#include "type.h"
#include "stdio.h"
#include "const.h"
#include "protect.h"
#include "string.h"
#include "proc.h"
#include "tty.h"
#include "console.h"
#include "global.h"
#include "keyboard.h"
#include "proto.h"
#include "x86.h"
#include "memman.h"
#include "assert.h"
#include "csi.h"
/*****************************************************************************
 * Low level vga driver
 *****************************************************************************/

/*****************************************************************************
 * Display the cursor by setting CRTC (6845 compatible) registers.
 *
 * @param position  Position of the cursor based on the beginning of the video
 *                  memory. Note that it counts in WORDs, not in BYTEs.
 *****************************************************************************/
static inline void vga_set_cursor(unsigned int position)
{
	disable_int();
	outb(CRTC_ADDR_REG, CURSOR_H);
	outb(CRTC_DATA_REG, (position >> 8) & 0xFF);
	outb(CRTC_ADDR_REG, CURSOR_L);
	outb(CRTC_DATA_REG, position & 0xFF);
	enable_int();
}

static inline void vga_disable_cursor()
{
	outb(CRTC_ADDR_REG, 0x0A);
	outb(CRTC_DATA_REG, 0x20);
}

static inline void vga_enable_cursor(u8 cursor_start, u8 cursor_end)
{
	outb(0x3D4, 0x0A);
	outb(0x3D5, (inb(0x3D5) & 0xC0) | cursor_start);

	outb(0x3D4, 0x0B);
	outb(0x3D5, (inb(0x3D5) & 0xE0) | cursor_end);
}

/*****************************************************************************
 * Routine for hardware screen scrolling.
 *
 * @param addr  Offset in the video memory.
 *****************************************************************************/
static inline void vga_set_video_start_addr(u32 addr)
{
	disable_int();
	outb(CRTC_ADDR_REG, START_ADDR_H);
	outb(CRTC_DATA_REG, (addr >> 8) & 0xFF);
	outb(CRTC_ADDR_REG, START_ADDR_L);
	outb(CRTC_DATA_REG, addr & 0xFF);
	enable_int();
}

/*****************************************************************************
 * Write data directly to Video Memory cell
 *
 * @param pos  text mode position(pos*2 yourself)
 * @param dat  data to be written, with format [ BG | FG |  ASCII  ]
 *****************************************************************************/
static inline void vga_put_raw(u32 pos, u16 dat)
{
	u16 *pch = (u16 *)K_PHY2LIN(V_MEM_BASE + pos);
	*pch = dat;
}

/*****************************************************************************
 * copy a whole screen of text mode data into video memory, assume that screen
 * width is 80 or 40
 *
 * @param src  memory block with the same size as text mode video memory()
 *****************************************************************************/
static inline void vga_flush_screen(void *src)
{
	u32 *_src = src;
	u32 *dst = (u32 *)K_PHY2LIN(V_MEM_BASE);
	for (int i = 0; i < SCR_SIZE * sizeof(u16) / sizeof(u32); ++i)
	{
		*dst++ = *_src++;
	}
}

/*****************************************************************************
 * copy a whole screen of text mode data into video memory, assume that screen
 * width is 80 or 40
 *
 * @param src  memory block with the same size as text mode video memory()
 *****************************************************************************/
static inline void vga_flush_line(void *src, int line_no)
{
	u32 *_src = src;
	u32 *dst = (u32 *)K_PHY2LIN(V_MEM_BASE + line_no * SCR_WIDTH * 2);
	for (int i = 0; i < SCR_WIDTH * sizeof(u16) / sizeof(u32); ++i)
	{
		*dst++ = *_src++;
	}
}

static inline void vga_flush_blankline(int line_no)
{
	u32 *dst = (u32 *)K_PHY2LIN(V_MEM_BASE + line_no * SCR_WIDTH * 2);
	for (int i = 0; i < SCR_WIDTH * sizeof(u16) / sizeof(u32); ++i)
	{
		*dst++ = (BLANK << 16) | BLANK;
	}
}

/*****************************************************************************
 * tty - vga driver
 *****************************************************************************/

void vga_tty_init(NTTY *tty)
{
	static int _cnt = 0;
	assert(tty->driver_type == 1);
	assert(tty->output_buf);
	vga_buf *vga = tty->output_buf;
	vga->buf = (void *)K_PHY2LIN(do_kmalloc(sizeof(u16) * SCR_BUFSIZE));
	// vga->buf = (void *)pagebuf[_cnt++];
	// kprintf("malloced %p %p %p\n", vga->buf, &vga->buf, &vga->scr_top_line);
	vga->cur_col = vga->cur_row = 0;
	// buf->max_line = SCR_BUFSIZE / SCR_WIDTH;
	vga->scr_top_line = vga->scr_cur_line = vga->scr_bot_line = 0;
	vga->head_line = 0;
	vga->IsColorReverse = false;
	vga->IsHide = false;
	vga->color = DEFAULT_CHAR_COLOR;
	vga->CSI = CSI_ESC;
	u32 *ptr_buf = (u32 *)vga->buf;
	for (int i = 0; i < SCR_BUFSIZE * sizeof(u16) / sizeof(u32); ++i)
	{
		ptr_buf[i] = (BLANK << 16) | BLANK; // bg-black, fg-white, ascii-space
	}
	// kprintf("%p 0x%x %d\n", vga->buf, ((u32 *)vga->buf)[20], vga->scr_cur_line);
}

#define INDEX(row, col) ((row)*SCR_WIDTH + (col))
#define NEXTLINE(row) NEXT(row, SCR_MAXLINE)
#define LASTLINE(row) LAST(row, SCR_MAXLINE)
#define ADDLINE(row, add_num) (((row) + add_num) % SCR_MAXLINE)

static void newline(vga_buf *vga)
{
	u16 *buf = vga->buf;
	vga->cur_col = 0;
	vga->scr_cur_line = NEXTLINE(vga->scr_cur_line);
	vga->cur_row = CYCLE_SUB(vga->scr_top_line, vga->scr_cur_line, SCR_MAXLINE);
	if (vga->cur_row == SCR_HEIGHT)
	{
		// auto scroll
		vga->scr_top_line = NEXTLINE(vga->scr_top_line);
	}
	if (vga->scr_cur_line == vga->head_line)
	{
		vga->head_line = NEXTLINE(vga->head_line);
		// remember to fill blank the old line
		u32 *ptr_buf = (u32 *)(vga->buf + sizeof(u16) * vga->scr_cur_line * SCR_WIDTH);
		for (int i = 0; i < SCR_WIDTH * sizeof(u16) / sizeof(u32); ++i)
		{
			*ptr_buf++ = (BLANK << 16) | BLANK; // bg-black, fg-white, ascii-space
		}
	}
}

static void nextcol(vga_buf *vgabuf)
{
	vgabuf->cur_col++;
	if (vgabuf->cur_col == SCR_WIDTH)
	{
		newline(vgabuf);
	}
}

void vga_tty_write(NTTY *tty, char ch)
{
	// assert(tty->driver_type == 1);
	// assert(tty->output_buf);
	vga_buf *vga = tty->output_buf;
	u16 *buf = vga->buf;
	// kprintf("vga_tty_write %c to %d %d\n", ch, vga->scr_cur_line, vga->cur_col);
	if (vga->CSI == CSI_ESC)
	{
		switch (ch)
		{
		case '\t':
			if (INDEX(vga->scr_cur_line, vga->cur_col) == SCR_BUFSIZE - 1)
				break;
			while (vga->cur_col % 4 != 1)
			{
				nextcol(vga);
			}
			break;
		case '\n':
			newline(vga);
			break;
		case '\r':
			vga->cur_col = 0;
			break;
		case '\b':
			// this implementation is mimic to usual linux shell
			// it moves cursor left but neither crosses line nor delete character
			if (vga->cur_col > 0)
			{
				vga->cur_col--;
			}
			break;
		case '\x1b':
			vga->CSI = CSI_BRACKET;
			break;
		default:
			buf[INDEX(vga->scr_cur_line, vga->cur_col)] = MAKE_CELL(vga->color, ch);
			// buf[INDEX(vga->scr_cur_line, vga->cur_col)] = MAKE_CELL(DEFAULT_CHAR_COLOR, ch);
			nextcol(vga);
			break;
		}
	}
	else if (vga->CSI == CSI_BRACKET)
	{
		switch (ch)
		{
		case '[':
			vga->CSI = CSI_PARAM;
			// init
			for (int i = 0; i < MAXNUM_PARAM_CH; i++)
			{
				vga->param_c[i] = 0;
			}
			vga->param_num = 0;
			break;
		default:
			vga->CSI = CSI_ESC;
			break;
		}
	}
	else
	{
		switch (ch)
		{
		case '0':
		case '1':
		case '2':
		case '3':
		case '4':
		case '5':
		case '6':
		case '7':
		case '8':
		case '9':
		case ';':
			if (vga->param_num < MAXNUM_PARAM_CH)
			{
				vga->param_c[vga->param_num] = ch;
				vga->param_num++;
			}
			break;
		default:
			if (!(0x20 <= ch && ch <= 0x7e))
				vga->CSI = CSI_ESC;
			if (0x40 <= ch && ch <= 0x7e)
				CSI_handler(ch, vga);
			break;
		}
	}
	vga->cur_row = CYCLE_SUB(vga->scr_top_line, vga->scr_cur_line, SCR_MAXLINE);
	if (CYCLE_SUB(vga->head_line, vga->scr_cur_line, SCR_MAXLINE) >= CYCLE_SUB(vga->head_line, vga->scr_bot_line, SCR_MAXLINE))
	{
		vga->scr_bot_line = vga->scr_cur_line;
	}
	// kprintf("row: %d; ", vga->cur_row);
}

void vga_tty_flush(NTTY *tty)
{
	vga_buf *vga = tty->output_buf;
	u16 *buf = vga->buf;
	int i, cur_line;
	vga_set_cursor(INDEX(vga->cur_row, vga->cur_col));
	vga->cur_row = CYCLE_SUB(vga->scr_top_line, vga->scr_cur_line, SCR_MAXLINE);
	int bottom = min(max(vga->cur_row, CYCLE_SUB(vga->scr_top_line, vga->scr_bot_line, SCR_MAXLINE)), SCR_HEIGHT);
	// if (vga->cur_row == SCR_HEIGHT - 1)
	// {
	// 	vga_flush_screen(&buf[INDEX(vga->scr_top_line, 0)]);

	// }
	// else
	// {
	cur_line = vga->scr_top_line;
	for (i = 0; i <= bottom; ++i)
	{
		vga_flush_line(&buf[INDEX(cur_line, 0)], i);
		cur_line = NEXTLINE(cur_line);
	}
	for (; i < SCR_HEIGHT; ++i)
	{
		vga_flush_blankline(i);
	}
	// }
	// kprintf("flush: row=%d, top=%d, cur=%d\n", vga->cur_row, vga->scr_top_line, vga->scr_cur_line);
}

void vga_tty_scroll(NTTY *tty, int direction)
{
	vga_buf *vga = tty->output_buf;
	u16 *buf = vga->buf;
	if (direction == MOUSESCR_DOWN)
	{
		// down
		if (vga->scr_top_line == vga->scr_cur_line)
			return;
		vga->scr_top_line = NEXTLINE(vga->scr_top_line);
	}
	else if (direction == MOUSESCR_UP)
	{
		if (vga->scr_top_line == vga->head_line)
			return;
		vga->scr_top_line = LASTLINE(vga->scr_top_line);
	}
	else
	{
		if (CYCLE_SUB(vga->scr_top_line, vga->scr_cur_line, SCR_MAXLINE) >= SCR_HEIGHT)
		{

			vga->scr_top_line = CYCLE_SUB(SCR_HEIGHT / 2, vga->scr_cur_line, SCR_MAXLINE);
		}
		// kprintf("scroll to cur top-%d, cur-%d\n", vga->scr_top_line, vga->scr_cur_line);
	}
	vga->cur_row = CYCLE_SUB(vga->scr_top_line, vga->scr_cur_line, SCR_MAXLINE);
	if (vga->cur_row >= SCR_HEIGHT)
	{
		vga_disable_cursor();
		// kprintf("disable cursor: %d\n", vga->cur_row);
	}
	else
	{
		vga_enable_cursor(14, 15);
	}
	vga_tty_flush(tty);
}

void vga_tty_select(NTTY *tty)
{
	disable_int();
	cur_ntty = tty;
	enable_int();
	vga_tty_flush(cur_ntty);
}