import type { Theme } from "@oh-my-pi/pi-coding-agent";
import { type Component, matchesKey, replaceTabs, Text, truncateToWidth } from "@oh-my-pi/pi-tui";
import copy from "./copy.json";
import type { ReviewAction } from "./domain";

// Untrusted note text is data, never terminal control or ANSI styling.
export function safeText(text: string): string {
  return replaceTabs(Bun.stripANSI(text)).replace(/[\u0000-\u0008\u000b-\u001f\u007f-\u009f\u202a-\u202e\u2066-\u2069]/g, "");
}

export class BoundedText implements Component {
  private readonly text: Text;
  constructor(content: string, theme?: Theme) {
    this.text = new Text(safeText(content), 0, 0);
    if (theme) this.text.setStyleFn(line => theme.fg("text", line));
  }
  invalidate(): void { this.text.invalidate(); }
  render(width: number): readonly string[] {
    const columns = Math.max(0, Math.min(100, Math.floor(width)));
    if (columns === 0) return [];
    return this.text.render(columns).map(line => truncateToWidth(line, columns, ""));
  }
}

export class ReviewPanel implements Component {
  private readonly title: BoundedText;
  private readonly body: BoundedText;
  private readonly keys: BoundedText;
  private offset = 0;
  private maxOffset = 0;
  private disposed = false;

  constructor(text: string, theme: Theme, private readonly redraw: () => void,
    private readonly done: (action: Exclude<ReviewAction, "revise">) => void) {
    this.title = new BoundedText(copy.panelTitle, theme);
    this.body = new BoundedText(text, theme);
    this.keys = new BoundedText(`${copy.panelKeys}\n${copy.panelEnd}`, theme);
  }

  invalidate(): void {
    this.title.invalidate();
    this.body.invalidate();
    this.keys.invalidate();
  }

  render(width: number): readonly string[] {
    if (this.disposed || width < 1) return [];
    const body = this.body.render(width);
    this.maxOffset = Math.max(0, body.length - 8);
    this.offset = Math.min(this.offset, this.maxOffset);
    return [...this.title.render(width), ...body.slice(this.offset, this.offset + 8), ...this.keys.render(width)];
  }

  handleInput(data: string): void {
    if (this.disposed) return;
    if (matchesKey(data, "escape")) this.finish("cancel");
    else if (data === "a") this.finish("accept");
    else if (data === "r") this.finish("reject");
    else if (matchesKey(data, "up") || matchesKey(data, "down")) {
      this.offset = Math.max(0, Math.min(this.maxOffset, this.offset + (matchesKey(data, "up") ? -1 : 1)));
      this.redraw();
    }
  }

  private finish(action: Exclude<ReviewAction, "revise">): void {
    this.dispose();
    this.done(action);
  }

  dispose(): void { this.disposed = true; }
}