#!/usr/bin/env bash
set -euo pipefail

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
CYAN='\033[0;36m'
NC='\033[0m'

info()   { echo -e "${GREEN}[+]${NC} $*"; }
warn()   { echo -e "${YELLOW}[!]${NC} $*"; }
die()    { echo -e "${RED}[ERROR]${NC} $*" >&2; exit 1; }
header() { echo -e "\n${CYAN}══════════════════════════════════════════${NC}"; echo -e "${CYAN}  $*${NC}"; echo -e "${CYAN}══════════════════════════════════════════${NC}"; }

ST_URL="http://127.0.0.1:8384"
APIKEY=""

get_apikey() {
    local container
    container=$(docker ps --format '{{.Names}}' | grep -i syncthing | head -1 || true)
    [ -n "$container" ] || die "No running Syncthing container found."
    APIKEY=$(docker exec "$container" cat /var/syncthing/config/config.xml 2>/dev/null | grep -oP '(?<=<apikey>)[^<]+' || true)
    [ -n "$APIKEY" ] || die "Could not read Syncthing API key from container '$container'."
}

st_get() {
    curl -sf -H "X-API-Key: $APIKEY" "${ST_URL}${1}"
}

st_post() {
    curl -sf -X POST -H "X-API-Key: $APIKEY" -H "Content-Type: application/json" -d "$2" "${ST_URL}${1}"
}

st_put() {
    curl -sf -X PUT -H "X-API-Key: $APIKEY" -H "Content-Type: application/json" -d "$2" "${ST_URL}${1}"
}

st_delete() {
    curl -sf -X DELETE -H "X-API-Key: $APIKEY" "${ST_URL}${1}"
}

check_deps() {
    local missing=()
    for cmd in "$@"; do
        if ! command -v "$cmd" >/dev/null 2>&1; then
            missing+=("$cmd")
        fi
    done
    if [ ${#missing[@]} -gt 0 ]; then
        die "Missing required dependencies: ${missing[*]}"
    fi
}

show_own_device_id() {
    header "This Device's ID"
    local id
    id=$(st_get /rest/system/status | python3 -c 'import sys,json; print(json.load(sys.stdin)["myID"])')
    echo -e "  ${GREEN}${id}${NC}"
    echo ""
}

show_pending_devices() {
    header "Pending Devices"
    local pending
    pending=$(st_get /rest/cluster/pending/devices)
    local count
    count=$(echo "$pending" | python3 -c 'import sys,json; d=json.load(sys.stdin); print(len(d))')
    if [ "$count" -eq 0 ]; then
        warn "No pending devices."
        return
    fi
    echo "$pending" | python3 -c '
import sys, json
devices = json.load(sys.stdin)
for device_id, info in devices.items():
    name = info.get("name", "(unknown)")
    print(f"  Name: {name}")
    print(f"  ID:   {device_id}")
    print()
'
    read -rp "Add a pending device? [y/N]: " ADD_PENDING
    if [[ "${ADD_PENDING,,}" == "y" ]]; then
        add_device_by_pending "$pending"
    fi
}

add_device_by_pending() {
    local pending="$1"
    local ids
    ids=$(echo "$pending" | python3 -c 'import sys,json; [print(k) for k in json.load(sys.stdin)]')
    local id_list=()
    while IFS= read -r line; do
        id_list+=("$line")
    done <<< "$ids"

    if [ ${#id_list[@]} -eq 1 ]; then
        DEVICE_ID="${id_list[0]}"
        local pending_name
        pending_name=$(echo "$pending" | python3 -c "import sys,json; d=json.load(sys.stdin); print(d['${DEVICE_ID}'].get('name',''))")
    else
        echo "Pending devices:"
        local i=1
        for id in "${id_list[@]}"; do
            local name
            name=$(echo "$pending" | python3 -c "import sys,json; d=json.load(sys.stdin); print(d['${id}'].get('name','(unknown)'))")
            echo "  $i) $name — $id"
            i=$((i+1))
        done
        read -rp "Choose [1-${#id_list[@]}]: " CHOICE
        [[ "$CHOICE" =~ ^[0-9]+$ ]] && [ "$CHOICE" -ge 1 ] && [ "$CHOICE" -le "${#id_list[@]}" ] || die "Invalid choice."
        DEVICE_ID="${id_list[$((CHOICE-1))]}"
        pending_name=$(echo "$pending" | python3 -c "import sys,json; d=json.load(sys.stdin); print(d['${DEVICE_ID}'].get('name',''))")
    fi

    read -rp "Device name [${pending_name:-new-device}]: " DEVICE_NAME
    DEVICE_NAME="${DEVICE_NAME:-${pending_name:-new-device}}"
    _do_add_device "$DEVICE_ID" "$DEVICE_NAME"
}

list_devices() {
    header "Devices"
    st_get /rest/config/devices | python3 -c '
import sys, json
devices = json.load(sys.stdin)
if not devices:
    print("  No devices configured.")
else:
    for d in devices:
        print("  Name: " + d["name"])
        print("  ID:   " + d["deviceID"])
        print()
'
}

add_device() {
    header "Add Device"
    read -rp "Device ID: " DEVICE_ID
    [ -n "$DEVICE_ID" ] || die "Device ID cannot be empty."
    read -rp "Device name: " DEVICE_NAME
    [ -n "$DEVICE_NAME" ] || die "Device name cannot be empty."
    _do_add_device "$DEVICE_ID" "$DEVICE_NAME"
}

_do_add_device() {
    local device_id="$1"
    local device_name="$2"
    local existing
    existing=$(st_get /rest/config/devices)
    local already
    already=$(echo "$existing" | python3 -c "import sys,json; devs=json.load(sys.stdin); print(any(d['deviceID']=='${device_id}' for d in devs))")
    if [ "$already" = "True" ]; then
        warn "Device '${device_name}' is already configured."
        return
    fi
    local payload
    payload=$(python3 -c "import json; print(json.dumps({'deviceID': '${device_id}', 'name': '${device_name}', 'addresses': ['dynamic'], 'autoAcceptFolders': False}))")
    st_post /rest/config/devices "$payload" >/dev/null
    info "Device '${device_name}' added."
}

remove_device() {
    header "Remove Device"
    local devices
    devices=$(st_get /rest/config/devices)
    local count
    count=$(echo "$devices" | python3 -c 'import sys,json; print(len(json.load(sys.stdin)))')
    [ "$count" -gt 0 ] || { warn "No devices configured."; return; }

    echo "$devices" | python3 -c '
import sys, json
for i, d in enumerate(json.load(sys.stdin), 1):
    print("  " + str(i) + ") " + d["name"] + " — " + d["deviceID"])
'
    echo ""
    read -rp "Choose device to remove [1-${count}]: " CHOICE
    [[ "$CHOICE" =~ ^[0-9]+$ ]] && [ "$CHOICE" -ge 1 ] && [ "$CHOICE" -le "$count" ] || die "Invalid choice."

    local device_id device_name
    device_id=$(echo "$devices" | python3 -c "import sys,json; d=json.load(sys.stdin); print(d[$((CHOICE-1))]['deviceID'])")
    device_name=$(echo "$devices" | python3 -c "import sys,json; d=json.load(sys.stdin); print(d[$((CHOICE-1))]['name'])")

    local folders
    folders=$(st_get /rest/config/folders)
    local shared_folders
    shared_folders=$(echo "$folders" | python3 -c "
import sys, json
folders = json.load(sys.stdin)
shared = [f['label'] or f['id'] for f in folders if any(dev['deviceID']=='${device_id}' for dev in f.get('devices',[]))]
print('\n'.join(shared))
")
    if [ -n "$shared_folders" ]; then
        warn "Device '${device_name}' is still sharing these folders:"
        echo "$shared_folders" | sed 's/^/    /'
        warn "Removing the device will unshare these folders from it."
    fi

    read -rp "Remove '${device_name}'? [y/N]: " CONFIRM
    [[ "${CONFIRM,,}" == "y" ]] || { info "Aborted."; return; }

    st_delete "/rest/config/devices/${device_id}" >/dev/null
    info "Device '${device_name}' removed."
}

list_folders() {
    header "Folders"
    st_get /rest/config/folders | python3 -c '
import sys, json
folders = json.load(sys.stdin)
if not folders:
    print("  No folders configured.")
else:
    for f in folders:
        label = f["label"] or f["id"]
        shared = len(f.get("devices", []))
        print("  Label:  " + label)
        print("  ID:     " + f["id"])
        print("  Path:   " + f["path"])
        print("  Shared: " + str(shared) + " device(s)")
        print()
'
}

add_folder() {
    header "Add Folder"
    read -rp "Folder path on this device (e.g. /var/syncthing/docs): " FOLDER_PATH
    [ -n "$FOLDER_PATH" ] || die "Path cannot be empty."
    read -rp "Folder label (human-readable name): " FOLDER_LABEL
    [ -n "$FOLDER_LABEL" ] || die "Label cannot be empty."
    read -rp "Folder ID (leave blank to use label): " FOLDER_ID
    FOLDER_ID="${FOLDER_ID:-$FOLDER_LABEL}"

    local existing
    existing=$(st_get /rest/config/folders)
    local already
    already=$(echo "$existing" | python3 -c "import sys,json; folders=json.load(sys.stdin); print(any(f['id']=='${FOLDER_ID}' for f in folders))")
    [ "$already" = "False" ] || die "Folder ID '${FOLDER_ID}' already exists."

    local payload
    payload=$(python3 -c "import json; print(json.dumps({'id': '${FOLDER_ID}', 'label': '${FOLDER_LABEL}', 'path': '${FOLDER_PATH}', 'type': 'sendreceive', 'devices': []}))")
    st_post /rest/config/folders "$payload" >/dev/null
    info "Folder '${FOLDER_LABEL}' added."
}

remove_folder() {
    header "Remove Folder"
    local folders
    folders=$(st_get /rest/config/folders)
    local count
    count=$(echo "$folders" | python3 -c 'import sys,json; print(len(json.load(sys.stdin)))')
    [ "$count" -gt 0 ] || { warn "No folders configured."; return; }

    echo "$folders" | python3 -c '
import sys, json
for i, f in enumerate(json.load(sys.stdin), 1):
    label = f["label"] or f["id"]
    print("  " + str(i) + ") " + label + " (" + f["path"] + ")")
'
    echo ""
    read -rp "Choose folder to remove [1-${count}]: " CHOICE
    [[ "$CHOICE" =~ ^[0-9]+$ ]] && [ "$CHOICE" -ge 1 ] && [ "$CHOICE" -le "$count" ] || die "Invalid choice."

    local folder_id folder_label
    folder_id=$(echo "$folders" | python3 -c "import sys,json; f=json.load(sys.stdin)[$((CHOICE-1))]; print(f['id'])")
    folder_label=$(echo "$folders" | python3 -c "import sys,json; f=json.load(sys.stdin)[$((CHOICE-1))]; print(f['label'] or f['id'])")

    read -rp "Remove folder '${folder_label}'? [y/N]: " CONFIRM
    [[ "${CONFIRM,,}" == "y" ]] || { info "Aborted."; return; }

    st_delete "/rest/config/folders/${folder_id}" >/dev/null
    info "Folder '${folder_label}' removed."
}

share_folder() {
    header "Share Folder with Device"
    local folders devices
    folders=$(st_get /rest/config/folders)
    devices=$(st_get /rest/config/devices)

    local f_count d_count
    f_count=$(echo "$folders" | python3 -c 'import sys,json; print(len(json.load(sys.stdin)))')
    d_count=$(echo "$devices" | python3 -c 'import sys,json; print(len(json.load(sys.stdin)))')
    [ "$f_count" -gt 0 ] || { warn "No folders configured."; return; }
    [ "$d_count" -gt 0 ] || { warn "No devices configured."; return; }

    echo "Folders:"
    echo "$folders" | python3 -c '
import sys, json
for i, f in enumerate(json.load(sys.stdin), 1):
    label = f["label"] or f["id"]
    print("  " + str(i) + ") " + label)
'
    echo ""
    read -rp "Choose folder [1-${f_count}]: " F_CHOICE
    [[ "$F_CHOICE" =~ ^[0-9]+$ ]] && [ "$F_CHOICE" -ge 1 ] && [ "$F_CHOICE" -le "$f_count" ] || die "Invalid choice."

    echo ""
    echo "Devices:"
    echo "$devices" | python3 -c '
import sys, json
for i, d in enumerate(json.load(sys.stdin), 1):
    print("  " + str(i) + ") " + d["name"])
'
    echo ""
    read -rp "Choose device [1-${d_count}]: " D_CHOICE
    [[ "$D_CHOICE" =~ ^[0-9]+$ ]] && [ "$D_CHOICE" -ge 1 ] && [ "$D_CHOICE" -le "$d_count" ] || die "Invalid choice."

    local folder_id device_id device_name folder_label
    folder_id=$(echo "$folders" | python3 -c "import sys,json; f=json.load(sys.stdin)[$((F_CHOICE-1))]; print(f['id'])")
    folder_label=$(echo "$folders" | python3 -c "import sys,json; f=json.load(sys.stdin)[$((F_CHOICE-1))]; print(f['label'] or f['id'])")
    device_id=$(echo "$devices" | python3 -c "import sys,json; d=json.load(sys.stdin)[$((D_CHOICE-1))]; print(d['deviceID'])")
    device_name=$(echo "$devices" | python3 -c "import sys,json; d=json.load(sys.stdin)[$((D_CHOICE-1))]; print(d['name'])")

    local folder_config already
    folder_config=$(st_get "/rest/config/folders/${folder_id}")
    already=$(echo "$folder_config" | python3 -c "import sys,json; f=json.load(sys.stdin); print(any(d['deviceID']=='${device_id}' for d in f.get('devices',[])))")
    if [ "$already" = "True" ]; then
        warn "Folder '${folder_label}' is already shared with '${device_name}'."
        return
    fi

    local updated
    updated=$(echo "$folder_config" | python3 -c "
import sys, json
f = json.load(sys.stdin)
f['devices'].append({'deviceID': '${device_id}', 'introducedBy': ''})
print(json.dumps(f))
")
    st_put "/rest/config/folders/${folder_id}" "$updated" >/dev/null
    info "Folder '${folder_label}' shared with '${device_name}'."
}

unshare_folder() {
    header "Unshare Folder from Device"
    local folders devices
    folders=$(st_get /rest/config/folders)
    devices=$(st_get /rest/config/devices)

    local f_count
    f_count=$(echo "$folders" | python3 -c 'import sys,json; print(len(json.load(sys.stdin)))')
    [ "$f_count" -gt 0 ] || { warn "No folders configured."; return; }

    echo "Folders:"
    echo "$folders" | python3 -c '
import sys, json
for i, f in enumerate(json.load(sys.stdin), 1):
    label = f["label"] or f["id"]
    shared = len(f.get("devices", []))
    print("  " + str(i) + ") " + label + " (" + str(shared) + " device(s))")
'
    echo ""
    read -rp "Choose folder [1-${f_count}]: " F_CHOICE
    [[ "$F_CHOICE" =~ ^[0-9]+$ ]] && [ "$F_CHOICE" -ge 1 ] && [ "$F_CHOICE" -le "$f_count" ] || die "Invalid choice."

    local folder_id folder_label folder_config
    folder_id=$(echo "$folders" | python3 -c "import sys,json; f=json.load(sys.stdin)[$((F_CHOICE-1))]; print(f['id'])")
    folder_label=$(echo "$folders" | python3 -c "import sys,json; f=json.load(sys.stdin)[$((F_CHOICE-1))]; print(f['label'] or f['id'])")
    folder_config=$(st_get "/rest/config/folders/${folder_id}")

    local shared_count
    shared_count=$(echo "$folder_config" | python3 -c 'import sys,json; print(len(json.load(sys.stdin).get("devices",[])))')
    [ "$shared_count" -gt 0 ] || { warn "Folder '${folder_label}' is not shared with any devices."; return; }

    local shared_ids
    shared_ids=$(echo "$folder_config" | python3 -c "import sys,json; [print(d['deviceID']) for d in json.load(sys.stdin).get('devices',[])]")

    echo ""
    echo "Shared with:"
    local i=1
    while IFS= read -r did; do
        local dname
        dname=$(echo "$devices" | python3 -c "import sys,json; devs=json.load(sys.stdin); match=[d['name'] for d in devs if d['deviceID']=='${did}']; print(match[0] if match else '${did}')")
        echo "  $i) $dname — $did"
        i=$((i+1))
    done <<< "$shared_ids"
    local shared_count_actual=$((i-1))

    echo ""
    read -rp "Choose device to unshare [1-${shared_count_actual}]: " D_CHOICE
    [[ "$D_CHOICE" =~ ^[0-9]+$ ]] && [ "$D_CHOICE" -ge 1 ] && [ "$D_CHOICE" -le "$shared_count_actual" ] || die "Invalid choice."

    local target_id
    target_id=$(echo "$shared_ids" | sed -n "${D_CHOICE}p")
    local target_name
    target_name=$(echo "$devices" | python3 -c "import sys,json; devs=json.load(sys.stdin); match=[d['name'] for d in devs if d['deviceID']=='${target_id}']; print(match[0] if match else '${target_id}')")

    read -rp "Unshare '${folder_label}' from '${target_name}'? [y/N]: " CONFIRM
    [[ "${CONFIRM,,}" == "y" ]] || { info "Aborted."; return; }

    local updated
    updated=$(echo "$folder_config" | python3 -c "
import sys, json
f = json.load(sys.stdin)
f['devices'] = [d for d in f['devices'] if d['deviceID'] != '${target_id}']
print(json.dumps(f))
")
    st_put "/rest/config/folders/${folder_id}" "$updated" >/dev/null
    info "Folder '${folder_label}' unshared from '${target_name}'."
}

check_deps curl docker python3

get_apikey

while true; do
    header "Syncthing Manager"
    echo "  0) Show This Device's ID"
    echo "  1) Pending Devices"
    echo "  2) List Devices"
    echo "  3) Add Device"
    echo "  4) Remove Device"
    echo "  5) List Folders"
    echo "  6) Add Folder"
    echo "  7) Remove Folder"
    echo "  8) Share Folder with Device"
    echo "  9) Unshare Folder from Device"
    echo "  q) Quit"
    echo ""
    read -rp "Choose: " OPT
    echo ""
    case "$OPT" in
        0) show_own_device_id ;;
        1) show_pending_devices ;;
        2) list_devices ;;
        3) add_device ;;
        4) remove_device ;;
        5) list_folders ;;
        6) add_folder ;;
        7) remove_folder ;;
        8) share_folder ;;
        9) unshare_folder ;;
        q|Q) echo "Bye."; exit 0 ;;
        *) warn "Invalid choice." ;;
    esac
done