import type { StatusBadgeProps } from '@/components/status-badge'
import {
  BILLING_PRICING_VARS,
  parseTiersFromExpr,
  type ParsedTier,
} from '@/features/pricing/lib/billing-expr'
import type { UsageLog } from '../data/schema'
import type { LogOtherData } from '../types'

const PARAM_OVERRIDE_ACTION_MAP: Record<string, string> = {
  set: 'Set',
  delete: 'Delete',
  copy: 'Copy',
  move: 'Move',
  append: 'Append',
  prepend: 'Prepend',
  trim_prefix: 'Trim Prefix',
  trim_suffix: 'Trim Suffix',
  ensure_prefix: 'Ensure Prefix',
  ensure_suffix: 'Ensure Suffix',
  trim_space: 'Trim Space',
  to_lower: 'To Lower',
  to_upper: 'To Upper',
  replace: 'Replace',
  regex_replace: 'Regex Replace',
  set_header: 'Set Header',
  delete_header: 'Delete Header',
  copy_header: 'Copy Header',
  move_header: 'Move Header',
  pass_headers: 'Pass Headers',
  sync_fields: 'Sync Fields',
  return_error: 'Return Error',
}

/**
 * Get localized label for a param override action
 */
export function getParamOverrideActionLabel(
  action: string,
  t: (key: string) => string
): string {
  const key = PARAM_OVERRIDE_ACTION_MAP[action.toLowerCase()]
  return key ? t(key) : action
}

/**
 * Parse a param override audit line into action and content
 */
export function parseAuditLine(
  line: string
): { action: string; content: string } | null {
  if (typeof line !== 'string') return null
  const firstSpace = line.indexOf(' ')
  if (firstSpace <= 0) return { action: line, content: line }
  return {
    action: line.slice(0, firstSpace),
    content: line.slice(firstSpace + 1),
  }
}

/**
 * Check if the log is a violation fee log
 */
export function isViolationFeeLog(other: LogOtherData | null): boolean {
  if (!other) return false
  return (
    other.violation_fee === true ||
    Boolean(other.violation_fee_code) ||
    Boolean(other.violation_fee_marker)
  )
}

/**
 * Parse the 'other' field from JSON string to object
 */
export function parseLogOther(other: string): LogOtherData | null {
  if (!other) return null
  try {
    return JSON.parse(other) as LogOtherData
  } catch (error) {
    // eslint-disable-next-line no-console
    console.error('Failed to parse log other field:', error)
    return null
  }
}

/**
 * Get time color based on duration (in seconds)
 */
export function getTimeColor(
  seconds: number
): 'success' | 'warning' | 'danger' {
  if (seconds < 10) return 'success'
  if (seconds < 30) return 'warning'
  return 'danger'
}

/**
 * Get first-response-token color based on latency (in seconds)
 */
export function getFirstResponseTimeColor(
  seconds: number
): 'success' | 'warning' | 'danger' {
  if (seconds < 5) return 'success'
  if (seconds < 10) return 'warning'
  return 'danger'
}

/**
 * Get throughput color based on generated tokens per second
 */
export function getThroughputColor(
  tokensPerSecond: number
): 'success' | 'warning' | 'danger' {
  if (tokensPerSecond >= 30) return 'success'
  if (tokensPerSecond >= 15) return 'warning'
  return 'danger'
}

/**
 * Get response color using throughput only when enough output tokens exist.
 */
export function getResponseTimeColor(
  seconds: number,
  completionTokens: number
): 'success' | 'warning' | 'danger' {
  if (completionTokens < 100 || seconds <= 0) return getTimeColor(seconds)
  return getThroughputColor(completionTokens / seconds)
}

/**
 * Format model name with mapping indicator
 */
export function formatModelName(log: UsageLog): {
  name: string
  isMapped: boolean
  actualModel?: string
} {
  const other = parseLogOther(log.other)
  const isMapped = !!(
    other?.is_model_mapped &&
    other?.upstream_model_name &&
    other.upstream_model_name !== ''
  )

  return {
    name: log.model_name,
    isMapped,
    actualModel: isMapped ? other.upstream_model_name : undefined,
  }
}

/**
 * Decode a base64-encoded billing expression. Safely returns an empty string
 * when the input is missing or malformed (e.g. legacy logs without expr_b64).
 */
export function decodeBillingExprB64(exprB64: string | undefined): string {
  if (!exprB64) return ''
  try {
    return atob(exprB64)
  } catch {
    return ''
  }
}

/**
 * Resolve which parsed tier corresponds to the matched_tier label in a log
 * entry. Falls back to the first tier when the label is missing or unknown,
 * which mirrors the behaviour of the classic frontend renderer.
 */
export function resolveMatchedTier(
  tiers: ParsedTier[],
  matchedLabel: string | undefined
): ParsedTier | null {
  if (tiers.length === 0) return null
  if (matchedLabel) {
    const found = tiers.find((tier) => tier.label === matchedLabel)
    if (found) return found
  }
  return tiers[0]
}

/**
 * Tiered pricing summary derived from an `other` log payload using the
 * billing-expression library. Returns null when the entry is not a tiered
 * billing log or the expression failed to parse.
 */
export interface TieredBillingSummary {
  tiers: ParsedTier[]
  tier: ParsedTier
  priceEntries: Array<{ field: string; shortLabel: string; price: number }>
}

/**
 * Whether the request payload reports any cache-related token usage. Used to
 * suppress cache pricing rows from the tiered breakdown when the request did
 * not exercise the cache path (mirrors the classic frontend behaviour).
 */
export function hasAnyCacheTokens(
  other: LogOtherData | null | undefined
): boolean {
  if (!other) return false
  return (
    (other.cache_tokens || 0) > 0 ||
    (other.cache_creation_tokens || 0) > 0 ||
    (other.cache_creation_tokens_5m || 0) > 0 ||
    (other.cache_creation_tokens_1h || 0) > 0
  )
}

export function getTieredBillingSummary(
  other: LogOtherData | null
): TieredBillingSummary | null {
  if (!other || other.billing_mode !== 'tiered_expr') return null
  const exprStr = decodeBillingExprB64(other.expr_b64)
  if (!exprStr) return null
  const tiers = parseTiersFromExpr(exprStr)
  const tier = resolveMatchedTier(tiers, other.matched_tier)
  if (!tier) return null

  const cacheTokensPresent = hasAnyCacheTokens(other)

  const priceEntries: TieredBillingSummary['priceEntries'] = []
  for (const v of BILLING_PRICING_VARS) {
    if (!v.field) continue
    if (v.group === 'cache' && !cacheTokensPresent) continue
    const raw = tier[v.field as keyof ParsedTier]
    const price = Number(raw)
    if (Number.isFinite(price) && price > 0) {
      priceEntries.push({
        field: v.field,
        shortLabel: v.shortLabel,
        price,
      })
    }
  }
  return { tiers, tier, priceEntries }
}

/**
 * Calculate duration and return formatted result with color variant
 * @param submitTime - Submit timestamp
 * @param finishTime - Finish timestamp
 * @param unit - Unit of the timestamps ('seconds' or 'milliseconds')
 */
export function formatDuration(
  submitTime?: number,
  finishTime?: number,
  unit: 'seconds' | 'milliseconds' = 'milliseconds'
): { durationSec: number; variant: StatusBadgeProps['variant'] } | null {
  if (!submitTime || !finishTime) return null

  const durationSec =
    unit === 'milliseconds'
      ? (finishTime - submitTime) / 1000
      : finishTime - submitTime

  return { durationSec, variant: durationSec > 60 ? 'red' : 'green' }
}
