amethyst/app/src/main/java/com/vitorpamplona/amethyst/ui/components/RichTextViewer.kt

package com.vitorpamplona.amethyst.ui.components

import android.util.Patterns
import androidx.compose.animation.animateContentSize
import androidx.compose.foundation.background
import androidx.compose.foundation.border
import androidx.compose.foundation.layout.*
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material.*
import androidx.compose.runtime.*
import androidx.compose.runtime.livedata.observeAsState
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.compositeOver
import androidx.compose.ui.text.style.TextDirection
import androidx.compose.ui.unit.dp
import androidx.navigation.NavController
import com.google.accompanist.flowlayout.FlowRow
import com.vitorpamplona.amethyst.lnurl.LnInvoiceUtil
import com.vitorpamplona.amethyst.model.LocalCache
import com.vitorpamplona.amethyst.model.toByteArray
import com.vitorpamplona.amethyst.model.toNote
import com.vitorpamplona.amethyst.service.Nip19
import com.vitorpamplona.amethyst.ui.note.NoteCompose
import com.vitorpamplona.amethyst.ui.note.toShortenHex
import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
import nostr.postr.toNpub
import java.net.MalformedURLException
import java.net.URISyntaxException
import java.net.URL
import java.util.regex.Pattern

val imageExtension = Pattern.compile("(.*/)*.+\\.(png|jpg|gif|bmp|jpeg|webp|svg)$")
val videoExtension = Pattern.compile("(.*/)*.+\\.(mp4|avi|wmv|mpg|amv|webm)$")
val noProtocolUrlValidator = Pattern.compile("^[-a-zA-Z0-9@:%._\\+~#=]{1,256}\\.[a-zA-Z0-9()]{1,6}\\b(?:[-a-zA-Z0-9()@:%_\\+.~#?&//=]*)$")
val tagIndex = Pattern.compile(".*\\#\\[([0-9]+)\\].*")

val mentionsPattern: Pattern = Pattern.compile("@([A-Za-z0-9_-]+)")
val hashTagsPattern: Pattern = Pattern.compile("#([A-Za-z0-9_-]+)")
val urlPattern: Pattern = Patterns.WEB_URL

fun isValidURL(url: String?): Boolean {
  return try {
    URL(url).toURI()
    true
  } catch (e: MalformedURLException) {
    false
  } catch (e: URISyntaxException) {
    false
  }
}

@Composable
fun RichTextViewer(
  content: String,
  canPreview: Boolean,
  modifier: Modifier = Modifier,
  tags: List<List<String>>?,
  backgroundColor: Color,
  accountViewModel: AccountViewModel,
  navController: NavController,
) {
  Column(modifier = modifier.animateContentSize()) {
    // FlowRow doesn't work well with paragraphs. So we need to split them
    content.split('\n').forEach { paragraph ->

      FlowRow() {
        paragraph.split(' ').forEach { word: String ->

          if (canPreview) {
            // Explicit URL
            val lnInvoice = LnInvoiceUtil.findInvoice(word)
            if (lnInvoice != null) {
              InvoicePreview(lnInvoice)
            } else if (isValidURL(word)) {
              val removedParamsFromUrl = word.split("?")[0].toLowerCase()
              if (imageExtension.matcher(removedParamsFromUrl).matches()) {
                ZoomableImageView(word)
              } else if (videoExtension.matcher(removedParamsFromUrl).matches()) {
                VideoView(word)
              } else {
                UrlPreview(word, word)
              }
            } else if (Patterns.EMAIL_ADDRESS.matcher(word).matches()) {
              ClickableEmail(word)
            } else if (Patterns.PHONE.matcher(word).matches() && word.length > 6) {
              ClickablePhone(word)
            } else if (noProtocolUrlValidator.matcher(word).matches()) {
              UrlPreview("https://$word", word)
            } else if (tagIndex.matcher(word).matches() && tags != null) {
              TagLink(word, tags, backgroundColor, accountViewModel, navController)
            } else if (isBechLink(word)) {
              BechLink(word, navController)
            } else {
              Text(
                text = "$word ",
                style = LocalTextStyle.current.copy(textDirection = TextDirection.Content),
              )
            }
          } else {
            if (isValidURL(word)) {
              ClickableUrl("$word ", word)
            } else if (Patterns.EMAIL_ADDRESS.matcher(word).matches()) {
              ClickableEmail(word)
            } else if (Patterns.PHONE.matcher(word).matches() && word.length > 6) {
              ClickablePhone(word)
            } else if (noProtocolUrlValidator.matcher(word).matches()) {
              ClickableUrl(word, "https://$word")
            } else if (tagIndex.matcher(word).matches() && tags != null) {
              TagLink(word, tags, backgroundColor, accountViewModel, navController)
            } else if (isBechLink(word)) {
              BechLink(word, navController)
            } else {
              Text(
                text = "$word ",
                style = LocalTextStyle.current.copy(textDirection = TextDirection.Content),
              )
            }
          }
        }
      }
    }
  }
}


fun isBechLink(word: String): Boolean {
  return word.startsWith("nostr:", true)
    || word.startsWith("npub1", true)
    || word.startsWith("note1", true)
    || word.startsWith("nprofile1", true)
    || word.startsWith("nevent1", true)
    || word.startsWith("@npub1", true)
    || word.startsWith("@note1", true)
    || word.startsWith("@nprofile1", true)
    || word.startsWith("@nevent1", true)
}

@Composable
fun BechLink(word: String, navController: NavController) {
  val uri = if (word.startsWith("nostr", true)) {
    word
  } else if (word.startsWith("@")) {
    word.replaceFirst("@", "nostr:")
  } else {
    "nostr:${word}"
  }

  val nip19Route = try {
    Nip19().uriToRoute(uri)
  } catch (e: Exception) {
    null
  }

  if (nip19Route == null) {
    Text(text = "$word ")
  } else {
    ClickableRoute(nip19Route, navController)
  }
}


@Composable
fun TagLink(word: String, tags: List<List<String>>, backgroundColor: Color, accountViewModel: AccountViewModel, navController: NavController) {
  val matcher = tagIndex.matcher(word)

  val index = try {
    matcher.find()
    matcher.group(1).toInt()
  } catch (e: Exception) {
    println("Couldn't link tag ${word}")
    null
  }

  if (index == null) {
    return Text(text = "$word ")
  }

  if (index >= 0 && index < tags.size) {
    if (tags[index][0] == "p") {
      val baseUser = LocalCache.checkGetOrCreateUser(tags[index][1])
      if (baseUser != null) {
        val userState = baseUser.live().metadata.observeAsState()
        val user = userState.value?.user
        if (user != null) {
          ClickableUserTag(user, navController)
        } else {
          Text(text = "$word ")
        }
      } else {
        // if here the tag is not a valid Nostr Hex
        Text(text = "$word ")
      }
    } else if (tags[index][0] == "e") {
      val note = LocalCache.checkGetOrCreateNote(tags[index][1])
      if (note != null) {
        //ClickableNoteTag(note, navController)
        NoteCompose(
          baseNote = note,
          accountViewModel = accountViewModel,
          modifier = Modifier
            .padding(0.dp)
            .fillMaxWidth()
            .clip(shape = RoundedCornerShape(15.dp))
            .border(
              1.dp,
              MaterialTheme.colors.onSurface.copy(alpha = 0.12f),
              RoundedCornerShape(15.dp)
            ),
          parentBackgroundColor = MaterialTheme.colors.onSurface.copy(alpha = 0.05f).compositeOver(backgroundColor),
          isQuotedNote = true,
          navController = navController)
      } else {
        // if here the tag is not a valid Nostr Hex
        Text(text = "$word ")
      }
    } else
      Text(text = "$word ")
  }
}