#!/bin/bash

# ============================================================================
# flash.sh - Flash firmware to the Raspberry Pi Pico
# ============================================================================
# This script MUST run on the host macOS (not inside Docker) because it
# needs access to /Volumes/RPI-RP2, the USB mass storage mount point that
# appears when the Pico is held in BOOTSEL mode during power-on.
#
# Usage:
#   1. Hold BOOTSEL on the Pico and plug it into USB
#   2. Run: ./flash.sh
#
# Or chain with a build:
#   docker compose run --rm pico-build bash build.sh && ./flash.sh
# ============================================================================

PICO_MOUNT="/Volumes/RPI-RP2"
UF2_FILE="build/Color_Switcher_PICO.uf2"

# Verify the firmware file exists before waiting for the Pico
if [ ! -f "$UF2_FILE" ]; then
    echo "Error: $UF2_FILE not found. Run the build first:"
    echo "  docker compose run --rm pico-build bash build.sh"
    exit 1
fi

# Wait for the Pico to appear in BOOTSEL mode
echo "Waiting for Pico in BOOTSEL mode ($PICO_MOUNT)..."
echo "  -> Hold BOOTSEL and plug in the Pico via USB"
while [ ! -d "$PICO_MOUNT" ]; do
    sleep 0.5
done

# Copy the firmware to the Pico's USB mass storage
echo "Pico detected. Copying $UF2_FILE..."
cp "$UF2_FILE" "$PICO_MOUNT/"

# Wait for the Pico to unmount (it reboots automatically after receiving the .uf2)
echo "Waiting for Pico to reboot..."
while [ -d "$PICO_MOUNT" ]; do
    sleep 0.5
done

echo "Done! Pico rebooted with new firmware."
echo "  -> Open a serial monitor: screen /dev/tty.usbmodem* 115200"