package com.peachpasswords.ui.vault

import android.content.ActivityNotFoundException
import android.content.Context
import android.content.Intent
import android.net.Uri
import android.widget.Toast
import androidx.compose.animation.core.LinearEasing
import androidx.compose.animation.core.animateFloatAsState
import androidx.compose.animation.core.tween
import androidx.compose.foundation.background
import androidx.compose.foundation.clickable
import androidx.compose.foundation.layout.Arrangement
import androidx.compose.foundation.layout.Box
import androidx.compose.foundation.layout.Column
import androidx.compose.foundation.layout.Row
import androidx.compose.foundation.layout.Spacer
import androidx.compose.foundation.layout.fillMaxWidth
import androidx.compose.foundation.layout.height
import androidx.compose.foundation.layout.padding
import androidx.compose.foundation.layout.size
import androidx.compose.foundation.layout.width
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.foundation.text.BasicTextField
import androidx.compose.material.icons.Icons
import androidx.compose.material.icons.automirrored.rounded.OpenInNew
import androidx.compose.material.icons.rounded.Check
import androidx.compose.material.icons.rounded.ContentCopy
import androidx.compose.material3.Icon
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
import androidx.compose.runtime.getValue
import androidx.compose.runtime.mutableStateOf
import androidx.compose.ui.Alignment
import androidx.compose.ui.Modifier
import androidx.compose.ui.draw.clip
import androidx.compose.ui.draw.drawBehind
import androidx.compose.ui.geometry.Offset
import androidx.compose.ui.geometry.Size
import androidx.compose.ui.graphics.Brush
import androidx.compose.ui.graphics.Color
import androidx.compose.ui.graphics.SolidColor
import androidx.compose.ui.platform.LocalContext
import androidx.compose.ui.text.TextStyle
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.em
import androidx.compose.ui.unit.sp
import androidx.compose.runtime.remember
import androidx.compose.runtime.setValue
import com.peachpasswords.ui.theme.LocalPeachAccent
import com.peachpasswords.ui.theme.LocalReduceMotion
import com.peachpasswords.ui.theme.peachColors
import com.peachpasswords.ui.theme.PeachType
import java.net.URI

/**
 * E3 — additional-URL rows for EntryDetailScreen. Self-contained: it carries its
 * own field shell, copy button, and open-in-browser control so it can be inserted
 * into the detail field stack without touching the screen's private `FieldShell`
 * / `CopyButton`. Each row shows "URL N", the value, copy, and open-in-browser.
 *
 * `copiedKeyFor(index)` is the per-row clipboard latch key the caller passes to
 * `vm.copy(key, value)`; `copiedField` is the screen's current latch.
 */
@Composable
fun AdditionalUrlRows(
    urls: List<String>,
    copiedField: String?,
    onCopy: (key: String, value: String) -> Unit,
    onSave: (index: Int, value: String) -> Unit = { _, _ -> },
    onAdd: (value: String) -> Unit = {},
    showAdd: Boolean = false,
) {
    val context = LocalContext.current
    urls.forEachIndexed { index, url ->
        if (url.isNotBlank()) {
            val key = additionalUrlCopyKey(index)
            var editing by remember(url) { mutableStateOf(false) }
            var draft by remember(url) { mutableStateOf(url) }
            AdditionalUrlFieldShell(label = "URL ${index + 2}") {
                if (editing) {
                    Column(Modifier.weight(1f)) {
                        AdditionalUrlInlineField(
                            draft = draft,
                            onDraftChange = { draft = it },
                            modifier = Modifier.fillMaxWidth(),
                        )
                        Spacer(Modifier.height(8.dp))
                        AdditionalUrlSaveCancelRow(
                            onSave = { onSave(index, draft); editing = false },
                            onCancel = { draft = url; editing = false },
                        )
                    }
                } else {
                    Text(
                        url,
                        color = peachColors.T0,
                        style = PeachType.bodyMono,
                        modifier = Modifier.weight(1f).clickable { draft = url; editing = true },
                    )
                    OpenInBrowserButton(onClick = { openUrlInBrowser(context, url) })
                    Spacer(Modifier.width(4.dp))
                    AdditionalUrlCopyButton(copied = copiedField == key, onCopy = { onCopy(key, url) })
                }
            }
        }
    }
    if (showAdd) AddAdditionalUrlRow(onAdd = onAdd)
}

@Composable
private fun AdditionalUrlInlineField(
    draft: String,
    onDraftChange: (String) -> Unit,
    modifier: Modifier = Modifier,
) {
    val accent = LocalPeachAccent.current
    BasicTextField(
        value = draft,
        onValueChange = onDraftChange,
        singleLine = true,
        textStyle = PeachType.bodyMono.copy(color = peachColors.T0),
        cursorBrush = SolidColor(accent),
        modifier = modifier
            .padding(bottom = 4.dp)
            .drawBehind {
                drawLine(
                    color = accent,
                    start = Offset(0f, size.height),
                    end = Offset(size.width, size.height),
                    strokeWidth = 1.dp.toPx(),
                )
            },
    )
}

@Composable
private fun AdditionalUrlSaveCancelRow(onSave: () -> Unit, onCancel: () -> Unit) {
    val accent = LocalPeachAccent.current
    Row(horizontalArrangement = Arrangement.spacedBy(16.dp), verticalAlignment = Alignment.CenterVertically) {
        Text(
            "✓ save", color = accent, style = PeachType.labelMono,
            modifier = Modifier.clip(RoundedCornerShape(6.dp)).clickable(onClick = onSave).padding(vertical = 4.dp),
        )
        Text(
            "✗", color = peachColors.T2, style = PeachType.labelMono,
            modifier = Modifier.clip(RoundedCornerShape(6.dp)).clickable(onClick = onCancel).padding(horizontal = 6.dp, vertical = 4.dp),
        )
    }
}

@Composable
private fun AddAdditionalUrlRow(onAdd: (String) -> Unit) {
    val accent = LocalPeachAccent.current
    var editing by remember { mutableStateOf(false) }
    var draft by remember { mutableStateOf("") }
    if (!editing) {
        Text(
            "+ add another url",
            color = accent,
            style = PeachType.labelMono,
            modifier = Modifier
                .clip(RoundedCornerShape(6.dp))
                .clickable { editing = true }
                .padding(vertical = 6.dp),
        )
        return
    }
    AdditionalUrlFieldShell(label = "new url") {
        Column(Modifier.weight(1f)) {
            AdditionalUrlInlineField(
                draft = draft,
                onDraftChange = { draft = it },
                modifier = Modifier.fillMaxWidth(),
            )
            Spacer(Modifier.height(8.dp))
            AdditionalUrlSaveCancelRow(
                onSave = {
                    onAdd(draft)
                    draft = ""
                    editing = false
                },
                onCancel = {
                    draft = ""
                    editing = false
                },
            )
        }
    }
}

/** Per-row clipboard latch key; keeps each URL's copy feedback independent. */
fun additionalUrlCopyKey(index: Int): String = "additionalUrl:$index"

/**
 * Launches ACTION_VIEW only for a canonical HTTPS URL. Stored/imported vault
 * values are untrusted; non-web schemes never cross into another app.
 */
fun openUrlInBrowser(context: Context, raw: String) {
    val normalized = normalizeExternalHttpsUrl(raw)
    if (normalized == null) {
        Toast.makeText(context, "Only valid HTTPS links can be opened", Toast.LENGTH_SHORT).show()
        return
    }
    try {
        context.startActivity(
            Intent(Intent.ACTION_VIEW, Uri.parse(normalized)).apply {
                addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
            },
        )
    } catch (_: ActivityNotFoundException) {
        Toast.makeText(context, "No app can open this link", Toast.LENGTH_SHORT).show()
    }
}

/** Returns a canonical HTTPS URL or null when external dispatch is unsafe. */
internal fun normalizeExternalHttpsUrl(raw: String): String? {
    val value = raw.trim()
    if (value.isEmpty() || value.any { it <= '\u001F' || it == '\u007F' || it == '\\' }) return null

    val hasScheme = SCHEME_PREFIX.containsMatchIn(value)
    val candidate = if (hasScheme) value else "https://$value"
    val parsed = runCatching { URI(candidate) }.getOrNull() ?: return null
    if (!parsed.scheme.equals("https", ignoreCase = true) || parsed.isOpaque) return null
    if (parsed.rawAuthority.isNullOrBlank() || parsed.userInfo != null) return null
    val host = parsed.host?.takeIf { it.isNotBlank() } ?: return null
    if (parsed.port !in -1..65535) return null

    return runCatching {
        URI(
            "https",
            null,
            host.lowercase(),
            parsed.port,
            parsed.path.orEmpty(),
            parsed.query,
            parsed.fragment,
        ).toASCIIString()
    }.getOrNull()
}

private val SCHEME_PREFIX = Regex("^[A-Za-z][A-Za-z0-9+.-]*:")

/** Mirrors EntryDetailScreen's private FieldShell: mono label over a value/action row with a t3 hairline. */
@Composable
private fun AdditionalUrlFieldShell(
    label: String,
    content: @Composable androidx.compose.foundation.layout.RowScope.() -> Unit,
) {
    val hairline = peachColors.T3
    Column(
        Modifier.fillMaxWidth().padding(vertical = 10.dp).drawBehind {
            drawRect(
                color = hairline,
                topLeft = Offset(0f, size.height - 1.dp.toPx()),
                size = Size(size.width, 1.dp.toPx()),
            )
        },
    ) {
        Text(label.uppercase(), color = peachColors.T2, style = PeachType.labelMono.copy(letterSpacing = 0.08.em))
        Spacer(Modifier.height(6.dp))
        Row(verticalAlignment = Alignment.CenterVertically, content = content)
    }
}

@Composable
private fun OpenInBrowserButton(onClick: () -> Unit) {
    Box(
        Modifier
            .size(36.dp)
            .clip(RoundedCornerShape(6.dp))
            .background(peachColors.S2)
            .clickable(onClick = onClick),
        contentAlignment = Alignment.Center,
    ) {
        Icon(
            Icons.AutoMirrored.Rounded.OpenInNew,
            contentDescription = "open in browser",
            tint = peachColors.T2,
            modifier = Modifier.size(15.dp),
        )
    }
}

/** Mirrors EntryDetailScreen's private CopyButton (sheen sweep + drain bar, spec §4.4). */
@Composable
private fun AdditionalUrlCopyButton(copied: Boolean, onCopy: () -> Unit) {
    val accent = LocalPeachAccent.current
    val reduceMotion = LocalReduceMotion.current
    val animate = copied && !reduceMotion
    val drain by animateFloatAsState(
        targetValue = if (copied) 1f else 0f,
        animationSpec = if (animate) tween(1400, easing = LinearEasing) else tween(0),
        label = "url-copy-drain",
    )
    val sheen by animateFloatAsState(
        targetValue = if (copied) 1f else 0f,
        animationSpec = if (animate) tween(600, easing = LinearEasing) else tween(0),
        label = "url-copy-sheen",
    )
    Box(
        Modifier
            .size(36.dp)
            .clip(RoundedCornerShape(6.dp))
            .background(peachColors.S2)
            .clickable(onClick = onCopy)
            .drawBehind {
                if (animate && sheen < 1f) {
                    val sweepX = (sheen * 2f - 0.5f) * size.width
                    val band = size.width * 0.5f
                    drawRect(
                        brush = Brush.linearGradient(
                            colors = listOf(Color.Transparent, accent.copy(alpha = 0.35f), Color.Transparent),
                            start = Offset(sweepX - band, 0f),
                            end = Offset(sweepX + band, size.height),
                        ),
                    )
                }
                if (drain > 0f) {
                    val h = 2.dp.toPx()
                    drawRect(
                        color = accent,
                        topLeft = Offset(0f, size.height - h),
                        size = Size(size.width * drain, h),
                    )
                }
            },
        contentAlignment = Alignment.Center,
    ) {
        Icon(
            if (copied) Icons.Rounded.Check else Icons.Rounded.ContentCopy,
            contentDescription = "copy",
            tint = if (copied) accent else peachColors.T1,
            modifier = Modifier.size(15.dp),
        )
    }
}