import type { Theme } from '@mui/material'

/**
 * Resolve a colour string against the MUI theme palette.
 *
 * - `'primary.main'`, `'secondary.dark'`, `'success.contrastText'`, … →
 *   walks `theme.palette` along the dot-separated path and returns the
 *   resolved string when traversal succeeds.
 * - `'#ff0000'`, `'rgb(255, 0, 0)'`, `'red'` → returned as-is (assumed
 *   raw CSS; ECharts consumes them directly).
 * - `undefined` → `undefined` (callers fall back to ECharts' palette).
 *
 * Used by the echart option factories (Bar, Pie, Histogram, Scatterplot,
 * Timeseries) so per-series colours specified as theme paths in the
 * unified `WidgetSeries` shape paint correctly. Category, Formula, and
 * Spread render colours through MUI's `sx` resolver, which already
 * handles theme paths — they don't need this helper.
 */
export function resolveThemeColor(
  theme: Theme,
  raw: string | undefined,
): string | undefined {
  if (raw == null) return undefined
  if (!raw.includes('.')) return raw
  const parts = raw.split('.')
  let cursor: unknown = theme.palette
  for (const part of parts) {
    if (cursor == null || typeof cursor !== 'object') {
      return raw
    }
    cursor = (cursor as Record<string, unknown>)[part]
  }
  return typeof cursor === 'string' ? cursor : raw
}