/**
 * @file Sagi.tsx
 * @description Floating mascot companion shell. Mounted once by `SagiMount` (next
 *   to UpdateNotifier in Layout), which loads this chunk only while the mascot is
 *   enabled; `Sagi` gates on the same preference itself, and the body (brain,
 *   tick, WS reducer) runs only while it is on. Persists across routes and
 *   shares the single WebSocket.
 *   Owns the open/closed panel state, the ⌘B / Esc shortcuts, reduced-motion
 *   detection, and route navigation. Reactive personality + status/Ask come
 *   from useSagiBrain; the avatar is draggable (AssistiveTouch-style) via
 *   useSagiPosition (a v2 Codex pet also looks toward the pointer), and the
 *   bubble/panel render in a self-clamping flyout so
 *   they never spill off any screen edge regardless of where the mascot is docked.
 *
 *   The "do the job" path: an unmatched Ask query starts a claude session in
 *   the "Sagi" workspace carrying it as the first prompt, then opens that
 *   workspace's session view (`/workspace?lane=<id>&run=<runId>`) — no new LLM
 *   backend. ⌘B/Ctrl+B is taken only while the mascot is shown and focus is not
 *   in an editable field (a terminal's Ctrl+B is tmux's prefix).
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */
/* =============================================================================
 * MODULE_GUIDE — extended in-file reference (comments only; safe to read, never executed)
 * =============================================================================
 * **Purpose:** Sagi is the optional on-screen mascot assistant — quips, intents, and lightweight event reactions layered above the dashboard chrome.
 *
 * ## Design constraints
 * - Local-first: no telemetry leaves the machine unless the user configures webhooks.
 * - Fail-safe hooks path on the server must never block Claude Code; UI mirrors that
 *   philosophy by degrading gracefully (empty states, stale badges, reconnect loops).
 * - Destructive flows stay behind explicit confirmation modals and server-side gates.
 * - Internationalization: user-visible strings belong in i18n JSON, not literals here.
 *
 * ## Remote data & SSH
 * Remote Data Sources let operators aggregate multiple machines. SSH entries describe
 * how to reach a peer dashboard; the global data scope (`dataScope.ts`) narrows every
 * scoped GET via `?sources=`. Health checks and import history surface in Settings.
 *
 * ## Internal dependencies
 * - `./SagiAvatar`
 * - `./SpeechBubble`
 * - `./SagiPanel`
 * - `./useSagiBrain`
 * - `./useSagiPosition`
 * - `./intents`
 * - `./prefs`
 *
 * ## Public surface
 * - `Sagi` — exported API; see TSDoc on the symbol for behavior.
 *
 * ## Testing pointers
 * - Prefer colocated `__tests__` with Vitest + Testing Library for UI.
 * - Server contract changes require `npm run test:server` and OpenAPI sync.
 *
 * ## Related docs
 * - `ARCHITECTURE.md` — hooks → API → SQLite → WebSocket → UI pipeline.
 * - `docs/API.md` — REST reference.
 * - `skills/file-headers/` — mandatory `@author` header policy.
 * ============================================================================= */
/* -----------------------------------------------------------------------------
 * EXPORT CATALOG — quick index of symbols defined below (documentation only).
 * -----------------------------------------------------------------------------
 * **Sagi**
 *   Part of this module's public contract. Downstream imports should treat
 *   the signature and return type as stable unless release notes say otherwise.
 *   When behavior changes, update the `@file` overview and relevant tests.
 *
 * ----------------------------------------------------------------------------- */

import {
  useCallback,
  useEffect,
  useLayoutEffect,
  useRef,
  useState,
  type CSSProperties,
  type ReactNode,
} from "react";
import { useNavigate } from "react-router-dom";
import { useSettingsHref } from "../../lib/settingsLink";
import { useTranslation } from "react-i18next";
import { SagiAvatar } from "./SagiAvatar";
import { PetSprite } from "./PetSprite";
import { PetMenu } from "./PetMenu";
import { SpeechBubble } from "./SpeechBubble";
import { SagiPanel } from "./SagiPanel";
import { useSagiBrain } from "./useSagiBrain";
import { useSagiPosition } from "./useSagiPosition";
import { useSagiEnabled } from "./SagiMount";
import { matchIntent } from "./intents";
import { petName, sagiPrefs } from "./prefs";
import type { SagiSubject } from "./brain";
import { api } from "../../lib/api";
import { readDefaultTool } from "../../lib/sessionDefaults";
import { startInFreeTabDetailed } from "../lanes/startSession";
import { workspaceHref } from "../SessionRowMenu";
import { PetChat, petChatTool } from "./PetChat";

// Stroking: this many left/right turns of the pointer over the pet, within
// STROKE_MS and with no button held, is a pat; then a pause before the next.
const STROKE_TURNS = 4;
const STROKE_MS = 1200;
const STROKE_COOLDOWN_MS = 1500;
import "./sagi.css";

const FLYOUT_GAP = 10; // px between avatar and flyout
const VIEWPORT_MARGIN = 12; // min gap from any screen edge

/** True while focus sits where typing happens (an input, a terminal's textarea). */
function isEditable(el: EventTarget | null): boolean {
  if (!(el instanceof HTMLElement)) return false;
  return (
    el.isContentEditable ||
    el.tagName === "INPUT" ||
    el.tagName === "TEXTAREA" ||
    el.tagName === "SELECT"
  );
}

interface Anchor {
  left: number;
  top: number;
  size: number;
  side: "left" | "right";
  openUp: boolean;
  dragging: boolean;
}

/** The OS "reduce motion" preference, followed live. */
export function usePrefersReducedMotion(): boolean {
  const [reduced, setReduced] = useState(
    () =>
      typeof window !== "undefined" &&
      window.matchMedia?.("(prefers-reduced-motion: reduce)").matches
  );
  useEffect(() => {
    const mq = window.matchMedia?.("(prefers-reduced-motion: reduce)");
    if (!mq) return;
    const onChange = () => setReduced(mq.matches);
    mq.addEventListener?.("change", onChange);
    return () => mq.removeEventListener?.("change", onChange);
  }, []);
  return reduced;
}

/**
 * Fixed-position wrapper that places its content next to the avatar and clamps
 * it inside the viewport. It measures itself (and re-measures on content/size
 * changes via ResizeObserver) so a tall panel near a screen edge slides fully
 * into view instead of being cropped.
 */
/**
 * `front`: above the mascot itself — the pet menu, which may overlap it.
 * `beside`: at the mascot's side instead of above it — the chat window, on the
 * screen side away from the edge it docks to, its bottom level with the pet's.
 */
function SagiFlyout({
  anchor,
  children,
  front = false,
  beside = false,
}: {
  anchor: Anchor;
  children: ReactNode;
  front?: boolean;
  beside?: boolean;
}) {
  const ref = useRef<HTMLDivElement>(null);
  const [style, setStyle] = useState<CSSProperties>({ visibility: "hidden" });

  const place = useCallback(() => {
    const el = ref.current;
    if (!el) return;
    const w = el.offsetWidth;
    const h = el.offsetHeight;
    const vw = window.innerWidth;
    const vh = window.innerHeight;

    if (beside) {
      let left =
        anchor.side === "left"
          ? anchor.left + anchor.size + FLYOUT_GAP
          : anchor.left - w - FLYOUT_GAP;
      left = Math.min(vw - w - VIEWPORT_MARGIN, Math.max(VIEWPORT_MARGIN, left));
      let top = anchor.top + anchor.size - h;
      top = Math.min(vh - h - VIEWPORT_MARGIN, Math.max(VIEWPORT_MARGIN, top));
      setStyle({ left, top, visibility: "visible" });
      return;
    }

    // Horizontal: hug the avatar's docked edge, then clamp on-screen.
    let left = anchor.side === "left" ? anchor.left : anchor.left + anchor.size - w;
    left = Math.min(vw - w - VIEWPORT_MARGIN, Math.max(VIEWPORT_MARGIN, left));

    // Vertical: prefer above the mascot (feels natural). Only drop below when
    // there isn't room above - i.e. the mascot is near the top edge.
    const above = anchor.top - h - FLYOUT_GAP;
    const below = anchor.top + anchor.size + FLYOUT_GAP;
    let top = above >= VIEWPORT_MARGIN ? above : below;
    top = Math.min(vh - h - VIEWPORT_MARGIN, Math.max(VIEWPORT_MARGIN, top));

    setStyle({ left, top, visibility: "visible" });
  }, [anchor.left, anchor.top, anchor.size, anchor.side, anchor.openUp, beside]);

  useLayoutEffect(() => {
    place();
    const el = ref.current;
    if (!el || typeof ResizeObserver === "undefined") return;
    const ro = new ResizeObserver(() => place());
    ro.observe(el);
    window.addEventListener("resize", place);
    return () => {
      ro.disconnect();
      window.removeEventListener("resize", place);
    };
  }, [place]);

  return (
    <div
      ref={ref}
      className="sagi-flyout"
      // Mirrors the avatar button: eased left/top so the flyout glides along
      // with the mascot when it snaps to an edge, 1:1 (no easing) mid-drag.
      data-dragging={anchor.dragging ? "1" : "0"}
      data-front={front ? "1" : undefined}
      style={style}
    >
      {children}
    </div>
  );
}

/** Renders nothing — and runs no hook below — while the mascot is disabled. */
export function Sagi() {
  return useSagiEnabled() ? <SagiBody /> : null;
}

function SagiBody() {
  const { t } = useTranslation("settings");
  const [pet, setPet] = useState(() => sagiPrefs.getPet());
  // The name it goes by: the user's nickname, the pet's own, else Sagi.
  const [name, setName] = useState(() => petName(sagiPrefs.getPet()));
  const [size, setSize] = useState(() => sagiPrefs.getSize());
  const [open, setOpen] = useState(false);
  // The chat window (PetChat.tsx), and the Ask question it should send.
  const [chatOpen, setChatOpen] = useState(false);
  const [chatPrompt, setChatPrompt] = useState<string | null>(null);
  // The right-click pet menu (`PetMenu.tsx`).
  const [menu, setMenu] = useState(false);
  const [hover, setHover] = useState(false);
  const reducedMotion = usePrefersReducedMotion();
  const navigate = useNavigate();
  const href = useSettingsHref();
  const brain = useSagiBrain();
  const place = useSagiPosition(size);

  // Keep the pet and its size in sync with Settings / other tabs (enabled is
  // the `Sagi` gate's: it unmounts this body when the mascot is turned off).
  useEffect(
    () =>
      sagiPrefs.subscribe(() => {
        setPet(sagiPrefs.getPet());
        setName(petName(sagiPrefs.getPet()));
        setSize(sagiPrefs.getSize());
      }),
    []
  );

  // A pet worn before names rode along with the choice: look its name up once.
  const petId = pet.id;
  const unnamed = "kind" in pet && !pet.name;
  useEffect(() => {
    if (!unnamed) return;
    let live = true;
    api.pets
      .list()
      .then((list) => {
        const found = list.pets.find((p) => p.id === petId);
        const cur = sagiPrefs.getPet();
        if (live && found && cur.id === petId && "kind" in cur)
          sagiPrefs.setPet({ ...cur, name: found.displayName });
      })
      .catch(() => undefined);
    return () => {
      live = false;
    };
  }, [petId, unnamed]);

  // ⌘B / Ctrl+B toggles the panel; Esc closes it. Only while the mascot is
  // shown, and never from an editable field, where Ctrl+B belongs to the field.
  useEffect(() => {
    const onKey = (e: KeyboardEvent) => {
      if ((e.metaKey || e.ctrlKey) && e.key.toLowerCase() === "b") {
        if (isEditable(e.target) || isEditable(document.activeElement)) return;
        e.preventDefault();
        setOpen((v) => !v);
      } else if (e.key === "Escape") {
        setOpen(false);
        setChatOpen(false);
      }
    };
    window.addEventListener("keydown", onKey);
    return () => window.removeEventListener("keydown", onKey);
  }, []);

  // A v2 pet at idle looks toward the pointer: one of 16 poses by the
  // pointer's angle around it (0 = up, clockwise), dropped once it rests.
  // ponytail: rest after 2 s is a guess; Codex Desktop's own rule is not public.
  const btn = useRef<HTMLButtonElement>(null);
  const [gaze, setGaze] = useState<number | null>(null);
  const wearsSheet = "kind" in pet && pet.kind === "codex";
  useEffect(() => {
    if (!wearsSheet || reducedMotion) return;
    let rest = 0;
    const onMove = (e: PointerEvent) => {
      const r = btn.current?.getBoundingClientRect();
      if (!r) return;
      const deg =
        (Math.atan2(e.clientX - (r.left + r.width / 2), r.top + r.height / 2 - e.clientY) * 180) /
        Math.PI;
      setGaze(Math.round((deg + 360) / 22.5) % 16);
      window.clearTimeout(rest);
      rest = window.setTimeout(() => setGaze(null), 2000);
    };
    window.addEventListener("pointermove", onMove);
    return () => {
      window.removeEventListener("pointermove", onMove);
      window.clearTimeout(rest);
    };
  }, [wearsSheet, reducedMotion]);

  const onNavigate = useCallback(
    (route: string) => {
      navigate(route);
      setOpen(false);
    },
    [navigate]
  );

  // A session a bubble or the panel names: its live pane when a dashboard run
  // holds it, else its workspace's replay, else its analysis page. Opening
  // never resumes anything.
  const openSession = useCallback(
    (s: SagiSubject) => {
      const go = (runs?: Parameters<typeof workspaceHref>[1]) => {
        navigate(workspaceHref(s, runs) ?? `/sessions/${encodeURIComponent(s.id)}`);
        brain.dismissBubble();
        setOpen(false);
        setChatOpen(false);
      };
      api.run
        .list()
        .then((r) => go(r.items))
        .catch(() => go());
    },
    [brain, navigate]
  );

  const onAsk = useCallback(
    (query: string): string | null => {
      const result = matchIntent(query, brain.status, { name, attention: brain.attention });
      if (result.kind === "answer") {
        if (result.moment) brain.playMoment(result.moment);
        return result.text;
      }
      // Handoff: a question the pet cannot answer goes to the chat window,
      // which starts a session of the default AI tool and shows it as chat.
      if (petChatTool()) {
        setChatPrompt(result.prompt);
        setOpen(false);
        setChatOpen(true);
        return null;
      }
      // A default tool the chat cannot read back (not Claude/Codex): start it
      // in the "Sagi" workspace and open its pane there, as before.
      const prompt = result.prompt;
      brain.setThinking(true);
      (async () => {
        try {
          const { lane } = await api.lanes.ensure({ title: "Sagi" });
          const tool = readDefaultTool();
          const r = await startInFreeTabDetailed(lane.id, {
            prompt,
            ...(tool && tool !== lane.tool ? { tool } : {}),
          });
          navigate(`/workspace?lane=${r.laneId}&run=${encodeURIComponent(r.runId)}`);
          setOpen(false);
        } catch (err) {
          const msg = err instanceof Error ? err.message : String(err);
          brain.setBubble(t("sagi.startFailed", { error: msg }));
        } finally {
          brain.setThinking(false);
        }
      })();
      return null;
    },
    [brain, navigate, t, name]
  );

  // Stroke the pet (move the pointer back and forth over it) to pat it.
  const stroke = useRef({ dir: 0, x: 0, turns: [] as number[], until: 0 });
  const onStroke = (e: React.PointerEvent) => {
    if (e.buttons !== 0 || e.pointerType === "touch") return;
    const s = stroke.current;
    const now = performance.now();
    const dx = e.clientX - s.x;
    s.x = e.clientX;
    if (Math.abs(dx) < 2 || now < s.until) return;
    const dir = Math.sign(dx);
    if (s.dir && dir !== s.dir) {
      s.turns = [...s.turns.filter((t0) => now - t0 < STROKE_MS), now];
      if (s.turns.length >= STROKE_TURNS) {
        s.turns = [];
        s.until = now + STROKE_COOLDOWN_MS;
        brain.pat();
      }
    }
    s.dir = dir;
  };

  const onBusy = useCallback((b: boolean) => brain.setThinking(b), [brain.setThinking]);

  const anchor: Anchor = {
    left: place.left,
    top: place.top,
    size: place.size,
    side: place.side,
    openUp: place.openUp,
    dragging: place.dragging,
  };

  return (
    <>
      {/* The panel is too big to drag around, so it hides mid-drag. The bubble
          does not - it is Sagi talking, and it has to stay by its mouth. */}
      {!place.dragging && open && (
        <SagiFlyout anchor={anchor}>
          <SagiPanel
            name={name}
            ownName={"kind" in pet ? pet.name || "Sagi" : "Sagi"}
            nickname={sagiPrefs.getNickname(pet.id)}
            onRename={(next) => sagiPrefs.setNickname(pet.id, next)}
            onPat={brain.pat}
            attention={brain.attention}
            onOpenSession={openSession}
            status={brain.status}
            muted={brain.muted}
            onToggleMute={brain.toggleMute}
            onClearAlerts={brain.clearAlerts}
            onNavigate={onNavigate}
            onAsk={onAsk}
            onClose={() => setOpen(false)}
          />
        </SagiFlyout>
      )}

      {/* Beside the pet, riding along with it mid-drag too (SagiFlyout follows
          it 1:1), and kept mounted: unmounting would detach its terminal and
          lose a half-typed message. */}
      {chatOpen && (
        <SagiFlyout anchor={anchor} beside>
          <PetChat
            name={name}
            initialPrompt={chatPrompt}
            onPromptTaken={() => setChatPrompt(null)}
            onBack={() => {
              setChatOpen(false);
              setOpen(true);
            }}
            onClose={() => setChatOpen(false)}
            onOpenWorkspace={(laneId, runId) => {
              navigate(`/workspace?lane=${laneId}&run=${encodeURIComponent(runId)}`);
              setChatOpen(false);
            }}
            onBusy={onBusy}
          />
        </SagiFlyout>
      )}

      {!place.dragging && menu && (
        <SagiFlyout anchor={anchor} front>
          <PetMenu
            pet={pet}
            size={size}
            onClose={() => setMenu(false)}
            onSettings={() => {
              setMenu(false);
              navigate(href("appearance#pet"));
            }}
          />
        </SagiFlyout>
      )}

      {!open && !menu && !chatOpen && brain.bubble && (
        <SagiFlyout anchor={anchor}>
          <SpeechBubble
            bubble={brain.bubble}
            onDismiss={brain.dismissBubble}
            onOpen={openSession}
          />
        </SagiFlyout>
      )}

      <button
        ref={btn}
        className="sagi-avatar-btn"
        data-dragging={place.dragging ? "1" : "0"}
        style={{ left: place.left, top: place.top, width: size, height: size }}
        onPointerEnter={() => setHover(true)}
        onPointerLeave={() => setHover(false)}
        onPointerDown={place.onPointerDown}
        onPointerMove={(e) => {
          place.onPointerMove(e);
          onStroke(e);
        }}
        onPointerUp={place.onPointerUp}
        onKeyDown={place.onKeyDown}
        onClick={() => {
          // A drag just ended - swallow the synthetic click so the panel
          // doesn't toggle when the user only repositioned the avatar.
          if (place.consumeDrag()) return;
          if (chatOpen) setChatOpen(false);
          else setOpen((v) => !v);
        }}
        // Right-click: the pet menu (hide, size, choose, upload, import).
        onContextMenu={(e) => {
          e.preventDefault();
          setOpen(false);
          setChatOpen(false);
          setMenu(true);
        }}
        aria-label={open || chatOpen ? t("sagi.closeAvatar", { name }) : t("sagi.open", { name })}
        aria-expanded={open || chatOpen}
        title={t("sagi.avatarTitle", { name })}
      >
        {pet.id === "sagi" || !("kind" in pet) ? (
          <SagiAvatar
            mood={brain.mood}
            moment={reducedMotion ? null : brain.moment?.kind}
            reducedMotion={reducedMotion}
            size={size}
          />
        ) : (
          <PetSprite
            id={pet.id}
            kind={pet.kind}
            mood={brain.mood}
            // Dragged → runs that way; hovered → waves (Codex's pet does both).
            // A moment (a pat's hop) outranks the hover wave, or stroking the
            // pet would only ever show it waving.
            action={place.moving ? `run-${place.moving}` : hover && !brain.moment ? "wave" : null}
            moment={brain.moment?.kind}
            gaze={gaze}
            size={size}
            reducedMotion={reducedMotion}
            // Deleted elsewhere, or unreadable: back to Sagi.
            onBroken={() => sagiPrefs.setPet({ id: "sagi" })}
          />
        )}
        {brain.reaction && (
          <span key={brain.reaction.key} className="sagi-reaction" aria-live="polite">
            <span className="sagi-hearts" aria-hidden>
              <span>💜</span>
              <span>💗</span>
              <span>💜</span>
            </span>
            <span className="sagi-reaction-text" data-side={place.side}>
              {brain.reaction.text}
            </span>
          </span>
        )}
        {brain.status.errorCount > 0 ? (
          <span className="sagi-error-dot" aria-hidden>
            {brain.status.errorCount > 9 ? "9+" : brain.status.errorCount}
          </span>
        ) : (
          brain.status.waitingCount > 0 && (
            <span className="sagi-error-dot" data-kind="waiting" aria-hidden>
              {brain.status.waitingCount > 9 ? "9+" : brain.status.waitingCount}
            </span>
          )
        )}
      </button>
    </>
  );
}