#!/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}"
LOCAL_CONFIG="$SCRIPT_DIR/.anvil.local"
LOCAL_PORT=""
LOCAL_VID_PID=""
if [[ -f "$LOCAL_CONFIG" ]]; then
    LOCAL_PORT="$(grep '^port ' "$LOCAL_CONFIG" 2>/dev/null | head -1 | sed 's/.*= *"\{0,1\}\([^"]*\)"\{0,1\}/\1/' | tr -d ' ')"
    LOCAL_VID_PID="$(grep '^vid_pid ' "$LOCAL_CONFIG" 2>/dev/null | head -1 | sed 's/.*= *"\{0,1\}\([^"]*\)"\{0,1\}/\1/' | tr -d ' ')"
fi

# -- 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"
}

# resolve_vid_pid VID:PID -- search arduino-cli JSON for matching device
resolve_vid_pid() {
    local target_vid target_pid json
    target_vid="$(echo "$1" | cut -d: -f1 | tr '[:upper:]' '[:lower:]')"
    target_pid="$(echo "$1" | cut -d: -f2 | tr '[:upper:]' '[:lower:]')"
    json="$(arduino-cli board list --format json 2>/dev/null)" || return
    echo "$json" | python3 -c "
import sys, json
try:
    data = json.load(sys.stdin)
    for dp in data.get('detected_ports', []):
        port = dp.get('port', {})
        if port.get('protocol') != 'serial':
            continue
        props = port.get('properties', {})
        vid = props.get('vid', '').lower().replace('0x', '')
        pid = props.get('pid', '').lower().replace('0x', '')
        if vid == '$target_vid' and pid == '$target_pid':
            print(port.get('address', ''))
            break
except: pass
" 2>/dev/null
}

if [[ -z "$PORT" ]]; then
    # Try VID:PID resolution first
    if [[ -n "$LOCAL_VID_PID" ]]; then
        PORT="$(resolve_vid_pid "$LOCAL_VID_PID")"
        if [[ -n "$PORT" ]]; then
            if [[ "$PORT" != "$LOCAL_PORT" ]] && [[ -n "$LOCAL_PORT" ]]; then
                warn "Device $LOCAL_VID_PID found on $PORT (moved from $LOCAL_PORT)"
            else
                warn "Using port $PORT (from .anvil.local)"
            fi
        fi
    fi

    # Fall back to saved port
    if [[ -z "$PORT" ]] && [[ -n "$LOCAL_PORT" ]]; then
        PORT="$LOCAL_PORT"
        warn "Using port $PORT (from .anvil.local)"
    fi

    # Fall back to auto-detect
    if [[ -z "$PORT" ]]; then
        PORT="$(auto_detect)"

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