/*
 * Copyright (C) 2021 pedroSG94.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.pedro.encoder.input.gl.render.filters;

import android.content.Context;
import android.opengl.GLES20;
import android.opengl.Matrix;
import android.os.Build;
import androidx.annotation.RequiresApi;
import com.pedro.encoder.R;
import com.pedro.encoder.input.video.CameraHelper;
import com.pedro.encoder.utils.gl.GlUtil;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;

/**
 * Created by pedro on 9/07/18.
 */

@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR2)
public class RotationFilterRender extends BaseFilterRender {

  //rotation matrix
  private final float[] squareVertexDataFilter = {
      // X, Y, Z, U, V
      -1f, -1f, 0f, 0f, 0f, //bottom left
      1f, -1f, 0f, 1f, 0f, //bottom right
      -1f, 1f, 0f, 0f, 1f, //top left
      1f, 1f, 0f, 1f, 1f, //top right
  };

  private int program = -1;
  private int aPositionHandle = -1;
  private int aTextureHandle = -1;
  private int uMVPMatrixHandle = -1;
  private int uSTMatrixHandle = -1;
  private int uSamplerHandle = -1;

  private int rotation = 0;
  private float[] rotationMatrix = new float[16];

  public RotationFilterRender() {
    squareVertex = ByteBuffer.allocateDirect(squareVertexDataFilter.length * FLOAT_SIZE_BYTES)
        .order(ByteOrder.nativeOrder())
        .asFloatBuffer();
    squareVertex.put(squareVertexDataFilter).position(0);
    Matrix.setIdentityM(MVPMatrix, 0);
    Matrix.setIdentityM(STMatrix, 0);
    Matrix.setIdentityM(rotationMatrix, 0);
  }

  @Override
  protected void initGlFilter(Context context) {
    String vertexShader = GlUtil.getStringFromRaw(context, R.raw.simple_vertex);
    String fragmentShader = GlUtil.getStringFromRaw(context, R.raw.simple_fragment);

    program = GlUtil.createProgram(vertexShader, fragmentShader);
    aPositionHandle = GLES20.glGetAttribLocation(program, "aPosition");
    aTextureHandle = GLES20.glGetAttribLocation(program, "aTextureCoord");
    uMVPMatrixHandle = GLES20.glGetUniformLocation(program, "uMVPMatrix");
    uSTMatrixHandle = GLES20.glGetUniformLocation(program, "uSTMatrix");
    uSamplerHandle = GLES20.glGetUniformLocation(program, "uSampler");
  }

  @Override
  protected void drawFilter() {
    GLES20.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
    GLES20.glClear(GLES20.GL_DEPTH_BUFFER_BIT | GLES20.GL_COLOR_BUFFER_BIT);

    GLES20.glUseProgram(program);

    squareVertex.position(SQUARE_VERTEX_DATA_POS_OFFSET);
    GLES20.glVertexAttribPointer(aPositionHandle, 3, GLES20.GL_FLOAT, false,
        SQUARE_VERTEX_DATA_STRIDE_BYTES, squareVertex);
    GLES20.glEnableVertexAttribArray(aPositionHandle);

    squareVertex.position(SQUARE_VERTEX_DATA_UV_OFFSET);
    GLES20.glVertexAttribPointer(aTextureHandle, 2, GLES20.GL_FLOAT, false,
        SQUARE_VERTEX_DATA_STRIDE_BYTES, squareVertex);
    GLES20.glEnableVertexAttribArray(aTextureHandle);

    GLES20.glUniformMatrix4fv(uMVPMatrixHandle, 1, false, MVPMatrix, 0);
    GLES20.glUniformMatrix4fv(uSTMatrixHandle, 1, false, STMatrix, 0);

    GLES20.glUniform1i(uSamplerHandle, 4);
    GLES20.glActiveTexture(GLES20.GL_TEXTURE4);
    GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, previousTexId);
  }

  @Override
  public void release() {
    GLES20.glDeleteProgram(program);
  }

  public int getRotation() {
    return rotation;
  }

  public void setRotation(int rotation) {
    this.rotation = rotation;
    //Set rotation
    Matrix.setRotateM(rotationMatrix, 0, rotation, 0, 0, 1.0f);
    Matrix.scaleM(rotationMatrix, 0, 1f, 1f, 0f);
    //Translation
    //Matrix.translateM(rotationMatrix, 0, 0f, 0f, 0f);
    // Combine the rotation matrix with the projection and camera view
    Matrix.multiplyMM(MVPMatrix, 0, rotationMatrix, 0, MVPMatrix, 0);
  }

  /**
   * Keep aspect ratio if you rotate 90º or 270º.
   * @param rotation value
   * @param width width of stream (prepareVideo method) if you are streaming or preview (startPreview method) if you aren't streaming.
   * @param height height of stream (prepareVideo method) if you are streaming or preview (startPreview method) if you aren't streaming.
   */
  public void setRotationFixed(int rotation, int width, int height, boolean isPortrait) {
    this.rotation = rotation;
    //Set rotation
    Matrix.setRotateM(rotationMatrix, 0, rotation, 0, 0, 1.0f);
    if (rotation == 90 || rotation == 270) {
      float value = (float) height / (float) width;
      if (isPortrait) {
        Matrix.scaleM(rotationMatrix, 0, value, 1f, 0f);
      } else {
        Matrix.scaleM(rotationMatrix, 0, 1f, value, 0f);
      }
    } else {
      Matrix.scaleM(rotationMatrix, 0, 1f, 1f, 0f);
    }
    // Combine the rotation matrix with the projection and camera view
    Matrix.multiplyMM(MVPMatrix, 0, rotationMatrix, 0, MVPMatrix, 0);
  }
}