from __future__ import annotations

from typing import Any, Dict, List, Tuple

TOP_KEYS = ["ui", "hmis", "plcs", "sensors", "actuators", "hils", "serial_networks", "ip_networks"]


def validate_basic(cfg: dict[str, Any]) -> List[str]:
    errors: List[str] = []

    if not isinstance(cfg, dict):
        return ["Top-level JSON is not an object"]

    for k in TOP_KEYS:
        if k not in cfg:
            errors.append(f"Missing top-level key: {k}")
    if errors:
        return errors

    if not isinstance(cfg["ui"], dict):
        errors.append("ui must be an object")

    for k in ["hmis", "plcs", "sensors", "actuators", "hils", "serial_networks", "ip_networks"]:
        if not isinstance(cfg[k], list):
            errors.append(f"{k} must be an array")
    if errors:
        return errors

    ui = cfg.get("ui", {})
    if not isinstance(ui, dict):
        errors.append("ui must be an object")
        return errors
    uinet = ui.get("network")
    if not isinstance(uinet, dict):
        errors.append("ui.network must be an object")
        return errors
    for req in ["ip", "port", "docker_network"]:
        if req not in uinet:
            errors.append(f"ui.network missing key: {req}")

    names: List[str] = []
    for section in ["hmis", "plcs", "sensors", "actuators", "hils"]:
        for dev in cfg.get(section, []):
            if isinstance(dev, dict) and isinstance(dev.get("name"), str):
                names.append(dev["name"])
    dup = {n for n in set(names) if names.count(n) > 1}
    if dup:
        errors.append(f"Duplicate device names: {sorted(list(dup))}")

    seen: Dict[Tuple[str, str], str] = {}

    def check_net(dev: dict[str, Any]) -> None:
        net = dev.get("network") or {}
        dn = net.get("docker_network")
        ip = net.get("ip")
        name = dev.get("name", "<unnamed>")
        if not isinstance(dn, str) or not isinstance(ip, str):
            return
        key = (dn, ip)
        if key in seen:
            errors.append(f"Duplicate IP {ip} on docker_network {dn} (devices: {seen[key]} and {name})")
        else:
            seen[key] = str(name)

    for section in ["hmis", "plcs", "sensors", "actuators"]:
        for dev in cfg.get(section, []):
            if isinstance(dev, dict):
                check_net(dev)

    def uses_rtu(dev: dict[str, Any]) -> bool:
        for c in (dev.get("inbound_connections") or []):
            if isinstance(c, dict) and c.get("type") == "rtu":
                return True
        for c in (dev.get("outbound_connections") or []):
            if isinstance(c, dict) and c.get("type") == "rtu":
                return True
        return False

    any_rtu = False
    for section in ["hmis", "plcs", "sensors", "actuators"]:
        for dev in cfg.get(section, []):
            if isinstance(dev, dict) and uses_rtu(dev):
                any_rtu = True

    serial_nets = cfg.get("serial_networks", [])
    if any_rtu and len(serial_nets) == 0:
        errors.append("RTU used but serial_networks is empty")
    if (not any_rtu) and len(serial_nets) != 0:
        errors.append("serial_networks must be empty when RTU is not used")

    return errors