import { t, type MessageKey } from '@/shared/i18n'
import type { ChangedFile, MergeMethod, PullState, ReviewState, ReviewerState, UserDto } from '@/entities/pull-request'
import type { DiffFile, DiffFileStatus } from '@/entities/repo'

/** UI-only filter: the backend understands open/closed/merged and no filter. */
export type PullFilter = PullState | 'all' | 'draft'

const PULL_STATE_KEYS: Record<PullState, MessageKey> = {
  open: 'pull.state.open',
  closed: 'pull.state.closed',
  merged: 'pull.state.merged',
}

/** Lazy so badges follow the active locale. */
export const PULL_STATE_LABEL = new Proxy({} as Record<PullState, string>, {
  get: (_target, key: PullState) => t(PULL_STATE_KEYS[key]),
})

/** tailwind-ish tone classes shared across badges (mirrors repo-history colors). */
export const TONE = {
  green: 'text-[#1a7f37] bg-[rgba(35,165,90,0.12)]',
  red: 'text-[#b42318] bg-[rgba(242,63,67,0.10)]',
  amber: 'text-[#8a6100] bg-[rgba(240,178,50,0.16)]',
  violet: 'text-[#6937c3] bg-[rgba(120,82,196,0.12)]',
  gray: 'text-shell-ink-muted bg-shell-active',
} as const

const REVIEW_STATE_KEYS: Record<ReviewState, MessageKey> = {
  approved: 'pull.reviewState.approved',
  changes_requested: 'pull.reviewState.changesRequested',
  commented: 'pull.reviewState.commented',
  pending: 'pull.reviewState.pending',
  dismissed: 'pull.reviewState.dismissed',
}

export const REVIEW_STATE_LABEL = new Proxy({} as Record<ReviewState, string>, {
  get: (_target, key: ReviewState) => t(REVIEW_STATE_KEYS[key]),
})

export const REVIEW_STATE_TONE: Record<ReviewState, keyof typeof TONE> = {
  approved: 'green',
  changes_requested: 'red',
  commented: 'gray',
  pending: 'amber',
  dismissed: 'gray',
}

const REVIEWER_STATE_KEYS: Record<ReviewerState, MessageKey> = {
  requested: 'pull.reviewerState.requested',
  approved: 'pull.reviewerState.approved',
  changes_requested: 'pull.reviewerState.changesRequested',
  commented: 'pull.reviewerState.commented',
  dismissed: 'pull.reviewerState.dismissed',
}

export const REVIEWER_STATE_LABEL = new Proxy({} as Record<ReviewerState, string>, {
  get: (_target, key: ReviewerState) => t(REVIEWER_STATE_KEYS[key]),
})

const MERGE_METHOD_KEYS: Record<MergeMethod, MessageKey> = {
  merge: 'pull.mergeMethod.merge',
  squash: 'pull.mergeMethod.squash',
  rebase: 'pull.mergeMethod.rebase',
}

export const MERGE_METHOD_LABEL = new Proxy({} as Record<MergeMethod, string>, {
  get: (_target, key: MergeMethod) => t(MERGE_METHOD_KEYS[key]),
})

/** The backend formats status with `{:?}` (Debug names) — normalize loosely. */
export function normalizeFileStatus(raw: string): DiffFileStatus {
  const s = raw.toLowerCase()
  if (s.startsWith('ad') || s.startsWith('new') || s.startsWith('creat') || s === 'a') return 'added'
  if (s.startsWith('del') || s.startsWith('rem') || s === 'd') return 'deleted'
  if (s.startsWith('ren') || s.startsWith('mov') || s === 'r') return 'renamed'
  if (s.startsWith('cop') || s === 'c') return 'copied'
  if (s.startsWith('bin')) return 'binary'
  return 'modified'
}

const EVENT_KEYS: Record<string, MessageKey> = {
  created: 'pull.event.created',
  updated: 'pull.event.updated',
  title_changed: 'pull.event.titleChanged',
  body_edited: 'pull.event.bodyEdited',
  base_changed: 'pull.event.baseChanged',
  marked_ready: 'pull.event.markedReady',
  marked_draft: 'pull.event.markedDraft',
  closed: 'pull.event.closed',
  reopened: 'pull.event.reopened',
  merged: 'pull.event.merged',
  review_requested: 'pull.event.reviewRequested',
  review_request_removed: 'pull.event.reviewRequestRemoved',
  review_submitted: 'pull.event.reviewSubmitted',
  approved: 'pull.event.approved',
  changes_requested: 'pull.event.changesRequested',
  comment: 'pull.event.comment',
  labeled: 'pull.event.labeled',
  unlabeled: 'pull.event.unlabeled',
  assigned: 'pull.event.assigned',
  unassigned: 'pull.event.unassigned',
  locked: 'pull.event.locked',
  unlocked: 'pull.event.unlocked',
  force_push: 'pull.event.forcePush',
  branch_updated: 'pull.event.branchUpdated',
  head_ref_updated: 'pull.event.headRefUpdated',
  auto_merge_enabled: 'pull.event.autoMergeEnabled',
  auto_merge_disabled: 'pull.event.autoMergeDisabled',
}

/** Unknown backend event types keep rendering as their raw snake_case name. */
export const eventLabel = (eventType: string): string =>
  EVENT_KEYS[eventType] ? t(EVENT_KEYS[eventType]) : eventType.replaceAll('_', ' ')

export const userName = (user?: UserDto | null): string =>
  user?.display_name || user?.username || t('common.state.unknownUser')

export interface InlineAnchor {
  path: string
  line: number
  side: 'left' | 'right'
}

export const anchorKey = (path: string, line: number, side: 'left' | 'right') => `${path}#${side}${line}`

/** A pinned inline comment as rendered under its diff line. */
export interface AnchoredComment {
  id: string
  body: string
}

export function changedFileToDiff(file: ChangedFile): DiffFile {
  const status = file.binary ? 'binary' : normalizeFileStatus(file.path.status)
  return {
    path: file.path.new_path,
    oldPath: file.path.old_path && file.path.old_path !== file.path.new_path ? file.path.old_path : null,
    status,
    raw: file.patch ?? '',
    additions: file.lines_added,
    deletions: file.lines_removed,
  }
}