#include "game/map/map.hpp"

#include <fstream>
#include <iostream>
#include <stdexcept>

#include "core/rendering/screen.hpp"
#include "core/resources/resource_cache.hpp"
#include "external/fkyaml_node.hpp"
#include "utils/defines.hpp"

namespace {

    // AABB amb inequitat estricta: dos rects que es toquen exactament (la
    // cantonada o una vora al píxel) NO es consideren intersecció. SDL3
    // SDL_HasRectIntersectionFloat tracta el toc com a intersecció, cosa
    // que bloqueja el moviment als encreuaments del nostre laberint.
    auto overlapStrict(const SDL_FRect& a, const SDL_FRect& b) -> bool {
        return (a.x + a.w) > b.x && (b.x + b.w) > a.x && (a.y + a.h) > b.y && (b.y + b.h) > a.y;
    }

}  // namespace

void Map::loadFrom(const std::string& yaml_path) {
    std::ifstream file(yaml_path);
    if (!file.is_open()) {
        throw std::runtime_error("Map: no s'ha pogut obrir " + yaml_path);
    }
    auto yaml = fkyaml::node::deserialize(file);
    if (!yaml.contains("geometry")) {
        throw std::runtime_error("Map: manca bloc `geometry:` a " + yaml_path);
    }
    const auto& g = yaml["geometry"];

    grid_cols = g["grid_cols"].get_value<int>();
    grid_rows = g["grid_rows"].get_value<int>();
    sarc_w = g["sarc_w"].get_value<int>();
    sarc_h = g["sarc_h"].get_value<int>();
    pitch_x = g["pitch_x"].get_value<int>();
    pitch_y = g["pitch_y"].get_value<int>();
    hud_h = g["hud_h"].get_value<int>();
    back_wall_h = g["back_wall_h"].get_value<int>();
    side_wall_w = g["side_wall_w"].get_value<int>();

    // Derivats: el passadís és el sobrant del pitch sobre el sarcòfag, i
    // l'exterior reutilitza la mateixa amplada per mantenir el pas lliure.
    corridor_w = pitch_x - sarc_w;
    corridor_h = pitch_y - sarc_h;
    outer_corridor = corridor_w;

    board_w = ((grid_cols - 1) * pitch_x) + sarc_w;
    board_h = ((grid_rows - 1) * pitch_y) + sarc_h;

    origin_x = side_wall_w + outer_corridor;
    origin_y = hud_h + back_wall_h + outer_corridor;

    playfield_x = side_wall_w;
    playfield_y = hud_h + back_wall_h;
    playfield_w = board_w + (2 * outer_corridor);
    playfield_h = board_h + (2 * outer_corridor);

    std::cout << "Map: geometria " << grid_cols << "x" << grid_rows
              << " sarcs " << sarc_w << "x" << sarc_h
              << " pitch " << pitch_x << "x" << pitch_y
              << " des de " << yaml_path << '\n';
}

auto Map::getSarcRowBottomY(int row) -> int {
    return origin_y + (row * pitch_y) + sarc_h;
}

auto Map::getSarcRect(int col, int row) -> SDL_FRect {
    return {
        .x = static_cast<float>(origin_x + (col * pitch_x)),
        .y = static_cast<float>(origin_y + (row * pitch_y)),
        .w = static_cast<float>(sarc_w),
        .h = static_cast<float>(sarc_h),
    };
}

void Map::renderBackground() {
    auto& screen = Screen::get();
    const auto& palette = Resource::Cache::get().getPalette("ui");

    // Comencem pintant el sòl a tota la pantalla; després tapem marcador i
    // murs. Els rectangles dels murs s'encavalquen a les cantonades: no
    // importa perquè són del mateix color.
    screen.fillRect(0, 0, GameCanvas::WIDTH, GameCanvas::HEIGHT, palette[FLOOR]);

    // Marcador (dalt).
    screen.fillRect(0, 0, GameCanvas::WIDTH, hud_h, palette[HUD_BG]);

    // Mur posterior: banda horitzontal sota el marcador.
    screen.fillRect(0, hud_h, GameCanvas::WIDTH, back_wall_h, palette[WALL]);

    // Murs laterals (des del marcador fins al final).
    screen.fillRect(0, hud_h, side_wall_w, GameCanvas::HEIGHT - hud_h, palette[WALL]);
    screen.fillRect(GameCanvas::WIDTH - side_wall_w, hud_h, side_wall_w, GameCanvas::HEIGHT - hud_h, palette[WALL]);

    // Mur frontal: de la vora inferior del passadís de baix fins al final del
    // canvas. Assumeix els 40 px extra de 320×240 i fa de primer pla.
    const int FRONT_WALL_Y = origin_y + board_h + outer_corridor;
    screen.fillRect(0, FRONT_WALL_Y, GameCanvas::WIDTH, GameCanvas::HEIGHT - FRONT_WALL_Y, palette[WALL]);
}

void Map::renderSarcsRow(int row) {
    auto& screen = Screen::get();
    const auto& palette = Resource::Cache::get().getPalette("ui");
    const int Y = origin_y + (row * pitch_y);
    for (int col = 0; col < grid_cols; ++col) {
        const int X = origin_x + (col * pitch_x);
        screen.fillRect(X, Y, sarc_w, sarc_h, palette[SARC]);
    }
}

auto Map::collides(const SDL_FRect& base_box) -> bool {
    // Recorregut trivial dels sarcòfags. Amb una graella petita no val la
    // pena indexar per col/row prèviament; si algun dia creix, es pot
    // calcular el rang de columnes/files candidates a partir de base_box.
    for (int row = 0; row < grid_rows; ++row) {
        for (int col = 0; col < grid_cols; ++col) {
            if (overlapStrict(base_box, getSarcRect(col, row))) { return true; }
        }
    }
    return false;
}