      report_element = "day_of_week"
      columns = {

        "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}" = {
          report_field = "{= @parameters{'concurrent_events_name'}{'final_node_name'} =}"
          show_column = true
          show_percent_column = false
          show_bar_column = false
          show_graph = false
        } # concurrent_events_name

      } # columns
    } # add_report_columns_day_of_week

  } # attach_operations
  
} # concurrent_events