/*
 * This is the source code of Telegram for Android v. 1.3.x.
 * It is licensed under GNU GPL v. 2 or later.
 * You should have received a copy of the license in this archive (see LICENSE).
 *
 * Copyright Nikolai Kudashov, 2013.
 */

package org.telegram.ui.Cells;

import android.content.Context;
import android.graphics.Canvas;
import android.text.Spannable;
import android.text.style.ClickableSpan;
import android.view.MotionEvent;

import org.telegram.android.AndroidUtilities;
import org.telegram.messenger.FileLog;
import org.telegram.android.MessageObject;

public class ChatMessageCell extends ChatBaseCell {

    private int textX, textY;
    private int totalHeight = 0;
    private ClickableSpan pressedLink;

    private int lastVisibleBlockNum = 0;
    private int firstVisibleBlockNum = 0;
    private int totalVisibleBlocksCount = 0;

    public ChatMessageCell(Context context) {
        super(context, false);
        drawForwardedName = true;
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (currentMessageObject != null && currentMessageObject.textLayoutBlocks != null && !currentMessageObject.textLayoutBlocks.isEmpty() && currentMessageObject.messageText instanceof Spannable && !isPressed) {
            if (event.getAction() == MotionEvent.ACTION_DOWN || pressedLink != null && event.getAction() == MotionEvent.ACTION_UP) {
                int x = (int)event.getX();
                int y = (int)event.getY();
                if (x >= textX && y >= textY && x <= textX + currentMessageObject.textWidth && y <= textY + currentMessageObject.textHeight) {
                    y -= textY;
                    int blockNum = Math.max(0, y / currentMessageObject.blockHeight);
                    if (blockNum < currentMessageObject.textLayoutBlocks.size()) {
                        MessageObject.TextLayoutBlock block = currentMessageObject.textLayoutBlocks.get(blockNum);
                        x -= textX - (int)Math.ceil(block.textXOffset);
                        y -= block.textYOffset;
                        final int line = block.textLayout.getLineForVertical(y);
                        final int off = block.textLayout.getOffsetForHorizontal(line, x) + block.charactersOffset;

                        final float left = block.textLayout.getLineLeft(line);
                        if (left <= x && left + block.textLayout.getLineWidth(line) >= x) {
                            Spannable buffer = (Spannable)currentMessageObject.messageText;
                            ClickableSpan[] link = buffer.getSpans(off, off, ClickableSpan.class);

                            if (link.length != 0) {
                                if (event.getAction() == MotionEvent.ACTION_DOWN) {
                                    pressedLink = link[0];
                                    return true;
                                } else {
                                    if (link[0] == pressedLink) {
                                        try {
                                            pressedLink.onClick(this);
                                        } catch (Exception e) {
                                            FileLog.e("tmessages", e);
                                        }
                                        return true;
                                    }
                                }
                            } else {
                                pressedLink = null;
                            }
                        } else {
                            pressedLink = null;
                        }
                    } else {
                        pressedLink = null;
                    }
                } else {
                    pressedLink = null;
                }
            }
        } else {
            pressedLink = null;
        }
        return super.onTouchEvent(event);
    }

    public void setVisiblePart(int position, int height) {
        if (currentMessageObject == null || currentMessageObject.textLayoutBlocks == null) {
            return;
        }
        int newFirst = -1, newLast = -1, newCount = 0;

        for (int a = Math.max(0, (position - textY) / currentMessageObject.blockHeight); a < currentMessageObject.textLayoutBlocks.size(); a++) {
            MessageObject.TextLayoutBlock block = currentMessageObject.textLayoutBlocks.get(a);
            float y = textY + block.textYOffset;
            if (intersect(y, y + currentMessageObject.blockHeight, position, position + height)) {
                if (newFirst == -1) {
                    newFirst = a;
                }
                newLast = a;
                newCount++;
            } else if (y > position) {
                break;
            }
        }

        if (lastVisibleBlockNum != newLast || firstVisibleBlockNum != newFirst || totalVisibleBlocksCount != newCount) {
            lastVisibleBlockNum = newLast;
            firstVisibleBlockNum = newFirst;
            totalVisibleBlocksCount = newCount;
            invalidate();
        }
    }

    private boolean intersect(float left1, float right1, float left2, float right2) {
        if (left1 <= left2) {
            return right1 >= left2;
        }
        return left1 <= right2;
    }

    @Override
    public void setMessageObject(MessageObject messageObject) {
        if (currentMessageObject != messageObject || isUserDataChanged()) {
            if (currentMessageObject != messageObject) {
                firstVisibleBlockNum = 0;
                lastVisibleBlockNum = 0;
            }
            pressedLink = null;
            int maxWidth;
            if (isChat && !messageObject.isOut()) {
                maxWidth = AndroidUtilities.displaySize.x - AndroidUtilities.dp(122);
                drawName = true;
            } else {
                maxWidth = AndroidUtilities.displaySize.x - AndroidUtilities.dp(80);
                drawName = false;
            }

            backgroundWidth = maxWidth;

            super.setMessageObject(messageObject);

            backgroundWidth = messageObject.textWidth;
            totalHeight = messageObject.textHeight + AndroidUtilities.dpf(19.5f) + namesOffset;

            int maxChildWidth = Math.max(backgroundWidth, nameWidth);
            maxChildWidth = Math.max(maxChildWidth, forwardedNameWidth);

            int timeMore = timeWidth + AndroidUtilities.dp(6);
            if (messageObject.isOut()) {
                timeMore += AndroidUtilities.dpf(20.5f);
            }

            if (maxWidth - messageObject.lastLineWidth < timeMore) {
                totalHeight += AndroidUtilities.dp(14);
                backgroundWidth = Math.max(maxChildWidth, messageObject.lastLineWidth) + AndroidUtilities.dp(29);
            } else {
                int diff = maxChildWidth - messageObject.lastLineWidth;
                if (diff >= 0 && diff <= timeMore) {
                    backgroundWidth = maxChildWidth + timeMore - diff + AndroidUtilities.dp(29);
                } else {
                    backgroundWidth = Math.max(maxChildWidth, messageObject.lastLineWidth + timeMore) + AndroidUtilities.dp(29);
                }
            }
        }
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        setMeasuredDimension(MeasureSpec.getSize(widthMeasureSpec), totalHeight);
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);

        if (currentMessageObject.isOut()) {
            textX = layoutWidth - backgroundWidth + AndroidUtilities.dp(10);
            textY = AndroidUtilities.dp(10) + namesOffset;
        } else {
            textX = AndroidUtilities.dp(19) + (isChat ? AndroidUtilities.dp(52) : 0);
            textY = AndroidUtilities.dp(10) + namesOffset;
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        if (currentMessageObject == null || currentMessageObject.textLayoutBlocks == null || currentMessageObject.textLayoutBlocks.isEmpty() || firstVisibleBlockNum < 0) {
            return;
        }

        if (currentMessageObject.isOut()) {
            textX = layoutWidth - backgroundWidth + AndroidUtilities.dp(10);
            textY = AndroidUtilities.dp(10) + namesOffset;
        } else {
            textX = AndroidUtilities.dp(19) + (isChat ? AndroidUtilities.dp(52) : 0);
            textY = AndroidUtilities.dp(10) + namesOffset;
        }

        for (int a = firstVisibleBlockNum; a <= lastVisibleBlockNum; a++) {
            if (a >= currentMessageObject.textLayoutBlocks.size()) {
                break;
            }
            MessageObject.TextLayoutBlock block = currentMessageObject.textLayoutBlocks.get(a);
            canvas.save();
            canvas.translate(textX - (int)Math.ceil(block.textXOffset), textY + block.textYOffset);
            try {
                block.textLayout.draw(canvas);
            } catch (Exception e) {
                FileLog.e("tmessages", e);
            }
            canvas.restore();
        }
    }
}