#!/usr/bin/env bash
# Launch the built DOS example in DOSBox. Defaults to PATTERN.
#
#   scripts/run-dos.sh           # runs PATTERN
#   scripts/run-dos.sh hello     # runs HELLO
#   scripts/run-dos.sh draw      # runs DRAW
#
# Argument is any built example name (case-insensitive); the script
# upper-cases it and appends .EXE, then checks the file exists.

set -euo pipefail

if [[ $# -gt 1 ]]; then
    echo "usage: $0 [example-name]" >&2
    exit 2
fi

prog=${1:-pattern}
repo=$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)
bin_dir=$repo/build/dos/bin
conf=$repo/scripts/dosbox-386sx16.conf
file=${prog^^}.EXE

if [[ ! -f "$bin_dir/$file" ]]; then
    echo "$bin_dir/$file not built. Run 'make dos' first." >&2
    if compgen -G "$bin_dir/*.EXE" > /dev/null; then
        echo "available examples in $bin_dir:" >&2
        ls "$bin_dir"/*.EXE | xargs -n1 basename >&2
    fi
    exit 1
fi

# mouse_capture=seamless is required for DOSBox-Staging when running
# inside a VM whose host already manages the pointer; without it the
# default capture-on-click behavior fights the VM's grab and mouse
# input is unusable. On plain DOSBox this -set flag is unknown and is
# logged once as a warning, then ignored -- harmless either way.
#
# -conf $conf locks the CPU to a simulated 386SX-16 (the slowest
# realistic 386 desktop). DOSBox layers configs: anything not set in
# our file falls back to the user's main dosbox.conf.
exec dosbox \
    -conf "$conf" \
    -set "mouse_capture=seamless" \
    -c "C:" \
    -c "$file" \
    -c "pause" \
    --exit "$bin_dir"