/*
 * mygram-droid: Android TV client for Foldergram.
 * Copyright (C) 2026 Danilo M. <danix@danix.xyz>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * for more details.
 */

package mygram.droid;

import android.app.Activity;
import android.content.Context;
import android.graphics.Color;
import android.graphics.RenderEffect;
import android.graphics.Shader;
import android.graphics.drawable.GradientDrawable;
import android.text.InputType;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;

import androidx.recyclerview.widget.GridLayoutManager;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.Glide;

import java.util.ArrayList;
import java.util.List;

/** View helpers. The UI is built in code, there are no layout files. */
final class Ui {
	static final int RED = 0xFFFF3B5C;
	/** Pink end of the app icon gradient. */
	static final int ACCENT = 0xFFEC4899;
	/** Post tiles: portrait, most media is 9:16. */
	static final int POST_W = 128, POST_H = 228;

	private Ui() {
	}

	static int dp(Context c, float v) {
		return Math.round(v * c.getResources().getDisplayMetrics().density);
	}

	static TextView text(Context c, String s, int sp) {
		TextView t = new TextView(c);
		t.setText(s);
		t.setTextSize(sp);
		t.setTextColor(Color.WHITE);
		return t;
	}

	static LinearLayout column(Context c) {
		LinearLayout box = new LinearLayout(c);
		box.setOrientation(LinearLayout.VERTICAL);
		box.setGravity(Gravity.CENTER);
		int p = dp(c, 32);
		box.setPadding(p, p, p, p);
		return box;
	}

	static LinearLayout row(Context c) {
		LinearLayout row = new LinearLayout(c);
		row.setGravity(Gravity.CENTER);
		return row;
	}

	static EditText field(Context c, String hint, int inputType) {
		EditText e = new EditText(c);
		e.setHint(hint);
		// setSingleLine() resets the input type's transformation, unmasking
		// passwords; it must come first.
		e.setSingleLine(true);
		e.setInputType(inputType);
		e.setTextColor(Color.WHITE);
		e.setHintTextColor(Color.GRAY);
		e.setMinWidth(dp(c, 400));
		return e;
	}

	static int password() {
		return InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD;
	}

	/** Focus ring and a small zoom: the only focus feedback on a TV. */
	static void focusable(View v) {
		v.setFocusable(true);
		v.setForeground(v.getContext().getDrawable(R.drawable.focus_ring));
		v.setOnFocusChangeListener((x, has) -> zoom(x, has));
	}

	private static void zoom(View v, boolean in) {
		v.animate().scaleX(in ? 1.08f : 1f).scaleY(in ? 1.08f : 1f).setDuration(120).start();
	}

	/**
	 * Icon-only button. Focus scales the icon and turns it accent pink, and
	 * shows the label under it. Child 1 is the current-view mark.
	 */
	static LinearLayout iconButton(Context c, int icon, String label, View.OnClickListener click) {
		LinearLayout box = new LinearLayout(c);
		box.setOrientation(LinearLayout.VERTICAL);
		box.setGravity(Gravity.CENTER_HORIZONTAL);
		int p = dp(c, 10);
		box.setPadding(p, p, p, p / 2);
		box.setClipToPadding(false); // the focus zoom draws into the padding; the full-bleed logo was cut
		ImageView image = new ImageView(c);
		image.setImageResource(icon);
		image.setContentDescription(label);
		image.setAlpha(0.7f);
		int s = dp(c, 36);
		box.addView(image, new LinearLayout.LayoutParams(s, s));
		GradientDrawable bar = new GradientDrawable();
		bar.setColor(ACCENT);
		bar.setCornerRadius(dp(c, 2));
		View mark = new View(c);
		mark.setBackground(bar);
		mark.setVisibility(View.INVISIBLE);
		LinearLayout.LayoutParams mp = new LinearLayout.LayoutParams(dp(c, 20), dp(c, 3));
		mp.topMargin = dp(c, 8); // clears the 1.25 focus zoom
		box.addView(mark, mp);
		TextView t = text(c, label, 12);
		t.setSingleLine(true);
		t.setVisibility(View.INVISIBLE);
		// WRAP_CONTENT: the vertical default, MATCH_PARENT, does not widen the box, so long labels were clipped
		box.addView(t, new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
				ViewGroup.LayoutParams.WRAP_CONTENT));
		boolean tint = icon != R.drawable.ic_launcher; // the logo keeps its colours
		box.setFocusable(true);
		box.setOnFocusChangeListener((v, has) -> {
			t.setVisibility(has ? View.VISIBLE : View.INVISIBLE);
			image.setAlpha(has ? 1f : 0.7f);
			if (tint && has)
				image.setColorFilter(ACCENT);
			else
				image.clearColorFilter();
			image.animate().scaleX(has ? 1.25f : 1f).scaleY(has ? 1.25f : 1f).setDuration(120).start();
		});
		box.setOnClickListener(click);
		return box;
	}

	/** Shows or hides the mark under an iconButton that stands for the current view. */
	static void markCurrent(LinearLayout button, boolean current) {
		button.getChildAt(1).setVisibility(current ? View.VISIBLE : View.INVISIBLE);
	}

	/** Back arrow and title, for screens outside the main view. */
	static LinearLayout header(Activity a, String title) {
		return header(a, title, null);
	}

	/** Back arrow, the folder picture when there is one, and title. */
	static LinearLayout header(Activity a, String title, String avatarUrl) {
		LinearLayout header = new LinearLayout(a);
		header.setGravity(Gravity.CENTER_VERTICAL);
		int p = dp(a, 16);
		header.setPadding(p * 2, p, p * 2, 0);
		header.addView(iconButton(a, R.drawable.ic_arrow_back, "Back", v -> a.finish()));
		ImageView avatar = avatar(a, 40);
		((LinearLayout.LayoutParams) avatar.getLayoutParams()).leftMargin = p;
		header.addView(avatar);
		setAvatar(avatar, avatarUrl);
		TextView t = text(a, title, 24);
		t.setPadding(p, 0, 0, 0);
		header.addView(t);
		return header;
	}

	/** A round folder picture of size dp, for a horizontal LinearLayout. */
	static ImageView avatar(Context c, int size) {
		ImageView v = new ImageView(c);
		v.setLayoutParams(new LinearLayout.LayoutParams(dp(c, size), dp(c, size)));
		return v;
	}

	/** Loads url round, or hides the view when the folder has no picture. */
	static void setAvatar(ImageView v, String url) {
		v.setVisibility(url == null ? View.GONE : View.VISIBLE);
		if (url == null)
			Glide.with(v).clear(v);
		else
			Glide.with(v).load(url).circleCrop().into(v);
	}

	static void blur(ImageView v, float radius) {
		v.setRenderEffect(RenderEffect.createBlurEffect(radius, radius, Shader.TileMode.CLAMP));
	}

	static RecyclerView list(Context c, int orientation) {
		RecyclerView rv = new RecyclerView(c);
		rv.setLayoutManager(new LinearLayoutManager(c, orientation, false));
		int p = dp(c, 24);
		rv.setPadding(p, 0, p, 0);
		rv.setClipToPadding(false);
		return rv;
	}

	static RecyclerView grid(Context c, List<TileAdapter.Tile> tiles, int w, int h, int span) {
		RecyclerView rv = new RecyclerView(c);
		rv.setLayoutManager(new GridLayoutManager(c, span));
		rv.setAdapter(new TileAdapter(tiles, w, h));
		int p = dp(c, 24);
		rv.setPadding(p, p, p, p);
		rv.setClipToPadding(false);
		return rv;
	}

	/** Tiles that open the viewer on posts, starting at the chosen one. */
	static List<TileAdapter.Tile> postTiles(Context c, List<Post> posts) {
		List<TileAdapter.Tile> tiles = new ArrayList<>();
		for (int i = 0; i < posts.size(); i++) {
			int start = i;
			tiles.add(TileAdapter.post(posts.get(i), () -> Playlist.open(c, posts, start, null)));
		}
		return tiles;
	}
}