import type { Thread } from "../types";
import { cn } from "../lib/utils";
import { findLatestProposedPlan, isLatestTurnSettled } from "../session-logic";

export const THREAD_SELECTION_SAFE_SELECTOR = "[data-thread-item], [data-thread-selection-safe]";
export type SidebarNewThreadEnvMode = "local" | "worktree";

export interface ThreadStatusPill {
  label:
    | "Working"
    | "Connecting"
    | "Completed"
    | "Pending Approval"
    | "Awaiting Input"
    | "Plan Ready";
  colorClass: string;
  dotClass: string;
  pulse: boolean;
}

type ThreadStatusInput = Pick<
  Thread,
  "interactionMode" | "latestTurn" | "lastVisitedAt" | "proposedPlans" | "session"
>;

export function hasUnseenCompletion(thread: ThreadStatusInput): boolean {
  if (!thread.latestTurn?.completedAt) return false;
  const completedAt = Date.parse(thread.latestTurn.completedAt);
  if (Number.isNaN(completedAt)) return false;
  if (!thread.lastVisitedAt) return true;

  const lastVisitedAt = Date.parse(thread.lastVisitedAt);
  if (Number.isNaN(lastVisitedAt)) return true;
  return completedAt > lastVisitedAt;
}

export function shouldClearThreadSelectionOnMouseDown(target: HTMLElement | null): boolean {
  if (target === null) return true;
  return !target.closest(THREAD_SELECTION_SAFE_SELECTOR);
}

export function resolveSidebarNewThreadEnvMode(input: {
  requestedEnvMode?: SidebarNewThreadEnvMode;
  defaultEnvMode: SidebarNewThreadEnvMode;
}): SidebarNewThreadEnvMode {
  return input.requestedEnvMode ?? input.defaultEnvMode;
}

export function resolveThreadRowClassName(input: {
  isActive: boolean;
  isSelected: boolean;
}): string {
  const baseClassName =
    "h-7 w-full translate-x-0 cursor-default justify-start px-2 text-left select-none focus-visible:ring-0";

  if (input.isSelected && input.isActive) {
    return cn(
      baseClassName,
      "bg-primary/22 text-foreground font-medium hover:bg-primary/26 hover:text-foreground dark:bg-primary/30 dark:hover:bg-primary/36",
    );
  }

  if (input.isSelected) {
    return cn(
      baseClassName,
      "bg-primary/15 text-foreground hover:bg-primary/19 hover:text-foreground dark:bg-primary/22 dark:hover:bg-primary/28",
    );
  }

  if (input.isActive) {
    return cn(
      baseClassName,
      "bg-accent/85 text-foreground font-medium hover:bg-accent hover:text-foreground dark:bg-accent/55 dark:hover:bg-accent/70",
    );
  }

  return cn(baseClassName, "text-muted-foreground hover:bg-accent hover:text-foreground");
}

export function resolveThreadStatusPill(input: {
  thread: ThreadStatusInput;
  hasPendingApprovals: boolean;
  hasPendingUserInput: boolean;
}): ThreadStatusPill | null {
  const { hasPendingApprovals, hasPendingUserInput, thread } = input;

  if (hasPendingApprovals) {
    return {
      label: "Pending Approval",
      colorClass: "text-amber-600 dark:text-amber-300/90",
      dotClass: "bg-amber-500 dark:bg-amber-300/90",
      pulse: false,
    };
  }

  if (hasPendingUserInput) {
    return {
      label: "Awaiting Input",
      colorClass: "text-indigo-600 dark:text-indigo-300/90",
      dotClass: "bg-indigo-500 dark:bg-indigo-300/90",
      pulse: false,
    };
  }

  if (thread.session?.status === "running") {
    return {
      label: "Working",
      colorClass: "text-sky-600 dark:text-sky-300/80",
      dotClass: "bg-sky-500 dark:bg-sky-300/80",
      pulse: true,
    };
  }

  if (thread.session?.status === "connecting") {
    return {
      label: "Connecting",
      colorClass: "text-sky-600 dark:text-sky-300/80",
      dotClass: "bg-sky-500 dark:bg-sky-300/80",
      pulse: true,
    };
  }

  const hasPlanReadyPrompt =
    !hasPendingUserInput &&
    thread.interactionMode === "plan" &&
    isLatestTurnSettled(thread.latestTurn, thread.session) &&
    findLatestProposedPlan(thread.proposedPlans, thread.latestTurn?.turnId ?? null) !== null;
  if (hasPlanReadyPrompt) {
    return {
      label: "Plan Ready",
      colorClass: "text-violet-600 dark:text-violet-300/90",
      dotClass: "bg-violet-500 dark:bg-violet-300/90",
      pulse: false,
    };
  }

  if (hasUnseenCompletion(thread)) {
    return {
      label: "Completed",
      colorClass: "text-emerald-600 dark:text-emerald-300/90",
      dotClass: "bg-emerald-500 dark:bg-emerald-300/90",
      pulse: false,
    };
  }

  return null;
}