"""GODSEED tool DSL — the single source of truth for the 11-tool surface.

Spec is data (TOOLS); validation is `validate_call`. Semantics per the
architecture contract:

* out-of-range NUMBERS are CLAMPED, never rejected;
* unknown tools / unknown enum values are REJECTED with a terse observation
  string the model can react to (e.g. "rejected: unknown kind 'cactus'");
* missing or non-numeric/malformed args are rejected (they cannot be clamped);
* extra args not in the spec are silently dropped.

`place_water` constraints: kind "stream" needs 2..5 path waypoints and takes
no radius; kind "pool" uses path[0] as its center and requires radius_deg.
`place_road` takes a path of 2..6 [lat,lon] waypoints (a paved surface spline).

Pure stdlib. Other engine modules (and the mind's prompt builder) import this.
"""

from __future__ import annotations

import math
from dataclasses import dataclass
from typing import Any, Optional

LAT_RANGE = (-85.0, 85.0)
LON_RANGE = (-180.0, 180.0)


@dataclass(frozen=True)
class NumberSpec:
    lo: float
    hi: float
    integer: bool = False


@dataclass(frozen=True)
class EnumSpec:
    values: tuple[str, ...]


@dataclass(frozen=True)
class TextSpec:
    max_len: int


@dataclass(frozen=True)
class PathSpec:
    max_points: int = 5


FLORA_KINDS = ("trees", "glowgrass", "mushrooms", "vines", "flowers", "reeds")
STRUCTURE_KINDS = (
    "lighthouse", "monolith", "shrine", "village", "beacon", "arch",
    "tower", "warehouse", "cafe", "bank", "market", "house",
)
# The god (a 9B model, no grammar constraint on the live ZeroGPU path) invents
# building names freely — "market_square", "skyscraper", "townhall". REJECTING
# them makes a town wish build nothing and the model gives up (June 12 live:
# "it says it created the town... there is no town"). So place_structure is
# FORGIVING: synonyms map to a real kind, and any unknown kind falls back to a
# house rather than failing. The god always builds something.
STRUCTURE_SYNONYMS: dict[str, str] = {
    "market_square": "market", "marketsquare": "market", "square": "market",
    "plaza": "market", "bazaar": "market", "marketplace": "market", "stall": "market",
    "skyscraper": "tower", "highrise": "tower", "high_rise": "tower", "office": "tower",
    "spire": "tower", "obelisk": "monolith", "pillar": "monolith", "stone": "monolith",
    "depot": "warehouse", "storehouse": "warehouse", "storage": "warehouse",
    "factory": "warehouse", "barn": "warehouse", "silo": "warehouse",
    "coffee": "cafe", "coffeehouse": "cafe", "restaurant": "cafe", "diner": "cafe",
    "cafeteria": "cafe", "inn": "cafe", "tavern": "cafe", "pub": "cafe", "bakery": "cafe",
    "home": "house", "cottage": "house", "cabin": "house", "hut": "house", "lodge": "house",
    "dwelling": "house", "residence": "house", "bungalow": "house", "manor": "house",
    "church": "shrine", "temple": "shrine", "chapel": "shrine", "cathedral": "shrine",
    "townhall": "bank", "town_hall": "bank", "hall": "bank", "courthouse": "bank",
    "library": "bank", "museum": "bank", "school": "bank", "guildhall": "bank",
    "harbor": "lighthouse", "harbour": "lighthouse", "port": "lighthouse", "dock": "lighthouse",
    "gate": "arch", "gateway": "arch", "bridge": "arch", "tower_gate": "arch",
    "fire": "beacon", "torch": "beacon", "lantern": "beacon", "lamp": "beacon",
    "hamlet": "village", "settlement": "village", "houses": "village",
}
# Kinds that really mean "a whole neighborhood" -> the engine routes them to a
# dense build_district instead of a single building, so the town reads dense.
DISTRICT_SYNONYMS = frozenset((
    "district", "neighborhood", "neighbourhood", "block", "quarter", "town",
    "city", "downtown", "suburb", "metropolis", "borough", "ward",
))


def resolve_structure_kind(value: Any) -> str | None:
    """Map a model-supplied kind to a real STRUCTURE_KINDS value. None means
    'this is really a district' (caller should route to build_district).
    Unknown-but-buildingish names fall back to 'house' — never a rejection."""
    if not isinstance(value, str):
        return "house"
    v = value.strip().lower().replace(" ", "_").replace("-", "_")
    if v in STRUCTURE_KINDS:
        return v
    if v in DISTRICT_SYNONYMS:
        return None
    if v in STRUCTURE_SYNONYMS:
        return STRUCTURE_SYNONYMS[v]
    # substring rescue (e.g. "grand_market_hall" -> market) before defaulting
    for token, kind in STRUCTURE_SYNONYMS.items():
        if token in v:
            return kind
    for kind in STRUCTURE_KINDS:
        if kind in v:
            return kind
    return "house"  # any other word becomes a humble house, never a rejection


WATER_KINDS = ("stream", "pool")
WEATHER_KINDS = ("clear", "rain", "snow", "embers", "mist", "storm")
SKY_PALETTES = ("dawn", "dusk", "night", "aurora", "ember", "void", "gold")
INSCRIBE_STYLES = ("orbit", "stone")
LIFE_KINDS = ("carts", "birds", "fireflies")

TOOLS: dict[str, dict[str, Any]] = {
    "raise_terrain": {
        "lat": NumberSpec(*LAT_RANGE),
        "lon": NumberSpec(*LON_RANGE),
        "radius_deg": NumberSpec(2, 45),
        "height": NumberSpec(0.01, 0.12),
        "roughness": NumberSpec(0, 1),
    },
    "lower_terrain": {
        "lat": NumberSpec(*LAT_RANGE),
        "lon": NumberSpec(*LON_RANGE),
        "radius_deg": NumberSpec(2, 45),
        "depth": NumberSpec(0.01, 0.10),
        "roughness": NumberSpec(0, 1),
    },
    "spawn_flora": {
        "lat": NumberSpec(*LAT_RANGE),
        "lon": NumberSpec(*LON_RANGE),
        "radius_deg": NumberSpec(1, 30),
        "kind": EnumSpec(FLORA_KINDS),
        "density": NumberSpec(0, 1),
        "hue": NumberSpec(0, 360),
    },
    "place_structure": {
        "lat": NumberSpec(*LAT_RANGE),
        "lon": NumberSpec(*LON_RANGE),
        "kind": EnumSpec(STRUCTURE_KINDS),
        "scale": NumberSpec(0.5, 2.0),
        "hue": NumberSpec(0, 360),
    },
    "place_water": {
        "kind": EnumSpec(WATER_KINDS),
        "path": PathSpec(5),
        "radius_deg": NumberSpec(1, 10),  # pool only
        "hue": NumberSpec(160, 260),
    },
    "set_weather": {
        "kind": EnumSpec(WEATHER_KINDS),
        "intensity": NumberSpec(0, 1),
    },
    "set_sky": {
        "palette": EnumSpec(SKY_PALETTES),
        "star_density": NumberSpec(0, 1),
        "moons": NumberSpec(0, 3, integer=True),
    },
    "inscribe_wish": {
        "text": TextSpec(90),
        "style": EnumSpec(INSCRIBE_STYLES),
    },
    "spawn_life": {
        "lat": NumberSpec(*LAT_RANGE),
        "lon": NumberSpec(*LON_RANGE),
        "radius_deg": NumberSpec(1, 20),
        "kind": EnumSpec(LIFE_KINDS),
        "count": NumberSpec(1, 12, integer=True),
        "hue": NumberSpec(0, 360),
    },
    "build_district": {
        "lat": NumberSpec(*LAT_RANGE),
        "lon": NumberSpec(*LON_RANGE),
        "radius_deg": NumberSpec(2, 15),
        "density": NumberSpec(0, 1),
        "hue": NumberSpec(0, 360),
    },
    "place_road": {
        "path": PathSpec(6),  # 2..6 [lat,lon] waypoints
    },
}

TOOL_NAMES: tuple[str, ...] = tuple(TOOLS.keys())


def _snip(value: Any) -> str:
    """Terse, single-line render of a bad value for observation strings."""
    s = str(value)
    s = "".join(ch if ch.isprintable() else "?" for ch in s)
    return s[:32]


def _coerce_number(name: str, value: Any, spec: NumberSpec):
    """Returns (clamped_value, None) or (None, rejection)."""
    if isinstance(value, bool):
        return None, f"rejected: bad arg '{name}'"
    if isinstance(value, str):
        try:
            value = float(value.strip())
        except (ValueError, AttributeError):
            return None, f"rejected: bad arg '{name}'"
    if not isinstance(value, (int, float)):
        return None, f"rejected: bad arg '{name}'"
    v = float(value)
    if math.isnan(v):
        return None, f"rejected: bad arg '{name}'"
    v = min(max(v, float(spec.lo)), float(spec.hi))
    if spec.integer:
        return int(round(v)), None
    return round(v, 4), None


def _coerce_enum(name: str, value: Any, spec: EnumSpec):
    if not isinstance(value, str):
        return None, f"rejected: unknown {name} '{_snip(value)}'"
    v = value.strip().lower()
    if v not in spec.values:
        return None, f"rejected: unknown {name} '{_snip(value)}'"
    return v, None


def _coerce_text(name: str, value: Any, spec: TextSpec):
    if not isinstance(value, str):
        return None, f"rejected: bad arg '{name}'"
    v = "".join(ch for ch in value if ch.isprintable()).strip()
    if not v:
        return None, f"rejected: empty {name}"
    return v[: spec.max_len], None


def _coerce_point(point: Any):
    """A waypoint is [lat, lon] (or {'lat':..,'lon':..}); returns [lat, lon] or None."""
    if isinstance(point, dict):
        raw = (point.get("lat"), point.get("lon"))
    elif isinstance(point, (list, tuple)) and len(point) >= 2:
        raw = (point[0], point[1])
    else:
        return None
    lat, err = _coerce_number("lat", raw[0], NumberSpec(*LAT_RANGE))
    if err:
        return None
    lon, err = _coerce_number("lon", raw[1], NumberSpec(*LON_RANGE))
    if err:
        return None
    return [lat, lon]


DEFAULT_WATER_HUE = 190.0
DEFAULT_POOL_RADIUS = 5.0


def _validate_place_water(args: dict):
    """Models fumble water more than any other tool (June 12 live traces), so
    this one is deliberately forgiving: lat/lon synthesize a path, a flat
    [lat, lon] pair is wrapped, and hue / pool radius take engine defaults."""
    spec = TOOLS["place_water"]
    kind, err = _coerce_enum("kind", args.get("kind"), spec["kind"])
    if err:
        return None, err

    raw_path = args.get("path")
    # lat/lon supplied like every other tool -> a one-point path
    if not isinstance(raw_path, (list, tuple)) or not raw_path:
        if args.get("lat") is not None and args.get("lon") is not None:
            raw_path = [[args.get("lat"), args.get("lon")]]
        else:
            return None, "rejected: water needs path [[lat,lon],...] or lat+lon"
    # a flat [lat, lon] pair instead of [[lat, lon]]
    if raw_path and not isinstance(raw_path[0], (list, tuple)):
        raw_path = [raw_path]
    points = []
    for p in list(raw_path)[: spec["path"].max_points]:  # extra waypoints clamped off
        pt = _coerce_point(p)
        if pt is None:
            return None, "rejected: bad waypoint in path (each is [lat, lon])"
        points.append(pt)

    hue_raw = args.get("hue")
    if hue_raw is None:
        hue = DEFAULT_WATER_HUE
    else:
        hue, err = _coerce_number("hue", hue_raw, spec["hue"])
        if err:
            return None, err

    if kind == "stream":
        if len(points) < 2:
            return None, "rejected: stream needs 2..5 waypoints"
        return {"kind": "stream", "path": points, "hue": hue}, None

    # pool: path[0] is the center; radius defaults rather than dies
    radius_raw = args.get("radius_deg")
    if radius_raw is None:
        radius = DEFAULT_POOL_RADIUS
    else:
        radius, err = _coerce_number("radius_deg", radius_raw, spec["radius_deg"])
        if err:
            return None, err
    return {"kind": "pool", "path": points[:1], "radius_deg": radius, "hue": hue}, None


def _validate_place_road(args: dict):
    """A road is a paved surface spline through 2..6 [lat,lon] waypoints.

    Path handling mirrors place_water (a flat [lat, lon] pair is wrapped; extra
    waypoints past the max are clamped off) but a road always needs at least two
    points — there is no single-point form.
    """
    spec = TOOLS["place_road"]
    raw_path = args.get("path")
    if not isinstance(raw_path, (list, tuple)) or not raw_path:
        return None, "rejected: road needs path [[lat,lon],...] (2..6 points)"
    # a flat [lat, lon] pair instead of [[lat, lon]]
    if not isinstance(raw_path[0], (list, tuple, dict)):
        raw_path = [raw_path]
    points = []
    for p in list(raw_path)[: spec["path"].max_points]:  # extra waypoints clamped off
        pt = _coerce_point(p)
        if pt is None:
            return None, "rejected: bad waypoint in path (each is [lat, lon])"
        points.append(pt)
    if len(points) < 2:
        return None, "rejected: road needs 2..6 waypoints"
    return {"path": points}, None


def validate_call(tool: Any, args: Any) -> tuple[Optional[dict], Optional[str]]:
    """Validate one tool call. Returns (canonical_args, None) or (None, rejection).

    Canonical args contain exactly the spec'd keys (in spec order), with
    numbers clamped + rounded, enums lowercased, text sanitized/truncated.
    """
    if not isinstance(tool, str) or tool not in TOOLS:
        return None, f"rejected: unknown tool '{_snip(tool)}'"
    if args is None:
        args = {}
    if not isinstance(args, dict):
        return None, "rejected: args must be an object"
    if tool == "place_water":
        return _validate_place_water(args)
    if tool == "place_road":
        return _validate_place_road(args)

    # place_structure: forgive the kind. A "district"-ish name becomes a dense
    # build_district; any other unknown becomes the nearest real building (or a
    # house) — the god never builds nothing because it picked a word we lack.
    if tool == "place_structure":
        resolved = resolve_structure_kind(args.get("kind"))
        if resolved is None:
            district_args = {
                "lat": args.get("lat"), "lon": args.get("lon"),
                "radius_deg": args.get("radius_deg", 6),
                "density": args.get("density", 0.7),
                "hue": args.get("hue", 40),
            }
            return validate_call("build_district", district_args)
        args = {**args, "kind": resolved}

    out: dict[str, Any] = {}
    for name, spec in TOOLS[tool].items():
        if name not in args or args.get(name) is None:
            return None, f"rejected: missing arg '{name}'"
        value = args[name]
        if isinstance(spec, NumberSpec):
            v, err = _coerce_number(name, value, spec)
        elif isinstance(spec, EnumSpec):
            v, err = _coerce_enum(name, value, spec)
        elif isinstance(spec, TextSpec):
            v, err = _coerce_text(name, value, spec)
        else:  # pragma: no cover — only place_water has PathSpec, handled above
            v, err = None, f"rejected: bad arg '{name}'"
        if err:
            return None, err
        out[name] = v
    return out, None


# Per-tool minimum path length (place_water's pool form accepts a single
# center point; place_road always needs at least two waypoints).
_PATH_MIN_POINTS: dict[str, int] = {"place_water": 1, "place_road": 2}


def as_dict() -> dict:
    """Plain-JSON view of the tool spec (handy for prompts / grammar builders)."""
    out: dict[str, dict] = {}
    for tool, argspecs in TOOLS.items():
        spec_out: dict[str, dict] = {}
        for name, spec in argspecs.items():
            if isinstance(spec, NumberSpec):
                spec_out[name] = {
                    "type": "number", "min": spec.lo, "max": spec.hi,
                    "integer": spec.integer,
                }
            elif isinstance(spec, EnumSpec):
                spec_out[name] = {"type": "enum", "values": list(spec.values)}
            elif isinstance(spec, TextSpec):
                spec_out[name] = {"type": "string", "max_len": spec.max_len}
            elif isinstance(spec, PathSpec):
                spec_out[name] = {
                    "type": "path",
                    "min_points": _PATH_MIN_POINTS.get(tool, 1),
                    "max_points": spec.max_points,
                    "point": "[lat, lon]",
                }
        out[tool] = spec_out
    out["place_water"]["radius_deg"]["note"] = "pool only"
    out["place_water"]["path"]["note"] = "stream: 2..5 waypoints; pool: path[0] is center"
    out["place_road"]["path"]["note"] = "2..6 waypoints; a paved road laid on the surface"
    return out