#!/usr/bin/env bash
#
# monitor.sh -- Open the serial monitor
#
# Reads baud rate from .anvil.toml. No Anvil binary required.
#
# Usage:
#   ./monitor.sh                    Auto-detect port
#   ./monitor.sh -p /dev/ttyUSB0    Specify port
#   ./monitor.sh -b 9600            Override baud rate
#   ./monitor.sh --watch            Reconnect after reset/replug
#
# Prerequisites: arduino-cli in PATH

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
CONFIG="$SCRIPT_DIR/.anvil.toml"

# -- Colors ----------------------------------------------------------------
if [[ -t 1 ]]; then
    RED=$'\033[0;31m'; GRN=$'\033[0;32m'; YLW=$'\033[0;33m'
    CYN=$'\033[0;36m'; BLD=$'\033[1m';    RST=$'\033[0m'
else
    RED=''; GRN=''; YLW=''; CYN=''; BLD=''; RST=''
fi

warn() { echo "${YLW}warn${RST} $*"; }
die()  { echo "${RED}FAIL${RST} $*" >&2; exit 1; }

# -- Parse .anvil.toml -----------------------------------------------------
[[ -f "$CONFIG" ]] || die "No .anvil.toml found in $SCRIPT_DIR"

toml_get() {
    (grep "^$1 " "$CONFIG" 2>/dev/null || true) | head -1 | sed 's/.*= *"\{0,1\}\([^"]*\)"\{0,1\}/\1/' | tr -d ' '
}

BAUD="$(toml_get 'baud')"
BAUD="${BAUD:-115200}"
DEFAULT_PORT="$(toml_get 'port')"

# -- Parse arguments -------------------------------------------------------
PORT=""
DO_WATCH=0

while [[ $# -gt 0 ]]; do
    case "$1" in
        -p|--port)  PORT="$2"; shift 2 ;;
        -b|--baud)  BAUD="$2"; shift 2 ;;
        --watch)    DO_WATCH=1; shift ;;
        -h|--help)
            echo "Usage: ./monitor.sh [-p PORT] [-b BAUD] [--watch]"
            echo "  Opens serial monitor. Baud rate from .anvil.toml."
            exit 0
            ;;
        *) die "Unknown option: $1" ;;
    esac
done

# -- Preflight -------------------------------------------------------------
command -v arduino-cli &>/dev/null \
    || die "arduino-cli not found in PATH."

# -- Auto-detect port ------------------------------------------------------
auto_detect() {
    # Prefer ttyUSB/ttyACM (real USB devices) over ttyS (hardware UART)
    local port
    port=$(arduino-cli board list 2>/dev/null \
        | grep -i "serial" \
        | awk '{print $1}' \
        | grep -E 'ttyUSB|ttyACM|COM' \
        | head -1)

    # Fallback: any serial port
    if [[ -z "$port" ]]; then
        port=$(arduino-cli board list 2>/dev/null \
            | grep -i "serial" \
            | head -1 \
            | awk '{print $1}')
    fi

    echo "$port"
}

if [[ -z "$PORT" ]]; then
    # Check .anvil.toml for configured port
    if [[ -n "$DEFAULT_PORT" ]]; then
        PORT="$DEFAULT_PORT"
    else
        PORT="$(auto_detect)"
    fi

    if [[ -z "$PORT" ]]; then
        die "No serial port detected. Is the board plugged in?\n  Specify manually: ./monitor.sh -p /dev/ttyUSB0\n  Or set port in .anvil.toml"
    fi
    warn "Auto-detected port: $PORT (use -p to override)"
fi

# -- Watch mode ------------------------------------------------------------
if [[ $DO_WATCH -eq 1 ]]; then
    echo "${CYN}${BLD}Persistent monitor on ${PORT} at ${BAUD} baud${RST}"
    echo "Reconnects after upload / reset / replug."
    echo "Press Ctrl+C to exit."
    echo ""

    trap "echo ''; echo 'Monitor stopped.'; exit 0" INT

    while true; do
        if [[ -e "$PORT" ]]; then
            arduino-cli monitor -p "$PORT" -c "baudrate=$BAUD" 2>/dev/null || true
            echo "${YLW}--- ${PORT} disconnected ---${RST}"
        else
            echo "${CYN}--- Waiting for ${PORT} ...${RST}"
            while [[ ! -e "$PORT" ]]; do
                sleep 0.5
            done
            sleep 1
            echo "${GRN}--- ${PORT} connected ---${RST}"
        fi
        sleep 0.5
    done
else
    echo "Opening serial monitor on $PORT at $BAUD baud..."
    echo "Press Ctrl+C to exit."
    echo ""
    arduino-cli monitor -p "$PORT" -c "baudrate=$BAUD"
fi