/**
 * The two-segment node card of the Tasks graph: a TOP segment that says WHAT
 * the node is (kind badge, name, mono meta, optional task line) and a BOTTOM
 * bar that says WHAT IT IS DOING (state dot + state word + the merged process
 * activity, plus the fold chevron once the node has settled).
 *
 * Both modes share the model but NOT the card: the TREE keeps its compact
 * indent row (its own disclosure, its own keyboard recipe), so this module is
 * graph-only. Its two pieces are separate components because every node kind
 * (agent / workflow run / fold aggregate) composes them differently while the
 * geometry stays identical — the layout reserves the height of exactly these
 * rows (`tasks-graph-layout.ts`).
 *
 * Colour: the group colour of a node is its tree DEPTH, from the plugin's own
 * token-only ramp (`.depth0…3` in tasks-graph.module.css). The host ships no
 * chart palette and the skin contract forbids literal colours, so the ramp is
 * mixed from `--dsw-alias-state-business-primary`; a workflow member's PHASE
 * badge uses the ink family instead, so the two groupings never share a hue.
 */
import type { ReactNode } from 'react'
import clsx from 'clsx'
import { IconChevronUpOutlineRegular, StateDot } from '@deepseek-ai/dsh-client-ui-primitives'
import type { TasksNodeState } from './tasks-model.ts'
import { nodeDotState, stateLabel } from './tasks-shared.tsx'
import { t } from './locales.ts'
import css from './tasks-graph.module.css'

/** The five kinds of card the graph draws. */
export type CardKind = 'main' | 'subagent' | 'teammate' | 'workflow' | 'fold'

/**
 * The kind badge's word: the SAME vocabulary the rest of the page uses (the
 * header already calls the root "主代理"), so no sixth word is invented for it.
 *
 * The aggregate's badge says 已完成 only when something WAS completed: an
 * aggregate that sweeps idle teammates (or only failed rows) and still claimed
 * "✓ N 已完成" would be lying about what is inside it, so `foldBadgeIdle`
 * switches it to the idle word for exactly that case.
 * @param kind - card kind.
 * @param count - folded member count (the fold aggregate's badge only).
 * @param foldBadgeIdle - the aggregate holds no completed row (see above).
 */
export function cardKindLabel(kind: CardKind, count = 0, foldBadgeIdle = false): string {
  switch (kind) {
    case 'main': return t('subagentMainAgent')
    case 'subagent': return t('tasksKindSubagent')
    case 'teammate': return t('tasksKindTeammate')
    case 'workflow': return t('tasksKindWorkflow')
    case 'fold': return foldBadgeIdle
      ? t('tasksFoldIdle', { count })
      : t('tasksFoldCompleted', { count })
  }
}

/**
 * The depth class of a node's group colour (levels past 3 share the last one).
 * Typed `string | undefined` because the CSS-module map is an open record: a
 * typo'd class name would otherwise pass `tsc` as a `string`.
 */
export function depthClass(depth: number): string | undefined {
  if (depth <= 0) return css.depth0
  if (depth === 1) return css.depth1
  if (depth === 2) return css.depth2
  return css.depth3
}

/** The phase class of a workflow member's badge (phases past 3 share the last one). */
export function phaseClass(index: number): string | undefined {
  if (index <= 0) return css.phase0
  if (index === 1) return css.phase1
  if (index === 2) return css.phase2
  return css.phase3
}

/** The top segment: the node's identity. */
export function CardTop(props: {
  kind: CardKind
  /** Folded member count, for the aggregate's badge. */
  count?: number
  /** Whether the aggregate holds no completed row (its badge switches word). */
  badgeIdle?: boolean
  /** Tree depth → the group colour of the badge and the card's left edge. */
  depth: number
  /** Workflow phase (a member's badge). */
  phase?: { index: number; title?: string }
  /** The node's name (already resolved by the model). */
  name: string
  /** The mono meta line under the name. */
  meta?: string
  /** Extra class for the name (the aggregate recedes one rung). */
  extraClass?: string
  /** Extra rows the caller appends (the team task line). */
  children?: ReactNode
}): ReactNode {
  const { kind, count, badgeIdle, depth, phase } = props
  return (
    <span className={clsx(css.cardTop, depthClass(depth))}>
      <span className={css.cardBadges}>
        <span className={css.kindBadge} data-card-kind={kind}>
          {cardKindLabel(kind, count ?? 0, badgeIdle === true)}
        </span>
        {phase !== undefined && (
          <span
            className={clsx(css.phaseBadge, phaseClass(phase.index))}
            title={phase.title ?? t('workflowPhaseUnnamed')}
          >
            {phase.title ?? t('workflowPhaseUnnamed')}
          </span>
        )}
      </span>
      <span className={clsx(css.cardName, props.extraClass)} title={props.name}>{props.name}</span>
      {props.meta !== undefined && props.meta !== '' && (
        <span className={css.cardMeta} title={props.meta}>{props.meta}</span>
      )}
      {props.children}
    </span>
  )
}

/** The bottom bar: the node's state, its merged activity, and its fold chevron. */
export function CardBar(props: {
  state: TasksNodeState
  /** The merged process activity line (running nodes and settled summaries). */
  activity?: string
  /** Whether the node is executing (drives the sweep). */
  running?: boolean
  /** Fold the node into its parent's completed aggregate (settled nodes only). */
  onFold?: (event: { stopPropagation(): void }) => void
  /** The chevron's accessible name (defaults to the per-node fold word). */
  foldLabel?: string
  /** Render the state WORD next to the dot (off for the aggregate's action bar). */
  stateWord?: boolean
  /** Replace the whole bar's content (the aggregate's action row). */
  children?: ReactNode
}): ReactNode {
  const { state, activity, running } = props
  return (
    <span
      className={css.cardBar}
      data-card-bar={state}
      data-running={running === true ? 'true' : undefined}
    >
      {props.children ?? (
        <>
          <StateDot state={nodeDotState(state)} size={6} className={css.barDot} />
          {props.stateWord !== false && <span className={css.barState}>{stateLabel(state)}</span>}
          {activity !== undefined && activity !== '' && (
            <span className={css.barActivity} title={activity}>{activity}</span>
          )}
          {props.onFold !== undefined && (
            <button
              type="button"
              className={css.barFold}
              aria-label={props.foldLabel ?? t('tasksFoldOne')}
              title={props.foldLabel ?? t('tasksFoldOne')}
              onClick={(event) => {
                // The card's own click opens the detail popover: folding must
                // never do both.
                event.stopPropagation()
                props.onFold?.(event)
              }}
            >
              {/*
                The COLLAPSE direction (chevron up = gather into the group): the
                aggregate card at the other end of the same motion offers the
                EXPAND one (chevron down). Two opposite actions must not share
                a glyph — the first cut drew both as a down chevron.
              */}
              <IconChevronUpOutlineRegular size={12} />
            </button>
          )}
        </>
      )}
    </span>
  )
}