/*
 * Copyright 2021 The Android Open Source Project
 *
 * 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
 *
 *      https://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.google.accompanist.sample.swiperefresh

import android.os.Bundle
import androidx.activity.ComponentActivity
import androidx.activity.compose.setContent
import androidx.compose.foundation.Image
import androidx.compose.foundation.background
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.aspectRatio
import androidx.compose.foundation.layout.fillMaxSize
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.wrapContentSize
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material.MaterialTheme
import androidx.compose.material.Scaffold
import androidx.compose.material.Surface
import androidx.compose.material.Text
import androidx.compose.material.TopAppBar
import androidx.compose.runtime.Composable
import androidx.compose.runtime.LaunchedEffect
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.res.stringResource
import androidx.compose.ui.unit.dp
import coil.annotation.ExperimentalCoilApi
import coil.compose.rememberImagePainter
import com.google.accompanist.pager.ExperimentalPagerApi
import com.google.accompanist.pager.VerticalPager
import com.google.accompanist.sample.AccompanistSampleTheme
import com.google.accompanist.sample.R
import com.google.accompanist.sample.randomSampleImageUrl
import com.google.accompanist.swiperefresh.SwipeRefresh
import com.google.accompanist.swiperefresh.rememberSwipeRefreshState
import kotlinx.coroutines.delay

class SwipeRefreshVerticalPagerSample : ComponentActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        setContent {
            AccompanistSampleTheme {
                Surface {
                    Sample()
                }
            }
        }
    }
}

@OptIn(ExperimentalPagerApi::class, ExperimentalCoilApi::class)
@Composable
private fun Sample() {
    Scaffold(
        topBar = {
            TopAppBar(
                title = { Text(stringResource(R.string.swiperefresh_title_verticalpager)) },
                backgroundColor = MaterialTheme.colors.surface,
            )
        },
        modifier = Modifier.fillMaxSize()
    ) { padding ->
        // Simulate a fake 2-second 'load'. Ideally this 'refreshing' value would
        // come from a ViewModel or similar
        var refreshing by remember { mutableStateOf(false) }
        LaunchedEffect(refreshing) {
            if (refreshing) {
                delay(2000)
                refreshing = false
            }
        }

        SwipeRefresh(
            state = rememberSwipeRefreshState(isRefreshing = refreshing),
            onRefresh = { refreshing = true },
        ) {
            VerticalPager(
                count = 10,
                itemSpacing = 8.dp,
                modifier = Modifier.fillMaxSize().padding(padding),
            ) { page ->
                Box {
                    // Our page content, displaying a random image
                    Image(
                        painter = rememberImagePainter(randomSampleImageUrl(width = 600)),
                        contentDescription = null,
                        modifier = Modifier
                            .fillMaxWidth()
                            .aspectRatio(1f)
                    )

                    // Displays the page index
                    Text(
                        text = page.toString(),
                        modifier = Modifier
                            .align(Alignment.BottomEnd)
                            .padding(16.dp)
                            .background(MaterialTheme.colors.surface, RoundedCornerShape(4.dp))
                            .padding(4.dp)
                            .wrapContentSize(Alignment.Center)
                    )
                }
            }
        }
    }
}
