#include <device/def_device_op.h>
#include <device/device.h>
#include <device/pci.h>
#include <device/pci_info.h>
#include <device/pci_xhci.h>
#include <device/xhci.h>
#include <libk/align.h>
#include <libk/lengthof.h>
#include <libk/printf.h>
#include <libk/std.h>
#include <limine/requests.h>
#include <proc/proc.h>
#include <proc/reschedule.h>
#include <sys/debug.h>
#include <sys/mm.h>

static int xhci_counter = 0;

bool pci_xhci_init (struct proc* proc, struct reschedule_ctx* rctx, struct pci_info pci_info) {
  struct limine_hhdm_response* hhdm = limine_hhdm_request.response;

  uint8_t progif = pci_read8 (pci_info.bus, pci_info.slot, pci_info.func, PCI_PROG_IF);

  /* not an XHCI controller */
  if (progif != 0x30) {
    return true;
  }

  uint16_t pci_cmd = pci_read16 (pci_info.bus, pci_info.slot, pci_info.func, PCI_COMMAND);

  uint16_t new_cmd = (pci_cmd | (1 << 1) | (1 << 2));

  if (pci_cmd != new_cmd) {
    pci_write16 (pci_info.bus, pci_info.slot, pci_info.func, PCI_COMMAND, new_cmd);
  }

  uintptr_t xhci_phys = 0;

  uint32_t bar0 = pci_read32 (pci_info.bus, pci_info.slot, pci_info.func, PCI_BAR0);

  if ((bar0 & PCI_BAR_MEM64)) {
    uint32_t bar1 = pci_read32 (pci_info.bus, pci_info.slot, pci_info.func, PCI_BAR1);
    xhci_phys = ((uint64_t)bar1 << 32) | (bar0 & ~0xF);
    DEBUG ("XHCI phys base addr=%p (64 bit)\n", xhci_phys);
  } else {
    xhci_phys = (bar0 & ~0xF);
    DEBUG ("XHCI phys base addr=%p (32 bit)\n", xhci_phys);
  }

  if (xhci_phys == 0) {
    DEBUG ("WARNING xhci_phys is NULL!\n");
    return false;
  }

  uintptr_t xhci_base = xhci_phys + (uintptr_t)hhdm->offset;

  /* 2 pages should cover the mmio space */
  mm_map_kernel_page (xhci_phys, xhci_base, MM_PG_RW | MM_PG_PRESENT);
  mm_map_kernel_page (xhci_phys + PAGE_SIZE, xhci_base + PAGE_SIZE, MM_PG_RW | MM_PG_PRESENT);

  char key[32];
  snprintf (key, sizeof (key), "xhci%d", xhci_counter++);

  struct xhci_init init = {.xhci_mmio_base = xhci_base};

  device_op_func_t ops[] = {0};

  struct device* xhci =
      device_create (key, ops, lengthof (ops), &xhci_init, &xhci_fini, &init, proc, rctx);

  return true;
}