#!/bin/bash

run_qml() {
	local script=$1 dir=$2
	shift 2

	case $dir in
		/*)
			;;
		*)
			dir=./$dir
	esac

	# One may complain about JSON, but figuring out how QML parses non-JSON
	# argument strings is likely to be an exercise in pain by comparison.
	kid3-cli -c "$(
		printf '%s\0' "$script" "$@" |
		jq -Rsc '{ method: "execute", params: (["@qml"] + (split("\u0000")[:-1])) }'
	)" "$dir"
}

# /dir appears to prime the script for methods such as app.firstFile(),
# app.nextFile(), app.getFrame(), app.setFrame() and such. To access
# optional_args, use getArguments().
run_qml /path/to/qml /dir # optional_args...