#!/usr/bin/env bash
# Builds/flashes for a specific board variant. This project targets two:
#
#   devkit  ESP32-C6-DevKitC-1 (8MB flash) -- the dev board. This is
#           also the plain `idf.py` default (sdkconfig/build/), so this
#           script's devkit mode is mostly for symmetry -- normal
#           `idf.py build`/`flash` work fine too.
#   xiao    Seeed XIAO ESP32-C6 (4MB flash) -- the production board.
#
# The two need different partition tables (the XIAO's 4MB doesn't fit
# the dev board's two 2MB OTA app slots -- see partitions_xiao.csv,
# 1.875MB slots instead) and a different flash-size Kconfig. Rather
# than hand-editing the shared sdkconfig back and forth (fragile, easy
# to leave it in the wrong state for whichever board you flash next),
# each board gets its own build directory and its own generated
# sdkconfig, seeded from sdkconfig.defaults (shared) with the board's
# override file layered on top via ESP-IDF's own SDKCONFIG_DEFAULTS
# mechanism. Switching boards is just switching which one you invoke --
# neither ever touches the other's config or build output.
#
# Usage:
#   ./build_for_board.sh xiao build
#   ./build_for_board.sh xiao flash -p /dev/ttyUSB0
#   ./build_for_board.sh xiao flash monitor -p /dev/ttyUSB0
#   ./build_for_board.sh devkit build
#
# Defaults to "build" if no idf.py subcommand is given.

set -euo pipefail

script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
cd "$script_dir"

if [ $# -lt 1 ]; then
    echo "Usage: $0 <devkit|xiao> [idf.py args...]" >&2
    exit 1
fi
board="$1"
shift

case "$board" in
    xiao)
        build_dir="$script_dir/build_xiao"
        sdkconfig_path="$script_dir/sdkconfig.xiao_local"
        defaults="$script_dir/sdkconfig.defaults;$script_dir/sdkconfig.xiao"
        ;;
    devkit)
        build_dir="$script_dir/build"
        sdkconfig_path="$script_dir/sdkconfig"
        defaults="$script_dir/sdkconfig.defaults"
        ;;
    *)
        echo "Unknown board '$board' -- expected 'devkit' or 'xiao'" >&2
        exit 1
        ;;
esac

args=("$@")
if [ ${#args[@]} -eq 0 ]; then
    args=(build)
fi

# idf.py is normally a shell *function* (defined by ESP-IDF's
# activate/export script), not a real executable on PATH -- that
# function isn't inherited by this script's own subshell even if you
# sourced the activation script first. IDF_PATH (an exported env var,
# which *is* inherited) lets this work the same way regardless: call
# the underlying Python module directly.
if [ -z "${IDF_PATH:-}" ]; then
    echo "IDF_PATH is not set -- source your ESP-IDF activation/export.sh first" >&2
    exit 1
fi

echo "==> Board: $board (build dir: $(basename "$build_dir"), sdkconfig: $(basename "$sdkconfig_path"))"
exec python "$IDF_PATH/tools/idf.py" -B "$build_dir" -D "SDKCONFIG=$sdkconfig_path" -D "SDKCONFIG_DEFAULTS=$defaults" "${args[@]}"