hexmap/common/src/reducers/HexMapReducer.ts

import {StorageCoordinates} from "../state/Coordinates";
import {areCellsEquivalent, EMPTY_CELL, getCell, HexCell, HexMap} from "../state/HexMap";
import {MapAction} from "../actions/MapAction";
import {CELL_COLOR, CELL_REMOVE} from "../actions/CellAction";

export function updateCell(map: HexMap, coords: StorageCoordinates, newData: Partial<HexCell>): HexMap {
    const oldCell = getCell(map, coords) || EMPTY_CELL;
    return replaceCell(map, coords, {
        ...oldCell,
        ...newData,
    })
}

export function replaceCell(oldMap: HexMap, {line, cell}: StorageCoordinates, newCell: HexCell|null): HexMap {
    if (areCellsEquivalent(getCell(oldMap, {line, cell}), newCell)) {
        return oldMap
    }
    const oldLines = oldMap.layer
    const oldLine = oldLines[line]
    const newLine = [
        ...oldLine.slice(0, cell),
        newCell,
        ...oldLine.slice(cell + 1)
    ]
    const newLines = [
        ...oldLines.slice(0, line),
        newLine,
        ...oldLines.slice(line + 1)
    ]
    return {
        ...oldMap,
        layer: newLines
    }
}

export function hexMapReducer(oldState: HexMap, action: MapAction): HexMap {
    switch (action.type) {
        case CELL_COLOR:
            return updateCell(oldState, action.at, { color: action.color })
        case CELL_REMOVE:
            return replaceCell(oldState, action.at, null)
    }
}