package model

import korlibs.math.*
import korlibs.time.*
import kotlin.jvm.*
import kotlin.math.*

data class Battler (
    val id: Id,

    private var _name: String,
    private var _composure: Double,
    private var _health: Double,
    private var _maxHealth: Double,
    private var _energy: Double,
    private var _stamina: Double,
    private var _maxStamina: Double,

    private var _shaken: Boolean = false,
    private var _shakenTimes: Int = 0,
    private var _composurePausedUntil: TimeSpan = TimeSpan.ZERO,
    private var _energyPausedUntil: TimeSpan = TimeSpan.ZERO,
    private var _currentUpdate: TimeSpan = TimeSpan.ZERO,

    private var lastUpdate: TimeSpan = TimeSpan.ZERO,
    private var lastShaken: Boolean = _shaken,
    private var lastComposure: Double = _composure,
    private var lastEnergy: Double = _energy,
    private var lastStamina: Double = _stamina,
) {
    @JvmInline
    value class Id(val v: Int)

    class Editable (private val battler: Battler){
        val id: Id get() = battler.id
        var name: String get() = battler.name
            set(v) { battler._name = v }
        var composure: Double get() = battler.composure
            set(v) { battler._composure = v }
        var health: Double get() = battler.health
            set(v) { battler._health = v }
        var maxHealth: Double get() = battler.maxHealth
            set(v) { battler._maxHealth = v }
        var energy: Double get() = battler.energy
            set(v) { battler._energy = v }
        var stamina: Double get() = battler.stamina
            set(v) { battler._stamina = v }
        var maxStamina: Double get() = battler.maxStamina
            set(v) { battler._maxStamina = v }
        var shaken: Boolean get() = battler.shaken
            set(v) { battler._shaken = v }
        var shakenTimes: Int get() = battler.shakenTimes
            set(v) { battler._shakenTimes = v }
        var composurePausedUntil: TimeSpan get() = battler.composurePausedUntil
            set(v) { battler._composurePausedUntil = v }
        var energyPausedUntil: TimeSpan get() = battler.energyPausedUntil
            set(v) { battler._energyPausedUntil = v }
        val currentUpdate: TimeSpan get() = battler.currentUpdate

        fun becomeShaken() {
            composure = health.coerceAtMost(0.0)
            if (shaken) {
                return
            }
            composurePausedUntil = (currentUpdate + battler.composureRecoveryDelay).coerceAtLeast(composurePausedUntil)
            shaken = true
            shakenTimes += 1
        }

        fun inflictComposureDamage(damage: Double) {
            if (shaken) {
                return
            }
            composurePausedUntil =
                (currentUpdate + battler.composureChargeDelay).coerceAtLeast(composurePausedUntil)
            composure -= damage
            if (composure <= 0) {
                becomeShaken()
            }
        }

        fun inflictHealthDamage(damage: Double) {
            composurePausedUntil = (currentUpdate + battler.composureRecoveryDelay).coerceAtLeast(composurePausedUntil)
            health -= damage
            composure -= damage
            if (composure <= 0) {
                becomeShaken()
            }
        }

        fun spendEnergy(cost: Double) {
            energyPausedUntil = (currentUpdate + battler.energyChargeDelay).coerceAtLeast(energyPausedUntil)
            energy = (energy - cost).coerceAtLeast(0.0)
        }

        fun spendStamina(cost: Double) {
            energyPausedUntil = (currentUpdate + battler.energyChargeDelay).coerceAtLeast(energyPausedUntil)
            stamina = (stamina - cost).coerceAtLeast(0.0)
            energy = (energy - cost).coerceAtLeast(0.0)
        }
    }

    val name: String get() = _name
    val composure: Double get() = _composure
    val health: Double get() = _health
    val maxHealth: Double get() = _maxHealth
    val energy: Double get() = _energy
    val stamina: Double get() = _stamina
    val maxStamina: Double get() = _maxStamina
    val shaken: Boolean get() = _shaken
    val shakenTimes: Int get() = _shakenTimes
    val composurePausedUntil: TimeSpan get() = _composurePausedUntil
    val energyPausedUntil: TimeSpan get() = _energyPausedUntil
    val currentUpdate: TimeSpan get() = _currentUpdate

    private val composureChargeTime: TimeSpan get() = TimeSpan(45_000.0 * 1.2.pow(shakenTimes - 1))
    private val composureChargeDelay: TimeSpan get() = TimeSpan(2_000.0 * 1.2.pow(shakenTimes - 1))
    private val composureRecoveryTime: TimeSpan get() = TimeSpan(7_000.0 * 1.2.pow(shakenTimes - 1))
    private val composureRecoveryDelay: TimeSpan get() = TimeSpan(3_000.0 * 1.2.pow(shakenTimes - 1))

    private val composureChargeCoefficient: Double get() = health / composureChargeTime.milliseconds.squared()

    private val energyChargeTime: TimeSpan get() = TimeSpan(30_000.0)
    private val energyChargeDelay: TimeSpan get() = TimeSpan(1_000.0)
    private val staminaChargeTime: TimeSpan get() = TimeSpan(300_000.0)

    private fun advanceComposureTo(t: TimeSpan) {
        var dtComposure = if (lastUpdate < composurePausedUntil) {
            if (t > composurePausedUntil) {
                t - composurePausedUntil
            } else {
                TimeSpan.ZERO
            }
        } else {
            t - lastUpdate
        }
        if (lastShaken && dtComposure.isPositive() && health > 0) {
            val halfHealth = health/2.0
            val dtRecover = composureRecoveryTime * (halfHealth - lastComposure.coerceAtLeast(0.0)) / halfHealth
            if (dtComposure > dtRecover) {
                _composure = halfHealth
                _shaken = false
                dtComposure -= dtRecover
            } else {
                _composure = (
                    lastComposure.coerceAtLeast(0.0) + dtComposure.milliseconds * halfHealth / composureRecoveryTime.milliseconds)
                _shaken = lastShaken
                dtComposure = TimeSpan.ZERO
            }
        } else {
            _composure = lastComposure
            _shaken = lastShaken
        }
        if (dtComposure.isPositive()) {
            if (health > 0) {
                val lastChargeTime = TimeSpan(
                    sqrt(4 * composureChargeCoefficient * composure) / (2 * composureChargeCoefficient)
                )
                _composure = if (dtComposure + lastChargeTime >= composureChargeTime) {
                    health
                } else {
                    (composureChargeCoefficient * (lastChargeTime + dtComposure).milliseconds.squared())
                }
            } else {
                _composure = health
            }
        }
    }

    private fun advanceEnergyAndStaminaTo(t: TimeSpan) {
        var dtEnergy = if (lastUpdate < energyPausedUntil) {
            if (t > energyPausedUntil) {
                t - energyPausedUntil
            } else {
                TimeSpan.ZERO
            }
        } else {
            t - lastUpdate
        }
        if (dtEnergy.isPositive()) {
            if (lastEnergy < lastStamina) {
                if (lastStamina > 0) {
                    val dtToFull = energyChargeTime * (lastStamina - lastEnergy) / lastStamina
                    if (dtEnergy >= dtToFull) {
                        _energy = lastStamina
                        dtEnergy -= dtToFull
                    } else {
                        _energy = lastEnergy + (lastStamina * dtEnergy.milliseconds) / energyChargeTime.milliseconds
                        dtEnergy = TimeSpan.ZERO
                    }
                } else {
                    _energy = lastStamina
                }
            }
            if (dtEnergy.isPositive() && lastStamina < maxStamina) {
                _stamina = min(
                    maxStamina,
                    lastStamina + (maxStamina * dtEnergy.milliseconds) / staminaChargeTime.milliseconds)
                _energy = stamina
            }
        }
    }

    fun advanceTo(t: TimeSpan) {
        _currentUpdate = t
        if (composure < health) {
            advanceComposureTo(t)
        }
        if (energy < stamina || stamina < maxStamina) {
            advanceEnergyAndStaminaTo(t)
        }
    }

    fun updateAt(t: TimeSpan, block: Editable.() -> Unit) {
        advanceTo(t)

        block(Editable(this))

        lastUpdate = currentUpdate
        lastShaken = shaken
        lastComposure = composure
        lastEnergy = energy
        lastStamina = stamina
    }

    val asSaved: Saved get() = Saved(
        id = id,

        name = name,
        composure = composure,
        health = health,
        maxHealth = maxHealth,
        energy = energy,
        stamina = stamina,
        maxStamina = maxStamina,

        shaken = shaken,
        shakenTimes = shakenTimes,
        composurePausedUntil = composurePausedUntil,
        energyPausedUntil = energyPausedUntil
    )

    fun revertTo(previous: Saved, at: TimeSpan) {
        _name = previous.name
        _composure = previous.composure
        _health = previous.health
        _maxHealth = previous.maxHealth
        _energy = previous.energy
        _stamina = previous.stamina
        _maxStamina = previous.maxStamina

        _shaken = previous.shaken
        _shakenTimes = previous.shakenTimes
        _composurePausedUntil = previous.composurePausedUntil
        _energyPausedUntil = previous.energyPausedUntil

        _currentUpdate = at
        lastUpdate = at
        lastShaken = previous.shaken
        lastComposure = previous.composure
        lastEnergy = previous.energy
        lastStamina = previous.stamina
    }

    constructor(saved: Saved, at: TimeSpan) : this(
        id = saved.id,

        _name = saved.name,
        _composure = saved.composure,
        _health = saved.health,
        _maxHealth = saved.maxHealth,
        _energy = saved.energy,
        _stamina = saved.stamina,
        _maxStamina = saved.maxStamina,

        _shaken = saved.shaken,
        _shakenTimes = saved.shakenTimes,
        _composurePausedUntil = saved.composurePausedUntil,
        _energyPausedUntil = saved.energyPausedUntil,

        _currentUpdate = at,
        lastUpdate = at,
        lastShaken = saved.shaken,
        lastComposure = saved.composure,
        lastEnergy = saved.energy,
        lastStamina = saved.stamina,
    )

    data class Saved(
        val id: Id,

        val name: String,
        val composure: Double,
        val health: Double = composure,
        val maxHealth: Double = health,
        val energy: Double,
        val stamina: Double = energy,
        val maxStamina: Double = stamina,

        val shaken: Boolean = false,
        val shakenTimes: Int = 0,
        val composurePausedUntil: TimeSpan = TimeSpan.ZERO,
        val energyPausedUntil: TimeSpan = TimeSpan.ZERO,
    )

    val asReadonly get() = Readonly(this)

    class Readonly (private val battler: Battler) {
        val id: Id get() = battler.id
        val name: String get() = battler.name
        val composure: Double get() = battler.composure
        val health: Double get() = battler.health
        val maxHealth: Double get() = battler.maxHealth
        val energy: Double get() = battler.energy
        val stamina: Double get() = battler.stamina
        val maxStamina: Double get() = battler.maxStamina
        val shaken: Boolean get() = battler.shaken
        val shakenTimes: Int get() = battler.shakenTimes
        val composurePausedUntil: TimeSpan get() = battler.composurePausedUntil
        val energyPausedUntil: TimeSpan get() = battler.energyPausedUntil
        val currentUpdate: TimeSpan get() = battler.currentUpdate
        val asSaved: Saved get() = battler.asSaved
    }
}