#!/bin/bash
#
# detect-device.sh - Detect which doorbell board is connected
#
# Uses two methods:
# 1. Firmware query (if flashed): sends "board" command, expects "[BOARD] xxx"
# 2. Hardware probe (fallback): uses esptool to query chip type and flash size
#
# Usage: ./scripts/detect-device.sh [port]
#   If no port specified, tries common ports: /dev/ttyUSB0 /dev/ttyACM0

set -e

# Configuration
TIMEOUT_FIRMWARE=2
TIMEOUT_HARDWARE=5

# Known boards and their characteristics
declare -A BOARD_CHIP=(
    ["esp32-s3-lcd-43"]="ESP32-S3"
    ["esp32-32e"]="ESP32"
    ["esp32-32e-4"]="ESP32"
)

# Find available serial ports
find_ports() {
    local ports=()
    for p in /dev/ttyUSB0 /dev/ttyUSB1 /dev/ttyACM0 /dev/ttyACM1; do
        if [ -e "$p" ]; then
            ports+=("$p")
        fi
    done
    printf '%s\n' "${ports[@]}"
}

# Query firmware for board name
query_firmware() {
    local port="$1"
    
    # Try using Python for more reliable serial communication
    local output
    output=$(python3 -c "
import serial
import time
try:
    s = serial.Serial('$port', 115200, timeout=$TIMEOUT_FIRMWARE)
    time.sleep(0.5)
    s.write(b'board\r\n')
    time.sleep($TIMEOUT_FIRMWARE)
    print(s.read(200).decode('utf-8', errors='ignore'))
    s.close()
except:
    pass
" 2>/dev/null || true)
    
    # Look for [BOARD] xxx pattern
    if echo "$output" | grep -q '\[BOARD\]'; then
        local board
        board=$(echo "$output" | grep '\[BOARD\]' | sed 's/.*\[BOARD\] //' | tr -d '\r\n')
        if [ -n "$board" ]; then
            echo "$board"
            return 0
        fi
    fi
    return 1
}

# Hardware probe using esptool
probe_hardware() {
    local port="$1"
    
    # Get chip info
    local chip_info
    chip_info=$(timeout "$TIMEOUT_HARDWARE" esptool --port "$port" chip_id 2>/dev/null || true)
    
    if [ -z "$chip_info" ]; then
        return 1
    fi
    
    # Check for ESP32-S3
    if echo "$chip_info" | grep -q "ESP32-S3"; then
        echo "esp32-s3-lcd-43"
        return 0
    fi
    
    # For ESP32, check flash size
    if echo "$chip_info" | grep -q "ESP32"; then
        local flash_size
        flash_size=$(echo "$chip_info" | grep -i "flash size" | grep -oE '[0-9]+' | head -1 || echo "0")
        
        if [ -n "$flash_size" ] && [ "$flash_size" -ge 8 ]; then
            # 8MB+ flash - likely esp32-32e-4
            echo "esp32-32e-4 (or esp32-32e)"
            return 0
        else
            # 4MB or less - likely esp32-32e
            echo "esp32-32e (or esp32-32e-4)"
            return 0
        fi
    fi
    
    return 1
}

# Main detection logic
detect() {
    local port="$1"
    
    # Try firmware query first (100% accurate if firmware responds)
    echo "Trying firmware query on $port..." >&2
    local result
    result=$(query_firmware "$port" || true)
    
    if [ -n "$result" ]; then
        echo "Detected via firmware: $result"
        return 0
    fi
    
    # Fall back to hardware probe
    echo "Trying hardware probe on $port..." >&2
    result=$(probe_hardware "$port" || true)
    
    if [ -n "$result" ]; then
        echo "Detected via hardware: $result"
        return 0
    fi
    
    echo "No device detected on $port" >&2
    return 1
}

# Entry point
main() {
    local target_port="$1"
    
    if [ -n "$target_port" ]; then
        # Specific port requested
        if [ ! -e "$target_port" ]; then
            echo "Error: Port $target_port does not exist" >&2
            exit 1
        fi
        detect "$target_port"
    else
        # Auto-detect: try all available ports
        local found=0
        for port in $(find_ports); do
            if detect "$port"; then
                found=1
                break
            fi
        done
        
        if [ "$found" -eq 0 ]; then
            echo "No doorbell device detected" >&2
            exit 1
        fi
    fi
}

main "$@"