let test = require("tape");
let fs = require("fs");
let path = require("path");
let PNG = require("../lib/png").PNG;
let stream = require("stream");

function parseFile(filename, cb) {
  fs.createReadStream(path.join(__dirname, "png-parse-data", filename))
    .pipe(new PNG())
    .on("error", function (e) {
      console.log("error");
      cb(e);
    })
    .on("parsed", function () {
      cb(null, this);
    });
}

function parseBuffer(buffer, cb) {
  let bufferStream = new stream.PassThrough();
  bufferStream.end(buffer);

  bufferStream
    .pipe(new PNG({}))
    .on("error", function (e) {
      cb(e);
    })
    .on("parse", function () {
      cb(null, this);
    });
}

function getPixel(png, x, y) {
  return png.data.readUInt32BE((x + y * png.width) * 4);
}

test("should correctly parse an 1-bit colormap png", function (t) {
  t.timeoutAfter(5000);
  parseFile("1bit.png", function (err, png) {
    t.equal(err, null, "there should be no error");
    t.equal(png.width, 1024, "the width should be 1024");
    t.equal(png.height, 1024, "the height should be 1024");
    //t.equal(png.bpp, 1, "the bpp should be 1");
    t.equal(png.data.length, 1024 * 1024 * 4);
    //t.equal(png.trailer.length, 0);

    let y = 1024,
      x;

    let isOk = true;
    while (y--) {
      x = 1024;
      while (x--)
        if (getPixel(png, x, y) !== 0x000000ff) {
          t.fail(
            "pixel does not match - " + getPixel(png, x, y) + " !== 0x000000FF"
          );
          isOk = false;
          break;
        }
    }
    t.ok(isOk, "The pixels should all be black");

    t.end();
  });
});

test("should correctly parse an 8-bit grayscale png", function (t) {
  parseFile("grayscale.png", function (err, png) {
    t.equal(err, null);
    t.equal(png.width, 16);
    t.equal(png.height, 16);
    //t.equal(png.bpp, 1);
    t.equal(png.data.length, 16 * 16 * 4);
    //t.equal(png.trailer.toString(), "Hello, world!\n");

    let y = 16,
      x;

    let isOk = true;
    while (y--) {
      x = 16;
      while (x--) {
        if (getPixel(png, x, y) !== (x ^ y) * 286331136 + 255) {
          t.fail(
            "pixel does not match - " +
              getPixel(png, x, y) +
              " !== " +
              ((x ^ y) * 286331136 + 255)
          );
          isOk = false;
          break;
        }
      }
    }
    t.ok(isOk, "The pixels should match");

    t.end();
  });
});

test("should correctly parse an 8-bit truecolor png", function (t) {
  parseFile("truecolor.png", function (err, png) {
    t.equal(err, null);
    t.equal(png.width, 16);
    t.equal(png.height, 16);
    //t.equal(png.bpp, 3);
    t.equal(png.data.length, 16 * 16 * 4);
    //t.equal(png.trailer.length, 0);

    let y = 16,
      x;

    let isOk = true;
    while (y--) {
      x = 16;
      while (x--) {
        if (
          getPixel(png, x, y) !==
          x * 285212672 + y * 1114112 + (x ^ y) * 4352 + 255
        ) {
          t.fail(
            "pixel does not match - " +
              getPixel(png, x, y) +
              " !== " +
              (x * 285212672 + y * 1114112 + (x ^ y) * 4352 + 255)
          );
          isOk = false;
          break;
        }
      }
    }
    t.ok(isOk, "The pixels should match");

    t.end();
  });
});

test("should correctly parse an 8-bit truecolor png with alpha", function (t) {
  parseFile("truecoloralpha.png", function (err, png) {
    t.equal(err, null);
    t.equal(png.width, 16);
    t.equal(png.height, 16);
    //t.equal(png.bpp, 4);
    t.equal(png.data.length, 16 * 16 * 4);
    //t.equal(png.trailer.length, 0);

    let y = 16,
      x;
    let isOk = true;

    while (y--) {
      x = 16;
      while (x--) {
        if (
          getPixel(png, x, y) !==
          x * 285212672 + y * 1114112 + (x ^ y) * 17
        ) {
          t.fail(
            "pixel does not match - " +
              getPixel(png, x, y) +
              " !== " +
              (x * 285212672 + y * 1114112 + (x ^ y) * 17)
          );
          isOk = false;
          break;
        }
      }
    }
    t.ok(isOk, "The pixels should match");

    t.end();
  });
});

test("should correctly read image with scanline filter", function (t) {
  parseFile("accum.png", function (err, png) {
    t.equal(err, null);
    t.equal(png.width, 1024);
    t.equal(png.height, 1024);
    //t.equal(png.bpp, 3);
    t.equal(png.data.length, 1024 * 1024 * 4);
    //t.equal(png.trailer.length, 0);

    t.equal(getPixel(png, 0, 0), 0xff0000ff);
    t.equal(getPixel(png, 1, 0), 0xff0000ff);
    t.equal(getPixel(png, 420, 308), 0xff0029ff);
    t.equal(getPixel(png, 433, 308), 0x0a299dff);
    t.equal(getPixel(png, 513, 308), 0x0066ffff);
    t.equal(getPixel(png, 728, 552), 0xff0047ff);

    t.end();
  });
});

test("should correctly read an indexed color image", function (t) {
  parseFile("indexed.png", function (err, png) {
    t.equal(err, null);
    t.equal(png.width, 16);
    t.equal(png.height, 16);
    //t.equal(png.bpp, 3);
    t.equal(png.data.length, 16 * 16 * 4);
    //t.equal(png.trailer.length, 0);

    let y = 16,
      x;
    let isOk = true;

    while (y--) {
      x = 16;
      while (x--) {
        let expected;
        if (x + y < 8) {
          expected = 0xff0000ff;
        } else if (x + y < 16) {
          expected = 0x00ff00ff;
        } else if (x + y < 24) {
          expected = 0x0000ffff;
        } else {
          expected = 0x000000ff;
        }

        if (getPixel(png, x, y) !== expected) {
          t.fail(
            "pixel does not match - " + getPixel(png, x, y) + " !== " + expected
          );
          isOk = false;
          break;
        }
      }
    }
    t.ok(isOk, "The pixels should match");
    t.end();
  });
});

test("should correctly read an indexed color image with alpha", function (t) {
  parseFile("indexedalpha.png", function (err, png) {
    t.equal(err, null);
    t.equal(png.width, 16);
    t.equal(png.height, 16);
    //t.equal(png.bpp, 4);
    t.equal(png.data.length, 16 * 16 * 4);
    //t.equal(png.trailer.length, 0);

    let y = 16,
      x;
    let isOk = true;

    while (y--) {
      x = 16;
      while (x--) {
        let expected;
        if (x >= 4 && x < 12) {
          expected = 0x00000000;
        } else if (x + y < 8) {
          expected = 0xff0000ff;
        } else if (x + y < 16) {
          expected = 0x00ff00ff;
        } else if (x + y < 24) {
          expected = 0x0000ffff;
        } else {
          expected = 0x000000ff;
        }

        if (getPixel(png, x, y) !== expected) {
          t.fail(
            "pixel does not match - " + getPixel(png, x, y) + " !== " + expected
          );
          isOk = false;
          break;
        }
      }
    }
    t.ok(isOk, "The pixels should match");

    t.end();
  });
});

test("should correctly support crazily-filtered images", function (t) {
  parseFile("paeth.png", function (err, png) {
    t.equal(err, null);
    t.equal(png.width, 512);
    t.equal(png.height, 512);
    //t.equal(png.bpp, 4);
    t.equal(png.data.length, 512 * 512 * 4);

    t.equal(getPixel(png, 0, 0), 0xff000000);
    t.equal(getPixel(png, 1, 0), 0xff000000);
    t.equal(getPixel(png, 0, 1), 0xff000000);
    t.equal(getPixel(png, 2, 2), 0xff000000);
    t.equal(getPixel(png, 0, 50), 0xff000000);
    t.equal(getPixel(png, 219, 248), 0xff000d00);
    t.equal(getPixel(png, 220, 248), 0xff000d00);
    t.equal(getPixel(png, 215, 249), 0xff000c00);
    t.equal(getPixel(png, 216, 249), 0xff000c00);
    t.equal(getPixel(png, 217, 249), 0xff000d00);
    t.equal(getPixel(png, 218, 249), 0xff000d00);
    t.equal(getPixel(png, 219, 249), 0xff000e00);
    t.equal(getPixel(png, 220, 249), 0xff000e00);
    t.equal(getPixel(png, 263, 319), 0xff002100);
    t.equal(getPixel(png, 145, 318), 0x05535a00);
    t.equal(getPixel(png, 395, 286), 0x0007ff00);
    t.equal(getPixel(png, 152, 167), 0x052c3500);
    t.equal(getPixel(png, 153, 167), 0x04303600);
    t.equal(getPixel(png, 154, 167), 0x042f3700);
    t.equal(getPixel(png, 100, 168), 0xff000400);
    t.equal(getPixel(png, 120, 168), 0xff000900);
    t.equal(getPixel(png, 140, 168), 0xff001b00);
    t.equal(getPixel(png, 150, 168), 0x05313600);
    t.equal(getPixel(png, 152, 168), 0x04343c00);
    t.equal(getPixel(png, 153, 168), 0x03343f00);
    t.equal(getPixel(png, 154, 168), 0x03344100);
    t.equal(getPixel(png, 155, 168), 0x02344300);
    t.equal(getPixel(png, 156, 168), 0x02314400);
    t.equal(getPixel(png, 157, 168), 0x02323f00);
    t.equal(getPixel(png, 158, 168), 0x03313900);

    t.end();
  });
});

test("should bail with an error given an invalid PNG", function (t) {
  let buf = Buffer.from("I AM NOT ACTUALLY A PNG", "utf8");

  return parseBuffer(buf, function (err) {
    t.ok(err instanceof Error, "Error should be received");
    t.end();
  });
});

test("should bail with an error given an empty file", function (t) {
  let buf = Buffer.from("");

  return parseBuffer(buf, function (err) {
    t.ok(err instanceof Error, "Error should be received");
    t.end();
  });
});

test("should bail with an error given a truncated PNG", function (t) {
  let buf = Buffer.from("89504e470d0a1a0a000000", "hex");

  return parseBuffer(buf, function (err) {
    t.ok(err instanceof Error, "Error should be received");
    t.end();
  });
});

test("should return an error if a PNG is normal except for a missing IEND", function (t) {
  let buf = Buffer.from(
    "89504e470d0a1a0a0000000d49484452000000100000001008000000003a98a0bd000000017352474200aece1ce90000002174455874536f6674776172650047726170686963436f6e7665727465722028496e74656c297787fa190000008849444154789c448e4111c020100363010b58c00216b080052c60010b58c0c259c00216ae4d3b69df99dd0d1062caa5b63ee6b27d1c012996dceae86b6ef38398106acb65ae3e8edbbef780564b5e73743fdb409e1ef2f4803c3de4e901797ac8d3f3f0f490a7077ffffd03f5f507eaeb0fd4d71fa8af3f505f7fa0befe7c7dfdb9000000ffff0300c0fd7f8179301408",
    "hex"
  );

  return parseBuffer(buf, function (err) {
    t.ok(err instanceof Error, "Error should be received");
    t.end();
  });
});

test("should set alpha=true in metadata for images with tRNS chunk", function (t) {
  fs.createReadStream(path.join(__dirname, "in", "tbbn0g04.png"))
    .pipe(new PNG())
    .on("metadata", function (metadata) {
      t.ok(metadata.alpha, "Image should have alpha=true");
      t.end();
    });
});

test("Should parse with low highWaterMark", function (t) {
  fs.createReadStream(path.join(__dirname, "in", "tbbn0g04.png"), {
    highWaterMark: 2,
  })
    .pipe(new PNG())
    .on("parsed", function () {
      t.pass("Image should have parsed");
      t.end();
    })
    .on("error", function (e) {
      t.error(e, "Should not error");
    });
});