import { ACTIONS_COLUMN_ID, SELECTION_COLUMN_ID } from '../constants'
import type { GridRangeSelection } from '../types'
import { healSpannedRange, isRangeEqual } from '../utils/range'
import type { ApiSection } from './types'

export type GridRangeSelectionApi = {
    select: (range: null | GridRangeSelection) => void
    move: (direction: 'left' | 'right' | 'up' | 'down') => void
}

export const createRangeSelectionApi: ApiSection<GridRangeSelectionApi> = (
    store,
    events
) => ({
    select(range) {
        events.emit('onRangeSelectionChange', range)
    },
    move: (direction: 'left' | 'right' | 'up' | 'down') => {
        const state = store.getState()
        const rangeSelection = store.selectors.selectRangeSelection(state)
        const currentFocus = store.selectors.selectCurrentFocus(state)

        if (!rangeSelection) return

        const ids = store.selectors.selectRangeIds(state)
        if (
            !ids.rowIds.includes(currentFocus.rowId) ||
            !ids.columnIds.includes(currentFocus.columnId)
        ) {
            return
        }

        const flatIds = store.selectors.selectRowIds(state)
        const columnIds = store.selectors.selectColumnIds(state)

        const rowIndex = flatIds.indexOf(rangeSelection.to.rowId)
        const columnIndex = columnIds.indexOf(rangeSelection.to.columnId)

        const newTo = { ...rangeSelection.to }

        if (direction === 'left') {
            const newColumnId = columnIds[columnIndex - 1]
            if (newColumnId && newColumnId !== SELECTION_COLUMN_ID) {
                newTo.columnId = newColumnId
            }
        } else if (direction === 'right') {
            const newColumnId = columnIds[columnIndex + 1]
            if (newColumnId && newColumnId !== ACTIONS_COLUMN_ID) {
                newTo.columnId = newColumnId
            }
        } else if (direction === 'up') {
            const newRowId = flatIds[rowIndex - 1]
            if (newRowId) {
                newTo.rowId = newRowId
            }
        } else if (direction === 'down') {
            const newRowId = flatIds[rowIndex + 1]
            if (newRowId) {
                newTo.rowId = newRowId
            }
        }

        const newRange = healSpannedRange(
            {
                from: {
                    rowId: currentFocus.rowId,
                    columnId: currentFocus.columnId,
                },
                to: newTo,
            },
            store
        )

        if (!isRangeEqual(rangeSelection, newRange)) {
            events.emit('onRangeSelectionChange', newRange)
        }
    },
})