import type { HeatmapConfig } from '../types'

/** Color for the built-in sample types when `sampleColors` has no entry. */
export const DEFAULT_SAMPLE_TYPE_COLORS: Record<string, string> = {
  sample: '#10b981',
  control: '#3b82f6',
  blank: '#f97316',
  qc: '#8b5cf6',
  iqc: '#ec4899',
}

export const HEATMAP_COLORS: Record<string, string[]> = {
  viridis: ['#440154', '#482878', '#3e4989', '#31688e', '#26828e', '#1f9e89', '#35b779', '#6ece58', '#b5de2b', '#fde725'],
  plasma: ['#0d0887', '#46039f', '#7201a8', '#9c179e', '#bd3786', '#d8576b', '#ed7953', '#fb9f3a', '#fdca26', '#f0f921'],
  turbo: ['#30123b', '#4145ab', '#4675ed', '#39a2fc', '#1bcfd4', '#24e79e', '#71f05f', '#c1f034', '#f1c83c', '#f99538', '#e45a31', '#ba2512', '#7a0403'],
}

export function conditionGradientStyle(
  color: string,
  concentration: number,
  concentrations: number[],
): Record<string, string> {
  const min = Math.min(...concentrations)
  const max = Math.max(...concentrations)
  const t = max <= min ? 1 : (concentration - min) / (max - min)
  const opacity = 0.25 + t * 0.50
  const r = parseInt(color.slice(1, 3), 16)
  const g = parseInt(color.slice(3, 5), 16)
  const b = parseInt(color.slice(5, 7), 16)
  const er = 255 * (1 - opacity) + r * opacity
  const eg = 255 * (1 - opacity) + g * opacity
  const eb = 255 * (1 - opacity) + b * opacity
  const luminance = (0.299 * er + 0.587 * eg + 0.114 * eb) / 255
  return {
    backgroundColor: `rgba(${r}, ${g}, ${b}, ${opacity})`,
    color: luminance > 0.55 ? '#1e293b' : '#ffffff',
  }
}

export function formatConcentration(value: number): string {
  if (value >= 1000) return `${value / 1000}k`
  if (value < 0.01) return value.toExponential(0)
  return String(value)
}

export function getHeatmapColor(config: HeatmapConfig | undefined, value: number | undefined): string | null {
  if (!config?.enabled || value === undefined) return null

  const min = config.min ?? 0
  const max = config.max ?? 1
  const normalized = Math.max(0, Math.min(1, (value - min) / (max - min)))
  const colors = config.colorScale === 'custom' && config.customColors?.length
    ? config.customColors
    : HEATMAP_COLORS[config.colorScale || 'viridis']
  const index = Math.min(Math.floor(normalized * (colors.length - 1)), colors.length - 1)
  return colors[index]
}