package com.peachpasswords.ui.vault

import androidx.compose.foundation.background
import androidx.compose.foundation.border
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.width
import androidx.compose.foundation.shape.RoundedCornerShape
import androidx.compose.material3.Text
import androidx.compose.runtime.Composable
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.draw.clip
import androidx.compose.ui.text.font.FontStyle
import androidx.compose.ui.unit.dp
import androidx.compose.ui.unit.sp
import com.peachpasswords.ui.theme.LocalPeachAccent
import com.peachpasswords.ui.theme.PeachSpacing
import com.peachpasswords.ui.theme.peachColors
import com.peachpasswords.ui.theme.PeachType
import com.peachpasswords.vault.PasswordHistoryItem

/**
 * Shared past-password history UI, extracted from EntryEditScreen so both the
 * editor and EntryDetailScreen render the same rows. Behavior is unchanged from
 * the original private copy.
 *
 * - [PasswordHistorySection] is the original combined toggle + content block used
 *   by EntryEditScreen (toggle always present so the affordance is discoverable;
 *   empty state explains how it fills).
 * - [PasswordHistoryToggle] + [PasswordHistoryList] split the same pieces apart so
 *   EntryDetailScreen can drive expand/collapse with AnimatedVisibility itself.
 *
 * Rows are masked until revealed; "use" hands the value to [onRestore].
 */
@Composable
internal fun PasswordHistorySection(
    history: List<PasswordHistoryItem>,
    expanded: Boolean,
    onToggle: () -> Unit,
    onRestore: (String) -> Unit,
    onCopy: (String) -> Unit,
) {
    PasswordHistoryToggle(
        count = history.size,
        expanded = expanded,
        onToggle = onToggle,
        modifier = Modifier.fillMaxWidth().padding(horizontal = PeachSpacing.lg, vertical = PeachSpacing.sm),
    )
    if (expanded) {
        Box(Modifier.fillMaxWidth().height(1.dp).background(peachColors.T3))
        Column(Modifier.fillMaxWidth().padding(horizontal = PeachSpacing.lg, vertical = PeachSpacing.md)) {
            PasswordHistoryList(history = history, onRestore = onRestore, onCopy = onCopy)
        }
    }
}

/**
 * The "↺ history (N)" affordance — Cormorant italic, accent-tinted. Shows a bare
 * "↺ history" when empty and "↺ hide history" when [expanded].
 */
@Composable
internal fun PasswordHistoryToggle(
    count: Int,
    expanded: Boolean,
    onToggle: () -> Unit,
    modifier: Modifier = Modifier,
) {
    val accent = LocalPeachAccent.current
    val label = if (count == 0) "↺ history" else "↺ history ($count)"
    Text(
        if (expanded) "↺ hide history" else label,
        color = accent.copy(alpha = 0.7f),
        fontFamily = PeachType.Display,
        fontStyle = FontStyle.Italic,
        fontSize = 15.sp,
        modifier = modifier.clip(RoundedCornerShape(6.dp)).clickable(onClick = onToggle).padding(vertical = 4.dp),
    )
}

/**
 * The expanded body: either the empty-state explainer or the list of past
 * passwords. Caller owns the expand/collapse (and any AnimatedVisibility wrap).
 */
@Composable
internal fun PasswordHistoryList(
    history: List<PasswordHistoryItem>,
    onRestore: (String) -> Unit,
    onCopy: (String) -> Unit,
) {
    val accent = LocalPeachAccent.current
    if (history.isEmpty()) {
        Text(
            "No earlier passwords yet. When you change this password, the old one is saved here so you can copy or restore it.",
            color = peachColors.T2,
            fontFamily = PeachType.Mono,
            fontSize = 10.sp,
            modifier = Modifier.fillMaxWidth().padding(vertical = 2.dp),
        )
    } else {
        Column(verticalArrangement = Arrangement.spacedBy(6.dp)) {
            history.forEach { item -> HistoryRow(item, onRestore, onCopy) }
        }
    }
}

@Composable
private fun HistoryRow(
    item: PasswordHistoryItem,
    onRestore: (String) -> Unit,
    onCopy: (String) -> Unit,
) {
    val accent = LocalPeachAccent.current
    var revealed by remember { mutableStateOf(false) }
    Row(
        Modifier.fillMaxWidth().clip(RoundedCornerShape(8.dp))
            .border(1.dp, accent.copy(alpha = 0.12f), RoundedCornerShape(8.dp))
            .background(accent.copy(alpha = 0.06f)).padding(horizontal = 10.dp, vertical = 8.dp),
        verticalAlignment = Alignment.CenterVertically,
        horizontalArrangement = Arrangement.SpaceBetween,
    ) {
        Column(Modifier.weight(1f)) {
            Text(
                if (revealed) item.password else "••••••••••••",
                color = peachColors.T0, fontFamily = PeachType.Mono, fontSize = 12.sp, maxLines = 1,
            )
            Text(
                timeSince(item.changedAt),
                color = accent.copy(alpha = 0.55f), fontFamily = PeachType.Mono, fontSize = 8.sp,
            )
        }
        Spacer(Modifier.width(6.dp))
        HistoryAction(if (revealed) "hide" else "show") { revealed = !revealed }
        HistoryAction("copy") { onCopy(item.password) }
        HistoryAction("use") { onRestore(item.password) }
    }
}

@Composable
private fun HistoryAction(label: String, onClick: () -> Unit) {
    Text(
        label, color = LocalPeachAccent.current.copy(alpha = 0.7f),
        fontFamily = PeachType.Mono, fontSize = 9.sp,
        modifier = Modifier.clip(RoundedCornerShape(5.dp)).clickable(onClick = onClick).padding(horizontal = 5.dp, vertical = 3.dp),
    )
}

/** Coarse "time since" label for the history list. Mirrors the browser helper. */
private fun timeSince(whenMs: Long): String {
    val secs = ((System.currentTimeMillis() - whenMs) / 1000).coerceAtLeast(0)
    if (secs < 60) return "just now"
    val mins = secs / 60
    if (mins < 60) return "${mins}m ago"
    val hours = mins / 60
    if (hours < 24) return "${hours}h ago"
    val days = hours / 24
    if (days < 30) return "${days}d ago"
    val months = days / 30
    if (months < 12) return "${months}mo ago"
    return "${months / 12}y ago"
}