// One transcript row, by kind. docs/STRUCTURED-VIEW.md fixes the eight kinds
// and leaves every rendering decision here: markdown for AgentText, an inline
// italic stream for AgentThought, a tool card for ToolCall/ToolDiff, a diff
// view for ToolDiff's content, an approval card for Approval, and an opaque
// collapsed line for a Notice nobody has taught the client about. `Plan` is
// deliberately not drawn — the web client has no plan rail.

import { useEffect, useRef, type ReactNode } from "react";

import { renderInlineMarkdown, renderMarkdown, formatElapsed } from "./render.js";
import type {
  AcpContentBlock,
  AcpPermissionOption,
  AcpToolCallContent,
  AcpToolCallLike,
  StructuredApprovalDecision,
  TranscriptRow as Row,
  TurnMeta,
} from "../../types.js";
import { ApprovalView } from "./ApprovalView.js";
import { Copyable } from "./Copyable.js";
import { DiffView } from "./DiffView.js";
import {
  contentBlockText,
  isStateOnlyNotice,
  splitToolTitle,
  statusMeta,
  toolDiffMeta,
  turnMeta,
} from "./model.js";
import { safeMediaSource, toolPayload } from "./toolPayload.js";
import { ToolIcon } from "./ToolIcon.js";

// ---------------------------------------------------------------------------
// content rows: user / agent / thought
// ---------------------------------------------------------------------------

/** Model-authored markdown, sanitized by render.ts before it enters
 *  the DOM. Tables get their own scroller and links open out of the app. */
function Prose({ html }: { html: string }) {
  const ref = useRef<HTMLDivElement | null>(null);
  useEffect(() => {
    const container = ref.current;
    if (!container) return;
    for (const table of Array.from(container.querySelectorAll("table"))) {
      if (table.parentElement?.classList.contains("st-markdown-table-wrap")) continue;
      const scroller = document.createElement("div");
      scroller.className = "st-markdown-table-wrap";
      table.replaceWith(scroller);
      scroller.appendChild(table);
    }
    for (const link of container.querySelectorAll("a")) {
      link.target = "_blank";
      link.rel = "noopener noreferrer";
    }
  }, [html]);
  return <div ref={ref} className="st-body" dangerouslySetInnerHTML={{ __html: html }} />;
}

export interface ContentRowProps {
  row: Row;
  variant: "user" | "agent" | "thought";
  /** Object URLs for images this prompt uploaded, keyed by the server path the
   *  row's text names. */
  imageUrls?: Map<string, string>;
}

/** `Attached file "name": "path"` references the composer appends on send. */
const ATTACHED_FILE_RE = /Attached file "(?:[^"\\]|\\.)*": "((?:[^"\\]|\\.)*)"/g;

function attachedImages(text: string, imageUrls: Map<string, string>): string[] {
  const urls: string[] = [];
  ATTACHED_FILE_RE.lastIndex = 0;
  let match: RegExpExecArray | null;
  while ((match = ATTACHED_FILE_RE.exec(text)) !== null) {
    let serverPath: string;
    try {
      serverPath = JSON.parse(`"${match[1]}"`) as string;
    } catch {
      continue;
    }
    const url = imageUrls.get(serverPath);
    if (url) urls.push(url);
  }
  return urls;
}

export function ContentRow({ row, variant, imageUrls }: ContentRowProps) {
  const data = row.data as { content?: AcpContentBlock } | undefined;
  const text = contentBlockText(data?.content);
  const displayText = variant === "thought" ? text.trim() : text;
  const label = variant === "user" ? "message" : variant === "agent" ? "response" : "thought";

  let body: ReactNode;
  if (variant === "user") {
    const images = imageUrls && imageUrls.size > 0 ? attachedImages(displayText, imageUrls) : [];
    // With previews in hand the path references are noise — the image is the
    // attachment. Without them the text is all the operator has, so it stays.
    const shown =
      images.length > 0
        ? displayText.replace(/\n\nAttached file "[^"]*": "[^"]*"/g, "").trim()
        : displayText;
    body = (
      <div className="st-body">
        {shown && <div className="st-user-text">{shown}</div>}
        {images.map((src) => (
          <img key={src} className="st-user-image" src={src} alt="Uploaded image" loading="lazy" />
        ))}
      </div>
    );
  } else if (variant === "agent") {
    body = <Prose html={renderMarkdown(displayText)} />;
  } else {
    body = <div className="st-body" dangerouslySetInnerHTML={{ __html: renderInlineMarkdown(displayText) }} />;
  }

  return (
    <Copyable className={`st-row st-row-${variant}`} text={displayText} label={label} data-row-id={row.id}>
      {body}
    </Copyable>
  );
}

// ---------------------------------------------------------------------------
// tool rows
// ---------------------------------------------------------------------------

function ToolDetailBlock({ label, text }: { label: string; text: string }) {
  return (
    <div className="st-tool-detail">
      <div className="st-tool-detail-label">{label}</div>
      <Copyable as="pre" text={text} label={label.toLowerCase()}>
        {text}
      </Copyable>
    </div>
  );
}

function ContentBlockView({ block }: { block: AcpContentBlock }) {
  if (block.type === "text") {
    if (!block.text) return null;
    return (
      <Copyable className="st-tool-text" text={block.text} label="output">
        {block.text}
      </Copyable>
    );
  }
  if (block.type === "image") {
    const source = safeMediaSource(block.mimeType, block.data, "image");
    if (source) return <img className="st-tool-image" src={source} alt="Tool output" loading="lazy" />;
    return <ToolDetailBlock label="Image" text={block.uri ?? block.mimeType ?? "Unavailable"} />;
  }
  if (block.type === "audio") {
    const source = safeMediaSource(block.mimeType, block.data, "audio");
    if (source) return <audio className="st-tool-audio" controls src={source} />;
    return <ToolDetailBlock label="Audio" text={block.mimeType ?? "Unavailable"} />;
  }
  if (block.type === "resource_link") {
    return (
      <div className="st-tool-resource">
        <span className="st-tool-resource-name">{block.title ?? block.name ?? "Resource"}</span>
        {block.uri && (
          <Copyable as="code" className="st-tool-resource-uri" text={block.uri} label="resource URI">
            {block.uri}
          </Copyable>
        )}
        {block.description && <span className="st-tool-resource-description">{block.description}</span>}
      </div>
    );
  }
  const resource = block.resource;
  if (typeof resource?.text === "string") {
    return (
      <ToolDetailBlock label={resource.uri ? `Resource · ${resource.uri}` : "Resource"} text={resource.text} />
    );
  }
  const printed = resource === undefined ? "" : JSON.stringify(resource, null, 2);
  return printed ? <ToolDetailBlock label="Resource" text={printed} /> : null;
}

function ToolBody({ tool, content }: { tool: AcpToolCallLike; content: AcpToolCallContent[] }) {
  const payload = toolPayload(tool, content);
  const hasRaw = payload.raw.input !== null || payload.raw.output !== null;
  return (
    <>
      {content.map((block, index) => {
        if (block.type === "content") return <ContentBlockView key={index} block={block.content} />;
        if (block.type === "diff") return <DiffView key={index} diff={block} />;
        return (
          <div key={index} className="st-tool-terminal">
            {block.terminalId ? `Terminal · ${block.terminalId}` : "Embedded terminal"}
          </div>
        );
      })}
      {payload.details.map((detail, index) => (
        <ToolDetailBlock key={`${detail.label}-${index}`} label={detail.label} text={detail.text} />
      ))}
      {payload.exitCode !== null && (
        <div className="st-tool-fact">
          <span className="st-tool-fact-label">Exit code</span>
          <code className={payload.exitCode === 0 ? "st-tool-exit-ok" : "st-tool-exit-failed"}>
            {payload.exitCode}
          </code>
        </div>
      )}
      {hasRaw && (
        <details className="st-tool-raw">
          <summary>Raw JSON</summary>
          <div className="st-tool-raw-body">
            {payload.raw.input !== null && <ToolDetailBlock label="Input" text={payload.raw.input} />}
            {payload.raw.output !== null && <ToolDetailBlock label="Output" text={payload.raw.output} />}
          </div>
        </details>
      )}
    </>
  );
}

/** True when a tool call has anything at all to disclose — a head with nothing
 *  behind it stays a plain line rather than an empty disclosure. */
function hasToolBody(tool: AcpToolCallLike, content: AcpToolCallContent[]): boolean {
  if (content.length > 0) return true;
  const payload = toolPayload(tool, content);
  return payload.details.length > 0 || payload.exitCode !== null || payload.raw.input !== null || payload.raw.output !== null;
}

export interface ToolRowProps {
  row: Row;
  expanded: boolean;
  onExpandedChange(expanded: boolean): void;
}

export function ToolRow({ row, expanded, onExpandedChange }: ToolRowProps) {
  const tool = (row.data ?? {}) as AcpToolCallLike;
  const content = tool.content ?? [];
  const hasDiff = content.some((c) => c.type === "diff");
  const { label, arg } = splitToolTitle(tool.title, tool.name, tool.kind);
  const meta = statusMeta(tool.status, hasDiff);
  const metaParts: string[] = [];
  if (hasDiff) metaParts.push(toolDiffMeta(content));
  if (meta) metaParts.push(meta.text);
  const disclosable = hasToolBody(tool, content);
  const open = expanded && disclosable;

  return (
    <div className="st-row st-row-tool" data-row-id={row.id}>
      <div className="st-tool">
        <button
          type="button"
          className="st-tool-head"
          aria-expanded={open}
          onClick={() => disclosable && onExpandedChange(!open)}
        >
          <ToolIcon kind={tool.kind} />
          <span className="st-tool-name">{label}</span>
          <span className="st-tool-arg" title={arg}>
            {arg}
          </span>
          {metaParts.length > 0 && (
            <span className={meta ? `st-tool-meta st-tool-meta-${meta.kind}` : "st-tool-meta"}>
              {metaParts.join(" · ")}
            </span>
          )}
        </button>
        {disclosable && (
          <div
            className={open ? "st-tool-out st-disclosure is-expanded" : "st-tool-out st-disclosure"}
            aria-hidden={!open}
            inert={!open}
          >
            <div className="st-disclosure-clip">
              <div className="st-disclosure-inner">
                {/* Built only once opened: a long transcript would otherwise
                    render every tool's whole output up front. */}
                {open && <ToolBody tool={tool} content={content} />}
              </div>
            </div>
          </div>
        )}
      </div>
    </div>
  );
}

// ---------------------------------------------------------------------------
// notices and turn footers
// ---------------------------------------------------------------------------

function compactNumber(value: number): string {
  if (Math.abs(value) < 1_000) return String(value);
  if (Math.abs(value) < 1_000_000) return `${(value / 1_000).toFixed(value % 1_000 === 0 ? 0 : 1)}k`;
  return `${(value / 1_000_000).toFixed(value % 1_000_000 === 0 ? 0 : 1)}m`;
}

export function TurnMetaRow({ meta }: { meta: TurnMeta }) {
  const parts = [formatElapsed(meta.elapsedMs)];
  if (typeof meta.contextDelta === "number") {
    const sign = meta.contextDelta > 0 ? "+" : "";
    parts.push(`${sign}${compactNumber(meta.contextDelta)} context tokens`);
  } else if (typeof meta.contextTokens === "number") {
    parts.push(`${compactNumber(meta.contextTokens)} context`);
  }
  if (meta.model) parts.push(meta.model);
  if (meta.outcome !== "completed") parts.push(meta.outcome);
  const text = parts.join(" · ");
  return (
    <Copyable
      className={`st-turn-meta st-turn-meta-${meta.outcome}`}
      text={text}
      label="turn details"
      aria-label={`Turn ${meta.outcome}`}
    >
      <span className="st-turn-meta-dot" aria-hidden="true" />
      <span>{text}</span>
    </Copyable>
  );
}

/** The floor presentation docs/STRUCTURED-VIEW.md allows for a `Notice` the
 *  client has nothing better to do with: an opaque, collapsed line. */
export function NoticeRow({ row }: { row: Row }) {
  const text = `[${row.kind}]`;
  return (
    <Copyable className="st-row st-row-notice" text={text} label="notice" data-row-id={row.id}>
      <div className="st-body">{text}</div>
    </Copyable>
  );
}

// ---------------------------------------------------------------------------
// dispatch
// ---------------------------------------------------------------------------

export interface TranscriptRowProps {
  row: Row;
  /** This row is the one live approval (docs/STRUCTURED-VIEW.md's nonce
   *  rules). Every other approval row is history. */
  pendingApproval?: boolean;
  onDecide?: (decision: StructuredApprovalDecision) => Promise<void>;
  expanded?: boolean;
  onExpandedChange?: (expanded: boolean) => void;
  imageUrls?: Map<string, string>;
}

/** One transcript row, or `null` for the rows the web client omits (`plan`,
 *  and the state-only notices it consumes for `/` autocomplete). */
export function TranscriptRow({
  row,
  pendingApproval = false,
  onDecide,
  expanded = false,
  onExpandedChange,
  imageUrls,
}: TranscriptRowProps) {
  switch (row.kind) {
    case "user":
      return <ContentRow row={row} variant="user" imageUrls={imageUrls} />;
    case "agent_text":
      return <ContentRow row={row} variant="agent" />;
    case "agent_thought":
      return <ContentRow row={row} variant="thought" />;
    case "tool_call":
    case "tool_diff":
      return (
        <ToolRow row={row} expanded={expanded} onExpandedChange={(next) => onExpandedChange?.(next)} />
      );
    case "approval": {
      const request = (row.data ?? {}) as { toolCall?: AcpToolCallLike; options?: AcpPermissionOption[] };
      return (
        <ApprovalView
          request={request}
          pending={pendingApproval}
          onDecide={onDecide ?? (() => Promise.resolve())}
        />
      );
    }
    case "plan":
      return null;
    case "notice": {
      if (isStateOnlyNotice(row)) return null;
      const meta = turnMeta(row);
      return meta ? <TurnMetaRow meta={meta} /> : <NoticeRow row={row} />;
    }
    default:
      return <NoticeRow row={row} />;
  }
}