Lich Triggers

(Work in Progress)

Introduction

The concept of triggers is that Lich will respond automatically to certain game output without the need to run a separate script. Historically, the ability to set triggers is a function of the Front End being used. Lich-based triggers are front-end agnostic and built within Lich itself. Thus, they can be used across and between front ends. Simple triggers have a fairly low barrier to entry for users, and more advanced uses can allow some complex handling without writing a dedicated script. Further, triggers can supplement the use of curated or custom Lich scripts. At some point, though, the complexity of an action calls for writing a dedicated script.

Underlying Code Structure

Lich's triggers are defined by the user in a yaml file along with the desired trigger responses. Triggers are then monitored for and acted upon with a persistent companion script called trigger-watcher. Fundamentally, Lich's triggers use class Flags which is defined in the events script and at a basic level monitor for user-defined game output. In order for Lich triggers to work, triggers must be defined properly in the yaml, and both the events and trigger-watcher script must stay running.

Structure of a Trigger

The structure of each trigger is as follows:

• The top level heading of lich_triggers (required)
• Beneath that and indented, the name of this specific trigger. This is arbitrary -- name it what you want.
• Beneath that and indented, a section called triggers:. This represents the game output you want the trigger to look for and then take action.
• Beneath that and indented, a section called responses:. When Lich sees the output you defined in the triggers section, it will process these trigger responses.

Let's look at an extremely simple trigger.

# LICH TRIGGERS
# Yaml for Lich-based triggers

lich_triggers:
  wave_hello:
    triggers:
      - Bobafett just arrived
    responses:
      - wave Bobafett

This trigger recognizes when a character named Bobafett enters the room, and it waves to them. What's happening behind the scenes is that Lich is watching all game output lines for Bobafett just arrived. When it sees that, it takes the action you've defined in responses and it will send wave Bobafett as a game input command.

Getting Started

Only two things are necessary to be up and running with triggers:

1. Define your triggers in a lich_triggers: section in your Charname-setup.yaml or set them up in a separate file named Charname-triggers.yaml. Both ways are supported.
2. Run the trigger-watcher script. It's recommended to add this to your autostarts.

Some Finer Details

Within a single trigger name, you can specify multiple triggers and multiple responses. Here are some simple examples:

# LICH TRIGGERS
# Yaml for Lich-based triggers

lich_triggers:
  wave_hello:
    triggers:
      - Bobafett just arrived
      - Hansolo just arrived
    responses:
      - wave

Here we've specified two different triggers, and modified our response slightly. If Lich sees game output of either Bobafett just arrived OR Hansolo just arrived, it will trigger a response of game input wave.

# LICH TRIGGERS
# Yaml for Lich-based triggers

lich_triggers:
  wave_hello:
    triggers:
      - Bobafett just arrived
    responses:
      - wave Bobafett
      - kick Bobafett

Here we've specified a single trigger but two responses. If Lich sees Bobafett enter the room, it will send the two responses as game commands one right after the other: wave Bobafett and kick Bobafett.

Trigger Commands

A set of trigger commands is provided for use by the user. These commands tell Lich treat trigger responses in various ways. Commands are always preceded by the = sign, which tells Lich to run it as a trigger command. Trigger response lines must begin with these commands to be properly parsed.

Trigger Command	Description	Example	Notes
=exec	Execute a script.	=exec <script> [arguments]
=execw	Execute a script and wait to complete the script before moving on.	=execw <script> [arguments]
=eval	Evaluate as Lich/Ruby code.	=eval DRC.message("hello")
=uvar	Set or delete a Lich User Variable.	=uvar set MyUserVariable 22 =uvar delete MyUserVariable	You can reference a stored user variable in your triggers via $UserVarName.
=logf	Log to a file.	=logf <filename> <text to log>	Creates the file if it doesn't exist. Appends the data if it does. Includes a timestamp.
=logw	Log to a window.	=logw <windowname> <text to log>	Creates the window if it doesn't exist. Includes a timestamp.
=pause	Pause a specified amount of seconds.	=pause 10
=if =elsif =else	Allow if, elsif, else functionality.	=if {3 > 2} {DRC.message("true")} =else {DRC.message("else")}	Can have multiple actions for each if/elsif/else. Can have multiple elsif's. Nesting of these commands not currently supported, but valid Ruby works within them. Note the use of curly brackets, which are required.

Regex and Regex/UserVar Substitutions

Triggers support regex and trigger responses support regex substitutions and Lich UserVar substitutions.

To use regex substitutions, use capture groups in your trigger and reference them via $1 through $9. You are limited to 9 regex substitutions. Named capture groups are not currently supported.

lich_triggers:
  regex_sub_test:
    triggers:
      - You are (.*) years old
    responses:
      - say I am $1

>age
You are one hundred twenty-seven years old.
Among Elves, you are considered an adult.
To the other races, you appear to be young.
You are aging at a normal rate for an Elf.
[Type AGE HELP for more options.]
>
[trigger-watcher]>say I am one hundred twenty-seven
You say, "I am one hundred twenty-seven."

To use UserVar substitutions, use the same $ character and reference the UserVar by its name. The first character in a UserVar cannot be a number. Otherwise, no limitations on the name.

NOTE: If you're using regex substitution, use only a single trigger line.