/**
 * @file WorkspaceRow — one workspace (lane) in the sidebar's workspace list, one
 * line like a Claude Desktop project: a chevron that expands its sessions, the
 * status dot, the name (click opens the workspace, double-click renames,
 * `PATCH /api/lanes/:id {title}`) and on hover `+` (a new
 * session there) and `⋯` (the row menu, `WorkspaceRowMenu.tsx`, also on
 * right-click). Dragging it, or Alt+↑/↓, reorders the list — a viewer
 * preference kept in localStorage (`laneOrderStorage.ts`), never written to
 * the lane row. The row only STARTS a drag (`LANE_DRAG_TYPE`); the list
 * (`WorkspaceTree.tsx`) takes the drop anywhere, gaps included. F2 renames too; the
 * dot's meaning is screen-reader text, and an idle dot is a ring. A `readOnly`
 * row (another user's workspace, for an analyst) has no menu, rename or `+`.
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

import { useState, type MouseEvent } from "react";
import { useTranslation } from "react-i18next";
import { ChevronDown, ChevronRight, Eye, MoreHorizontal, Plus } from "lucide-react";
import type { Lane } from "../../lib/types";
import { isSubmitEnter } from "../../lib/keys";

/** What a workspace row's drag carries: its index in the list. */
export const LANE_DRAG_TYPE = "application/x-agenthub-lane";
export const isLaneDrag = (e: { dataTransfer: DataTransfer | null }) =>
  !!e.dataTransfer?.types?.includes(LANE_DRAG_TYPE);

/** The row's dot: the lane's liveness, plus a running pulse and needs-you. */
export function workspaceDot(lane: Lane): string {
  if (lane.needs_action) return "bg-status-warning";
  if (lane.liveness === "dead" || lane.status === "error") return "bg-status-danger";
  if (lane.status === "running") return "bg-status-success animate-pulse-slow";
  if (lane.liveness === "active") return "bg-status-success";
  // A ring, not a fill: an idle surface-4 dot vanished on the light themes.
  return "border border-fg-muted";
}

/** What the dot means (`row.state.*`), for a screen reader. */
export function workspaceDotLabel(lane: Lane): string {
  if (lane.needs_action) return "needsYou";
  if (lane.liveness === "dead" || lane.status === "error") return "error";
  if (lane.status === "running") return "running";
  if (lane.liveness === "active") return "active";
  return "idle";
}

export function workspaceName(lane: Lane): string {
  return lane.title || lane.cwd.split("/").filter(Boolean).pop() || lane.cwd;
}

export function WorkspaceRow({
  lane,
  index,
  readOnly,
  selected,
  expanded,
  renaming,
  onSelect,
  onToggle,
  onNewSession,
  onReorder,
  onMenu,
  onRenameStart,
  onRenameEnd,
}: {
  lane: Lane;
  /** Position in the list — the unit both reorder paths speak in. */
  index: number;
  /** Set (to its tooltip) for a workspace this user may only read: no menu,
   *  no rename, no new session. */
  readOnly?: string;
  selected: boolean;
  expanded: boolean;
  renaming: boolean;
  onSelect: () => void;
  onToggle: () => void;
  onNewSession: () => void;
  onReorder: (from: number, to: number) => void;
  /** Open the row menu at a viewport point. */
  onMenu: (x: number, y: number) => void;
  onRenameStart: () => void;
  /** Called with the new title on Enter, or null when the edit was cancelled. */
  onRenameEnd: (title: string | null) => void;
}) {
  const { t } = useTranslation("lanes");
  const [draft, setDraft] = useState("");
  const name = workspaceName(lane);
  const openMenu = (e: MouseEvent) => {
    e.preventDefault();
    e.stopPropagation();
    if (!readOnly) onMenu(e.clientX, e.clientY);
  };
  const startRename = () => {
    if (readOnly) return;
    setDraft(lane.title || "");
    onRenameStart();
  };
  const Chevron = expanded ? ChevronDown : ChevronRight;
  const hoverBtn =
    "shrink-0 rounded p-0.5 text-fg-muted opacity-0 transition-opacity hover:bg-surface-4 hover:text-fg-primary focus:opacity-100 group-hover:opacity-100";

  return (
    <div
      data-testid={`workspace-row-${lane.id}`}
      data-lane-index={index}
      draggable={!renaming}
      onDragStart={(e) => {
        // Firefox starts no drag at all without a setData call.
        e.dataTransfer.setData(LANE_DRAG_TYPE, String(index));
        e.dataTransfer.effectAllowed = "move";
      }}
      onContextMenu={openMenu}
      className={`group flex items-center gap-1 rounded-md pl-1 pr-1 transition-colors ${
        selected
          ? "bg-accent/10"
          : lane.needs_action
            ? "bg-status-warning/10 hover:bg-status-warning/20"
            : "hover:bg-surface-3"
      }`}
    >
      <button
        type="button"
        data-testid={`workspace-toggle-${lane.id}`}
        aria-expanded={expanded}
        aria-label={name}
        onClick={onToggle}
        className="shrink-0 rounded p-0.5 text-fg-muted hover:text-fg-primary"
      >
        <Chevron className="h-3.5 w-3.5" />
      </button>
      {renaming ? (
        <input
          data-testid={`workspace-rename-${lane.id}`}
          aria-label={t("renameLabel")}
          autoFocus
          value={draft}
          maxLength={200}
          onChange={(e) => setDraft(e.target.value)}
          // Blur CANCELS — Enter is the only save, so one edit fires one PATCH.
          onBlur={() => onRenameEnd(null)}
          onKeyDown={(e) => {
            if (isSubmitEnter(e)) onRenameEnd(draft.trim());
            if (e.key === "Escape") onRenameEnd(null);
          }}
          className="my-1 min-w-0 flex-1 rounded border border-accent bg-surface-1 px-1.5 py-0.5 text-[13px] text-fg-primary"
        />
      ) : (
        <button
          type="button"
          data-testid={`workspace-open-${lane.id}`}
          aria-current={selected ? "true" : undefined}
          // A double-click's second click renames instead of opening again.
          onClick={(e) => e.detail < 2 && onSelect()}
          onDoubleClick={startRename}
          onKeyDown={(e) => {
            if (e.key === "F2") {
              e.preventDefault();
              startRename();
              return;
            }
            if (!e.altKey || (e.key !== "ArrowUp" && e.key !== "ArrowDown")) return;
            e.preventDefault();
            onReorder(index, index + (e.key === "ArrowUp" ? -1 : 1));
          }}
          title={`${lane.cwd}\n${readOnly ?? t("row.hint")}`}
          className="flex min-w-0 flex-1 items-center gap-2 py-1.5 text-left"
        >
          <span aria-hidden className={`h-2 w-2 shrink-0 rounded-full ${workspaceDot(lane)}`} />
          <span className="sr-only">{t(`row.state.${workspaceDotLabel(lane)}`)}</span>
          <span className="truncate text-[13px] font-medium text-fg-primary">{name}</span>
        </button>
      )}
      {readOnly && <Eye aria-label={readOnly} className="mr-1 h-3 w-3 shrink-0 text-fg-muted" />}
      {!renaming && !readOnly && (
        <>
          <button
            type="button"
            data-testid={`workspace-new-${lane.id}`}
            aria-label={t("tree.newSession")}
            title={t("tree.newSession")}
            onClick={onNewSession}
            className={hoverBtn}
          >
            <Plus className="h-3.5 w-3.5" />
          </button>
          <button
            type="button"
            data-testid={`workspace-menu-${lane.id}`}
            aria-label={t("row.actions")}
            title={t("row.actions")}
            onClick={openMenu}
            className={hoverBtn}
          >
            <MoreHorizontal className="h-3.5 w-3.5" />
          </button>
        </>
      )}
    </div>
  );
}