# ruff: noqa: E501 — inline HTML/CSS/JS payloads (_INDEX_HTML, _STYLE_CSS,
# _CADDYFILE, _FURTKA_STATUS_SH, etc.) round-trip verbatim to the installed
# system; wrapping them hurts readability and the rendered output is what
# matters.
import base64
import json
import os
import re
import subprocess
import sys
from datetime import UTC
from pathlib import Path

from drives import list_scored_devices
from flask import Flask, jsonify, redirect, render_template, request, url_for

app = Flask(__name__)


def _resolve_version() -> str:
    """Resolve the Furtka version to display in the wizard footer.

    On the live ISO `iso/build.sh` writes `/opt/furtka/VERSION` at build time
    from `pyproject.toml`; that's the authoritative source at runtime. For
    local dev runs (pytest, `flask run` outside the ISO) fall back to
    reading `pyproject.toml` directly, then to the literal "dev" so the
    footer never 500s if both files are missing.
    """
    iso_path = Path(__file__).resolve().parent / "VERSION"
    for candidate in (iso_path, Path(__file__).resolve().parent.parent / "pyproject.toml"):
        try:
            text = candidate.read_text(encoding="utf-8")
        except (FileNotFoundError, PermissionError, OSError):
            continue
        if candidate.name == "VERSION":
            value = text.strip()
            if value:
                return value
        else:
            match = re.search(r'^version\s*=\s*"([^"]+)"', text, re.MULTILINE)
            if match:
                return match.group(1)
    return "dev"


FURTKA_VERSION = _resolve_version()


@app.context_processor
def _inject_version():
    return {"furtka_version": FURTKA_VERSION}


LANGUAGES = {
    "en": {"locale": "en_US.UTF-8", "label": "English", "keyboard": "us"},
    "de": {"locale": "de_DE.UTF-8", "label": "Deutsch", "keyboard": "de"},
    "pl": {"locale": "pl_PL.UTF-8", "label": "Polski", "keyboard": "pl"},
}

STATE_DIR = Path(os.environ.get("FURTKA_STATE_DIR", "/tmp/furtka"))
INSTALL_LOG = STATE_DIR / "install.log"
CONFIG_PATH = STATE_DIR / "user_configuration.json"
CREDS_PATH = STATE_DIR / "user_credentials.json"

# Pre-populated with sane defaults so the form has something useful on first
# render. POSTs validate and overwrite.
settings = {
    "hostname": "furtka",
    "username": "",
    "password": "",
    "language": "en",
    "boot_drive": "",
}

HOSTNAME_RE = re.compile(r"^[a-z0-9]([a-z0-9-]{0,61}[a-z0-9])?$")
USERNAME_RE = re.compile(r"^[a-z_][a-z0-9_-]{0,31}$")

# Ordered phase markers for the install progress bar. Each tuple is
# (substring to search for in the archinstall log, progress percent when
# reached, user-facing label). Pick the furthest phase whose marker is
# present in the log. If archinstall changes its stdout wording the bar
# stalls on the last recognized phase — the install itself keeps going.
PROGRESS_PHASES = [
    ("Wiping partitions", 8, "Preparing your disk"),
    ("Creating partitions", 12, "Creating partitions"),
    ("Starting installation", 15, "Starting installation"),
    ("Waiting for", 18, "Syncing time and packages"),
    ("Installing packages: ['base'", 25, "Installing the base system (this takes a while)"),
    ("Adding bootloader", 65, "Setting up boot"),
    ("Installing packages: ['efibootmgr'", 70, "Setting up boot"),
    ("Installing packages: ['docker'", 80, "Installing your apps"),
    ("Enabling service", 90, "Turning on services"),
    ("Updating /mnt/etc/fstab", 95, "Almost done"),
    ("Installation completed without any errors", 100, "Done!"),
]

PROGRESS_ERROR_MARKERS = ("Traceback (most recent call last)", "archinstall: error:")


def parse_install_progress(log):
    percent = 2
    phase = "Starting up…"
    for marker, pct, label in PROGRESS_PHASES:
        if marker in log:
            percent = pct
            phase = label

    if percent >= 100:
        status = "done"
    elif any(m in log for m in PROGRESS_ERROR_MARKERS):
        status = "error"
        phase = "Installation failed — open Show details below"
    else:
        status = "running"

    return {"percent": percent, "phase": phase, "status": status}


def validate_step1(form):
    errors = []
    values = {
        "hostname": form.get("hostname", "").strip(),
        "username": form.get("username", "").strip(),
        "password": form.get("password", ""),
        "language": form.get("language", ""),
    }
    password2 = form.get("password2", "")

    if not HOSTNAME_RE.match(values["hostname"]):
        errors.append("Hostname must be lowercase letters, digits, hyphens (max 63 chars).")
    if not USERNAME_RE.match(values["username"]):
        errors.append("Username must start with a letter or underscore, lowercase only.")
    if len(values["password"]) < 8:
        errors.append("Password must be at least 8 characters.")
    if values["password"] != password2:
        errors.append("Passwords do not match.")
    if values["language"] not in LANGUAGES:
        errors.append("Pick a language.")
    return errors, values


def build_disk_config(boot_drive):
    # archinstall 4.x dropped the `use_entire_disk` shortcut — `default_layout`
    # now requires fully-specified partitions. We call suggest_single_disk_layout
    # with ext4 + no separate /home, which short-circuits its interactive prompts.
    import asyncio

    from archinstall.lib.disk.device_handler import device_handler
    from archinstall.lib.disk.disk_menu import suggest_single_disk_layout
    from archinstall.lib.models.device import (
        DiskLayoutConfiguration,
        DiskLayoutType,
        FilesystemType,
    )

    device_handler.load_devices()
    device = device_handler.get_device(Path(boot_drive))
    if device is None:
        raise RuntimeError(f"archinstall could not resolve device {boot_drive!r}")

    device_mod = asyncio.run(
        suggest_single_disk_layout(
            device,
            # archinstall renamed the enum members to ALL_CAPS at some point
            # between when we wrote this and the pinned Arch live ISO version.
            # The old name `Ext4` now raises AttributeError at install time.
            filesystem_type=FilesystemType.EXT4,
            separate_home=False,
        )
    )
    layout = DiskLayoutConfiguration(
        config_type=DiskLayoutType.Default,
        device_modifications=[device_mod],
    )
    return layout.json()


# ---------------------------------------------------------------------------
# Post-install bootstrap payload
#
# Written into the target system via archinstall's `custom_commands` so that
# after reboot the user lands in "Furtka": Caddy serves a branded landing
# page + live status tiles on :80, avahi advertises proksi.local, and the
# console shows a welcome banner pointing at the URL.
#
# Asset files (HTML, CSS, shell scripts, systemd units, Caddyfile) live in
# assets/ in the repo — at ISO build time they end up on the live ISO
# as part of the webinstaller's source tree AND inside the resource-manager
# payload tarball. The installer reads them from the live-ISO copy, base64-
# encodes them, and hands them to archinstall so the chroot recreates each
# file bit-for-bit. Updates (Phase 2) refresh the tarball, which carries the
# same assets to the target's /opt/furtka/ tree.
# ---------------------------------------------------------------------------

# Tarball built by iso/build.sh containing the furtka/ Python package + the
# bundled apps/ tree (plus assets/). The webinstaller reads it from the
# live ISO at request-time and base64-encodes it into a custom_command for
# archinstall.
RESOURCE_MANAGER_PAYLOAD = Path("/opt/furtka-resource-manager.tar.gz")


# Asset root. Two layouts we have to handle:
#   dev / tests  — webinstaller/app.py sits at repo_root/webinstaller/ and
#                  assets live at repo_root/assets/.
#   live ISO     — iso/build.sh copies webinstaller/ to /opt/furtka/ AND
#                  copies assets/ to /opt/assets/ right next to
#                  app.py, so the same "assets next to me" lookup works.
# Probe the sibling path first (ISO case), fall back to the repo layout.
def _resolve_assets_dir() -> Path:
    here = Path(__file__).resolve().parent
    sibling = here / "assets"
    if sibling.is_dir():
        return sibling
    repo_copy = here.parent / "assets"
    if repo_copy.is_dir():
        return repo_copy
    raise FileNotFoundError(
        f"furtka assets not found near {here} — looked in {sibling} and {repo_copy}"
    )


_ASSETS_DIR = _resolve_assets_dir()


def _read_asset(relpath: str) -> str:
    """Return the UTF-8 contents of an on-disk asset shipped under assets/.

    Raises FileNotFoundError if the asset is missing, which is loud by design:
    an install that tries to write an asset that isn't there is broken before
    the user ever boots the target, not after.
    """
    path = _ASSETS_DIR / relpath
    return path.read_text(encoding="utf-8")


_FURTKA_WRAPPER_SH = """\
#!/bin/sh
# Tiny launcher for the furtka resource-manager CLI. The Python source lives
# under /opt/furtka/current/furtka/ — /current is a symlink that gets
# flipped by self-updates (Phase 2), so this shim stays stable across
# upgrades while the underlying code tree is swapped atomically.
PYTHONPATH=/opt/furtka/current exec python3 -m furtka.cli "$@"
"""


def _write_file_cmd(path, content, mode=None):
    """Shell command that recreates `path` with `content` inside the chroot.

    Uses base64 so we don't have to worry about bash / JSON / archinstall
    quoting the payload through three layers of shell. `base64` is part of
    coreutils and always available in the target system.
    """
    b64 = base64.b64encode(content.encode()).decode()
    parent = path.rsplit("/", 1)[0]
    cmd = f"mkdir -p {parent} && printf %s {b64} | base64 -d > {path}"
    if mode is not None:
        cmd += f" && chmod {mode} {path}"
    return cmd


_FURTKA_UNITS = (
    "furtka-api.service",
    "furtka-reconcile.service",
    "furtka-status.service",
    "furtka-status.timer",
    "furtka-welcome.service",
    # Daily apps-catalog pull. Timer drives the service; the .service itself
    # is oneshot and also callable ad-hoc via `furtka catalog sync`.
    "furtka-catalog-sync.service",
    "furtka-catalog-sync.timer",
)


def _resource_manager_commands():
    """Commands to land /opt/furtka/versions/<ver>/ + symlink /opt/furtka/current
    + the `furtka` CLI shim + systemctl-link the unit files.

    Reads the payload tarball staged into the live ISO at build time. If the
    file isn't present (dev box without an ISO build), returns [] so the rest
    of the install still works — the resource manager just won't be installed,
    and nothing else on the system references furtka-* units.
    """
    if not RESOURCE_MANAGER_PAYLOAD.exists():
        print(
            f"warning: {RESOURCE_MANAGER_PAYLOAD} missing, "
            "resource manager will NOT be installed on target",
            file=sys.stderr,
        )
        return []
    payload_b64 = base64.b64encode(RESOURCE_MANAGER_PAYLOAD.read_bytes()).decode()
    # Extract to a staging directory first, then rename to versions/<ver>/.
    # That way the version-ID lookup is data-driven (reads VERSION from the
    # tarball) instead of hardcoded at install-time — keeps the installer
    # version-agnostic so a newer ISO doesn't need a webinstaller change to
    # ship a new Furtka version.
    extract_and_link = (
        "mkdir -p /opt/furtka/versions && "
        "staging=$(mktemp -d /opt/furtka/versions/staging-XXXXXX) && "
        f'printf %s {payload_b64} | base64 -d | tar -xzf - -C "$staging" && '
        'ver=$(cat "$staging/VERSION") && '
        # Guard against an empty VERSION file: without this, `mv "$staging"
        # "/opt/furtka/versions/"` would move the staging dir into versions/
        # as a subdir and the symlink target would be invalid.
        '[ -n "$ver" ] || { echo "empty VERSION in payload" >&2; exit 1; } && '
        'mv "$staging" "/opt/furtka/versions/$ver" && '
        # mktemp -d creates the staging dir with mode 700; that survives the
        # mv and leaves Caddy (which runs as the `caddy` user, not root)
        # unable to traverse /opt/furtka/current/ when it tries to serve
        # the landing page. Open up to 755 so file_server can read.
        'chmod 755 "/opt/furtka/versions/$ver" && '
        'ln -sfn "/opt/furtka/versions/$ver" /opt/furtka/current'
    )
    systemctl_link = "systemctl link " + " ".join(
        f"/opt/furtka/current/assets/systemd/{u}" for u in _FURTKA_UNITS
    )
    systemctl_enable = "systemctl enable " + " ".join(_FURTKA_UNITS)
    return [
        extract_and_link,
        _write_file_cmd("/usr/local/bin/furtka", _FURTKA_WRAPPER_SH, mode="755"),
        systemctl_link,
        systemctl_enable,
    ]


def _furtka_json_cmd(hostname):
    """Write /var/lib/furtka/furtka.json with install-time facts.

    Replaces the __HOSTNAME__ sed pass — the landing page reads this file
    at runtime and renders the hostname chip from it. install_date + version
    ride along so the settings page can display them without hitting the
    status timer's refresh cycle.

    Heredoc rather than base64 + sed — the previous version had two layers
    of quoting that archinstall's custom_commands shell-eval path parsed
    inconsistently, leaving this command as a silent no-op on some installs.
    The heredoc evaluates `$(date ...)` and `$(cat VERSION)` at chroot
    runtime and sidesteps the quoting hazard entirely. Hostname has already
    been validated by validate_step1.
    """
    return (
        "mkdir -p /var/lib/furtka && "
        "cat > /var/lib/furtka/furtka.json <<EOF\n"
        "{\n"
        f'  "hostname": "{hostname}",\n'
        '  "install_date": "$(date -Iseconds)",\n'
        '  "version": "$(cat /opt/furtka/current/VERSION 2>/dev/null || echo dev)"\n'
        "}\n"
        "EOF"
    )


def _users_json_cmd(username, password):
    """Write /var/lib/furtka/users.json with the admin account hashed.

    The core furtka-api reads this file on every login attempt; the
    auth.py module treats `admin.username` + `admin.hash` as the only
    credential. Hashing happens here in the webinstaller (werkzeug is a
    flask transitive dep so it's already installed in this environment)
    — the chroot doesn't need pip. Mode 0600 so nobody but root on the
    installed box can read the PBKDF2 hash.
    """
    from datetime import datetime

    from werkzeug.security import generate_password_hash

    users = {
        "admin": {
            "username": username,
            "hash": generate_password_hash(password),
            "created_at": datetime.now(UTC).isoformat(timespec="seconds"),
        }
    }
    return _write_file_cmd(
        "/var/lib/furtka/users.json",
        json.dumps(users, indent=2) + "\n",
        mode="600",
    )


def _post_install_commands(hostname, admin_username, admin_password):
    # nss-mdns: splice `mdns_minimal [NOTFOUND=return]` before `resolve` on
    # the hosts line so `*.local` works from the installed system too. Guarded
    # so a re-run (or a future Arch default that already ships mdns) is a
    # no-op instead of double-injecting.
    nss_sed = (
        "grep -q 'mdns_minimal' /etc/nsswitch.conf || "
        "sed -i '/^hosts:/ s/resolve/mdns_minimal [NOTFOUND=return] resolve/' "
        "/etc/nsswitch.conf"
    )
    return [
        # Import dir for the HTTP→HTTPS force-redirect snippet. The
        # /api/furtka/https/force endpoint writes/removes a .caddyfile here
        # to toggle the redirect. Must exist before Caddy starts — the
        # Caddyfile's glob `import /etc/caddy/furtka.d/*.caddyfile` tolerates
        # an empty dir but not a missing one on every Caddy version, so we
        # create it up front and stay on the safe side.
        "install -d -m 0755 -o root -g root /etc/caddy/furtka.d",
        # The Caddyfile lives at /etc/caddy/Caddyfile per Caddy's convention
        # (systemd unit points there). Content comes from the shipped asset,
        # which we copy in at install time so updates that change routing
        # need a new release to refresh it.
        #
        # __FURTKA_HOSTNAME__ is the placeholder the asset carries in place
        # of the real hostname — Caddy's `tls internal` needs a named site
        # block to issue a leaf cert, and the hostname isn't known until
        # the user fills in the form. Self-updates re-apply the same
        # substitution against /etc/hostname (see updater._refresh_caddyfile).
        _write_file_cmd(
            "/etc/caddy/Caddyfile",
            _read_asset("Caddyfile").replace("__FURTKA_HOSTNAME__", hostname),
        ),
        # Initial status.json so Caddy doesn't 404 before furtka-status fires.
        _write_file_cmd("/var/lib/furtka/status.json", _read_asset("www/status.json")),
        nss_sed,
        # Resource manager bootstrap: extract tarball → versions/<ver>/,
        # symlink current, install wrapper, systemctl-link unit files.
        *_resource_manager_commands(),
        # furtka.json depends on /opt/furtka/current/VERSION, so it has to
        # run after the resource-manager commands.
        _furtka_json_cmd(hostname),
        # Admin account for the Furtka web UI. Hashed here (werkzeug is
        # already in scope for the Flask webinstaller) and materialised
        # into /var/lib/furtka/users.json at mode 0600 on the target
        # partition — the installed core's auth.py picks it up on first
        # login.
        _users_json_cmd(admin_username, admin_password),
    ]


def _detect_bootloader():
    # systemd-boot is UEFI-only; on BIOS/legacy it trips HardwareIncompatibilityError
    # inside archinstall. /sys/firmware/efi exists iff we were booted via UEFI.
    return "Systemd-boot" if Path("/sys/firmware/efi").exists() else "Grub"


def build_archinstall_config(s):
    return {
        "archinstall-language": "English",
        "timezone": "Europe/Berlin",
        "ntp": True,
        "bootloader": _detect_bootloader(),
        "disk_config": build_disk_config(s["boot_drive"]),
        "hostname": s["hostname"],
        "kernels": ["linux"],
        "packages": [
            "docker",
            "docker-compose",
            # Editors for console/SSH recovery — `nano` is the beginner-friendly
            # one, `vim` stays because it's muscle-memory for the dev team.
            "nano",
            "vim",
            "git",
            "htop",
            "curl",
            # Remote access — archinstall 4.x's `ssh: True` flag is flaky about
            # actually pulling in openssh, so list it explicitly and enable sshd
            # via `services` below. Without this, the documented recovery path
            # (SSH in → edit .env) doesn't work.
            "openssh",
            # Base OS post-install (landing page + mDNS on installed system).
            "caddy",
            "avahi",
            "nss-mdns",
            # Resource manager runtime — pure-stdlib Python, no pip needed
            # because we expose the package via PYTHONPATH in /usr/local/bin/furtka.
            "python",
        ],
        "profile": {"type": "server"},
        "services": [
            "docker",
            # Base OS post-install services. Only packaged units go here —
            # archinstall runs `systemctl enable` on this list *before*
            # custom_commands, so our own furtka-welcome + furtka-status.timer
            # units (written in custom_commands) are enabled there instead.
            "caddy",
            "avahi-daemon",
            "sshd",
        ],
        # `gpasswd -a <user> docker` has to stay first — adds the user to
        # the docker group once the group exists (archinstall creates users
        # before pacstrapping extras). After that we drop the Furtka landing
        # page, status timer, and welcome banner into place.
        "custom_commands": [
            f"gpasswd -a {s['username']} docker",
            *_post_install_commands(s["hostname"], s["username"], s["password"]),
        ],
        "network_config": {"type": "iso"},
        "ssh": True,
        "audio_config": None,
        "locale_config": {
            "locale": LANGUAGES[s["language"]]["locale"],
            # Keyboard layout follows the chosen language so a German user
            # doesn't get a US layout at the TTY console (where things like
            # `/`, `-`, `=` land on surprising keys and make even `sudo vim`
            # painful). `en` falls through to "us" which is what we want.
            "keyboard_layout": LANGUAGES[s["language"]]["keyboard"],
        },
    }


def build_archinstall_creds(s):
    # archinstall 4.x expects `!root-password` and `!password` (plaintext
    # sentinels). Users with neither `!password` nor `enc_password` are
    # silently dropped by User.parse_arguments — hence login failures.
    return {
        "!root-password": s["password"],
        "users": [
            {
                "username": s["username"],
                "!password": s["password"],
                "sudo": True,
                "groups": [],
            }
        ],
    }


def write_install_files(s, state_dir):
    state_dir.mkdir(parents=True, exist_ok=True)
    config_path = state_dir / "user_configuration.json"
    creds_path = state_dir / "user_credentials.json"
    config_path.write_text(json.dumps(build_archinstall_config(s), indent=2))
    creds_path.write_text(json.dumps(build_archinstall_creds(s), indent=2))
    creds_path.chmod(0o600)
    return config_path, creds_path


def spawn_archinstall(config_path, creds_path, log_path):
    log_fh = open(log_path, "wb")
    return subprocess.Popen(
        [
            "archinstall",
            "--config",
            str(config_path),
            "--creds",
            str(creds_path),
            "--silent",
        ],
        stdout=log_fh,
        stderr=subprocess.STDOUT,
        start_new_session=True,
    )


@app.route("/")
def home():
    return redirect(url_for("install_step_1"))


@app.route("/install/step1", methods=["GET", "POST"])
def install_step_1():
    errors = []
    if request.method == "POST":
        errors, values = validate_step1(request.form)
        if not errors:
            settings.update(values)
            return redirect(url_for("install_step_2"))
        form_values = values
    else:
        form_values = {k: settings[k] for k in ("hostname", "username", "language")}
    return render_template(
        "install/step1.html",
        values=form_values,
        languages=LANGUAGES,
        errors=errors,
    )


@app.route("/install/step2", methods=["GET", "POST"])
def install_step_2():
    if request.method == "POST":
        boot_drive = request.form.get("boot_drive", "").strip()
        if boot_drive:
            settings["boot_drive"] = boot_drive
            return redirect(url_for("install_overview"))
    return render_template(
        "install/step2.html",
        drives=list_scored_devices(),
        selected=settings.get("boot_drive", ""),
    )


@app.route("/install/overview")
def install_overview():
    masked = {**settings, "password": "•" * 8 if settings["password"] else ""}
    return render_template("install/overview.html", settings=masked)


@app.route("/install/run", methods=["POST"])
def install_run():
    if not settings["boot_drive"] or not settings["username"] or not settings["password"]:
        return redirect(url_for("install_step_1"))
    config_path, creds_path = write_install_files(settings, STATE_DIR)
    INSTALL_LOG.write_bytes(b"")
    if os.environ.get("FURTKA_DRY_RUN") == "1":
        INSTALL_LOG.write_text(
            f"DRY RUN: would exec archinstall --config {config_path} "
            f"--creds {creds_path} --silent\n"
        )
    else:
        spawn_archinstall(config_path, creds_path, INSTALL_LOG)
    return redirect(url_for("install_log_view"))


@app.route("/install/log")
def install_log_view():
    log = INSTALL_LOG.read_text() if INSTALL_LOG.exists() else ""
    return render_template(
        "install/log.html",
        log=log,
        progress=parse_install_progress(log),
    )


@app.route("/install/log.json")
def install_log_json():
    log = INSTALL_LOG.read_text() if INSTALL_LOG.exists() else ""
    return jsonify(log=log, progress=parse_install_progress(log))


@app.route("/install/reboot", methods=["POST"])
def install_reboot():
    # Only allow rebooting once the install has actually finished — we don't
    # want a panicked click during install to reboot mid-pacstrap.
    log = INSTALL_LOG.read_text() if INSTALL_LOG.exists() else ""
    if parse_install_progress(log)["status"] != "done":
        return redirect(url_for("install_log_view"))
    # Delay reboot a few seconds so the browser can finish fetching CSS / assets
    # for the rebooting page before the Flask server (and network) go away.
    # Without this, the reboot page renders unstyled (giant inline SVG icon).
    subprocess.Popen(
        ["/bin/sh", "-c", "sleep 3 && /usr/bin/systemctl reboot"],
        start_new_session=True,
    )
    return render_template("install/rebooting.html", hostname=settings["hostname"])


if __name__ == "__main__":
    app.run(debug=True, port=5000)