/**
 * Normalized presentation model for the chat-style task thread (the default
 * task view; the classic legacy view sits behind enableClassicTaskInterface).
 *
 * This is a deliberately small, protocol-agnostic model that the new render
 * layer consumes. Two producers feed it:
 *   1. The dev harness, via synthetic fixtures (task-chat-fixtures.ts).
 *   2. The live thread, via an adapter over the existing comment/run props.
 *
 * Every field traces to a real agent-protocol concept (ACP SessionUpdate /
 * acpx AcpRuntimeEvent / TranscriptEntry). See DESIGN.md and the plan's state
 * inventory for the mapping. No timing/motion values live here — those are
 * CSS motion tokens in ui/src/index.css.
 */
import type {
  IssueAttachment,
  IssueCommentMetadata,
  IssueCommentPresentation,
  IssueDocument,
  IssueDocumentSummary,
  IssueWorkProduct,
} from "@paperclipai/shared";
import type {
  PaperclipQuestionResponse,
  PaperclipQuestionSet,
} from "@paperclipai/adapter-utils";

export type { PaperclipQuestionResponse, PaperclipQuestionSet };

export type TaskChatProviderActivityFamily =
  | "plan"
  | "tool_execution"
  | "research"
  | "delegation"
  | "model_identity"
  | "context"
  | "artifact"
  | "review"
  | "hook"
  | "memory"
  | "safety"
  | "terminal"
  | "wait"
  | "provider_notice";

export type TaskChatProviderActivityStatus =
  "running" | "completed" | "failed" | "interrupted" | "informational";

export interface TaskChatWorkspaceChangeFile {
  path: string;
  operation: "create" | "modify" | "delete" | "rename" | "mode_change";
  previousPath: string | null;
  additions: number | null;
  deletions: number | null;
  binary: boolean;
  diff: string | null;
}
import type { IssueThreadInteraction } from "@/lib/issue-thread-interactions";

/** Who authored a thread row — the primary legibility signal. */
export type TaskChatAuthorKind = "human" | "agent" | "system";

/** ACP ToolCallStatus. */
export type TaskChatToolStatus =
  "pending" | "in_progress" | "completed" | "failed" | "interrupted";

/** ACP PermissionOptionKind. */
export type TaskChatApprovalOptionKind =
  "allow_once" | "allow_always" | "reject_once" | "reject_always";

/** ACP PlanEntryStatus. */
export type TaskChatPlanEntryStatus = "pending" | "in_progress" | "completed";

/** ACP PlanEntryPriority. */
export type TaskChatPlanEntryPriority = "high" | "medium" | "low";

export interface TaskChatApprovalOption {
  id: string;
  label: string;
  kind: TaskChatApprovalOptionKind;
}

export interface TaskChatDiff {
  path?: string;
  added: number;
  removed: number;
  /** Optional unified-diff-ish lines for display only. */
  lines?: Array<{ kind: "add" | "remove" | "context"; text: string }>;
}

export interface TaskChatTokenUsage {
  /** ACP UsageUpdate.used — tokens in context. */
  used: number;
  /** ACP UsageUpdate.size — context window size. */
  size: number;
  inputTokens?: number;
  outputTokens?: number;
  costUsd?: number;
}

/** A human/agent/system message bubble. */
export interface TaskChatMessageItem {
  /** Stable UI identity through optimistic acknowledgement; id remains canonical. */
  renderKey?: string;
  id: string;
  kind: "message";
  author: TaskChatAuthorKind;
  authorName?: string;
  text: string;
  /** Runner-authored output channel. Legacy adapters leave this unset. */
  channel?: "progress" | "final" | "unknown";
  timestamp?: string;
  /** Show a streaming cursor and suppress collapse while true. */
  streaming?: boolean;
  /** Optimistic local echo state (matches IssueChatComment.clientStatus). */
  optimistic?: "pending" | "queued";
  /** Live run this queued message is waiting behind. */
  queueTargetRunId?: string | null;
  /** Non-blocking verification limitations attached to the run's durable reply. */
  verificationCaveats?: Array<{
    commandOrCheck: string;
    reasonCode?: string | null;
    detail?: string | null;
  }>;
  /** Assigned agent icon name (AgentIconName) for the avatar header. */
  agentIcon?: string | null;
  /**
   * Responsible user's display name, set only when this agent comment is a
   * cross-issue write (the author is not the assignee). Renders as a
   * "for {user}" chip beside the author name (the open cross-task write design (attribution)).
   */
  onBehalfOfUserName?: string;
  /** A transient provider progress update, distinct from the durable final response. */
  interstitial?: boolean;
  /** Epoch ms of the message's first streamed chunk. */
  atMs?: number;
  /** Index of the latest transcript event folded into this logical block. */
  transcriptIndex?: number;
  /**
   * The settled run turn "attached" to this bubble (round 9): when the run's
   * final reply lands, the live parent row transforms into the "Worked · …"
   * summary rendered on this bubble's always-visible timestamp line —
   * "2:34 PM · ✓ Worked · 38s · 3 tools" — instead of a standalone row.
   * Expanding still nests the tool history beneath the bubble.
   */
  attachedTurn?: TaskChatTurnItem;
  /**
   * Structured system-notice fields (PAP-443), carried only for
   * author === "system": either system attribution or an explicit
   * system_notice presentation routes the comment here. The comment's
   * server-authored presentation hints and metadata sections drive the
   * collapsed one-line row + expandable detail.
   */
  presentation?: IssueCommentPresentation | null;
  metadata?: IssueCommentMetadata | null;
  /** Agent that owns the source run, used to build run-detail links in metadata rows. */
  runAgentId?: string | null;
  /** Raw comment timestamp (ISO) — the collapsed system row shows relative time. */
  createdAtIso?: string;
}

/** Collapsed chain-of-thought (ACP agent_thought_chunk). */
export interface TaskChatThinkingItem {
  id: string;
  kind: "thinking";
  lines: string[];
  streaming?: boolean;
  /** When true, render collapsed ("Worked for N") with an expand affordance. */
  collapsed?: boolean;
  /** Human-readable elapsed label for the collapsed header. */
  summaryLabel?: string;
  /** Provider-emitted reasoning surface; never synthesized by the UI. */
  channel?: "summary" | "detail" | "unknown";
  /** A real provider reasoning lifecycle with no provider-authored text. */
  lifecycleOnly?: boolean;
  /** Index of the latest transcript event folded into this logical block. */
  transcriptIndex?: number;
}

/** A tool invocation row (ACP tool_call / tool_call_update). */
export interface TaskChatToolItem {
  id: string;
  kind: "tool";
  name: string;
  /** Raw ACP tool name pre-collapse ("mcp__server__tool") for taxonomy lookup. */
  rawName?: string;
  /** ACP ToolKind. */
  toolKind?: string;
  status: TaskChatToolStatus;
  /**
   * Summarized primary argument (file path, command, pattern…) rendered mono
   * next to the tool name — the v7 toolrow "target".
   */
  target?: string;
  detail?: string;
  diff?: TaskChatDiff;
  /** Resolved permission decision badge, when one applied. */
  decision?: "allowed" | "rejected";
}

/**
 * A lifecycle state rendered as a status affordance — never a bubble.
 * Covers both LIVE (running/working) and Tier-B (awaiting_approval,
 * interrupted, refused, truncated) states.
 */
export interface TaskChatStatusItem {
  id: string;
  kind: "status";
  status:
    | "running"
    | "working"
    | "awaiting_approval"
    | "interrupted"
    | "refused"
    | "truncated";
  label: string;
  detail?: string;
  /** Raw tool name of the in-flight tail tool_call (drives the pill's icon). */
  toolName?: string;
  /**
   * Flattened plain text of the interstitial update currently streaming
   * (PAP-361, round 9): it renders in a dedicated single-line row directly
   * above the status line — a slot PERMANENTLY RESERVED while the turn is
   * live, so the layout above never jumps — inside a one-line viewport
   * showing the streaming tail line; the gerund rotation below runs
   * uninterrupted. When the message finishes the pill HOLDS the text as a
   * static ellipsized line until the next update supersedes it or the turn
   * ends (PAP-368) — nothing persists in the settled thread.
   */
  selfTalk?: string;
  elapsedMs?: number;
  /** Run start epoch ms; live states tick their own elapsed from this. */
  startedAtMs?: number;
  tokens?: TaskChatTokenUsage;
  /** Present for awaiting_approval (ACP RequestPermissionRequest). */
  approval?: { toolName: string; options: TaskChatApprovalOption[] };
}

/** A lifecycle divider (session start, interruption, turn boundary). */
export interface TaskChatMarkerItem {
  id: string;
  kind: "marker";
  variant: "session_start" | "interrupted" | "turn_boundary";
  label: string;
  detail?: string;
  /** Renders the marker as a quiet disclosure row with detail beneath it. */
  collapsible?: boolean;
  /** Expected cancellation is neutral; unexpected failures remain destructive. */
  tone?: "neutral" | "error";
  runId?: string;
  createdAtIso?: string;
  runHref?: string;
}

/** A second-tier live token/cost readout (ACP UsageUpdate). */
export interface TaskChatUsageItem {
  id: string;
  kind: "usage";
  usage: TaskChatTokenUsage;
  /** Present when the measurement is not scoped to the current run. */
  label?: string;
  detail?: string;
}

export interface TaskChatActivityPhaseItem {
  id: string;
  kind: "activity_phase";
  /** Historical assistant update that introduced this phase. */
  interstitial?: TaskChatMessageItem;
  /** Chronological tool/usage rows owned exclusively by this phase. */
  items: Array<
    | TaskChatToolItem
    | TaskChatUsageItem
    | TaskChatThinkingItem
    | TaskChatMarkerItem
    | TaskChatProtocolItem
  >;
  /** Deterministic, taxonomy-based summary (for example "Read 3 files, ran 1 command"). */
  summary: string;
  /** The tail phase of an in-flight run stays foregrounded. */
  active: boolean;
}

/**
 * The task description rendered as the requester's first chat bubble
 * (PAP-375). A placeholder kind only — the host supplies the render
 * (TaskChatThread binds TaskChatDescriptionBubble to the live issue), mirroring
 * how interaction items defer to renderInteraction. Always prepended AFTER
 * thread assembly, so no backbone entry or settled turn can sort above it.
 */
export interface TaskChatBriefItem {
  id: string;
  kind: "brief";
}

/**
 * An issue-thread interaction (plan confirmation, question card, suggested
 * tasks…) interleaved chronologically into the thread. The payload is the
 * existing control-plane IssueThreadInteraction — the render layer wraps the
 * shared IssueThreadInteractionCard rather than re-modeling the five kinds.
 */
export interface TaskChatInteractionItem {
  id: string;
  kind: "interaction";
  interaction: IssueThreadInteraction;
}

/** A canonical, atomically saved Plan document interleaved into the thread. */
export interface TaskChatPlanDocumentItem {
  id: string;
  kind: "plan_document";
  document: IssueDocument;
  /** Distinguishes a proven semantic write boundary from lossless fallback. */
  placement?: "write_boundary" | "fallback";
}

export interface TaskChatProtocolDetail {
  label: string;
  value: string;
  mono?: boolean;
}

export interface TaskChatProtocolStep {
  id: string;
  label: string;
  status: "pending" | "in_progress" | "completed" | "blocked" | "failed";
}

export interface TaskChatProtocolLink {
  label: string;
  href: string;
  description?: string;
}

export interface TaskChatProtocolChild {
  id: string;
  title: string;
  status: string;
  metadata?: string;
  summary?: string;
}

export interface TaskChatProviderActivityItem {
  id: string;
  kind: "protocol";
  surface: "provider_activity";
  family: TaskChatProviderActivityFamily;
  eventType: string;
  status: TaskChatProviderActivityStatus;
  title: string;
  summary?: string;
  details: TaskChatProtocolDetail[];
  steps: TaskChatProtocolStep[];
  links: TaskChatProtocolLink[];
  children: TaskChatProtocolChild[];
  output?: string;
  outputTruncated?: boolean;
  /** Index of the latest provider event coalesced into this activity. */
  transcriptIndex?: number;
}

export interface TaskChatWorkspaceChangeItem {
  id: string;
  kind: "protocol";
  surface: "workspace_change";
  changeSetId: string;
  revision: number;
  source: "harness_reported" | "runner_verified";
  complete: boolean;
  files: TaskChatWorkspaceChangeFile[];
  totals: { files: number; additions: number | null; deletions: number | null };
  patchArtifactRef: string | null;
}

export interface TaskChatWorkspaceFileItem {
  id: string;
  kind: "protocol";
  surface: "workspace_file";
  referenceId: string;
  source: "harness_reported" | "runner_verified";
  path: string;
  displayName: string;
  mediaType: string | null;
  presentation: "document" | "code" | "image" | "generic";
  line: number | null;
  preview: string | null;
  previewTruncated: boolean;
}

export interface TaskChatRuntimeRequestItem {
  id: string;
  kind: "protocol";
  surface: "runtime_request";
  runId: string;
  requestId: string;
  requestKind:
    | "runtime"
    | "command_approval"
    | "file_approval"
    | "permission_approval"
    | "user_input"
    | "elicitation"
    | null;
  turnId: string | null;
  requestType: "permission" | "input";
  status: "pending" | "resolved" | "expired" | "cancelled";
  prompt: string;
  choices: Array<{ key: string; label: string }>;
  fields: Array<{ name: string; label: string; placeholder: string | null }>;
  questionSet?: PaperclipQuestionSet | null;
  resolvedAction?: string | null;
  response?: PaperclipQuestionResponse | null;
}

export type TaskChatRuntimeRequestDecision =
  | { action: "accept" | "accept_for_session" | "decline" | "cancel" }
  | { action: "submit"; values: Record<string, string> }
  | { action: "submit"; response: PaperclipQuestionResponse };

export interface TaskChatRunResultItem {
  id: string;
  kind: "protocol";
  surface: "run_result";
  disposition: "done" | "blocked" | "needs_review" | "yielded";
  summary: string;
  objectiveSatisfied: boolean | null;
  verification: Array<{
    commandOrCheck: string;
    status: "passed" | "failed" | "not_run";
    detail?: string;
    artifactRef?: string;
  }>;
  remainingWork: Array<{ description: string; blocksCompletion: boolean }>;
  blocker: {
    reasonCode: string;
    unblockAction: string;
    scope: "current_track" | "task_wide";
  } | null;
  artifacts: Array<{ kind: string; ref: string; title?: string }>;
  /** Proven by accepted native result and same-run successful terminal events. */
  acceptedResponseWake?: { runId: string; sourceEventId: string };
}

export interface TaskChatRunTerminalItem {
  id: string;
  kind: "protocol";
  surface: "run_terminal";
  turnState: "completed" | "failed" | "interrupted" | "cancelled";
  runState: "succeeded" | "failed" | "cancelled";
  disposition: "done" | "blocked" | "needs_review" | "yielded";
  stopReason?: string;
}

export interface TaskChatMaterializedResourceItem {
  id: string;
  kind: "protocol";
  surface: "resource";
  resourceKind: "document" | "deliverable" | "attachment";
  title: string;
  subtitle: string;
  href: string | null;
  timestamp?: string;
  document?: IssueDocumentSummary;
  workProduct?: IssueWorkProduct;
  attachment?: IssueAttachment;
}

export type TaskChatProtocolItem =
  | TaskChatProviderActivityItem
  | TaskChatWorkspaceChangeItem
  | TaskChatWorkspaceFileItem
  | TaskChatRuntimeRequestItem
  | TaskChatRunResultItem
  | TaskChatRunTerminalItem
  | TaskChatMaterializedResourceItem;

/** Items a turn can group — everything except another turn. */
export type TaskChatTurnChildItem =
  | TaskChatMessageItem
  | TaskChatThinkingItem
  | TaskChatToolItem
  | TaskChatStatusItem
  | TaskChatMarkerItem
  | TaskChatUsageItem
  | TaskChatActivityPhaseItem
  | TaskChatPlanDocumentItem
  | TaskChatProtocolItem;

/**
 * One agent turn's activity (thinking/tools/diffs) grouped so a finished turn
 * can fold into a one-line expandable summary ("✓ Worked · 38s · 3 tools ·
 * +34 −3"). A live turn carrying `liveStatus` renders as a single expandable
 * parent row headed by that status line (gerund/tool-state + elapsed +
 * tokens); expanding nests the chronological activity underneath, and on
 * settle the header morphs in place into the summary. The live → settled
 * fold animates (~ --motion-turn-fold), while turns that load already-settled
 * collapse instantly.
 */
export interface TaskChatTurnItem {
  id: string;
  kind: "turn";
  items: TaskChatTurnChildItem[];
  settled: boolean;
  /** Agent identity retained when a live runner turn becomes durable history. */
  agentName?: string;
  agentIcon?: string | null;
  /**
   * The in-flight run's status line, hoisted to be THE turn's single visible
   * row while collapsed (PAP-354 parent-row model). Absent once settled.
   */
  liveStatus?: TaskChatStatusItem;
  /** Animate the fold when settling (false = collapse instantly, e.g. history). */
  animateFold?: boolean;
  /** New-runner turns keep Worked/Stopped fixed above their ordered timeline. */
  standaloneHeader?: boolean;
  /** This segment resumes the same native run after a steering input. */
  continuedAfterSteering?: boolean;
  /** Durable response shown after the ordered Paperclip Runner timeline. */
  finalResponse?: TaskChatMessageItem;
  summary: {
    /** e.g. "38s" — omitted when unknown. */
    durationLabel?: string;
    toolCount: number;
    added: number;
    removed: number;
    /** e.g. "12.3k tokens" — omitted when unknown. */
    tokensLabel?: string;
    /** Failed/interrupted turns get a ✗ affordance instead of ✓. */
    failed?: boolean;
  };
}

export interface TaskChatProjectCreatedItem {
  id: string;
  kind: "project_created";
  projectId: string;
  name: string;
  description?: string | null;
  repositories: { id: string; name: string; url: string }[];
  timestamp: string;
}

export type TaskChatItem =
  | TaskChatProjectCreatedItem
  | TaskChatMessageItem
  | TaskChatThinkingItem
  | TaskChatToolItem
  | TaskChatStatusItem
  | TaskChatMarkerItem
  | TaskChatUsageItem
  | TaskChatActivityPhaseItem
  | TaskChatInteractionItem
  | TaskChatPlanDocumentItem
  | TaskChatTurnItem
  | TaskChatBriefItem
  | TaskChatProtocolItem;

/** Latest lifecycle state wins for each request; terminal entries suppress stale pending cards. */
export function latestPendingRuntimeRequest(
  items: readonly TaskChatItem[],
): TaskChatRuntimeRequestItem | null {
  const seen = new Set<string>();
  for (let index = items.length - 1; index >= 0; index -= 1) {
    const item = items[index];
    if (item.kind !== "protocol" || item.surface !== "runtime_request")
      continue;
    const key = `${item.runId}:${item.requestId}`;
    if (seen.has(key)) continue;
    seen.add(key);
    if (item.status === "pending") return item;
  }
  return null;
}

/** A protocol denial is the explicit negative path, so a second Skip action is redundant. */
export function runtimeRequestReplacesComposerSkip(
  item: TaskChatRuntimeRequestItem,
): boolean {
  return item.choices.some((choice) => {
    const key = choice.key.trim().toLowerCase();
    const label = choice.label.trim().toLowerCase();
    return (
      ["deny", "decline", "reject"].includes(key) ||
      /^(deny|decline|reject)(\b|\s)/.test(label)
    );
  });
}

/** One latest lifecycle entry per request, in the order each request began. */
export function latestRuntimeRequests(
  items: readonly TaskChatItem[],
): TaskChatRuntimeRequestItem[] {
  const latest = new Map<
    string,
    { order: number; item: TaskChatRuntimeRequestItem }
  >();
  for (const [order, item] of items.entries()) {
    if (item.kind !== "protocol" || item.surface !== "runtime_request")
      continue;
    const key = `${item.runId}:${item.requestId}`;
    const existing = latest.get(key);
    latest.set(key, { order: existing?.order ?? order, item });
  }
  return [...latest.values()]
    .sort((left, right) => left.order - right.order)
    .map(({ item }) => item);
}

/** A structured plan entry (ACP PlanEntry) for the Plans tab. */
export interface TaskChatPlanEntry {
  id: string;
  content: string;
  status: TaskChatPlanEntryStatus;
  priority: TaskChatPlanEntryPriority;
}

export interface TaskChatPlan {
  /** Revision index (1-based); higher supersedes. */
  revision: number;
  entries: TaskChatPlanEntry[];
  updatedAt?: string;
}