#!/usr/bin/env python3
"""
Flask dashboard for CM4 eMMC provisioning.
Monitors deployment status, shows device connection steps, backup/restore.
Supports USB boot mode (ask Backup/Deploy) and network-booted devices (register, then Backup/Deploy).
"""

import json
import os
import re
import shutil
import subprocess
import tempfile
import threading
import time
import urllib.request
from pathlib import Path

from flask import Flask, render_template, jsonify, request, send_file, Response

app = Flask(__name__)


@app.after_request
def no_cache(response):
    """Prevent browser from caching the dashboard so deploys are visible immediately."""
    if request.path == "/" or request.path.startswith("/api/"):
        response.headers["Cache-Control"] = "no-store, no-cache, must-revalidate, max-age=0"
        response.headers["Pragma"] = "no-cache"
    return response


BASE_DIR = Path(os.environ.get("CM4_PROVISIONING_DIR", "/var/lib/cm4-provisioning"))
STATUS_FILE = os.environ.get("CM4_STATUS_FILE", str(BASE_DIR / "status.json"))
LOG_FILE = os.environ.get("CM4_LOG_FILE", str(BASE_DIR / "flash.log"))
ACTION_REQUEST_FILE = os.environ.get("CM4_ACTION_REQUEST_FILE", str(BASE_DIR / "action_request"))
DEVICE_SOURCE_FILE = os.environ.get("CM4_DEVICE_SOURCE_FILE", str(BASE_DIR / "device_source"))
BACKUPS_DIR = Path(os.environ.get("CM4_BACKUPS_DIR", str(BASE_DIR / "backups")))
GOLDEN_IMAGE = Path(os.environ.get("CM4_GOLDEN_IMAGE", str(BASE_DIR / "golden.img")))
NETWORK_DEVICES_FILE = Path(os.environ.get("CM4_NETWORK_DEVICES_FILE", str(BASE_DIR / "network_devices.json")))
BUILD_STATUS_FILE = Path(os.environ.get("CM4_BUILD_STATUS_FILE", str(BASE_DIR / "build_cloudinit_status.json")))

# Default cloud-init user-data for Raspberry Pi OS (NoCloud on boot partition)
DEFAULT_USER_DATA = """#cloud-config
package_update: true
package_upgrade: false
packages:
  - curl

runcmd:
  - curl -fsSL "http://YOUR_FILE_SERVER/provisioning/bootstrap.sh" -o /tmp/bootstrap.sh
  - chmod +x /tmp/bootstrap.sh
  - /tmp/bootstrap.sh
"""

DEFAULT_META_DATA = """instance-id: raspios-cloudinit-001
local-hostname: reterminal
"""

DEFAULT_NETWORK_CONFIG = """version: 2
ethernets:
  eth0:
    dhcp4: true
"""

DEFAULT_STATUS = {
    "phase": "idle",
    "message": "Waiting for reTerminal in boot mode or network.",
    "progress": None,
    "updated": None,
}


def read_status():
    try:
        with open(STATUS_FILE, "r") as f:
            data = json.load(f)
            out = {**DEFAULT_STATUS, **data}
            if out.get("phase") == "waiting_choice":
                try:
                    with open(DEVICE_SOURCE_FILE, "r") as sf:
                        out["device_source"] = (sf.read() or "").strip() or "usb"
                except (FileNotFoundError, OSError):
                    out["device_source"] = "usb"
            return out
    except (FileNotFoundError, json.JSONDecodeError):
        return DEFAULT_STATUS


def read_log_tail(lines=50):
    try:
        with open(LOG_FILE, "r") as f:
            all_lines = f.readlines()
            return "".join(all_lines[-lines:]).strip() if all_lines else ""
    except (FileNotFoundError, PermissionError):
        return ""


def _load_network_devices():
    try:
        if NETWORK_DEVICES_FILE.is_file():
            with open(NETWORK_DEVICES_FILE, "r") as f:
                return json.load(f)
    except (json.JSONDecodeError, OSError):
        pass
    return {"devices": []}


def _save_network_devices(data):
    try:
        os.makedirs(NETWORK_DEVICES_FILE.parent, exist_ok=True)
        with open(NETWORK_DEVICES_FILE, "w") as f:
            json.dump(data, f, indent=2)
        return True
    except (PermissionError, OSError):
        return False


BACKUPS_META_FILE = BACKUPS_DIR / "backups_meta.json"


def _load_backups_meta():
    try:
        if BACKUPS_META_FILE.is_file():
            with open(BACKUPS_META_FILE, "r") as f:
                return json.load(f)
    except (json.JSONDecodeError, OSError):
        pass
    return {}


def _save_backups_meta(data):
    try:
        BACKUPS_DIR.mkdir(parents=True, exist_ok=True)
        with open(BACKUPS_META_FILE, "w") as f:
            json.dump(data, f, indent=2)
        return True
    except (PermissionError, OSError):
        return False


def _safe_backup_name(name):
    """Reject path traversal and ensure it's a backup filename we manage."""
    if not name or ".." in name or "/" in name or "\\" in name:
        return False
    if not name.endswith((".img", ".img.gz", ".img.xz")):
        return False
    return True


def list_backups():
    if not BACKUPS_DIR.is_dir():
        return []
    meta = _load_backups_meta()
    out = []
    for p in sorted(BACKUPS_DIR.iterdir(), key=lambda x: x.stat().st_mtime, reverse=True):
        if p.is_file() and p.name != "backups_meta.json" and p.name.endswith((".img", ".img.gz", ".img.xz")):
            try:
                st = p.stat()
                m = meta.get(p.name, {})
                out.append({
                    "name": p.name,
                    "display_name": m.get("name") or p.name,
                    "description": m.get("description") or "",
                    "size": st.st_size,
                    "mtime": st.st_mtime,
                })
            except OSError:
                pass
    return out


@app.route("/")
def index():
    return render_template("index.html")


@app.route("/api/status")
def api_status():
    return jsonify(read_status())


@app.route("/api/status-clear", methods=["POST"])
def api_status_clear():
    """Reset status to idle (e.g. to dismiss a 'Golden image not found' error so you can try again)."""
    try:
        with open(STATUS_FILE, "w") as f:
            json.dump({
                "phase": "idle",
                "message": DEFAULT_STATUS["message"],
                "progress": None,
                "updated": None,
            }, f)
        return jsonify({"ok": True})
    except (PermissionError, OSError):
        return jsonify({"ok": False, "error": "Could not write status"}), 500


@app.route("/api/log")
def api_log():
    return jsonify({"log": read_log_tail()})


@app.route("/api/pending-devices")
def api_pending_devices():
    """Returns USB (if waiting_choice) and registered network devices so the UI can show Backup/Deploy."""
    st = read_status()
    usb = None
    if st.get("phase") == "waiting_choice":
        usb = {"source": "usb", "message": st.get("message", "Device connected (USB). Choose action.")}
    data = _load_network_devices()
    network = [d for d in data.get("devices", []) if d.get("action") in (None, "wait")]
    return jsonify({"usb": usb, "network": network})


@app.route("/api/device-action", methods=["POST"])
def api_device_action():
    """User chose Backup or Deploy for a device. source=usb | network; for network pass mac=."""
    body = request.get_json(force=True, silent=True) or {}
    source = (body.get("source") or "").strip().lower()
    action = (body.get("action") or "").strip().lower()
    if action not in ("backup", "deploy"):
        return jsonify({"ok": False, "error": "action must be 'backup' or 'deploy'"}), 400
    if source == "usb":
        try:
            os.makedirs(os.path.dirname(ACTION_REQUEST_FILE) or ".", exist_ok=True)
            # If user requested "shrink after backup", create flag so host runs PiShrink after dd
            if action == "backup" and body.get("shrink"):
                try:
                    (BASE_DIR / "shrink_next_backup").write_text("1")
                except (PermissionError, OSError):
                    pass  # host may still have SHRINK_BACKUP=1
            with open(ACTION_REQUEST_FILE, "w") as f:
                f.write(action)
            return jsonify({"ok": True})
        except (PermissionError, OSError):
            return jsonify({"ok": False, "error": "Could not write action file"}), 500
    if source == "network":
        mac = (body.get("mac") or "").strip()
        if not mac:
            return jsonify({"ok": False, "error": "mac required for network device"}), 400
        data = _load_network_devices()
        for d in data.get("devices", []):
            if (d.get("mac") or "").lower() == mac.lower():
                d["action"] = action
                d["action_at"] = time.time()
                _save_network_devices(data)
                return jsonify({"ok": True})
        return jsonify({"ok": False, "error": "Device not found"}), 404
    return jsonify({"ok": False, "error": "source must be 'usb' or 'network'"}), 400


@app.route("/api/register-device", methods=["POST"])
def api_register_device():
    """Called by a network-booted device to register (mac, ip)."""
    body = request.get_json(force=True, silent=True) or request.form
    mac = (body.get("mac") or "").strip()
    ip = (body.get("ip") or request.remote_addr or "").strip()
    if not mac:
        return jsonify({"ok": False, "error": "mac required"}), 400
    data = _load_network_devices()
    devices = data.get("devices", [])
    for d in devices:
        if (d.get("mac") or "").lower() == mac.lower():
            d["ip"] = ip
            d["registered_at"] = time.time()
            d["action"] = d.get("action") or "wait"
            _save_network_devices(data)
            return jsonify({"ok": True, "message": "registered"})
    devices.append({"mac": mac, "ip": ip, "registered_at": time.time(), "action": "wait"})
    data["devices"] = devices
    _save_network_devices(data)
    return jsonify({"ok": True, "message": "registered"})


@app.route("/api/device-action-poll")
def api_device_action_poll():
    """Network device polls this to get its assigned action (deploy/backup) and URL."""
    mac = (request.args.get("mac") or "").strip()
    if not mac:
        return jsonify({"action": "wait"}), 200
    data = _load_network_devices()
    base = request.host_url.rstrip("/")
    for d in data.get("devices", []):
        if (d.get("mac") or "").lower() == mac.lower():
            action = d.get("action") or "wait"
            if action == "deploy":
                return jsonify({"action": "deploy", "url": f"{base}/api/golden-image"})
            if action == "backup":
                return jsonify({"action": "backup", "upload_url": f"{base}/api/backup-upload?mac={mac}"})
            return jsonify({"action": "wait"})
    return jsonify({"action": "wait"})


@app.route("/api/golden-image")
def api_golden_image():
    """Stream the golden image for network deploy (device pulls and writes to eMMC)."""
    if not GOLDEN_IMAGE.is_file():
        return jsonify({"error": "Golden image not found"}), 404
    return send_file(
        GOLDEN_IMAGE,
        mimetype="application/octet-stream",
        as_attachment=True,
        download_name="golden.img",
    )


@app.route("/api/backup-upload", methods=["POST"])
def api_backup_upload():
    """Network device uploads its eMMC backup (raw body)."""
    mac = (request.args.get("mac") or "").strip().replace(":", "-")[:20]
    if not mac:
        return jsonify({"error": "mac query param required"}), 400
    BACKUPS_DIR.mkdir(parents=True, exist_ok=True)
    name = f"backup-net-{mac}-{int(time.time())}.img"
    path = BACKUPS_DIR / name
    try:
        with open(path, "wb") as f:
            while True:
                chunk = request.stream.read(1024 * 1024)
                if not chunk:
                    break
                f.write(chunk)
        return jsonify({"ok": True, "file": name})
    except (OSError, IOError) as e:
        if path.exists():
            path.unlink(missing_ok=True)
        return jsonify({"error": str(e)}), 500


@app.route("/api/backups")
def api_backups():
    return jsonify({"backups": list_backups()})


@app.route("/api/backups/<path:name>/set-as-golden", methods=["POST"])
def api_backup_set_as_golden(name):
    """Copy this backup to golden.img so it becomes the image used for Deploy."""
    if not _safe_backup_name(name):
        return jsonify({"ok": False, "error": "invalid backup name"}), 400
    path = BACKUPS_DIR / name
    if not path.is_file():
        return jsonify({"ok": False, "error": "backup not found"}), 404
    try:
        BACKUPS_DIR.mkdir(parents=True, exist_ok=True)
        shutil.copy2(path, GOLDEN_IMAGE)
        return jsonify({"ok": True, "message": f"Golden image set from {name}"})
    except (OSError, IOError) as e:
        return jsonify({"ok": False, "error": str(e)}), 500


@app.route("/api/backups/<path:name>/shrink", methods=["POST"])
def api_backup_shrink(name):
    """Run PiShrink on a raw .img backup (shrinks in place). Requires PiShrink in LXC/host."""
    if not _safe_backup_name(name):
        return jsonify({"ok": False, "error": "invalid backup name"}), 400
    if not name.endswith(".img") or name.endswith(".img.gz") or name.endswith(".img.xz"):
        return jsonify({"ok": False, "error": "only raw .img files can be shrunk (not .img.gz / .img.xz)"}), 400
    path = BACKUPS_DIR / name
    if not path.is_file():
        return jsonify({"ok": False, "error": "backup not found"}), 404
    pishrink = shutil.which("pishrink.sh") or "/usr/local/bin/pishrink.sh"
    if not pishrink or not os.path.isfile(pishrink):
        return jsonify({"ok": False, "error": "PiShrink not installed. Install on the host/LXC (e.g. scripts/install-pishrink-on-host.sh)"}), 503
    try:
        proc = subprocess.run(
            [pishrink, "-n", name],
            cwd=str(BACKUPS_DIR),
            capture_output=True,
            text=True,
            timeout=3600,
        )
        if proc.returncode != 0:
            return jsonify({
                "ok": False,
                "error": "PiShrink failed",
                "detail": (proc.stderr or proc.stdout or "").strip() or f"exit code {proc.returncode}",
            }), 500
        return jsonify({"ok": True, "message": f"Shrunk {name}"})
    except subprocess.TimeoutExpired:
        return jsonify({"ok": False, "error": "PiShrink timed out"}), 504
    except OSError as e:
        return jsonify({"ok": False, "error": str(e)}), 500


@app.route("/api/backups/<path:name>/compress", methods=["POST"])
def api_backup_compress(name):
    """Run PiShrink with compression (shrink + gz or xz) on a raw .img backup. Produces .img.gz or .img.xz."""
    if not _safe_backup_name(name):
        return jsonify({"ok": False, "error": "invalid backup name"}), 400
    if not name.endswith(".img") or name.endswith(".img.gz") or name.endswith(".img.xz"):
        return jsonify({"ok": False, "error": "only raw .img files can be compressed (not .img.gz / .img.xz)"}), 400
    path = BACKUPS_DIR / name
    if not path.is_file():
        return jsonify({"ok": False, "error": "backup not found"}), 404
    body = request.get_json(force=True, silent=True) or {}
    fmt = (body.get("format") or request.args.get("format") or "xz").strip().lower()
    if fmt not in ("gz", "gzip", "xz"):
        fmt = "xz"
    if fmt == "gzip":
        fmt = "gz"
    pishrink = shutil.which("pishrink.sh") or "/usr/local/bin/pishrink.sh"
    if not pishrink or not os.path.isfile(pishrink):
        return jsonify({"ok": False, "error": "PiShrink not installed"}), 503
    opts = ["-n", "-Z", "-a"] if fmt == "xz" else ["-n", "-z", "-a"]
    try:
        proc = subprocess.run(
            [pishrink] + opts + [name],
            cwd=str(BACKUPS_DIR),
            capture_output=True,
            text=True,
            timeout=3600,
        )
        if proc.returncode != 0:
            return jsonify({
                "ok": False,
                "error": "PiShrink failed",
                "detail": (proc.stderr or proc.stdout or "").strip() or f"exit code {proc.returncode}",
            }), 500
        ext = ".xz" if fmt == "xz" else ".gz"
        return jsonify({"ok": True, "message": f"Compressed to {name}{ext}"})
    except subprocess.TimeoutExpired:
        return jsonify({"ok": False, "error": "PiShrink timed out"}), 504
    except OSError as e:
        return jsonify({"ok": False, "error": str(e)}), 500


@app.route("/api/backups/<path:name>", methods=["PATCH"])
def api_backup_update(name):
    """Update backup metadata (display name, description) or rename the file."""
    if not _safe_backup_name(name):
        return jsonify({"ok": False, "error": "invalid backup name"}), 400
    path = BACKUPS_DIR / name
    if not path.is_file():
        return jsonify({"ok": False, "error": "backup not found"}), 404
    body = request.get_json(force=True, silent=True) or {}
    meta = _load_backups_meta()
    entry = meta.get(name, {})

    new_filename = (body.get("filename") or "").strip()
    if new_filename:
        if not _safe_backup_name(new_filename):
            return jsonify({"ok": False, "error": "invalid new filename"}), 400
        new_path = BACKUPS_DIR / new_filename
        if new_path.exists() and new_path != path:
            return jsonify({"ok": False, "error": "target filename already exists"}), 409
        try:
            path.rename(new_path)
        except OSError as e:
            return jsonify({"ok": False, "error": str(e)}), 500
        meta[new_filename] = {"name": entry.get("name") or name, "description": entry.get("description") or ""}
        if name in meta:
            del meta[name]
        name = new_filename
        path = BACKUPS_DIR / name
    else:
        if "name" in body:
            entry["name"] = (body.get("name") or "").strip() or path.name
        if "description" in body:
            entry["description"] = (body.get("description") or "").strip()
        meta[name] = entry

    if not _save_backups_meta(meta):
        return jsonify({"ok": False, "error": "could not save metadata"}), 500
    return jsonify({"ok": True, "name": name})


@app.route("/api/backups/<path:name>", methods=["GET"])
def api_backup_download(name):
    if not _safe_backup_name(name):
        return jsonify({"error": "invalid name"}), 400
    path = BACKUPS_DIR / name
    if not path.is_file():
        return jsonify({"error": "not found"}), 404
    return send_file(path, as_attachment=True, download_name=name)


def _build_status_read():
    try:
        if BUILD_STATUS_FILE.is_file():
            with open(BUILD_STATUS_FILE, "r") as f:
                return json.load(f)
    except (json.JSONDecodeError, OSError):
        pass
    return {"phase": "idle", "message": "", "output_name": None, "error": None}


def _build_status_write(phase, message, output_name=None, error=None):
    try:
        BUILD_STATUS_FILE.parent.mkdir(parents=True, exist_ok=True)
        with open(BUILD_STATUS_FILE, "w") as f:
            json.dump({
                "phase": phase,
                "message": message,
                "output_name": output_name,
                "error": error,
                "updated": time.time(),
            }, f, indent=2)
    except OSError:
        pass


def _raspios_latest_lite_url():
    """Resolve latest Raspberry Pi OS Lite (arm64) .img.xz URL from official index."""
    base = "https://downloads.raspberrypi.com/raspios_lite_arm64/images"
    try:
        with urllib.request.urlopen(base + "/", timeout=15) as r:
            html = r.read().decode("utf-8", errors="ignore")
        # Match raspios_lite_arm64-YYYY-MM-DD/
        folders = re.findall(r"raspios_lite_arm64-(\d{4}-\d{2}-\d{2})/", html)
        if not folders:
            return None
        latest = sorted(folders)[-1]
        folder_url = f"{base}/raspios_lite_arm64-{latest}/"
        with urllib.request.urlopen(folder_url, timeout=15) as r:
            folder_html = r.read().decode("utf-8", errors="ignore")
        # Match .img.xz link (skip .sha256, .torrent, etc.)
        m = re.search(r'href="([^"]+\.img\.xz)"', folder_html)
        if not m:
            return None
        return folder_url + m.group(1)
    except Exception:
        return None


def _build_cloudinit_worker(variant, user_data, meta_data, network_config):
    """Background: download Raspios, inject cloud-init, save to BACKUPS_DIR."""
    out_name = f"raspios-{variant}-cloudinit-{time.strftime('%Y%m%d-%H%M%S')}.img"
    out_path = BACKUPS_DIR / out_name
    mount_point = None
    loop_dev = None
    temp_dir = None
    img_path = None
    xz_path = None
    try:
        _build_status_write("resolving", "Resolving latest Raspberry Pi OS image URL…")
        url = _raspios_latest_lite_url()
        if not url:
            _build_status_write("error", "", output_name=None, error="Could not resolve latest Raspios Lite URL")
            return
        _build_status_write("downloading", f"Downloading {url.split('/')[-1]}… (this may take several minutes)")
        temp_dir = Path(tempfile.mkdtemp(prefix="cloudinit-build-", dir=str(BACKUPS_DIR)))
        xz_path = temp_dir / "image.img.xz"
        with urllib.request.urlopen(url, timeout=3600) as resp:
            total = int(resp.headers.get("Content-Length", 0)) or 0
            chunk_size = 1024 * 1024
            with open(xz_path, "wb") as f:
                done = 0
                while True:
                    chunk = resp.read(chunk_size)
                    if not chunk:
                        break
                    f.write(chunk)
                    done += len(chunk)
                    if total and done % (50 * 1024 * 1024) < chunk_size:
                        _build_status_write("downloading", f"Downloaded {done // (1024*1024)} MB…")
        _build_status_write("decompressing", "Decompressing image…")
        img_path = temp_dir / "image.img"
        subprocess.run(["xz", "-d", "-k", "-f", str(xz_path)], check=True, capture_output=True, timeout=1800, cwd=str(temp_dir))
        if not img_path.exists():
            _build_status_write("error", "", output_name=None, error="Decompress failed: image.img not found")
            return
        _build_status_write("injecting", "Mounting boot partition and injecting cloud-init…")
        loop_out = subprocess.run(["losetup", "-f", "--show", "-P", str(img_path)], capture_output=True, text=True, timeout=10)
        if loop_out.returncode != 0:
            _build_status_write("error", "", output_name=None, error="losetup failed (loop device may not be available in this container)")
            return
        loop_dev = loop_out.stdout.strip()
        # First partition is usually boot (FAT32)
        boot_part = f"{loop_dev}p1"
        if not Path(boot_part).exists():
            boot_part = f"{loop_dev}p2"
        if not Path(boot_part).exists():
            _build_status_write("error", "", output_name=None, error="Boot partition not found")
            return
        mount_point = temp_dir / "mnt"
        mount_point.mkdir(exist_ok=True)
        subprocess.run(["mount", boot_part, str(mount_point)], check=True, capture_output=True, timeout=10)
        try:
            (mount_point / "user-data").write_text(user_data or DEFAULT_USER_DATA)
            (mount_point / "meta-data").write_text(meta_data or DEFAULT_META_DATA)
            (mount_point / "network-config").write_text(network_config or DEFAULT_NETWORK_CONFIG)
        finally:
            subprocess.run(["umount", str(mount_point)], capture_output=True, timeout=10)
        subprocess.run(["losetup", "-d", loop_dev], capture_output=True, timeout=10)
        loop_dev = None
        _build_status_write("finalizing", "Copying image to backups…")
        shutil.copy2(str(img_path), str(out_path))
        _build_status_write("done", f"Built {out_name}", output_name=out_name)
    except subprocess.TimeoutExpired as e:
        _build_status_write("error", "", output_name=None, error=f"Timeout: {e}")
    except subprocess.CalledProcessError as e:
        _build_status_write("error", "", output_name=None, error=f"Command failed: {e.stderr or e}")
    except Exception as e:
        _build_status_write("error", "", output_name=None, error=str(e))
    finally:
        if loop_dev:
            try:
                subprocess.run(["losetup", "-d", loop_dev], capture_output=True, timeout=5)
            except Exception:
                pass
        if mount_point and mount_point.exists():
            try:
                subprocess.run(["umount", str(mount_point)], capture_output=True, timeout=5)
            except Exception:
                pass
        if temp_dir and temp_dir.exists():
            try:
                shutil.rmtree(temp_dir, ignore_errors=True)
            except Exception:
                pass


_build_lock = threading.Lock()
_build_thread = None


@app.route("/api/build-cloudinit-status")
def api_build_cloudinit_status():
    """Return current build status (phase, message, output_name, error)."""
    return jsonify(_build_status_read())


@app.route("/api/build-cloudinit", methods=["POST"])
def api_build_cloudinit():
    """Start building a cloud-init ready Raspberry Pi OS image (download latest Lite, inject NoCloud). Runs in background."""
    global _build_thread
    with _build_lock:
        st = _build_status_read()
        if st.get("phase") in ("downloading", "decompressing", "injecting", "finalizing", "resolving"):
            return jsonify({"ok": False, "error": "A build is already in progress"}), 409
        _build_thread = threading.Thread(
            target=_build_cloudinit_worker,
            kwargs={
                "variant": "lite",
                "user_data": (request.get_json(silent=True) or {}).get("user_data") or DEFAULT_USER_DATA,
                "meta_data": (request.get_json(silent=True) or {}).get("meta_data") or DEFAULT_META_DATA,
                "network_config": (request.get_json(silent=True) or {}).get("network_config") or DEFAULT_NETWORK_CONFIG,
            },
            daemon=True,
        )
        _build_thread.start()
    _build_status_write("resolving", "Starting…")
    return jsonify({"ok": True, "message": "Build started. Download and inject may take 15–30 min. Poll /api/build-cloudinit-status or refresh the page."}), 202


@app.route("/api/raspios-latest-url")
def api_raspios_latest_url():
    """Return the URL of the latest Raspberry Pi OS Lite arm64 image (for display only)."""
    url = _raspios_latest_lite_url()
    if not url:
        return jsonify({"ok": False, "url": None, "error": "Could not resolve latest image URL"}), 503
    return jsonify({"ok": True, "url": url, "filename": url.split("/")[-1]})


@app.route("/api/golden-info")
def api_golden_info():
    """Return whether golden image exists and its size/mtime for UI."""
    if not GOLDEN_IMAGE.is_file():
        return jsonify({"present": False})
    try:
        st = GOLDEN_IMAGE.stat()
        return jsonify({"present": True, "size": st.st_size, "mtime": st.st_mtime})
    except OSError:
        return jsonify({"present": False})


if __name__ == "__main__":
    app.run(host="0.0.0.0", port=5000, debug=False)