/**
 * Formats multi-line dialog messages for readable terminal display.
 *
 * Ink's `wrap="wrap"` breaks long lines mid-word, which looks broken for
 * dot-separated template validation paths. We pre-split on newlines and break
 * long lines at `.` segment boundaries instead.
 */

/**
 * Hard-wraps text when a single segment still exceeds the maximum width.
 */
function hardWrapLine(line: string, maxWidth: number): string[] {
  if (line.length <= maxWidth) {
    return [line];
  }

  const wrapped: string[] = [];
  let remaining = line;

  while (remaining.length > maxWidth) {
    wrapped.push(remaining.slice(0, maxWidth));
    remaining = `  ${remaining.slice(maxWidth)}`;
  }

  if (remaining.length > 0) {
    wrapped.push(remaining);
  }

  return wrapped;
}

/**
 * Breaks a long line at dot-separated segments, indenting continuations.
 */
function breakLongLineAtDots(line: string, maxWidth: number): string[] {
  const segments: string[] = [];
  let segmentStart = 0;

  for (let index = 0; index < line.length; index += 1) {
    if (line[index] === "." && index > 0) {
      segments.push(line.slice(segmentStart, index + 1));
      segmentStart = index + 1;
    }
  }

  if (segmentStart < line.length) {
    segments.push(line.slice(segmentStart));
  }

  if (segments.length === 0) {
    return hardWrapLine(line, maxWidth);
  }

  const lines: string[] = [];
  let current = "";

  for (const segment of segments) {
    const candidate = current + segment;

    if (candidate.length > maxWidth && current.length > 0) {
      lines.push(current);
      current = `  ${segment}`;
      continue;
    }

    if (candidate.length > maxWidth) {
      lines.push(...hardWrapLine(segment, maxWidth));
      current = "";
      continue;
    }

    current = candidate;
  }

  if (current.length > 0) {
    lines.push(current);
  }

  return lines;
}

/**
 * Splits a dialog message into display lines that fit the available width.
 */
export function formatDialogMessageLines(
  message: string,
  contentWidth: number,
): string[] {
  const output: string[] = [];

  for (const rawLine of message.split("\n")) {
    const line = rawLine.trimEnd();
    if (line.length === 0) {
      continue;
    }

    if (line.length <= contentWidth) {
      output.push(line);
      continue;
    }

    output.push(...breakLongLineAtDots(line, contentWidth));
  }

  return output;
}

/**
 * Computes dialog width from the terminal size.
 */
export function getMessageDialogWidth(terminalColumns: number): number {
  return Math.min(Math.max(terminalColumns - 4, 60), 100);
}

/** Inner text width after dialog border and horizontal padding. */
export function getMessageContentWidth(dialogWidth: number): number {
  return Math.max(dialogWidth - 6, 40);
}

/** Maximum number of body lines shown before truncating with a summary. */
export const MAX_MESSAGE_DIALOG_LINES = 24;