package com.example.shiftalarm

import android.content.Context
import android.content.res.ColorStateList
import android.graphics.Color
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.ImageView
import android.widget.TextView
import androidx.core.content.ContextCompat
import androidx.recyclerview.widget.RecyclerView
import java.time.LocalDate

data class DayShift(
    val date: LocalDate?, 
    val shift: String?, 
    val hasMemo: Boolean = false,
    val memoContent: String? = null
)

class CalendarAdapter(
    var days: List<DayShift>,
    private val listener: OnDayClickListener,
    var showHolidays: Boolean = true
) : RecyclerView.Adapter<CalendarAdapter.ViewHolder>() {

    interface OnDayClickListener {
        fun onDayClick(date: LocalDate, currentShift: String)
    }

    class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
        val root: View = view.findViewById(R.id.dayRoot)
        val dayNumber: TextView = view.findViewById(R.id.dayNumber)
        val shiftChar: TextView = view.findViewById(R.id.shiftChar)
        val holidayNameSmall: TextView = view.findViewById(R.id.holidayNameSmall)
        val memoIndicator: ImageView = view.findViewById(R.id.memoIndicator)
        val tvTide: TextView = view.findViewById(R.id.tvTide)
        val memoContent: TextView = view.findViewById(R.id.memoContent)
    }

    override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
        val view = LayoutInflater.from(parent.context).inflate(R.layout.item_day, parent, false)
        return ViewHolder(view)
    }

    private fun dpToPx(context: Context, dp: Float): Int {
        return (dp * context.resources.displayMetrics.density).toInt()
    }

    override fun onBindViewHolder(holder: ViewHolder, position: Int) {
        val item = days[position]
        val context = holder.itemView.context
        
        if (item.date == null) {
            holder.itemView.visibility = View.INVISIBLE
            return
        }
        
        holder.itemView.visibility = View.VISIBLE
        
        // Day Number
        holder.dayNumber.text = item.date.dayOfMonth.toString()
        
        // Holiday / Weekend logic
        val isSunday = item.date.dayOfWeek == java.time.DayOfWeek.SUNDAY
        val isSaturday = item.date.dayOfWeek == java.time.DayOfWeek.SATURDAY
        val fullHolidayName = HolidayManager.getHolidayName(item.date)
        val isToday = item.date == LocalDate.now()

        // Day Number Color
        if (fullHolidayName != null || isSunday) {
            holder.dayNumber.setTextColor(Color.parseColor("#FF5252"))
        } else if (isSaturday) {
            holder.dayNumber.setTextColor(Color.parseColor("#448AFF"))
        } else {
            holder.dayNumber.setTextColor(ContextCompat.getColor(context, R.color.text_primary))
        }

        // Tide Display
        val prefs = context.getSharedPreferences("ShiftAlarmPrefs", Context.MODE_PRIVATE)
        val showTide = prefs.getBoolean("show_tide", false)
        val tideLocation = prefs.getString("selected_tide_location", "군산") ?: "군산"
        
        if (showTide) {
            val tide = HolidayManager.getTide(item.date, tideLocation)
            if (tide.isNotEmpty()) {
                holder.tvTide.visibility = View.VISIBLE
                holder.tvTide.text = tide
            } else {
                holder.tvTide.visibility = View.GONE
            }
        } else {
             holder.tvTide.visibility = View.GONE
        }


        // --- Shift & Holiday Display Logic ---
        holder.shiftChar.background = null
        holder.shiftChar.text = ""
        holder.holidayNameSmall.visibility = View.GONE
        holder.shiftChar.textSize = 15f

        // "반월", "반년" (Half-Monthly, Half-Yearly) Special Logic
        // These are overrides or specific shifts that user sets.
        // User requested: "월", "년" text. Half-filled background (Red + Transparent).
        // Check exact string or "startswith" if logic changed? 
        // Logic in adapter `getShift` might return "반월", "반년".

        if (showHolidays && fullHolidayName != null) {
            // Holiday Mode (Priority): Show full holiday name, no circle
            holder.shiftChar.text = fullHolidayName
            holder.shiftChar.setTextColor(Color.parseColor("#FF5252"))
                holder.shiftChar.textSize = 11f
            holder.shiftChar.background = null
        } else if (item.shift != null && item.shift != "비번") {
            // Shift Mode
            
            // Handle specific "Half" cases first
            if (item.shift == "반월" || item.shift == "반년") {
                 holder.shiftChar.text = if (item.shift == "반월") "월" else "년"
                 holder.shiftChar.setTextColor(ContextCompat.getColor(context, R.color.black)) // Black for contrast on Half Red/Transparent
                 holder.shiftChar.textSize = 15f
                 holder.shiftChar.background = ContextCompat.getDrawable(context, R.drawable.bg_shift_half_red)
            } else {
                // Standard Logic
                val shiftAbbreviation = when (item.shift) {
                    "주간" -> "주"
                    "석간" -> "석"
                    "야간" -> "야"
                    "주간 맞교대" -> "주맞"
                    "야간 맞교대" -> "야맞"
                    "휴무", "휴가" -> "휴"
                    "월차" -> "월"
                    "연차" -> "연"
                    "교육" -> "교"
                    else -> item.shift.take(1)
                }
                holder.shiftChar.text = shiftAbbreviation
                holder.shiftChar.textSize = 17f
                holder.shiftChar.setTypeface(null, android.graphics.Typeface.BOLD)

                val shiftColorRes = when (item.shift) {
                    "주간" -> R.color.shift_lemon
                    "석간" -> R.color.shift_seok
                    "야간" -> R.color.shift_ya
                    "주간 맞교대" -> R.color.shift_jumat
                    "야간 맞교대" -> R.color.shift_yamat
                    "휴무", "휴가", "월차", "연차" -> R.color.shift_red
                    "교육" -> R.color.primary
                    else -> R.color.text_secondary
                }
                val shiftColor = ContextCompat.getColor(context, shiftColorRes)

                if (isToday) {
                    // Today: Solid Circle
                    val background = ContextCompat.getDrawable(context, R.drawable.bg_shift_solid_v4) as? android.graphics.drawable.GradientDrawable
                    background?.setColor(shiftColor)
                    holder.shiftChar.background = background
                    holder.shiftChar.backgroundTintList = null 
                    
                    if (item.shift == "주간" || item.shift == "석간") {
                        holder.shiftChar.setTextColor(ContextCompat.getColor(context, R.color.black))
                    } else {
                        holder.shiftChar.setTextColor(Color.WHITE)
                    }
                } else {
                    // Not Today: Stroke Circle
                    val background = ContextCompat.getDrawable(context, R.drawable.bg_shift_stroke_v4) as? android.graphics.drawable.GradientDrawable
                    background?.setStroke(dpToPx(context, 1.5f), shiftColor)
                    background?.setColor(Color.TRANSPARENT)
                    
                    holder.shiftChar.background = background
                    holder.shiftChar.backgroundTintList = null 
                    
                    holder.shiftChar.setTextColor(shiftColor)
                }
            }
        }

        // Lunar date small display if requested or just default
        if (!showHolidays && fullHolidayName != null) {
            holder.holidayNameSmall.visibility = View.VISIBLE
            holder.holidayNameSmall.text = fullHolidayName
        } else {
            // Ensure visibility GONE if not needed (e.g. standard day)
             holder.holidayNameSmall.visibility = View.GONE
        }

        // Double check: if showHolidays=true (Holiday mode), we handled it at top block.
        // But if showHolidays=true and NO holiday, we show lunar date? 
        // User asked: "Overlap date and holiday text". 
        // My item_day.xml has holidayNameSmall at bottom now.
        // If showHolidays=true, CalendarAdapter usually HIDES shiftChar and shows Holiday Name?
        // Wait, standard logic (lines 84-91 above):
        // If showHolidays && fullHolidayName != null -> shiftChar shows Name.
        // If showHolidays && fullHolidayName == null -> shiftChar shows LUNAR DATE? (Old logic had this).
        
        if (showHolidays && fullHolidayName == null) {
             // Show Lunar Date in shiftChar instead of empty?
             // Or shiftChar is empty, show small text?
             // Previous code:
             // holder.shiftChar.text = "" 
             // holder.holidayNameSmall.visibility = View.VISIBLE
             // holder.holidayNameSmall.text = HolidayManager.getLunarDateString(item.date)
             
             holder.shiftChar.text = HolidayManager.getLunarDateString(item.date)
             holder.shiftChar.textSize = 11f
             holder.shiftChar.setTextColor(ContextCompat.getColor(context, R.color.text_tertiary))
             holder.shiftChar.background = null
        }


        // Memo Indicator
        holder.memoIndicator.visibility = View.GONE // Hide indicator, showing text instead
        if (item.hasMemo && !item.memoContent.isNullOrEmpty()) {
            holder.memoContent.visibility = View.VISIBLE
            holder.memoContent.text = item.memoContent
        } else {
            holder.memoContent.visibility = View.GONE
        }

        // Today Border or Highlight
        if (isToday) {
            holder.root.setBackgroundResource(R.drawable.bg_grid_cell_today_v4)
        } else {
            holder.root.setBackgroundResource(R.drawable.bg_grid_cell_v4)
        }

        holder.itemView.setOnClickListener {
            if (item.date != null && item.shift != null) {
                listener.onDayClick(item.date, item.shift)
            }
        }
    }

    override fun getItemCount(): Int = days.size
}