#include <klibc/string.h>
#include <lunaix/spike.h>
#include <lunaix/tty/tty.h>
#include <stdint.h>
#include <lunaix/owloysius.h>
#include <lunaix/mm/pagetable.h>
#include <lunaix/mm/mmio.h>

#include <asm/x86_pmio.h>

vga_attribute* tty_vga_buffer;

vga_attribute tty_theme_color = VGA_COLOR_BLACK;

inline void
tty_clear()
{
    asm volatile("rep stosw" ::"D"(tty_vga_buffer),
                 "c"(TTY_HEIGHT * TTY_WIDTH),
                 "a"(tty_theme_color)
                 : "memory");
}

void
tty_init(void* vga_buf)
{
    tty_vga_buffer = (vga_attribute*)vga_buf;

    tty_clear();

    port_wrbyte(0x3D4, 0x0A);
    port_wrbyte(0x3D5, (port_rdbyte(0x3D5) & 0xC0) | 13);

    port_wrbyte(0x3D4, 0x0B);
    port_wrbyte(0x3D5, (port_rdbyte(0x3D5) & 0xE0) | 15);
}

void
tty_set_cursor(u8_t x, u8_t y)
{
    if (x >= TTY_WIDTH || y >= TTY_HEIGHT) {
        x = y = 0;
    }
    u32_t pos = y * TTY_WIDTH + x;
    port_wrbyte(0x3D4, 14);
    port_wrbyte(0x3D5, pos / 256);
    port_wrbyte(0x3D4, 15);
    port_wrbyte(0x3D5, pos % 256);
}

void
tty_set_theme(vga_attribute fg, vga_attribute bg)
{
    tty_theme_color = (bg << 4 | fg) << 8;
}

void
tty_flush_buffer(struct fifo_buf* buf)
{
    int x = 0, y = 0;

    // Clear screen
    tty_clear();

    char chr;
    while (fifo_readone_async(buf, (u8_t*)&chr)) {
        switch (chr) {
            case '\t':
                x += 4;
                break;
            case '\n':
                y++;
                // fall through
            case '\r':
                x = 0;
                break;
            default:
                *(tty_vga_buffer + x + y * TTY_WIDTH) =
                    (tty_theme_color | chr);
                (x)++;
                break;
        }

        if (x >= TTY_WIDTH) {
            x = 0;
            y++;
        }
        if (y >= TTY_HEIGHT) {
            y--;
            break;
        }
    }

    tty_set_cursor(x, y);
}

void
tty_clear_line(int line_num)
{
    asm volatile("rep stosw" ::"D"(tty_vga_buffer + line_num * TTY_WIDTH),
                 "c"(TTY_WIDTH),
                 "a"(tty_theme_color)
                 : "memory");
}

void
tty_put_str_at(char* str, int x, int y)
{
    char c;
    while ((c = (*str)) && y < TTY_HEIGHT) {
        *(tty_vga_buffer + x + y * TTY_WIDTH) = c | tty_theme_color;
        x++;
        if (x >= TTY_WIDTH) {
            y++;
            x = 0;
        }
        str++;
    }
}

static void
vga_rawtty_init()
{
    // FIXME we should get rid of it at some point
    tty_init((void*)ioremap(0xB8000, PAGE_SIZE));
    tty_set_theme(VGA_COLOR_WHITE, VGA_COLOR_BLACK);
}
owloysius_fetch_init(vga_rawtty_init, on_earlyboot);