"""Provisioning orchestrator: ties ZFS, DB, secrets, render, SFTP and compose
into the provision / deprovision flows described in docs/05-provisioning-workflow.md.
"""
from __future__ import annotations

from pathlib import Path

import yaml

from . import backup, compose, database, render, secrets, sftp, zfs
from .config import Config, Site
from .runner import Runner

SITE_FIELDS = ("customer", "site", "profile", "domains", "php_version",
               "database", "redirect_to", "redirect_code", "resources")


def deployment_dir(cfg: Config, site: Site) -> Path:
    return cfg.deployments_dir / site.customer / site.site


def _site_to_dict(site: Site) -> dict:
    return {f: getattr(site, f) for f in SITE_FIELDS}


def provision(cfg: Config, site: Site, runner: Runner) -> dict:
    """Provision a site end-to-end. Idempotent where the underlying steps are."""
    deploy_dir = deployment_dir(cfg, site)
    summary: dict = {"slug": site.slug, "deploy_dir": str(deploy_dir)}

    # 1. Storage
    zfs.create_web(runner, cfg, site)
    sftp.set_web_ownership(runner, cfg, site)

    # 2. Database + secrets (only for DB profiles)
    if site.database:
        db_password = secrets.generate_password()
        database.create_db_user(runner, cfg, site, db_password)
        secrets.write_env(runner, deploy_dir, {secrets.db_env_key(site): db_password})
        secrets.encrypt_env(runner, cfg, deploy_dir)

    # 3. Render compose + nginx config + persist site.yaml (source of truth)
    for name, content in render.render(cfg, site).items():
        runner.write_file(deploy_dir / name, content)
    runner.write_file(deploy_dir / "site.yaml",
                      yaml.safe_dump(_site_to_dict(site), sort_keys=False))

    # 4. SFTP (per customer; password only set when the account is first created)
    sftp_password = secrets.generate_password()
    created = sftp.ensure_customer_account(runner, cfg, site.customer, sftp_password)
    summary["sftp_user"] = f"sftp_{site.customer}"
    summary["sftp_password"] = sftp_password if created else None

    # 5. Deploy
    compose.up(runner, deploy_dir)
    return summary


def deprovision(cfg: Config, site: Site, runner: Runner, *,
                purge: bool = False, final_backup: bool = True) -> dict:
    """Tear down a site. Data is destroyed only with ``purge=True`` and always
    after a final backup.
    """
    deploy_dir = deployment_dir(cfg, site)
    summary: dict = {"slug": site.slug, "purged": purge}

    compose.down(runner, deploy_dir)

    if final_backup:
        summary["final_backup"] = backup.backup_site(runner, cfg, site)

    if site.database:
        database.drop_db_user(runner, cfg, site)

    if purge:
        # Destroy the site dataset (its /web child included) but keep the customer
        # dataset + SFTP account — other sites may still belong to this customer.
        zfs.destroy(runner, f"{cfg.pool}/customers/{site.customer}/{site.site}")
        runner.run(["rm", "-rf", str(deploy_dir)])
        summary["data_destroyed"] = True
    else:
        summary["data_destroyed"] = False
        summary["note"] = "config/containers removed; data retained. Re-run with purge to delete."
    return summary