/**
 *
 */
package org.nativescript.widgets;

import android.annotation.SuppressLint;
import android.content.Context;
import android.content.pm.ApplicationInfo;
import android.content.pm.PackageManager.NameNotFoundException;
import android.util.Log;
import android.view.Gravity;
import android.view.View;
import android.view.View.MeasureSpec;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.widget.FrameLayout;

/**
 * @author hhristov
 */
public class CommonLayoutParams extends FrameLayout.LayoutParams {

	static final String TAG = "NSLayout";
	static int debuggable = -1;
	private static final int NOT_SET = Integer.MIN_VALUE;
	private static StringBuilder debugSb = null;

	public CommonLayoutParams() {
		super(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT, Gravity.FILL);
	}

	public CommonLayoutParams(ViewGroup.LayoutParams source) {
		super(source);
	}

	public CommonLayoutParams(ViewGroup.MarginLayoutParams source) {
		super(source);
	}

	public CommonLayoutParams(FrameLayout.LayoutParams source) {
		super((ViewGroup.MarginLayoutParams) source);
		this.gravity = source.gravity;
	}

	public CommonLayoutParams(CommonLayoutParams source) {
		this((FrameLayout.LayoutParams) source);

		this.widthPercent = source.widthPercent;
		this.heightPercent = source.heightPercent;

		this.topMargin = source.topMargin;
		this.leftMargin = source.leftMargin;
		this.bottomMargin = source.bottomMargin;
		this.rightMargin = source.rightMargin;

		this.left = source.left;
		this.top = source.top;
		this.row = source.row;
		this.column = source.column;
		this.rowSpan = source.rowSpan;
		this.columnSpan = source.columnSpan;
		this.dock = source.dock;
	}

	public float widthPercent = 0;
	public float heightPercent = 0;

	public float topMarginPercent = 0;
	public float leftMarginPercent = 0;
	public float bottomMarginPercent = 0;
	public float rightMarginPercent = 0;

	public int widthOriginal = NOT_SET;
	public int heightOriginal = NOT_SET;

	public int topMarginOriginal = NOT_SET;
	public int leftMarginOriginal = NOT_SET;
	public int bottomMarginOriginal = NOT_SET;
	public int rightMarginOriginal = NOT_SET;

	public int left = 0;
	public int top = 0;
	public int row = 0;
	public int column = 0;
	public int rowSpan = 1;
	public int columnSpan = 1;
	public Dock dock = Dock.left;

	protected static int getDesiredWidth(View view) {
		CommonLayoutParams lp = (CommonLayoutParams) view.getLayoutParams();
		return view.getMeasuredWidth() + lp.leftMargin + lp.rightMargin;
	}

	protected static int getDesiredHeight(View view) {
		CommonLayoutParams lp = (CommonLayoutParams) view.getLayoutParams();
		return view.getMeasuredHeight() + lp.topMargin + lp.bottomMargin;
	}

	// We use our own layout method because the one in FrameLayout is broken when margins are set and gravity is CENTER_VERTICAL or CENTER_HORIZONTAL.
	@SuppressLint("RtlHardcoded")
	protected static void layoutChild(View child, int left, int top, int right, int bottom) {
		if (child == null || child.getVisibility() == View.GONE) {
			return;
		}

		int childTop = 0;
		int childLeft = 0;

		int childWidth = child.getMeasuredWidth();
		int childHeight = child.getMeasuredHeight();

		CommonLayoutParams lp = (CommonLayoutParams) child.getLayoutParams();
		int gravity = lp.gravity;
		if (gravity == -1) {
			gravity = Gravity.FILL;
		}

		int verticalGravity = gravity & Gravity.VERTICAL_GRAVITY_MASK;

		// If we have explicit height and gravity is FILL we need to be centered otherwise our explicit height won't be taken into account.
		if ((lp.height >= 0 || lp.heightPercent > 0) && verticalGravity == Gravity.FILL_VERTICAL) {
			verticalGravity = Gravity.CENTER_VERTICAL;
		}

		switch (verticalGravity) {
			case Gravity.TOP:
				childTop = top + lp.topMargin;
				break;

			case Gravity.CENTER_VERTICAL:
				childTop = top + (bottom - top - childHeight + lp.topMargin - lp.bottomMargin) / 2;
				break;

			case Gravity.BOTTOM:
				childTop = bottom - childHeight - lp.bottomMargin;
				break;

			case Gravity.FILL_VERTICAL:
			default:
				childTop = top + lp.topMargin;
				childHeight = bottom - top - (lp.topMargin + lp.bottomMargin);
				break;
		}

		int horizontalGravity = Gravity.getAbsoluteGravity(gravity, child.getLayoutDirection()) & Gravity.HORIZONTAL_GRAVITY_MASK;

		// If we have explicit width and gravity is FILL we need to be centered otherwise our explicit width won't be taken into account.
		if ((lp.width >= 0 || lp.widthPercent > 0) && horizontalGravity == Gravity.FILL_HORIZONTAL) {
			horizontalGravity = Gravity.CENTER_HORIZONTAL;
		}

		switch (horizontalGravity) {
			case Gravity.LEFT:
				childLeft = left + lp.leftMargin;
				break;

			case Gravity.CENTER_HORIZONTAL:
				childLeft = left + (right - left - childWidth + lp.leftMargin - lp.rightMargin) / 2;
				break;

			case Gravity.RIGHT:
				childLeft = right - childWidth - lp.rightMargin;
				break;

			case Gravity.FILL_HORIZONTAL:
			default:
				childLeft = left + lp.leftMargin;
				childWidth = right - left - (lp.leftMargin + lp.rightMargin);
				break;
		}

		int childRight = Math.round(childLeft + childWidth);
		int childBottom = Math.round(childTop + childHeight);
		childLeft = Math.round(childLeft);
		childTop = Math.round(childTop);

		// Re-measure TextView because it is not centered if layout width is larger than measure width.
		if (child instanceof android.widget.TextView) {

			boolean canChangeWidth = lp.width < 0;
			boolean canChangeHeight = lp.height < 0;

			int measuredWidth = child.getMeasuredWidth();
			int measuredHeight = child.getMeasuredHeight();

			int width = childRight - childLeft;
			int height = childBottom - childTop;
			if ((Math.abs(measuredWidth - width) > 1 && canChangeWidth) || (Math.abs(measuredHeight - height) > 1 && canChangeHeight)) {
				int widthMeasureSpec = MeasureSpec.makeMeasureSpec(canChangeWidth ? width : lp.width, MeasureSpec.EXACTLY);
				int heightMeasureSpec = MeasureSpec.makeMeasureSpec(canChangeHeight ? height : lp.height, MeasureSpec.EXACTLY);
				if (debuggable > 0) {
					debugSb.setLength(0);
					debugSb.append("remeasure ");
					debugSb.append(child);
					debugSb.append(" with ");
					debugSb.append(MeasureSpec.toString(widthMeasureSpec));
					debugSb.append(", ");
					debugSb.append(MeasureSpec.toString(heightMeasureSpec));
					Log.v(TAG, debugSb.toString());
				}

				child.measure(widthMeasureSpec, heightMeasureSpec);
			}
		}

		if (debuggable > 0) {
			debugSb.setLength(0);
			debugSb.append(child.getParent().toString());
			debugSb.append(" :layoutChild: ");
			debugSb.append(child);
			debugSb.append(" ");
			debugSb.append(childLeft);
			debugSb.append(", ");
			debugSb.append(childTop);
			debugSb.append(", ");
			debugSb.append(childRight);
			debugSb.append(", ");
			debugSb.append(childBottom);
			Log.v(TAG, debugSb.toString());
		}

		child.layout(childLeft, childTop, childRight, childBottom);
	}

	protected static void measureChild(View child, int widthMeasureSpec, int heightMeasureSpec) {
		if (child == null || child.getVisibility() == View.GONE) {
			return;
		}

		// TODO: do we really need that code?
		// Negative means not initialized.
		if (debuggable < 0) {
			try {
				Context context = child.getContext();
				ApplicationInfo ai = context.getPackageManager().getApplicationInfo(context.getPackageName(), android.content.pm.PackageManager.GET_META_DATA);
				android.os.Bundle bundle = ai.metaData;
				Boolean debugLayouts = bundle != null && bundle.getBoolean("debugLayouts", false);
				debuggable = debugLayouts ? 1 : 0;
				if (debuggable == 1) {
					CommonLayoutParams.debugSb = new StringBuilder();
				}
			} catch (NameNotFoundException e) {
				debuggable = 0;
				Log.e(TAG, "Failed to load meta-data, NameNotFound: " + e.getMessage());
			} catch (NullPointerException e) {
				debuggable = 0;
				Log.e(TAG, "Failed to load meta-data, NullPointer: " + e.getMessage());
			}
		}

		int childWidthMeasureSpec = getMeasureSpec(child, widthMeasureSpec, true);
		int childHeightMeasureSpec = getMeasureSpec(child, heightMeasureSpec, false);

		if (debuggable > 0) {
			debugSb.setLength(0);
			debugSb.append(child.getParent().toString());
			debugSb.append(" :measureChild: ");
			debugSb.append(child);
			debugSb.append(" ");
			debugSb.append(MeasureSpec.toString(childWidthMeasureSpec));
			debugSb.append(", ");
			debugSb.append(MeasureSpec.toString(childHeightMeasureSpec));
			Log.v(TAG, debugSb.toString());
		}

		child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
	}

	/**
	 * Iterates over children and changes their width and height to one calculated from percentage
	 * values.
	 *
	 * @param viewGroup         The parent ViewGroup.
	 * @param widthMeasureSpec  Width MeasureSpec of the parent ViewGroup.
	 * @param heightMeasureSpec Height MeasureSpec of the parent ViewGroup.
	 */
	protected static void adjustChildrenLayoutParams(ViewGroup viewGroup, int widthMeasureSpec, int heightMeasureSpec) {

		int availableWidth = MeasureSpec.getSize(widthMeasureSpec);
		int widthSpec = MeasureSpec.getMode(widthMeasureSpec);

		int availableHeight = MeasureSpec.getSize(heightMeasureSpec);
		int heightSpec = MeasureSpec.getMode(heightMeasureSpec);

		for (int i = 0, count = viewGroup.getChildCount(); i < count; i++) {
			View child = viewGroup.getChildAt(i);
			LayoutParams params = child.getLayoutParams();

			if (params instanceof CommonLayoutParams) {
				CommonLayoutParams lp = (CommonLayoutParams) child.getLayoutParams();
				if (widthSpec != MeasureSpec.UNSPECIFIED) {
					if (lp.widthPercent > 0) {
						// If we get measured twice we will override the original value with the one calculated from percentValue from the first measure.
						// So we set originalValue only the first time.
						if (lp.widthOriginal == NOT_SET) {
							lp.widthOriginal = lp.width;
						}
						lp.width = (int) (availableWidth * lp.widthPercent);
					} else {
						lp.widthOriginal = NOT_SET;
					}

					if (lp.leftMarginPercent > 0) {
						if (lp.leftMarginOriginal == NOT_SET) {
							lp.leftMarginOriginal = lp.leftMargin;
						}
						lp.leftMargin = (int) (availableWidth * lp.leftMarginPercent);
					} else {
						lp.leftMarginOriginal = NOT_SET;
					}

					if (lp.rightMarginPercent > 0) {
						if (lp.rightMarginOriginal == NOT_SET) {
							lp.rightMarginOriginal = lp.rightMargin;
						}
						lp.rightMargin = (int) (availableWidth * lp.rightMarginPercent);
					} else {
						lp.rightMarginOriginal = NOT_SET;
					}
				}

				if (heightSpec != MeasureSpec.UNSPECIFIED) {
					if (lp.heightPercent > 0) {
						if (lp.heightOriginal == NOT_SET) {
							lp.heightOriginal = lp.height;
						}
						lp.height = (int) (availableHeight * lp.heightPercent);
					} else {
						lp.heightOriginal = NOT_SET;
					}

					if (lp.topMarginPercent > 0) {
						if (lp.topMarginOriginal == NOT_SET) {
							lp.topMarginOriginal = lp.topMargin;
						}
						lp.topMargin = (int) (availableHeight * lp.topMarginPercent);
					} else {
						lp.topMarginOriginal = NOT_SET;
					}

					if (lp.bottomMarginPercent > 0) {
						if (lp.bottomMarginOriginal == NOT_SET) {
							lp.bottomMarginOriginal = lp.bottomMargin;
						}
						lp.bottomMargin = (int) (availableHeight * lp.bottomMarginPercent);
					} else {
						lp.bottomMarginOriginal = NOT_SET;
					}
				}
			}
		}
	}

	/**
	 * Iterates over children and restores their original dimensions that were changed for
	 * percentage values.
	 */
	protected static void restoreOriginalParams(ViewGroup viewGroup) {
		for (int i = 0, count = viewGroup.getChildCount(); i < count; i++) {
			View view = viewGroup.getChildAt(i);
			LayoutParams params = view.getLayoutParams();
			if (params instanceof CommonLayoutParams) {
				CommonLayoutParams lp = (CommonLayoutParams) params;
				if (lp.widthPercent > 0) {
					lp.width = lp.widthOriginal;
				}
				if (lp.heightPercent > 0) {
					lp.height = lp.heightOriginal;
				}
				if (lp.leftMarginPercent > 0) {
					lp.leftMargin = lp.leftMarginOriginal;
				}
				if (lp.topMarginPercent > 0) {
					lp.topMargin = lp.topMarginOriginal;
				}
				if (lp.rightMarginPercent > 0) {
					lp.rightMargin = lp.rightMarginOriginal;
				}
				if (lp.bottomMarginPercent > 0) {
					lp.bottomMargin = lp.bottomMarginOriginal;
				}

				lp.widthOriginal = NOT_SET;
				lp.heightOriginal = NOT_SET;
				lp.leftMarginOriginal = NOT_SET;
				lp.topMarginOriginal = NOT_SET;
				lp.rightMarginOriginal = NOT_SET;
				lp.bottomMarginOriginal = NOT_SET;
			}
		}
	}

	static StringBuilder getStringBuilder() {
		debugSb.setLength(0);
		return debugSb;
	}

	private static int getMeasureSpec(View view, int parentMeasureSpec, boolean horizontal) {

		int parentLength = MeasureSpec.getSize(parentMeasureSpec);
		int parentSpecMode = MeasureSpec.getMode(parentMeasureSpec);

		CommonLayoutParams lp = (CommonLayoutParams) view.getLayoutParams();
		final int margins = horizontal ? lp.leftMargin + lp.rightMargin : lp.topMargin + lp.bottomMargin;

		int resultSize = 0;
		int resultMode = MeasureSpec.UNSPECIFIED;

		int measureLength = Math.max(0, parentLength - margins);
		int childLength = horizontal ? lp.width : lp.height;

		// We want a specific size... let be it.
		if (childLength >= 0) {
			if (parentSpecMode != MeasureSpec.UNSPECIFIED) {
				resultSize = Math.min(parentLength, childLength);
			} else {
				resultSize = childLength;
			}

			resultMode = MeasureSpec.EXACTLY;
		} else {
			switch (parentSpecMode) {
				// Parent has imposed an exact size on us
				case MeasureSpec.EXACTLY:
					resultSize = measureLength;
					int gravity = LayoutBase.getGravity(view);
					boolean stretched;
					if (horizontal) {
						final int horizontalGravity = Gravity.getAbsoluteGravity(gravity, view.getLayoutDirection()) & Gravity.HORIZONTAL_GRAVITY_MASK;
						stretched = horizontalGravity == Gravity.FILL_HORIZONTAL;
					} else {
						final int verticalGravity = gravity & Gravity.VERTICAL_GRAVITY_MASK;
						stretched = verticalGravity == Gravity.FILL_VERTICAL;
					}

					// if stretched - view wants to be our size. So be it.
					// else - view wants to determine its own size. It can't be bigger than us.
					resultMode = stretched ? MeasureSpec.EXACTLY : MeasureSpec.AT_MOST;
					break;

				// Parent has imposed a maximum size on us
				case MeasureSpec.AT_MOST:
					resultSize = measureLength;
					resultMode = MeasureSpec.AT_MOST;
					break;

				case MeasureSpec.UNSPECIFIED:
					resultSize = 0;
					resultMode = MeasureSpec.UNSPECIFIED;
					break;
			}
		}

		return MeasureSpec.makeMeasureSpec(resultSize, resultMode);
	}
}