import type { WindVector } from "./wind.js";
export type WeatherKind = string;
export interface WeatherState {
    kind: WeatherKind;
    intensity: number;
    wind?: WindVector;
}
export interface WeatherModifier {
    grip?: number;
    visibility?: number;
    structureDamage?: number;
    chill?: number;
    ignition?: number;
    spread?: number;
}
export type WeatherModifierTable<K extends string = string> = Record<K, WeatherModifier>;
export type WeatherKindOf<TTable extends WeatherModifierTable> = Extract<keyof TTable, string>;
export interface ResolvedWeather {
    grip: number;
    visibility: number;
    structureDamage: number;
    chill: number;
    ignition: number;
    spread: number;
}
export declare function resolveWeather<TTable extends WeatherModifierTable>(state: WeatherState, table: TTable): ResolvedWeather;
export type FireCellState = "unburnt" | "burning" | "burnt";
export interface FireCell {
    fuel: number;
    heat: number;
    state: FireCellState;
}
export interface FireGridConfig {
    cols: number;
    rows: number;
    cellSize: number;
    /** World x,z of the center of cell (0,0). Default [0,0]. */
    origin?: readonly [number, number];
    /** Initial fuel 0..1 per cell; default 1 everywhere. */
    fuelAt?: (col: number, row: number) => number;
    /** Accumulated heat needed to ignite a fuelled cell. Default 1. */
    ignitionThreshold?: number;
    /** Heat pushed to each neighbour per second from a burning cell. Default 0.6. */
    spreadRate?: number;
    /** Fuel consumed per second while burning. Default 0.25. */
    burnRate?: number;
    /** Prevailing wind biasing spread direction. */
    wind?: WindVector;
    /** How strongly wind biases downwind vs upwind spread, 0..1. Default 0.6. */
    windBias?: number;
    /** Hard allocation bound; defaults to 65536 cells. */
    maxCells?: number;
}
/** Live fire ignition, spread, consumption and wind policies; grid geometry stays fixed. */
export type FireGridTuning = Pick<FireGridConfig, "ignitionThreshold" | "spreadRate" | "burnRate" | "wind" | "windBias">;
export interface FireStepOptions {
    /** Global spread multiplier this step (rain suppression from resolveWeather().spread). Default 1. */
    spread?: number;
    /** Live wind in metres/second along world X,Z, overriding configured wind this step. */
    wind?: WindVector;
    windAt?: (x: number, z: number) => WindVector;
    /** Per-cell wetness 0..1 that resists ignition — from an environment field. */
    wetnessAt?: (col: number, row: number) => number;
    /** Heat removed per second at full wetness; 0 (default) leaves extinction to game policy. */
    extinguishRate?: number;
}
export interface FireGrid {
    readonly cols: number;
    readonly rows: number;
    readonly cellSize: number;
    readonly origin: readonly [number, number];
    /** Advance the cellular propagation by game-time `dt`. */
    step(dt: number, options?: FireStepOptions): void;
    igniteCell(col: number, row: number): void;
    /** Cool a burning cell to unburnt without replacing its remaining fuel. */
    extinguishCell(col: number, row: number): boolean;
    /** Extinguish the cell under a world position; false outside the grid or when not burning. */
    extinguish(x: number, z: number): boolean;
    /** Ignite the cell under a world position; no-op if outside the grid. */
    ignite(x: number, z: number): boolean;
    cell(col: number, row: number): FireCell;
    cellAt(x: number, z: number): FireCell | null;
    cellCoord(x: number, z: number): {
        col: number;
        row: number;
    } | null;
    /** Count of currently burning cells. */
    readonly burning: number;
    /** Flat snapshot (row-major) for rendering. */
    snapshot(): FireCell[];
    restore(state: readonly FireCell[]): void;
    retune(tuning: FireGridTuning): void;
}
export declare function createFireGrid(config: FireGridConfig): FireGrid;