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>() {
    var rowHeight: Int = 0
    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 tvShiftSmall: TextView = view.findViewById(R.id.tvShiftSmall)
        val shiftChar: TextView = view.findViewById(R.id.shiftChar)
        val holidayNameSmall: TextView = view.findViewById(R.id.holidayNameSmall)
        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) {
        // Dynamic row height: fit exactly 5 rows, 6th row scrolls
        if (rowHeight > 0) {
            holder.itemView.layoutParams.height = rowHeight
        }

        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()
        val hasMemo = item.hasMemo && !item.memoContent.isNullOrEmpty()

        // 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.tvShiftSmall.visibility = View.GONE
        holder.holidayNameSmall.visibility = View.GONE
        holder.shiftChar.textSize = 18f

        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 = 13f
            holder.shiftChar.background = null
            holder.shiftChar.visibility = View.VISIBLE
        } else if (item.shift != null && item.shift != "비번") {
            // Shift Mode
            val shiftAbbreviation = when (item.shift) {
                "주간" -> "주"
                "석간" -> "석"
                "야간" -> "야"
                "주간 맞교대" -> "주맞"
                "야간 맞교대" -> "야맞"
                "휴무", "휴가" -> "휴"
                "월차" -> "월"
                "연차" -> "연"
                "반월" -> "월"
                "반년" -> "년"
                "교육" -> "교"
                else -> item.shift.take(2)
            }

            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
                "반월", "반년" -> R.color.shift_red
                "교육" -> R.color.primary
                else -> R.color.text_secondary
            }
            val shiftColor = ContextCompat.getColor(context, shiftColorRes)

            if (hasMemo) {
                // When day has a memo: show small shift badge next to day number, hide large center shift circle
                holder.shiftChar.visibility = View.GONE
                holder.tvShiftSmall.visibility = View.VISIBLE
                holder.tvShiftSmall.text = shiftAbbreviation
                holder.tvShiftSmall.textSize = if (shiftAbbreviation.length > 1) 7.5f else 9.5f
                holder.tvShiftSmall.setTypeface(null, android.graphics.Typeface.BOLD)

                if (item.shift == "반월" || item.shift == "반년") {
                    holder.tvShiftSmall.text = if (item.shift == "반월") "월" else "년"
                    holder.tvShiftSmall.setTextColor(ContextCompat.getColor(context, R.color.black))
                    holder.tvShiftSmall.background = ContextCompat.getDrawable(context, R.drawable.bg_shift_half_red)
                } else if (isToday) {
                    val smallBg = ContextCompat.getDrawable(context, R.drawable.bg_shift_solid_v4)?.constantState?.newDrawable()?.mutate() as? android.graphics.drawable.GradientDrawable
                    smallBg?.setColor(shiftColor)
                    holder.tvShiftSmall.background = smallBg
                    holder.tvShiftSmall.setTextColor(if (item.shift == "주간" || item.shift == "석간") ContextCompat.getColor(context, R.color.black) else Color.WHITE)
                } else {
                    val smallBg = ContextCompat.getDrawable(context, R.drawable.bg_shift_stroke_v4)?.constantState?.newDrawable()?.mutate() as? android.graphics.drawable.GradientDrawable
                    smallBg?.setStroke(dpToPx(context, 1.2f), shiftColor)
                    smallBg?.setColor(Color.TRANSPARENT)
                    holder.tvShiftSmall.background = smallBg
                    holder.tvShiftSmall.setTextColor(shiftColor)
                }
            } else {
                // When day has NO memo: standard large centered shift circle
                holder.shiftChar.visibility = View.VISIBLE
                holder.tvShiftSmall.visibility = View.GONE

                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))
                    holder.shiftChar.textSize = 18f
                    holder.shiftChar.background = ContextCompat.getDrawable(context, R.drawable.bg_shift_half_red)
                } else {
                    holder.shiftChar.text = shiftAbbreviation
                    holder.shiftChar.textSize = 20f
                    holder.shiftChar.setTypeface(null, android.graphics.Typeface.BOLD)

                    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 {
            holder.holidayNameSmall.visibility = View.GONE
        }
        
        if (showHolidays && fullHolidayName == null) {
             holder.shiftChar.text = HolidayManager.getLunarDateString(item.date)
             holder.shiftChar.textSize = 13f
             holder.shiftChar.setTextColor(ContextCompat.getColor(context, R.color.text_tertiary))
             holder.shiftChar.background = null
             holder.shiftChar.visibility = View.VISIBLE
        }

        // Memo Content Text (Up to 4 lines in center of day cell)
        if (hasMemo) {
            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
}