/**
 * KHAELOR
 * File: src/tui/components/tool-line.ts
 * Description: Tool call presentation — collapsed one-liners, live rows with timers, printed expansion blocks (TUI_DESIGN §6).
 *
 * Author: Simon-Pierre Boucher
 * Contact: contact@spboucher.ai
 */

import { truncateAnsi, visibleWidth } from "../renderer/ansi.js";
import type { StyleRole, Theme } from "../theme.js";

export type ToolOutcome = "ok" | "failed" | "cancelled";

/** UI tool kind (EVENT_MODEL `ui.kind`) — drives the `▸` glyph color. */
export type ToolLineKind = "read" | "search" | "edit" | "exec" | "process";

/** One color per tool family; the glyph shape stays `▸` in monochrome. */
const KIND_COLOR: Record<ToolLineKind, StyleRole> = {
  read: "cyan",
  search: "violet",
  edit: "warning",
  exec: "success",
  process: "teal",
};

function glyphFor(kind: ToolLineKind | undefined, theme: Theme): string {
  return theme.paint(kind !== undefined ? KIND_COLOR[kind] : "dim", "▸");
}

export interface SettledToolLine {
  /** Real result summary from the tool, e.g. `Search "ContextEngine" · 14 matches`. */
  summary: string;
  outcome: ToolOutcome;
  /** Turn-local index shown for post-hoc expansion (`/tool 3`). */
  index?: number;
  /** Tool family — colors the `▸` glyph (dim when unknown). */
  kind?: ToolLineKind;
}

/**
 * Settled one-liner: `▸` dim, summary from real tool results, failures marked
 * with color AND the word (never color alone). Printed once, immutable.
 */
export function renderToolLine(line: SettledToolLine, width: number, theme: Theme): string {
  let body: string;
  switch (line.outcome) {
    case "failed":
      body = theme.paint("error", line.summary);
      break;
    case "cancelled":
      body = `${line.summary}${theme.paint("dim", " · ")}${theme.paint("warning", "cancelled")}`;
      break;
    default:
      body = line.summary;
  }
  let text = ` ${glyphFor(line.kind, theme)} ${body}`;
  if (line.index !== undefined) {
    const tag = theme.paint("dim", `[${line.index}]`);
    const pad = Math.max(1, width - 2 - visibleWidth(text) - visibleWidth(tag));
    text += " ".repeat(pad) + tag;
  }
  return truncateAnsi(text, width);
}

export interface RunningToolRow {
  /** Verb + argument, e.g. `Run npm test`. */
  label: string;
  startedAt: number;
  /** Rolling output tail (already ANSI-stripped by the tool layer). */
  outputTail?: string[];
  /** Tool family — colors the `▸` glyph (dim when unknown). */
  kind?: ToolLineKind;
}

/** Live-region row for a running tool: label + real elapsed timer + optional tail. */
export function renderRunningTool(
  row: RunningToolRow,
  now: number,
  width: number,
  theme: Theme,
): string[] {
  const elapsed = Math.max(0, now - row.startedAt) / 1000;
  const secs = elapsed >= 10 ? `${Math.round(elapsed)}s` : `${elapsed.toFixed(1)}s`;
  const lines = [
    truncateAnsi(
      ` ${glyphFor(row.kind, theme)} ${row.label}${theme.paint("dim", ` · ${secs}`)}`,
      width,
    ),
  ];
  if (row.outputTail !== undefined) {
    for (const out of row.outputTail) {
      lines.push(truncateAnsi("   " + theme.paint("dim", out), width));
    }
  }
  return lines;
}

export interface ToolDetailBlock {
  index: number;
  /** The tool subject, e.g. `npm test`. */
  title: string;
  lines: string[];
  /** Real omitted-line count when output was truncated (§6.3). */
  omitted?: number;
  /** Spill file path for the full output (~/.khaelor/tool-out/<id>.txt). */
  spillFile?: string;
}

const DETAIL_BODY_CAP = 12;

/**
 * Post-hoc expansion prints detail as a NEW settled block — scrollback is
 * immutable, rows are never mutated retroactively (TUI_DESIGN §6.2).
 */
export function renderToolDetailBlock(
  block: ToolDetailBlock,
  width: number,
  theme: Theme,
): string[] {
  const out: string[] = [rule(` tool ${block.index} · ${block.title} `, width, theme)];
  const body = block.lines.slice(0, DETAIL_BODY_CAP);
  for (const line of body) out.push(truncateAnsi("  " + line, width));
  const hiddenHere = block.lines.length - body.length;
  const omitted = (block.omitted ?? 0) + hiddenHere;
  if (omitted > 0) {
    const spill = block.spillFile !== undefined ? ` · full output: ${block.spillFile}` : "";
    out.push(truncateAnsi(theme.paint("dim", `  … ${omitted} lines omitted${spill}`), width));
  }
  out.push(theme.paint("dim", "─".repeat(Math.max(10, Math.min(width - 1, 60)))));
  return out;
}

/** Section rule: `── label ────…` sized to width. */
export function rule(label: string, width: number, theme: Theme): string {
  const target = Math.max(10, Math.min(width - 1, 60));
  const head = `──${label}`;
  const tail = "─".repeat(Math.max(0, target - [...head].length));
  return theme.paint("dim", head + tail);
}