package com.taf.attendance

import android.app.DatePickerDialog
import android.os.Bundle
import android.widget.ArrayAdapter
import android.widget.ListView
import android.widget.TextView
import androidx.appcompat.app.AppCompatActivity
import androidx.lifecycle.lifecycleScope
import com.prolificinteractive.materialcalendarview.CalendarDay
import com.prolificinteractive.materialcalendarview.MaterialCalendarView
import androidx.core.content.ContextCompat
import com.taf.attendance.decorators.RangeDayDecorator
import com.taf.attendance.data.AttendanceRepository
import com.taf.attendance.model.AttendanceRecord
import kotlinx.coroutines.launch
import java.text.DateFormat
import java.util.Calendar
import java.util.Date

class HoursActivity : AppCompatActivity() {
    private lateinit var repo: AttendanceRepository
    private lateinit var calendar: MaterialCalendarView
    private var rangeStart: Long = 0L
    private var rangeEnd: Long = 0L
    private var rangeDecorator: RangeDayDecorator? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_hours)
        repo = AttendanceRepository(this)

        calendar = findViewById(R.id.calendarView)
        val details = findViewById<ListView>(R.id.detailsList)
        val totalText = findViewById<TextView>(R.id.totalText)

        // allow selecting a single day directly from the calendar
        calendar.selectionMode = MaterialCalendarView.SELECTION_MODE_SINGLE

        // show and select today by default
        val today = Calendar.getInstance()
        calendar.selectedDate = CalendarDay.from(today)
        updateDay(today.timeInMillis, details, totalText)

        calendar.setOnDateChangedListener { _, date, _ ->
            val cal = Calendar.getInstance()
            cal.set(date.year, date.month - 1, date.day, 0, 0, 0)
            updateDay(cal.timeInMillis, details, totalText)
        }

        findViewById<TextView>(R.id.startPicker).setOnClickListener {
            showDatePicker { date ->
                rangeStart = date
                updateRange(totalText)
                updateCalendarRange()
            }
        }

        findViewById<TextView>(R.id.endPicker).setOnClickListener {
            showDatePicker { date ->
                rangeEnd = date
                updateRange(totalText)
                updateCalendarRange()
            }
        }
    }

    private fun showDatePicker(onDate: (Long) -> Unit) {
        val now = Calendar.getInstance()
        DatePickerDialog(this, { _, y, m, d ->
            val cal = Calendar.getInstance()
            cal.set(y, m, d, 0, 0, 0)
            onDate(cal.timeInMillis)
        }, now.get(Calendar.YEAR), now.get(Calendar.MONTH), now.get(Calendar.DAY_OF_MONTH)).show()
    }

    private fun updateDay(dayStart: Long, list: ListView, text: TextView) {
        val cal = Calendar.getInstance()
        cal.timeInMillis = dayStart
        cal.set(Calendar.HOUR_OF_DAY, 0)
        cal.set(Calendar.MINUTE, 0)
        cal.set(Calendar.SECOND, 0)
        val start = cal.timeInMillis
        cal.set(Calendar.HOUR_OF_DAY, 23)
        cal.set(Calendar.MINUTE, 59)
        cal.set(Calendar.SECOND, 59)
        val end = cal.timeInMillis
        lifecycleScope.launch {
            val records = repo.history(start, end)
            displayRecords(records, list, text)
        }
    }

    private fun updateRange(text: TextView) {
        if (rangeStart == 0L || rangeEnd == 0L) return
        var start = rangeStart
        var end = rangeEnd
        if (start > end) {
            val tmp = start
            start = end
            end = tmp
        }
        lifecycleScope.launch {
            val records = repo.history(start, end)
            val hours = calculateHours(records)
            text.text = String.format("Selected Range Hours: %.2f", hours)
        }
    }

    private fun updateCalendarRange() {
        if (rangeStart == 0L || rangeEnd == 0L) return
        var start = rangeStart
        var end = rangeEnd
        if (start > end) {
            val tmp = start
            start = end
            end = tmp
        }
        rangeDecorator?.let { calendar.removeDecorator(it) }
        val startDay = CalendarDay.from(Date(start))
        val endDay = CalendarDay.from(Date(end))
        val drawable = ContextCompat.getDrawable(this, R.drawable.range_selector_background)!!
        rangeDecorator = RangeDayDecorator(startDay, endDay, drawable)
        calendar.addDecorator(rangeDecorator!!)
    }

    private suspend fun displayRecords(records: List<AttendanceRecord>, list: ListView, text: TextView) {
        val adapter = ArrayAdapter(this, android.R.layout.simple_list_item_1,
            records.map { "${it.type} - ${DateFormat.getTimeInstance().format(Date(it.time))}" })
        list.adapter = adapter
        val hours = calculateHours(records)
        text.text = String.format("Hours: %.2f", hours)
    }

    private fun calculateHours(records: List<AttendanceRecord>): Double {
        var total = 0L
        var lastIn: Long? = null
        for (rec in records.sortedBy { it.time }) {
            if (rec.type == "in") {
                lastIn = rec.time
            } else if (rec.type == "out" && lastIn != null) {
                total += rec.time - lastIn!!
                lastIn = null
            }
        }
        return total / 3600000.0
    }
}