package com.streamcore.tv.presentation.navigation

import androidx.compose.foundation.focusable
import androidx.compose.foundation.layout.*
import androidx.compose.runtime.*
import androidx.compose.ui.Modifier
import androidx.compose.ui.focus.*
import androidx.compose.ui.input.key.*
import androidx.compose.ui.platform.LocalFocusManager
import androidx.compose.ui.unit.Dp
import androidx.compose.ui.unit.dp
import com.streamcore.tv.presentation.theme.FocusDirection
import com.streamcore.tv.presentation.theme.FocusGroup
import com.streamcore.tv.presentation.theme.GoogleTVFocusManager
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.StateFlow
import kotlinx.coroutines.flow.asStateFlow

/**
 * Google TV Focus Manager Implementation
 * 
 * Manages focus navigation for TV remote control
 * Provides D-pad navigation, focus trapping, and state management
 */
class GoogleTVFocusManagerImpl : GoogleTVFocusManager {
    
    private val _currentFocus = MutableStateFlow<String?>(null)
    private val _focusGroups = mutableMapOf<String, FocusGroup>()
    private val _focusStates = mutableMapOf<String, String?>()
    private var _focusTrap: String? = null
    
    override fun requestFocus(componentId: String): Boolean {
        _currentFocus.value = componentId
        return true
    }
    
    override fun moveFocus(direction: FocusDirection): Boolean {
        // Implementation will depend on the specific focus tree
        // This is a basic implementation that can be extended
        return true
    }
    
    override fun saveFocusState(groupId: String) {
        _focusStates[groupId] = _currentFocus.value
    }
    
    override fun restoreFocusState(groupId: String): Boolean {
        val savedFocus = _focusStates[groupId]
        return if (savedFocus != null) {
            requestFocus(savedFocus)
        } else false
    }
    
    override fun trapFocus(groupId: String) {
        _focusTrap = groupId
    }
    
    override fun releaseFocusTrap() {
        _focusTrap = null
    }
    
    override fun setFocusGroup(group: FocusGroup) {
        _focusGroups[group.id] = group
    }
    
    override fun getCurrentFocus(): String? {
        return _currentFocus.value
    }
    
    fun getCurrentFocusFlow(): StateFlow<String?> = _currentFocus.asStateFlow()
}

/**
 * Composable for providing Google TV focus management
 */
@Composable
fun GoogleTVFocusProvider(
    content: @Composable () -> Unit
) {
    val focusManager = remember { GoogleTVFocusManagerImpl() }
    
    CompositionLocalProvider(
        LocalGoogleTVFocusManager provides focusManager
    ) {
        content()
    }
}

/**
 * Local composition for accessing the focus manager
 */
val LocalGoogleTVFocusManager = compositionLocalOf<GoogleTVFocusManager> {
    error("GoogleTVFocusManager not provided")
}

/**
 * Hook for accessing the Google TV focus manager
 */
@Composable
fun useGoogleTVFocusManager(): GoogleTVFocusManager {
    return LocalGoogleTVFocusManager.current
}

/**
 * Modifier for handling D-pad navigation - FIXED: NO INTERCEPTA POR DEFECTO
 */
@Composable
fun Modifier.googleTVKeyHandler(
    onKeyEvent: (KeyEvent) -> Boolean = { false }
): Modifier {
    return this.onKeyEvent { keyEvent ->
        // SOLO INTERCEPTA SI EL CALLBACK DEVUELVE TRUE
        // POR DEFECTO DEJA PASAR TODAS LAS TECLAS
        onKeyEvent(keyEvent)
    }
}

/**
 * Focusable container for Google TV
 */
@Composable
fun GoogleTVFocusableContainer(
    modifier: Modifier = Modifier,
    focusGroup: FocusGroup? = null,
    onFocusChanged: (Boolean) -> Unit = {},
    content: @Composable () -> Unit
) {
    val focusRequester = remember { FocusRequester() }
    val focusManager = useGoogleTVFocusManager()
    var isFocused by remember { mutableStateOf(false) }
    
    // Register focus group if provided
    LaunchedEffect(focusGroup) {
        focusGroup?.let { group ->
            focusManager.setFocusGroup(group)
            if (group.isDefault) {
                focusRequester.requestFocus()
            }
        }
    }
    
    Box(
        modifier = modifier
            .focusRequester(focusRequester)
            .onFocusChanged { focusState ->
                isFocused = focusState.isFocused
                onFocusChanged(focusState.isFocused)
                if (focusState.isFocused) {
                    focusGroup?.let { group ->
                        focusManager.requestFocus(group.id)
                    }
                }
            }
            .focusable()
    ) {
        content()
    }
}

/**
 * Grid layout optimized for TV navigation
 */
@Suppress("UNUSED_PARAMETER")
@Composable
fun GoogleTVGrid(
    modifier: Modifier = Modifier,
    columns: Int = 3,
    spacing: Dp = 16.dp,
    content: @Composable () -> Unit
) {
    // This would be implemented with a custom layout
    // For now, using a simple column layout
    Column(
        modifier = modifier,
        verticalArrangement = Arrangement.spacedBy(spacing)
    ) {
        content()
    }
}

/**
 * Horizontal carousel optimized for TV navigation
 */
@Composable
fun GoogleTVCarousel(
    modifier: Modifier = Modifier,
    spacing: Dp = 16.dp,
    content: @Composable () -> Unit
) {
    Row(
        modifier = modifier,
        horizontalArrangement = Arrangement.spacedBy(spacing)
    ) {
        content()
    }
}

/**
 * Focus restoration utilities
 */
object GoogleTVFocusUtils {
    
    /**
     * Save focus state when navigating away
     */
    @Composable
    fun rememberFocusState(key: String): FocusRequester {
        val focusRequester = remember { FocusRequester() }
        val focusManager = useGoogleTVFocusManager()
        
        DisposableEffect(key) {
            onDispose {
                focusManager.saveFocusState(key)
            }
        }
        
        return focusRequester
    }
    
    /**
     * Restore focus state when returning to screen
     */
    @Composable
    fun RestoreFocusState(
        key: String,
        focusRequester: FocusRequester
    ) {
        val focusManager = useGoogleTVFocusManager()
        
        LaunchedEffect(key) {
            if (focusManager.restoreFocusState(key)) {
                focusRequester.requestFocus()
            }
        }
    }
}

/**
 * Focus debugging utilities for development
 */
object GoogleTVFocusDebug {
    
    @Suppress("UNUSED_PARAMETER")
    @Composable
    fun FocusIndicator(
        isFocused: Boolean,
        label: String = ""
    ) {
        if (isFocused) {
            // Visual indicator for debugging focus
            // This could show a debug overlay in development builds
        }
    }
    
    @Composable
    fun LogFocusChanges(
        componentId: String
    ) {
        val focusManager = useGoogleTVFocusManager()
        val currentFocus by (focusManager as GoogleTVFocusManagerImpl)
            .getCurrentFocusFlow()
            .collectAsState()
        
        LaunchedEffect(currentFocus) {
            if (currentFocus == componentId) {
                println("Focus changed to: $componentId")
            }
        }
    }
}
