from __future__ import annotations

import random
from dataclasses import dataclass
from typing import Dict, List, Tuple

import pygame

from config import constants

ItemType = str


@dataclass
class ItemSpec:
    color: Tuple[int, int, int]
    label: str


ITEM_SPECS: Dict[ItemType, ItemSpec] = {
    # Metals (asteroids)
    "steel_scrap": ItemSpec((160, 160, 160), "Stl"),
    "aluminum_sheet": ItemSpec((180, 200, 220), "Al"),
    "copper_wire": ItemSpec((200, 140, 90), "Cu"),
    # Enemy drops
    "lithium_battery": ItemSpec((140, 200, 255), "Li"),
    "circuit_board": ItemSpec((90, 200, 120), "PCB"),
    "rare_earth_element": ItemSpec((200, 160, 255), "REE"),
    "pet_plastic": ItemSpec((200, 200, 220), "PET"),
    "carbon_fiber": ItemSpec((80, 80, 90), "CF"),
    "titanium_alloy": ItemSpec((170, 170, 190), "Ti"),
    "power_core": ItemSpec((255, 100, 80), "Core"),
    "crystal_capacitor": ItemSpec((180, 220, 255), "Cap"),
    "exotic_isotope": ItemSpec((255, 180, 80), "Iso"),
    # Health
    "repair_nanites": ItemSpec((90, 240, 140), "Heal"),
    "bio_gel": ItemSpec((90, 200, 90), "Gel"),
    # Power-ups (enemy drops)
    "powerup_magnet": ItemSpec((90, 200, 255), "Mag"),
    "powerup_super_magnet": ItemSpec((110, 220, 255), "SMag"),
    "powerup_weapon_missile": ItemSpec((255, 190, 80), "MSL"),
    "powerup_weapon_plasma": ItemSpec((120, 200, 255), "PLS"),
    "powerup_weapon_ray": ItemSpec((255, 120, 200), "RAY"),
    "powerup_shieldgen": ItemSpec((140, 220, 255), "SHD"),
    "powerup_rapidfire": ItemSpec((255, 220, 90), "RF"),
    "powerup_damage": ItemSpec((255, 120, 120), "Dmg"),
    "powerup_shield": ItemSpec((120, 180, 255), "Shd"),
    "powerup_regen": ItemSpec((90, 240, 140), "Regen"),
    "powerup_slow": ItemSpec((120, 180, 255), "Slow"),
    "powerup_multishot": ItemSpec((255, 160, 255), "2x"),
}


def random_metal_drop() -> ItemType:
    r = random.random()
    cumulative = 0.0
    table = constants.ASTEROID_METAL_DROP_TABLE
    for name, prob in table:
        cumulative += prob
        if r <= cumulative:
            return name
    return table[-1][0]


def random_enemy_drop() -> ItemType:
    table = constants.ENEMY_DROP_TABLE
    total = sum(weight for _, weight in table)
    r = random.uniform(0, total)
    cumulative = 0.0
    for name, weight in table:
        cumulative += weight
        if r <= cumulative:
            return name
    return table[-1][0]


def random_powerup_drop() -> ItemType:
    table = constants.POWERUP_DROP_TABLE
    total = sum(weight for _, weight in table)
    r = random.uniform(0, total)
    cumulative = 0.0
    for name, weight in table:
        cumulative += weight
        if r <= cumulative:
            return name
    return table[-1][0]


class Item(pygame.sprite.Sprite):
    """Collectible item dropped from asteroids or enemies."""

    ICONS: Dict[str, pygame.Surface] = {}

    def __init__(self, item_type: ItemType, pos: Tuple[float, float]):
        super().__init__()
        spec = ITEM_SPECS.get(item_type, ItemSpec((200, 200, 200), item_type))
        self.item_type = item_type
        icon = self.ICONS.get(item_type)
        if icon:
            self.image = pygame.transform.scale(icon, (18, 18))
        else:
            self.image = pygame.Surface((14, 14), pygame.SRCALPHA)
            self.image.fill(spec.color)
            font = pygame.font.Font(None, 12)
            text = font.render(spec.label, True, (0, 0, 0))
            text_rect = text.get_rect(center=(7, 7))
            self.image.blit(text, text_rect)
        self.rect = self.image.get_rect(center=pos)
        self.pos = pygame.Vector2(pos)
        self.vel = pygame.Vector2(-80, random.uniform(-20, 20))  # drift left with slight variation

    def update(self, dt: float):
        self.pos += self.vel * dt
        self.rect.center = (int(self.pos.x), int(self.pos.y))


class Inventory:
    """Simple inventory with capacity counting total items."""

    def __init__(self, capacity: int = constants.INVENTORY_LIMIT):
        self.capacity = capacity
        self.counts: Dict[ItemType, int] = {}
        self.weapons: Dict[str, int] = {}
        self.upgrades: Dict[str, int] = {}
        self.owned_ships = {"salvager_one"}
        self.current_ship = "salvager_one"

    @property
    def total(self) -> int:
        return sum(self.counts.values())

    def can_pick(self, amount: int = 1) -> bool:
        return True  # unlimited inventory

    def add(self, item_type: ItemType, amount: int = 1) -> bool:
        if not self.can_pick(amount):
            return False
        self.counts[item_type] = self.counts.get(item_type, 0) + amount
        return True

    def get(self, item_type: ItemType) -> int:
        # Allow checking crafted weapons using snake_case keys for recipes
        weapon_key_map = {
            "laser_cannon": "Laser Cannon",
            "missile_launcher": "Missile Launcher",
            "shield_generator": "Shield Generator",
            "plasma_weapon": "Plasma Weapon",
            "destruction_ray": "Destruction Ray",
        }
        if item_type in weapon_key_map:
            return self.weapons.get(weapon_key_map[item_type], 0)
        return self.counts.get(item_type, 0)

    def add_weapon(self, weapon_name: str):
        self.weapons[weapon_name] = self.weapons.get(weapon_name, 0) + 1

    def remove_weapon(self, weapon_name: str):
        if weapon_name not in self.weapons:
            return
        self.weapons[weapon_name] = max(0, self.weapons.get(weapon_name, 0) - 1)
        if self.weapons[weapon_name] <= 0:
            del self.weapons[weapon_name]