import { escapeHtml } from "./html.js";

// Mirror of `maestro-protocol` JSON shapes. Keep in sync with
// crates/maestro-protocol/src/lib.rs.

export type Uuid = string;
export type IsoTimestamp = string;

/** `Dormant` (#162) is a session the daemon knows only from its sidecar —
 * recovered after the tmux server died under it, so there is no pane behind it
 * and nothing to attach to. Listed, never live. */
export type SessionStatus = "Running" | "Dead" | "Dormant";

/** Daemon-inferred activity dimension, orthogonal to `SessionStatus` (NAP-340).
 * Absent on payloads from daemons that predate the field. `Error` is only set
 * when an agent reports failure (#105); the daemon never infers it. */
export type ActivityState = "Active" | "Idle" | "AwaitingInput" | "Error";

export interface Session {
  id: Uuid;
  cwd: string;
  command: string;
  env: Record<string, string>;
  metadata: Record<string, unknown>;
  status: SessionStatus;
  created_at: IsoTimestamp;
  /** Current foreground command in the pane (e.g. `claude`, `bash`), as the
   * daemon's activity watcher observed it. Absent until observed (NAP-340). */
  foreground?: string | null;
  /** Inferred activity. Defaults to `Idle` on the wire when omitted. */
  activity?: ActivityState;
  /** Short human string an agent reported alongside its state (#105) — e.g.
   * why it is in `Error`. Shown on a sidebar card's meta line while the
   * report is in force; cleared when the report lapses or is replaced. */
  activity_detail?: string | null;
  /** Wall-clock of the most recent observed PTY output (NAP-340). */
  last_activity_at?: IsoTimestamp;
  /** Wall-clock of when the session entered its current `activity` state
   * (#102) — distinct from `last_activity_at`, which only tracks PTY output.
   * Defaults to the Unix epoch on payloads from daemons that predate the
   * field. */
  activity_since?: IsoTimestamp;
  /** The pane's *current* working directory, as the daemon's activity watcher
   * observed it (`#{pane_current_path}`) — distinct from `cwd` (the spawn dir).
   * Drives the directory-based session tree. Absent until first observed. */
  current_cwd?: string | null;
  /** What currently blocks an unforced kill of this session (#83), as the
   * daemon's watcher last probed it. Absent until probed and for sessions
   * without a worktree; all counts default to 0 on the wire for older
   * daemons. */
  blocked_work?: InTheWay | null;
  /** The worktree the daemon created for this session, absent when it did not
   * create one. `base_repo` is the repository's main checkout, which is what
   * the session tree groups by (#99). */
  worktree?: SessionWorktree | null;
  /** Wall-clock of when this session last became the pane a client was showing
   * (#145) — stamped by both `POST /api/sessions/:id/focus` and opening
   * `/api/attach/:id`. Absent until the session has been focused once, which is
   * how the command bar's empty query sorts a never-focused session after every
   * session that has one (`docs/COMMAND-BAR.md`). */
  last_focused_at?: IsoTimestamp | null;
}

/** A session's daemon-created worktree (`SessionWorktree` on the wire). */
export interface SessionWorktree {
  path: string;
  base_repo: string;
}

/** One directory's immediate subdirectories (NAP-329). */
export interface DirListing {
  /** Resolved absolute directory that was listed (after ~/relative expansion). */
  path: string;
  /** Immediate subdirectory names, sorted case-insensitively. */
  entries: string[];
  /** True when the listing was capped server-side. */
  truncated?: boolean;
}

/** A spawn-form command preset advertised by the daemon (#22/#26). The `custom`
 * preset has an empty `command` and reveals the free-text command input. */
export interface SpawnPreset {
  id: string;
  label: string;
  command: string;
}

/** `GET /api/info` — the daemon's identity plus its spawn presets (#26).
 * Mirrors the daemon-side `DaemonInfo`. */
export interface DaemonInfo {
  hostname: string;
  version: string;
  /** Home dir of the user the daemon runs as; used to prefill the spawn form's
   * working directory. Empty/absent for older daemons. */
  home_dir?: string;
  /** Command presets (claude/opencode/zsh + custom), config-resolved. */
  presets: SpawnPreset[];
  /** Which commit the daemon was built from. Absent on older daemons. */
  build?: BuildInfo;
  /** Identity of the daemon *process*, regenerated on every start — a changed
   * value across a reconnect means the daemon restarted. Absent on older
   * daemons, which the restart flow treats as "cannot tell". */
  instance?: string;
  /** Canonical leader key the operator configured (`[tui].leader`, default
   * `ctrl-a`), so the web binds the same chord the TUI does (#159). Absent or
   * empty on an older daemon; the client then keeps its own default. */
  leader?: string;
}

/** Build provenance of the running daemon: what the status indicator names in
 * its tooltip, and what tells an upgrade apart from a plain restart. Every
 * field is empty when the binary was built outside a git checkout. */
export interface BuildInfo {
  /** Abbreviated commit hash. */
  commit: string;
  /** Commit date, RFC 3339. */
  commit_date: string;
  /** Whether the tree had uncommitted changes at build time. */
  dirty: boolean;
}

/** One deduplicated recent working dir for the spawn form's recents picker
 * (#24/#26). */
export interface RecentDir {
  cwd: string;
  last_command: string;
  last_used: IsoTimestamp;
}

/** `GET /api/recent-dirs` — the daemon's recent working dirs (#26). */
export interface RecentDirs {
  dirs: RecentDir[];
  truncated?: boolean;
}

/** `GET /api/gitroot?path=` — the enclosing repo toplevel of a path, or absent
 * when the path isn't inside a repo (#26). */
export interface GitRoot {
  root?: string;
}

/** `GET /api/names?count=N` — a batch of fresh session handles (#53). Mirrors
 * `maestro_protocol::NameBatch`. */
export interface NameBatch {
  names: string[];
}

/** One discovered git repository (or linked worktree) for `GET /api/projects`
 * (#54). Mirrors `maestro_protocol::Project`. */
export interface Project {
  /** Absolute path of the repository/worktree toplevel. */
  path: string;
  /** Basename of `path`. */
  name: string;
  is_worktree?: boolean;
  /** The main checkout this worktree belongs to; absent on plain repos. */
  base_repo?: string;
  /** Later of the repo's git HEAD mtime and the newest spawn-history use of
   * any directory inside it; absent when neither is known. */
  last_activity?: IsoTimestamp;
  /** Command last spawned in this project, from spawn history. */
  last_command?: string;
}

/** `GET /api/projects` — every discovered project, sorted by the daemon
 * newest-activity-first (#54). */
export type Projects = Project[];

export interface WorktreeSpec {
  base_repo: string;
  branch: string;
  /** When false, `branch` already exists and is checked out as-is (#61).
   * Defaults to true (create a new branch) on older daemons. */
  create_branch?: boolean;
}

/** One local branch of the enclosing repository, from `GET /api/branches`
 * (#55). Mirrors `maestro_protocol::BranchInfo`. */
export interface BranchInfo {
  /** Short branch name (`main`, `feature/foo`). */
  name: string;
  /** Whether this branch is the main checkout's current HEAD. */
  is_head: boolean;
  /** Toplevel path of the linked worktree holding this branch, if any. */
  worktree?: string | null;
}

/** `GET /api/branches?path=` — the local branches of one repository (#55). */
export type Branches = BranchInfo[];

/** What currently blocks an unforced kill of a worktree's session (#80),
 * recomputed by the daemon on every read. All counts default to 0 on the
 * wire for older daemons. */
export interface InTheWay {
  uncommitted_files?: number;
  untracked_files?: number;
  unpushed_commits?: number;
  /** Lines added across the tracked changes, staged and unstaged together. */
  insertions?: number;
  /** Lines removed across the same tracked changes. */
  deletions?: number;
}

/** One fragment of the sidebar's compact blocked-work stat (docs/SIDEBAR.md).
 * `kind` picks the colour; `text` is what the client prints. */
export interface BlockerStat {
  kind: "add" | "del" | "files" | "untracked" | "unpushed";
  text: string;
}

/** The blocked-work breakdown as diff notation: `+124 -18 ?3 ↑2`.
 *
 * The line counts cover tracked changes only, so a tree whose only tracked
 * change carries no line delta — a mode change, a rename — falls back to the
 * file count (`~2`) rather than claiming `+0 -0`. Both clients render exactly
 * these fragments; the spelled-out {@link formatInTheWay} survives in the
 * tooltip and in the kill refusal. */
export function blockerStats(w: InTheWay): BlockerStat[] {
  const stats: BlockerStat[] = [];
  const added = w.insertions ?? 0;
  const removed = w.deletions ?? 0;
  const changed = w.uncommitted_files ?? 0;
  if (added > 0 || removed > 0) {
    if (added > 0) stats.push({ kind: "add", text: `+${added}` });
    if (removed > 0) stats.push({ kind: "del", text: `-${removed}` });
  } else if (changed > 0) {
    stats.push({ kind: "files", text: `~${changed}` });
  }
  if ((w.untracked_files ?? 0) > 0)
    stats.push({ kind: "untracked", text: `?${w.untracked_files}` });
  if ((w.unpushed_commits ?? 0) > 0)
    stats.push({ kind: "unpushed", text: `\u2191${w.unpushed_commits}` });
  return stats;
}

/** The phrasing `maestro_protocol::InTheWay`'s Display impl uses — shared by
 * the kill refusal, the TUI and this client, so no two clients can describe
 * the same tree differently. Zero parts are omitted; all-zero renders
 * "no unsaved work". */
export function formatInTheWay(w: InTheWay): string {
  const parts: string[] = [];
  const push = (n: number | undefined, unit: string): void => {
    if (!n || n <= 0) return;
    parts.push(n === 1 ? `1 ${unit}` : `${n} ${unit}s`);
  };
  push(w.uncommitted_files, "uncommitted file");
  push(w.untracked_files, "untracked file");
  push(w.unpushed_commits, "unpushed commit");
  return parts.length > 0 ? parts.join(", ") : "no unsaved work";
}

/** #83: this session's blocked-work breakdown when something actually blocks
 * an unforced kill; `null` while clear or not yet probed. Render it with
 * {@link formatInTheWay} so every client phrases it identically. */
export function sessionBlockers(s: Session): InTheWay | null {
  const w = s.blocked_work;
  if (!w) return null;
  const blocked =
    (w.uncommitted_files ?? 0) > 0 ||
    (w.untracked_files ?? 0) > 0 ||
    (w.unpushed_commits ?? 0) > 0;
  return blocked ? w : null;
}

export interface CreateSessionRequest {
  cwd: string;
  command: string;
  env?: Record<string, string>;
  metadata?: Record<string, unknown>;
  worktree?: WorktreeSpec;
}

export type CatalogEvent =
  | { type: "Snapshot"; sessions: Session[] }
  | { type: "SessionAdded"; session: Session }
  | { type: "SessionRemoved"; id: Uuid }
  | { type: "SessionUpdated"; session: Session }
  | { type: "Lagged"; skipped: number };

export type ClientControl =
  | { type: "Resize"; cols: number; rows: number }
  | { type: "Ping" }
  | { type: "Pong" }
  | { type: "Error"; code: string; message: string };

export interface ApiError {
  error: {
    code: string;
    message: string;
    /** Set only by the kill guard (#79): what blocked the unforced kill. */
    unsaved_work?: InTheWay;
  };
}

export function sessionName(s: Session): string {
  return customSessionName(s) ?? s.command;
}

/** The session's own name, without the command fallback (#125): `undefined`
 * for a session that was never given one. */
export function customSessionName(s: Session): string | undefined {
  const meta = s.metadata as Record<string, unknown>;
  const name = meta?.name;
  if (typeof name === "string" && name.length > 0) return name;
  return undefined;
}

/** Where a session's name came from (#131). Mirrors
 * `maestro_protocol::NameSource`. */
export type NameSource = "User" | "Generated" | "Haiku";

/** Read `metadata.name_source`, leniently: anything unrecognised — including
 * a session named before the field existed — is a settled `User` name, so an
 * existing name is never dimmed or overwritten. */
export function nameSource(s: Session): NameSource {
  const meta = s.metadata as Record<string, unknown>;
  const source = meta?.name_source;
  if (source === "Generated" || source === "Haiku") return source;
  return "User";
}

/** Whether line 1 renders the name as provisional (#131): a handle the daemon
 * generated at spawn and may still replace with one derived from the first
 * prompt. See docs/SIDEBAR.md. */
export function isProvisionalName(s: Session): boolean {
  return customSessionName(s) !== undefined && nameSource(s) === "Generated";
}

/** Longest session name the daemon stores (#125), in characters. Mirrors
 * `maestro_protocol::MAX_SESSION_NAME_LEN`. */
export const MAX_SESSION_NAME_LEN = 64;

/** Trim a requested session name and cap it at {@link MAX_SESSION_NAME_LEN}
 * characters. Empty means "clear the name", so the card falls back to the
 * command. Mirrors `maestro_protocol::normalize_session_name` — the daemon
 * applies the same rule, this only keeps the UI honest about what it will
 * get back. Uses the spread so the cap counts code points, not UTF-16 units. */
export function normalizeSessionName(name: string): string {
  return [...name.trim()].slice(0, MAX_SESSION_NAME_LEN).join("");
}

/** The directory a session lives in: its live `current_cwd` if the daemon has
 * observed one, else the spawn `cwd`. */
export function sessionCwd(s: Session): string | undefined {
  if (typeof s.current_cwd === "string" && s.current_cwd) return s.current_cwd;
  return s.cwd || undefined;
}

/** Where a session sits in the directory tree. A worktree session belongs to
 * its repository, not to the worktree (#99): otherwise `~/tea/agent-skills`
 * grows a `~/tea/agent-skills/worktrees/largo-clarinet` folder holding one
 * session of the same name, and the repository stops being where you look for
 * the work. `base_repo` is the main checkout — the daemon resolves it. */
export function sessionTreePath(s: Session): string | undefined {
  const repo = s.worktree?.base_repo;
  if (typeof repo === "string" && repo) return repo;
  return sessionCwd(s);
}

/** Collapse a daemon's home dir to `~`. `home` comes from `DaemonInfo.home_dir`;
 * absent/empty leaves the path untouched. Mirrors the CLI's `abbreviate_dir`. */
export function abbreviateCwd(cwd: string, home?: string): string {
  if (home && (cwd === home || cwd.startsWith(`${home}/`))) {
    return `~${cwd.slice(home.length)}`;
  }
  return cwd;
}

/** `~/git.naps.pt/naps62/maestro` → `~/g/n/maestro`: keep the last segment
 * verbatim, collapse every earlier one to its first character. Two-or-fewer
 * segments are left alone (nothing to gain). Returns escaped HTML with the
 * collapsed stem wrapped in `.folder-stem` so callers' CSS can dim it. Shared
 * by the sidebar tree and the spawn dialog's recent-directory picker so both
 * abbreviate paths identically. */
export function abbreviateFolderName(name: string): string {
  const parts = name.split("/");
  if (parts.length <= 2) return escapeHtml(name);
  const last = parts[parts.length - 1];
  const stem = parts
    .slice(0, -1)
    .map((p) => (p === "~" ? "~" : Array.from(p)[0] ?? ""))
    .join("/");
  return `<span class="folder-stem">${escapeHtml(stem)}/</span>${escapeHtml(last)}`;
}