defmodule Odinsea.Constants.Game do
  @moduledoc """
  Game constants ported from Java GameConstants.
  These define gameplay mechanics, limits, and rates.
  """

  # Character limits
  @max_level 250
  @max_ap 999
  @max_hp_mp 999_999
  @base_max_hp 50
  @base_max_mp 50

  # Inventory limits
  @max_inventory_slots 128
  @equip_slots 96
  @use_slots 96
  @setup_slots 96
  @etc_slots 96
  @cash_slots 96

  # Meso limits
  @max_meso 9_999_999_999
  @max_storage_meso 9_999_999_999

  # Guild limits
  @max_guild_name_length 12
  @max_guild_members 100

  # Party limits
  @max_party_members 6
  @max_expedition_members 30

  # GMS specific flag
  @gms true

  @doc """
  Returns the maximum character level.
  """
  def max_level, do: @max_level

  @doc """
  Returns the maximum AP.
  """
  def max_ap, do: @max_ap

  @doc """
  Returns the maximum HP/MP.
  """
  def max_hp_mp, do: @max_hp_mp

  @doc """
  Returns the base max HP for new characters.
  """
  def base_max_hp, do: @base_max_hp

  @doc """
  Returns the base max MP for new characters.
  """
  def base_max_mp, do: @base_max_mp

  @doc """
  Returns the max inventory slots per type.
  """
  def max_inventory_slots, do: @max_inventory_slots

  def equip_slots, do: @equip_slots
  def use_slots, do: @use_slots
  def setup_slots, do: @setup_slots
  def etc_slots, do: @etc_slots
  def cash_slots, do: @cash_slots

  @doc """
  Returns the max meso a character can hold.
  """
  def max_meso, do: @max_meso

  @doc """
  Returns the max meso in storage.
  """
  def max_storage_meso, do: @max_storage_meso

  @doc """
  Returns true if this is a GMS server.
  """
  def gms?, do: @gms

  @doc """
  Returns the rates from configuration.
  """
  def rates do
    Application.get_env(:odinsea, :rates, [])
  end

  @doc """
  Returns the EXP rate.
  """
  def exp_rate do
    rates()[:exp] || 1
  end

  @doc """
  Returns the meso rate.
  """
  def meso_rate do
    rates()[:meso] || 1
  end

  @doc """
  Returns the drop rate.
  """
  def drop_rate do
    rates()[:drop] || 1
  end

  # Job classification helpers

  @doc """
  Returns true if the job is a beginner job.
  """
  def beginner?(job), do: div(job, 1000) == 0 && rem(job, 100) == 0

  @doc """
  Returns true if the job is a warrior class.
  """
  def warrior?(job), do: div(job, 100) == 1

  @doc """
  Returns true if the job is a magician class.
  """
  def magician?(job), do: div(job, 100) == 2

  @doc """
  Returns true if the job is a bowman class.
  """
  def bowman?(job), do: div(job, 100) == 3

  @doc """
  Returns true if the job is a thief class.
  """
  def thief?(job), do: div(job, 100) == 4

  @doc """
  Returns true if the job is a pirate class.
  """
  def pirate?(job), do: div(job, 100) == 5 || div(job, 100) == 51 || div(job, 100) == 52

  @doc """
  Returns true if the job is a resistance class.
  """
  def resistance?(job), do: div(job, 1000) == 3

  @doc """
  Returns true if the job is a cygnus class.
  """
  def cygnus?(job), do: div(job, 1000) == 1

  @doc """
  Returns true if the job is an aran.
  """
  def aran?(job), do: div(job, 100) == 21

  @doc """
  Returns true if the job is an evan.
  """
  def evan?(job), do: div(job, 100) == 22 || job == 2001

  @doc """
  Returns the job name for a given job ID.
  """
  def job_name(job) do
    case job do
      0 -> "Beginner"
      100 -> "Warrior"
      110 -> "Fighter"
      120 -> "Page"
      130 -> "Spearman"
      111 -> "Crusader"
      121 -> "Knight"
      131 -> "Dragon Knight"
      112 -> "Hero"
      122 -> "Paladin"
      132 -> "Dark Knight"
      200 -> "Magician"
      210 -> "Wizard (F/P)"
      220 -> "Wizard (I/L)"
      230 -> "Cleric"
      211 -> "Mage (F/P)"
      221 -> "Mage (I/L)"
      231 -> "Bishop"
      212 -> "Arch Mage (F/P)"
      222 -> "Arch Mage (I/L)"
      232 -> "Arch Mage"
      300 -> "Bowman"
      310 -> "Hunter"
      320 -> "Crossbowman"
      311 -> "Ranger"
      321 -> "Sniper"
      312 -> "Bowmaster"
      322 -> "Marksman"
      400 -> "Thief"
      410 -> "Assassin"
      420 -> "Bandit"
      411 -> "Hermit"
      421 -> "Chief Bandit"
      412 -> "Night Lord"
      422 -> "Shadower"
      500 -> "Pirate"
      510 -> "Brawler"
      520 -> "Gunslinger"
      511 -> "Marauder"
      521 -> "Outlaw"
      512 -> "Buccaneer"
      522 -> "Corsair"
      1000 -> "Noblesse"
      1100 -> "Dawn Warrior"
      1200 -> "Blaze Wizard"
      1300 -> "Wind Archer"
      1400 -> "Night Walker"
      1500 -> "Thunder Breaker"
      2000 -> "Legend"
      2100 -> "Aran"
      2001 -> "Evan"
      2002 -> "Mercedes"
      _ -> "Unknown"
    end
  end

  # =============================================================================
  # Skill & Attack Constants (for Anti-Cheat)
  # =============================================================================

  @doc """
  Returns the attack delay for a skill (in ticks).
  Used for speed hack detection.
  """
  def get_attack_delay(skill_id) do
    if skill_id == 0 do
      # Normal attack delay
      300
    else
      # Get from skill data or use default
      get_skill_delay(skill_id) || 300
    end
  end

  @doc """
  Returns the skill damage percentage.
  """
  def get_skill_damage(skill_id) do
    # Default skill damage, would be loaded from WZ in production
    case skill_id do
      0 -> 100
      # Common skills
      1000 -> 40
      1009 -> 3000
      1020 -> 1
      # Warrior
      1001004 -> 150
      1001005 -> 200
      1101006 -> 180
      # Mage
      2001008 -> 120
      2101004 -> 130
      2201004 -> 130
      # Bowman
      3101005 -> 150
      3201005 -> 150
      # Thief
      4001334 -> 130
      4101005 -> 140
      4201005 -> 140
      # Pirate
      5001002 -> 160
      5101004 -> 150
      5201004 -> 150
      # Aran
      21000002 -> 180
      21100001 -> 190
      _ -> 100
    end
  end

  @doc """
  Returns the attack range for a skill.
  """
  def get_attack_range(skill_id) do
    case skill_id do
      0 -> 100
      # Ranged skills
      3101005 -> 500
      3201005 -> 500
      4001334 -> 250
      4101005 -> 250
      4121007 -> 300
      4201005 -> 150
      4221007 -> 600
      # Melee skills
      _ -> 150
    end
  end

  @doc """
  Returns true if skill is a Mu Lung Dojo skill.
  """
  def is_mulung_skill?(skill_id) do
    skill_id >= 10001000 && skill_id < 10002000
  end

  @doc """
  Returns true if skill is a Pyramid skill.
  """
  def is_pyramid_skill?(skill_id) do
    skill_id >= 1020 && skill_id <= 1022
  end

  @doc """
  Returns true if skill has no delay.
  """
  def is_no_delay_skill?(skill_id) do
    # Skills that bypass attack delay checks
    skill_id in [3101005, 1009, 1020]
  end

  @doc """
  Returns true if skill is a magic charge skill.
  """
  def is_magic_charge_skill?(skill_id) do
    skill_id in [2121001, 2221001, 2321001]
  end

  @doc """
  Returns true if skill is an event skill.
  """
  def is_event_skill?(skill_id) do
    # Skills only usable in specific event maps
    skill_id >= 90001000 && skill_id < 90002000
  end

  @doc """
  Returns the linked Aran skill (for skill linking).
  """
  def get_linked_aran_skill(skill_id) do
    # Handle Aran skill linking
    if div(skill_id, 10000) == 21 do
      # Convert Aran skills to regular warrior equivalents for linking
      base = rem(skill_id, 10000)
      cond do
        base == 1005 -> 1101005
        base == 1004 -> 1101006
        true -> skill_id
      end
    else
      skill_id
    end
  end

  # =============================================================================
  # Private Helpers
  # =============================================================================

  defp get_skill_delay(skill_id) do
    case skill_id do
      0 -> 300
      1000 -> 600
      1004 -> 600
      1005 -> 900
      1001004 -> 960
      1001005 -> 1260
      1101006 -> 1050
      2001008 -> 810
      2101004 -> 810
      2201004 -> 810
      3101005 -> 840
      3201005 -> 840
      4001334 -> 600
      4101005 -> 720
      4201005 -> 720
      5001002 -> 600
      5101004 -> 660
      5201004 -> 660
      _ -> nil
    end
  end
end