#!/bin/bash
# ======================================================================
#  shutterlinksort
#  ----------------
#  Camera image downloader and organizer for PTP/IP-connected devices.
#
#  Connects to a camera over network (using gphoto2), downloads new
#  photos, extracts EXIF metadata (date, shutter count), and sorts
#  images into folders by date.
#
#  Usage:
#      shutterlinksort
#  Dependencies:
#      gphoto2, exiftool, bash
#
#  Author: James Blackmore (reclusejay)
#  Version: 1.0
# ======================================================================

# --- Safety options ---
# -e  : Exit immediately if a command exits with non-zero status.
# -u  : Treat unset variables as an error and exit.
# -o pipefail : Fail a pipeline if *any* command in it fails.
set -euo pipefail

# ============================================================
# Cleanup handler — runs on interrupt/termination
# ============================================================
cleanup() {
    # Disable any special globbing options we enabled
    shopt -u nullglob nocaseglob || true

    # Delete any 0-byte (incomplete) downloads if present
    find "$cam_dl_dir" -type f -size 0 -delete 2>/dev/null || true

    log "Caught interrupt, exiting"
    exit 0
}
# Trap cleanup on Ctrl+C, kill, or quit signals
trap cleanup SIGINT SIGTERM SIGQUIT

# ============================================================
# Function: php_get
# Pulls a config value from the PHP $CONFIG array
# ============================================================
php_get() {
    if ! command -v php >/dev/null 2>&1; then
        # fallback to php-cli
        if command -v php-cli >/dev/null 2>&1; then
            php-cli -r "include('../src/includes/config.php'); print \$CONFIG['$1'];"
        else
            echo "Error: Neither 'php' nor 'php-cli' is available."
            exit 1
        fi
    else
        php -r "include('../src/includes/config.php'); print \$CONFIG['$1'];"
    fi
    return 0    
}

# ============================================================
# Load all settings from PHP config
# ============================================================
cam_uuid=$(php_get "camera_uuid")
cam_dl_dir=$(php_get "upload_dir")
cam_sort_dir=$(php_get "sorted_img_dir")
cam_index_file=$(php_get "index_file")
cam_xml_url=$(php_get "camera_xml_url")
cam_ext_format=$(php_get "camera_ext_formats")
cam_mac=$(php_get "camera_mac")
g2_port=$(php_get "gphoto2_config_port")
g2_model=$(php_get "gphoto2_config_model")
g2_guid=$(php_get "gphoto2_config_guid")
g2_conf=$(php_get "gphoto2_config_file")

# Create the index file if missing
[ -f "$cam_index_file" ] || echo 0 > "$cam_index_file"

# ============================================================
# Global variables
# ============================================================
debug=true
ver="v.25.10.1"
STATUS="INITIALIZING"
CAM_IP=""

# ============================================================
# Function: log
# Provides timestamped console and syslog logging
# ============================================================
log() {
    local msg lev full_msg
    if $debug; then
        msg="${1:-NO MESSAGE!}"
        lev="${2:-info}"

        full_msg="[debug $lev] Version: $ver - $(date +[%Y/%m/%d-%H:%M:%S]) - $msg"

        # Always print to stdout for debugging
        echo "$full_msg"

        # Try syslog first; fallback to a file log if logger fails
        logger -t camera-download-sort "$full_msg" 2>/dev/null || \
        echo "$full_msg" >> /var/log/camera-download-sort.log
    fi
}

# ============================================================
# Function: find_ip_by_mac
# Locates the IP address of a device by its MAC address
# ============================================================
find_ip_by_mac() {
    local mac ip file

    # Normalize MAC to lowercase for comparison
    mac=$(echo "$1" | tr '[:upper:]' '[:lower:]')
    [ -z "$mac" ] && log "No MAC provided" && return 1

    # 1️⃣ Primary source: /proc/net/arp (most reliable)
    ip=$(awk -v mac="$mac" 'NR>1 && tolower($4)==mac {print $1; exit}' /proc/net/arp)

    # 2️⃣ Fallback: BusyBox arp command output
    if [ -z "$ip" ] && command -v arp >/dev/null 2>&1; then
        ip=$(arp | awk -v mac="$mac" 'NR>1 && tolower($4)==mac {print $1; exit}')
    fi

    # 3️⃣ Fallback: dnsmasq lease files
    if [ -z "$ip" ]; then
        for file in /tmp/dhcp.leases /var/lib/misc/dnsmasq.leases; do
            [ -f "$file" ] || continue
            ip=$(awk -v mac="$mac" 'tolower($2)==mac {print $3; exit}' "$file")
            [ -n "$ip" ] && break
        done
    fi

    # If found, set global CAM_IP variable
    if [ -n "$ip" ]; then
        CAM_IP="$ip"
        log "Camera found at $CAM_IP"
        return 0
    fi

    # Not found
    return 1
}

# ============================================================
# Function: is_camera_connected
# Checks whether the camera’s MAC address is visible
# ============================================================
is_camera_connected() {
    if find_ip_by_mac "$cam_mac"; then
        if [ "$STATUS" = "WAITING" ]; then
            # Already in waiting state — skip
            return 1
        fi
        STATUS="CONNECTED"
        return 0
    fi
    STATUS="DISCONNECTED"
    return 1
}

# ============================================================
# Function: download_images
# Uses gphoto2 (PTP/IP) to pull new images from camera
# ============================================================
download_images() {
    local wd="$PWD"
    STATUS="WAITING"
    cd "$cam_dl_dir" || return 1

    # Create gphoto2 config file if it doesn’t exist
    if [ ! -f "$g2_conf" ]; then
        {
            echo "$g2_port$CAM_IP"
            echo "$g2_model"
            echo "$g2_guid$cam_uuid"
        } > "$g2_conf"
    fi

    # Check for gphoto2 availability
    if command -v gphoto2 >/dev/null 2>&1; then
        # Download all new files, skipping ones that already exist
        if gphoto2 --port "ptpip:$CAM_IP" -P --skip-existing; then
            log "Downloaded new images from $CAM_IP"
            cd "$wd" || true
            return 0
        fi
        log "gphoto2 download failed" error
    else
        log "gphoto2 not found — skipping download" warn
    fi

    cd "$wd" || true
    return 1
}

# ============================================================
# Function: sort_images
# Sorts downloaded images into folders by EXIF date
# ============================================================
sort_images() {
    local ext img datetime shuttercount yyyy mm dd timepart hhmmss ext_lower \
          output_dir new_filename new_file uid index

    STATUS="SORTING"
    log "$STATUS"

    # Ensure exiftool exists
    command -v exiftool >/dev/null 2>&1 || {
        log "exiftool missing — cannot sort" error
        return 1
    }

    # Get current image index number
    index=$(cat "$cam_index_file")

    # Loop over each configured image extension (e.g. JPG ARW)
    for ext in $cam_ext_format; do
        # Enable flexible globbing (case-insensitive, no literal fail)
        shopt -s nullglob nocaseglob

        # Iterate through each matching file
        for img in "$cam_dl_dir"/*."$ext"; do

            # Pull EXIF date and shutter count
            readarray -t exif_data < <(exiftool -s -s -s -DateTimeOriginal -ShutterCount "$img")
            datetime="${exif_data[0]:-0000:00:00 00:00:00}"
            shuttercount="${exif_data[1]:-}"

            log "Processing $img (index $index)"

            # Generate a unique ID if no shuttercount found
            if [ -z "$shuttercount" ]; then
                uid="rn${RANDOM}idx${index}"
                log "No shuttercount in $img, uid=$uid"
            else
                uid="sc${shuttercount}idx${index}"
                log "Shuttercount=$shuttercount uid=$uid"
            fi

            # Parse EXIF date into components
            yyyy=$(echo "$datetime" | cut -d':' -f1)
            mm=$(echo "$datetime" | cut -d':' -f2)
            dd=$(echo "$datetime" | cut -d':' -f3 | cut -d' ' -f1)
            timepart=$(echo "$datetime" | cut -d' ' -f2)
            hhmmss=$(echo "$timepart" | tr -d ':')

            # Normalize extension to lowercase
            ext_lower=${ext,,}

            # Build destination folder structure
            output_dir="$cam_sort_dir/$ext_lower/$yyyy/$mm/$dd"
            mkdir -p "$output_dir" || { log "mkdir failed: $output_dir" error; return 1; }

            # Construct new filename
            new_filename="${hhmmss}_${uid}.${ext_lower}"
            new_file="$output_dir/$new_filename"

            log "Moving $img -> $new_file"

            # Move and increment index
            if mv "$img" "$new_file"; then
                index=$((index + 1))
            else
                log "Failed to move $img" error
            fi
        done

        # Update index file after processing each extension type
        printf '%s\n' "$index" > "$cam_index_file"
    done

    STATUS="DONE"
    log "$STATUS"
    return 0
}

# ============================================================
# Main loop — runs forever
# ============================================================
log "Camera script started"

while :; do
    # If camera detected and not already downloading/sorting
    if is_camera_connected && [ "$STATUS" != "WAITING" ] && [ "$STATUS" != "SORTING" ]; then
        download_images || log "Download step failed" error
    # If camera disconnected, begin sorting
    elif [ "$STATUS" = "DISCONNECTED" ]; then
        sort_images || log "Sort step failed" error
    fi

    # Avoid hammering system; check every 2 seconds
    sleep 2
done