1 files changed, 175 insertions, 0 deletions
diff --git a/jprov/config.py b/jprov/config.py
new file mode 100644
index 0000000..e7fc504
--- /dev/null
+++ b/jprov/config.py
@@ -0,0 +1,175 @@
+"""Configuration loading and validation."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+import os
+from typing import Any
+
+import tomllib
+
+
+@dataclass
+class MainConfig:
+    base_dir: str
+    templates_prefix: str
+    containers_prefix: str
+    jail_conf_dir: str
+    log_dir: str
+
+
+@dataclass
+class Mount:
+    host: str
+    jail: str
+    readonly: bool = False
+
+
+@dataclass
+class JailConfig:
+    name: str
+    template: str
+    cmd: str
+    overlay: str | None
+    mounts: list[Mount]
+    env: dict[str, str]
+    extra_jail_conf: str | None
+
+
+class ConfigError(RuntimeError):
+    pass
+
+
+def load_main_config() -> MainConfig:
+    """Load main config from /usr/local/etc/jprov.conf or /etc/jprov.conf."""
+    candidates = ["/usr/local/etc/jprov.conf", "/etc/jprov.conf"]
+    path = next((p for p in candidates if os.path.exists(p)), None)
+    if not path:
+        raise ConfigError("main config not found (expected /usr/local/etc/jprov.conf or /etc/jprov.conf)")
+
+    with open(path, "rb") as fh:
+        data = tomllib.load(fh)
+
+    try:
+        base_dir = data["base_dir"]
+        datasets = data["datasets"]
+        templates_prefix = datasets["templates_prefix"]
+        containers_prefix = datasets["containers_prefix"]
+        jail_conf_dir = data["jail_conf_dir"]
+        log_dir = data["log_dir"]
+    except KeyError as exc:
+        raise ConfigError(f"missing main config key: {exc}") from exc
+
+    for key, val in [
+        ("base_dir", base_dir),
+        ("templates_prefix", templates_prefix),
+        ("containers_prefix", containers_prefix),
+        ("jail_conf_dir", jail_conf_dir),
+        ("log_dir", log_dir),
+    ]:
+        if not isinstance(val, str) or not val:
+            raise ConfigError(f"invalid main config value for {key}")
+
+    if not templates_prefix.endswith("/"):
+        raise ConfigError("datasets.templates_prefix must end with '/'")
+    if not containers_prefix.endswith("/"):
+        raise ConfigError("datasets.containers_prefix must end with '/'")
+
+    return MainConfig(
+        base_dir=base_dir,
+        templates_prefix=templates_prefix,
+        containers_prefix=containers_prefix,
+        jail_conf_dir=jail_conf_dir,
+        log_dir=log_dir,
+    )
+
+
+def load_jail_config(main: MainConfig, jailname: str) -> JailConfig:
+    """Load per-jail TOML config for the given jail name."""
+    jail_dir = os.path.join(main.base_dir, "defs", jailname)
+    path = os.path.join(jail_dir, "jprov.conf")
+    if not os.path.exists(path):
+        raise ConfigError(f"jail config not found: {path}")
+
+    with open(path, "rb") as fh:
+        data = tomllib.load(fh)
+
+    try:
+        template = data["template"]
+        cmd = data["cmd"]
+    except KeyError as exc:
+        raise ConfigError(f"missing jail config key: {exc}") from exc
+
+    overlay = data.get("overlay")
+    env = data.get("env", {})
+    extra_jail_conf = data.get("extra_jail_conf")
+    mounts_raw = data.get("mounts", [])
+
+    if not isinstance(template, str) or not template:
+        raise ConfigError("invalid jail config template")
+    if not isinstance(cmd, str) or not cmd:
+        raise ConfigError("invalid jail config cmd")
+    if overlay is not None and not isinstance(overlay, str):
+        raise ConfigError("invalid jail config overlay")
+    if env and not isinstance(env, dict):
+        raise ConfigError("invalid jail config env")
+    if extra_jail_conf is not None and not isinstance(extra_jail_conf, str):
+        raise ConfigError("invalid jail config extra_jail_conf")
+    if mounts_raw and not isinstance(mounts_raw, list):
+        raise ConfigError("invalid jail config mounts")
+
+    mounts: list[Mount] = []
+    for item in mounts_raw:
+        if not isinstance(item, dict):
+            raise ConfigError("invalid mount entry")
+        try:
+            host = item["host"]
+            jail = item["jail"]
+        except KeyError as exc:
+            raise ConfigError(f"missing mount key: {exc}") from exc
+        readonly = bool(item.get("readonly", False))
+        if not isinstance(host, str) or not isinstance(jail, str):
+            raise ConfigError("invalid mount host/jail")
+        mounts.append(Mount(host=host, jail=jail, readonly=readonly))
+
+    return JailConfig(
+        name=jailname,
+        template=template,
+        cmd=cmd,
+        overlay=overlay,
+        mounts=mounts,
+        env={str(k): str(v) for k, v in env.items()} if env else {},
+        extra_jail_conf=extra_jail_conf,
+    )
+
+
+def validate_configs(main: MainConfig, jail: JailConfig) -> None:
+    """Validate referenced paths and dataset names exist."""
+    if not os.path.isdir(main.base_dir):
+        raise ConfigError(f"base_dir does not exist: {main.base_dir}")
+
+    jail_dir = os.path.join(main.base_dir, "defs", jail.name)
+    if not os.path.isdir(jail_dir):
+        raise ConfigError(f"jail defs dir does not exist: {jail_dir}")
+
+    overlay_path = resolve_overlay_path(main, jail)
+    if overlay_path and not os.path.isdir(overlay_path):
+        raise ConfigError(f"overlay dir does not exist: {overlay_path}")
+
+    for mnt in jail.mounts:
+        if not os.path.exists(mnt.host):
+            raise ConfigError(f"mount host path does not exist: {mnt.host}")
+
+
+def resolve_overlay_path(main: MainConfig, jail: JailConfig) -> str:
+    """Return resolved overlay path for the jail."""
+    if jail.overlay is None or jail.overlay == "":
+        return os.path.join(main.base_dir, "defs", jail.name, "overlay")
+    if os.path.isabs(jail.overlay):
+        return jail.overlay
+    return os.path.join(main.base_dir, "defs", jail.name, jail.overlay)
+
+
+def jail_conf_path(main: MainConfig, jailname: str) -> str:
+    """Return path to the generated jail.conf.d file for this jail."""
+    return os.path.join(main.jail_conf_dir, f"{jailname}.conf")