import type { DatePreset, ExperimentStatus, SelectOption, PillVariant } from '../types'

interface ExperimentCodeSource {
  id?: number | null
  experiment_code?: string | null
}

export function formatExperimentDate(dateStr: string): string {
  try {
    return new Date(dateStr).toLocaleDateString(undefined, {
      year: 'numeric',
      month: 'short',
      day: 'numeric',
    })
  } catch {
    return dateStr
  }
}

export function datePresetToISO(preset: DatePreset): string {
  const now = new Date()
  const days = preset === 'last_7_days' ? 7 : preset === 'last_30_days' ? 30 : 90
  const d = new Date(now.getTime() - days * 86_400_000)
  return d.toISOString()
}

export const EXPERIMENT_STATUS_OPTIONS: SelectOption<string>[] = [
  { value: '', label: 'All statuses' },
  { value: 'planned', label: 'Planned' },
  { value: 'ongoing', label: 'Ongoing' },
  { value: 'completed', label: 'Completed' },
  { value: 'cancelled', label: 'Cancelled' },
]

export const EXPERIMENT_STATUS_VARIANT_MAP: Record<ExperimentStatus, PillVariant> = {
  planned: 'default',
  ongoing: 'primary',
  completed: 'success',
  cancelled: 'error',
}

export const EXPERIMENT_STATUS_LABELS: Record<ExperimentStatus, string> = {
  planned: 'Planned',
  ongoing: 'Ongoing',
  completed: 'Completed',
  cancelled: 'Cancelled',
}

export function formatExperimentStatus(status?: ExperimentStatus | string | null): string {
  if (!status) return ''
  if (status in EXPERIMENT_STATUS_LABELS) {
    return EXPERIMENT_STATUS_LABELS[status as ExperimentStatus]
  }
  const label = String(status).replace(/[-_]+/g, ' ').trim()
  return label ? label.replace(/^\w/, c => c.toUpperCase()) : ''
}

export function getExperimentStatusVariant(status?: ExperimentStatus | string | null): PillVariant {
  if (status && status in EXPERIMENT_STATUS_VARIANT_MAP) {
    return EXPERIMENT_STATUS_VARIANT_MAP[status as ExperimentStatus]
  }
  return 'default'
}

export function resolveExperimentCode(experiment: ExperimentCodeSource): string | undefined {
  if (experiment.experiment_code) return experiment.experiment_code
  return undefined
}

// Mirrors vue-router's LocationQuery, whose array members are `string | null`.
// Declaring `string[]` here made the helper reject the very type every caller
// passes it, so keep this assignable from LocationQuery without importing
// vue-router (the SDK does not depend on it).
type RouteQueryValue = string | null | undefined | readonly (string | null | undefined)[]
type RouteQueryLike = Record<string, RouteQueryValue>

/**
 * Reads the experiment id a deep link was opened with.
 *
 * Returns an id and never a label: a display name belongs to the platform, so
 * callers must resolve it (see `useExperimentStore().selectById`) rather than
 * derive one from the query or the id itself.
 */
export function experimentIdFromRoute(query: RouteQueryLike): number | null {
  const raw = query.experiment_id ?? query.experimentId
  const value = Array.isArray(raw) ? raw.find(item => typeof item === 'string') : raw
  if (typeof value !== 'string' || !value) return null
  const id = Number(value)
  return Number.isInteger(id) && id > 0 ? id : null
}

export const DATE_PRESET_OPTIONS: SelectOption<string>[] = [
  { value: '', label: 'Any time' },
  { value: 'last_7_days', label: 'Last 7 days' },
  { value: 'last_30_days', label: 'Last 30 days' },
  { value: 'last_90_days', label: 'Last 90 days' },
]

export const SORT_OPTIONS: SelectOption<string>[] = [
  { value: 'created_at:desc', label: 'Newest first' },
  { value: 'created_at:asc', label: 'Oldest first' },
  { value: 'updated_at:desc', label: 'Recently updated' },
  { value: 'name:asc', label: 'Name A\u2013Z' },
  { value: 'name:desc', label: 'Name Z\u2013A' },
]