#include "multiboot2.h"
#include "fb.h"
#include "mem.h"
#include <stdint.h>
#include "klog.h"
#include "mm.h"

static uint32_t mbinfo[2048];

static void mbinfo_process_tag(const multiboot2_info_tag_t * tag)
{
    switch (tag->type)
    {
    case MULTIBOOT2_INFO_BOOT_COMMAND_LINE:
        {
            multiboot2_info_boot_command_line_t * cl =
                (multiboot2_info_boot_command_line_t *)tag;
            klog_printf("Kernel boot command line: '%s'\n", cl->string);
        }
        break;

    case MULTIBOOT2_INFO_BOOT_LOADER_NAME:
        {
            multiboot2_info_boot_loader_name_t * bln =
                (multiboot2_info_boot_loader_name_t *)tag;
            klog_printf("Boot loader: '%s'\n", bln->string);
        }
        break;

    case MULTIBOOT2_INFO_MEMORY_MAP:
        {
            multiboot2_info_memory_map_t * mmap_info =
                (multiboot2_info_memory_map_t *)tag;
            size_t sz = sizeof(mmap_info->header) +
                sizeof(mmap_info->entry_size) +
                sizeof(mmap_info->entry_version);
            multiboot2_info_memory_map_entry_t * entry = &mmap_info->entries[0];
            for (;;)
            {
                sz += mmap_info->entry_size;
                if (sz > mmap_info->header.size)
                {
                    break;
                }
                if (entry->type == MULTIBOOT2_MEMORY_MAP_TYPE_RAM)
                {
                    klog_printf("Memory region %16lx : %16lx\n",
                            entry->base_addr,
                            entry->length);
                    mm_register_ram_region(entry->base_addr, entry->length);
                }
                entry = (multiboot2_info_memory_map_entry_t *)((uintptr_t)entry + mmap_info->entry_size);
            }
        }
        break;

    case MULTIBOOT2_INFO_FRAMEBUFFER_INFO:
        {
            multiboot2_info_framebuffer_info_t * fbinfo =
                (multiboot2_info_framebuffer_info_t *)tag;
            fb_init((uint32_t *)(uintptr_t)fbinfo->framebuffer_addr,
                    fbinfo->framebuffer_width,
                    fbinfo->framebuffer_height,
                    fbinfo->framebuffer_pitch);
        }
        break;
    }
}

static void process_tags(const multiboot2_info_tag_t * tag, bool init)
{
    while (tag->type != 0u)
    {
        if ((init && (tag->type == MULTIBOOT2_INFO_FRAMEBUFFER_INFO)) ||
                (!init && (tag->type != MULTIBOOT2_INFO_FRAMEBUFFER_INFO)))
        {
            mbinfo_process_tag(tag);
        }
        tag = multiboot2_info_next_tag(tag);
    }
}

bool mbinfo_init(uint32_t mbinfo_addr)
{
    multiboot2_info_header_t * mbinfo_header = (multiboot2_info_header_t *)mbinfo_addr;
    if (mbinfo_header->total_size <= sizeof(mbinfo))
    {
        memcpy32(mbinfo, mbinfo_header, mbinfo_header->total_size / 4u);
        multiboot2_info_tag_t * tag = (multiboot2_info_tag_t *)(mbinfo + sizeof(multiboot2_info_header_t) / 4u);
        process_tags(tag, true);
        return true;
    }
    return false;
}

void mbinfo_load(void)
{
    multiboot2_info_tag_t * tag = (multiboot2_info_tag_t *)(mbinfo + sizeof(multiboot2_info_header_t) / 4u);
    process_tags(tag, false);
}