import { assert, assertEquals } from "@std/assert";
import { existsSync } from "node:fs";
import { withDom } from "@berry/util/dom.ts";
import { Grid } from "./grid.ts";
import { Ghostty } from "./ghostty.ts";

Deno.test("rescaling the grid repaints cached cells without replacing selected text", async () => {
  await withDom((window) => {
    const rows = document.createElement("div");
    const canvas = document.createElement("canvas");
    const painted: number[][] = [];
    Object.defineProperty(canvas, "getContext", {
      value: () => ({
        clearRect: () => painted.splice(0),
        fillRect: (...rect: number[]) => painted.push(rect),
      }),
    });
    const grid = new Grid(rows, canvas);
    const metrics = { width: 200, height: 100, ratio: 1, cell: { width: 8.25, height: 18.5 } };
    grid.fit(metrics);
    const bg = [61, 34, 74] as const;
    grid.update({
      cols: 20,
      rows: 2,
      cursor: null,
      changed: new Map([
        [0, [{ text: "e\u0301", bg }, { text: "🦀", bg, wide: true }, { text: "x", bg }]],
        [1, [{ text: "next", bg }]],
      ]),
    });
    assertEquals(rows.firstChild!.textContent, "e\u0301🦀x");
    const range = window.document.createRange();
    const text = rows.firstChild!.firstChild!.firstChild!;
    range.selectNodeContents(text as unknown as Parameters<typeof range.selectNodeContents>[0]);
    window.getSelection().addRange(range);

    for (const ratio of [1, 1.25, 1.5, 2, 0.8]) {
      grid.fit({ ...metrics, ratio });
      assertEquals(window.getSelection().toString(), "e\u0301");
      assertEquals(rows.firstChild!.firstChild!.firstChild, text);
      assertEquals(painted.length, 4);
      const [first, wide, last, next] = painted;
      assertEquals(first[0], 0);
      assertEquals(first[0] + first[2], wide[0]);
      assertEquals(wide[0] + wide[2], last[0]);
      assertEquals(first[1] + first[3], next[1]);
      assertEquals(last[0] + last[2], next[2]);
      assert(wide[2] > first[2]);
      assert(painted.flat().every(Number.isInteger));
    }

    grid.update({ cols: 20, rows: 2, cursor: null, changed: new Map() });
    assertEquals(painted.length, 4);
    assertEquals(rows.firstChild!.firstChild!.firstChild, text);
  });
});

Deno.test({
  name: "screen-filling backgrounds include blank cells through the screen edges",
  ignore: !existsSync(new URL("./ghostty-vt.wasm", import.meta.url)),
  async fn() {
    const ghostty = await Ghostty.load(
      await Deno.readFile(new URL("./ghostty-vt.wasm", import.meta.url)),
    );
    const terminal = ghostty.terminal(20, 4);
    try {
      terminal.write(new TextEncoder().encode(
        "\x1b[?25l\x1b[48;2;61;34;74m" + " ".repeat(80) + "\x1b[Hé🦀x",
      ));
      const frame = terminal.frame();
      await withDom(() => {
        const canvas = document.createElement("canvas");
        const painted: number[][] = [];
        Object.defineProperty(canvas, "getContext", {
          value: () => ({
            clearRect: () => painted.splice(0),
            fillRect: (...rect: number[]) => painted.push(rect),
          }),
        });
        const grid = new Grid(document.createElement("div"), canvas);
        grid.fit({ width: 165, height: 74, ratio: 1.25, cell: { width: 8.25, height: 18.5 } });
        grid.update(frame);
        assertEquals(
          painted.reduce((area, [, , width, height]) => area + width * height, 0),
          canvas.width * canvas.height,
        );
        assertEquals(Math.max(...painted.map(([x, , width]) => x + width)), canvas.width);
        assertEquals(Math.max(...painted.map(([, y, , height]) => y + height)), canvas.height);
      });
    } finally {
      terminal.free();
    }
  },
});