#include "pxl8_world.h"

#include <stdlib.h>
#include <string.h>

#include "pxl8_bsp.h"
#include "pxl8_macros.h"
#include "pxl8_procgen.h"

struct pxl8_world {
    pxl8_bsp bsp;
    bool loaded;
    bool wireframe;
    u32 wireframe_color;
};

pxl8_world* pxl8_world_create(void) {
    pxl8_world* world = (pxl8_world*)calloc(1, sizeof(pxl8_world));
    if (!world) {
        pxl8_error("Failed to allocate world");
        return NULL;
    }

    world->loaded = false;
    world->wireframe_color = 15;

    return world;
}

void pxl8_world_destroy(pxl8_world* world) {
    if (!world) return;

    if (world->loaded) {
        pxl8_bsp_destroy(&world->bsp);
    }

    free(world);
}

pxl8_result pxl8_world_generate(pxl8_world* world, pxl8_gfx* gfx, const pxl8_procgen_params* params) {
    if (!world || !gfx || !params) return PXL8_ERROR_INVALID_ARGUMENT;

    if (world->loaded) {
        pxl8_bsp_destroy(&world->bsp);
        world->loaded = false;
    }

    memset(&world->bsp, 0, sizeof(pxl8_bsp));

    pxl8_result result = pxl8_procgen(&world->bsp, params);
    if (result != PXL8_OK) {
        pxl8_error("Failed to generate world");
        pxl8_bsp_destroy(&world->bsp);
        return result;
    }

    world->loaded = true;
    return PXL8_OK;
}

pxl8_result pxl8_world_apply_textures(pxl8_world* world, const pxl8_world_texture* textures, u32 count) {
    if (!world || !world->loaded || !textures || count == 0) {
        return PXL8_ERROR_INVALID_ARGUMENT;
    }

    pxl8_bsp* bsp = &world->bsp;

    u32 max_texinfo = count * 6;
    bsp->texinfo = calloc(max_texinfo, sizeof(pxl8_bsp_texinfo));
    if (!bsp->texinfo) {
        return PXL8_ERROR_OUT_OF_MEMORY;
    }
    bsp->num_texinfo = 0;

    for (u32 face_idx = 0; face_idx < bsp->num_faces; face_idx++) {
        pxl8_bsp_face* face = &bsp->faces[face_idx];
        pxl8_vec3 normal = bsp->planes[face->plane_id].normal;

        u32 matched_texture_idx = count;
        for (u32 tex_idx = 0; tex_idx < count; tex_idx++) {
            if (textures[tex_idx].rule && textures[tex_idx].rule(&normal, face, bsp)) {
                matched_texture_idx = tex_idx;
                break;
            }
        }

        if (matched_texture_idx >= count) {
            pxl8_warn("No texture rule matched for face %u", face_idx);
            continue;
        }

        const pxl8_world_texture* matched = &textures[matched_texture_idx];

        pxl8_vec3 u_axis, v_axis;
        if (fabsf(normal.y) > 0.9f) {
            u_axis = (pxl8_vec3){1.0f, 0.0f, 0.0f};
            v_axis = (pxl8_vec3){0.0f, 0.0f, 1.0f};
        } else if (fabsf(normal.x) > 0.7f) {
            u_axis = (pxl8_vec3){0.0f, 1.0f, 0.0f};
            v_axis = (pxl8_vec3){0.0f, 0.0f, 1.0f};
        } else {
            u_axis = (pxl8_vec3){1.0f, 0.0f, 0.0f};
            v_axis = (pxl8_vec3){0.0f, 1.0f, 0.0f};
        }

        u32 texinfo_idx = bsp->num_texinfo;
        bool found_existing = false;
        for (u32 i = 0; i < bsp->num_texinfo; i++) {
            if (strcmp(bsp->texinfo[i].name, matched->name) == 0 &&
                bsp->texinfo[i].miptex == matched->texture_id &&
                bsp->texinfo[i].u_axis.x == u_axis.x &&
                bsp->texinfo[i].u_axis.y == u_axis.y &&
                bsp->texinfo[i].u_axis.z == u_axis.z &&
                bsp->texinfo[i].v_axis.x == v_axis.x &&
                bsp->texinfo[i].v_axis.y == v_axis.y &&
                bsp->texinfo[i].v_axis.z == v_axis.z) {
                texinfo_idx = i;
                found_existing = true;
                break;
            }
        }

        if (!found_existing) {
            if (bsp->num_texinfo >= max_texinfo) {
                pxl8_error("Too many unique texinfo entries");
                return PXL8_ERROR_OUT_OF_MEMORY;
            }

            memcpy(bsp->texinfo[texinfo_idx].name, matched->name, sizeof(bsp->texinfo[texinfo_idx].name));
            bsp->texinfo[texinfo_idx].name[sizeof(bsp->texinfo[texinfo_idx].name) - 1] = '\0';
            bsp->texinfo[texinfo_idx].miptex = matched->texture_id;
            bsp->texinfo[texinfo_idx].u_offset = 0.0f;
            bsp->texinfo[texinfo_idx].v_offset = 0.0f;
            bsp->texinfo[texinfo_idx].u_axis = u_axis;
            bsp->texinfo[texinfo_idx].v_axis = v_axis;

            bsp->num_texinfo++;
        }

        face->texinfo_id = texinfo_idx;
    }

    pxl8_info("Applied %u textures to %u faces, created %u texinfo entries",
              count, bsp->num_faces, bsp->num_texinfo);

    return PXL8_OK;
}

pxl8_result pxl8_world_load(pxl8_world* world, const char* path) {
    if (!world || !path) return PXL8_ERROR_INVALID_ARGUMENT;

    if (world->loaded) {
        pxl8_bsp_destroy(&world->bsp);
        world->loaded = false;
    }

    memset(&world->bsp, 0, sizeof(pxl8_bsp));

    pxl8_result result = pxl8_bsp_load(path, &world->bsp);
    if (result != PXL8_OK) {
        pxl8_error("Failed to load world: %s", path);
        return result;
    }

    world->loaded = true;
    pxl8_info("Loaded world: %s", path);

    return PXL8_OK;
}

void pxl8_world_render(pxl8_world* world, pxl8_gfx* gfx, pxl8_vec3 camera_pos) {
    if (!world || !gfx || !world->loaded) return;

    if (world->wireframe) {
        pxl8_bsp_render_wireframe(gfx, &world->bsp, camera_pos, world->wireframe_color);
    } else {
        pxl8_bsp_render_textured(gfx, &world->bsp, camera_pos);
    }
}

void pxl8_world_unload(pxl8_world* world) {
    if (!world || !world->loaded) return;

    pxl8_bsp_destroy(&world->bsp);
    world->loaded = false;
}

bool pxl8_world_is_loaded(const pxl8_world* world) {
    return world && world->loaded;
}