#include <stdint.h>
#include <stdlib.h>
#include <curses.h>

#include "chat.h"

int utf8_char_int (const char *string);
const char *utf8_next_char (const char *string);
void gui_nick_hash_djb2_64 (const char *nickname, uint64_t *color_64);
int gui_nick_hash_color (const char *nickname);
enum Color bx_weechat_nick_colors(const char *nick);

int
utf8_char_int (const char *string)
{
    const unsigned char *ptr_string;

    if (!string)
        return 0;

    ptr_string = (unsigned char *)string;

    /* UTF-8, 2 bytes: 110vvvvv 10vvvvvv */
    if ((ptr_string[0] & 0xE0) == 0xC0)
    {
        if (!ptr_string[1])
            return (int)(ptr_string[0] & 0x1F);
        return ((int)(ptr_string[0] & 0x1F) << 6) +
            ((int)(ptr_string[1] & 0x3F));
    }
    /* UTF-8, 3 bytes: 1110vvvv 10vvvvvv 10vvvvvv */
    else if ((ptr_string[0] & 0xF0) == 0xE0)
    {
        if (!ptr_string[1])
            return (int)(ptr_string[0] & 0x0F);
        if (!ptr_string[2])
            return (((int)(ptr_string[0] & 0x0F)) << 6) +
                ((int)(ptr_string[1] & 0x3F));
        return (((int)(ptr_string[0] & 0x0F)) << 12) +
            (((int)(ptr_string[1] & 0x3F)) << 6) +
            ((int)(ptr_string[2] & 0x3F));
    }
    /* UTF-8, 4 bytes: 11110vvv 10vvvvvv 10vvvvvv 10vvvvvv */
    else if ((ptr_string[0] & 0xF8) == 0xF0)
    {
        if (!ptr_string[1])
            return (int)(ptr_string[0] & 0x07);
        if (!ptr_string[2])
            return (((int)(ptr_string[0] & 0x07)) << 6) +
                ((int)(ptr_string[1] & 0x3F));
        if (!ptr_string[3])
            return (((int)(ptr_string[0] & 0x07)) << 12) +
                (((int)(ptr_string[1] & 0x3F)) << 6) +
                ((int)(ptr_string[2] & 0x3F));
        return (((int)(ptr_string[0] & 0x07)) << 18) +
            (((int)(ptr_string[1] & 0x3F)) << 12) +
            (((int)(ptr_string[2] & 0x3F)) << 6) +
            ((int)(ptr_string[3] & 0x3F));
    }
    /* UTF-8, 1 byte: 0vvvvvvv */
    return (int)ptr_string[0];
}

const char *
utf8_next_char (const char *string)
{
    if (!string)
        return NULL;

    /* UTF-8, 2 bytes: 110vvvvv 10vvvvvv */
    if (((unsigned char)(string[0]) & 0xE0) == 0xC0)
    {
        if (!string[1])
            return (char *)string + 1;
        return (char *)string + 2;
    }
    /* UTF-8, 3 bytes: 1110vvvv 10vvvvvv 10vvvvvv */
    else if (((unsigned char)(string[0]) & 0xF0) == 0xE0)
    {
        if (!string[1])
            return (char *)string + 1;
        if (!string[2])
            return (char *)string + 2;
        return (char *)string + 3;
    }
    /* UTF-8, 4 bytes: 11110vvv 10vvvvvv 10vvvvvv 10vvvvvv */
    else if (((unsigned char)(string[0]) & 0xF8) == 0xF0)
    {
        if (!string[1])
            return (char *)string + 1;
        if (!string[2])
            return (char *)string + 2;
        if (!string[3])
            return (char *)string + 3;
        return (char *)string + 4;
    }
    /* UTF-8, 1 byte: 0vvvvvvv */
    return (char *)string + 1;
}

void
gui_nick_hash_djb2_64 (const char *nickname, uint64_t *color_64)
{
    while (nickname && nickname[0])
    {
        *color_64 ^= (*color_64 << 5) + (*color_64 >> 2) +
            utf8_char_int (nickname);
        nickname = utf8_next_char (nickname);
    }
}

/* cyan, magenta, green, brown, lightblue,
default, lightcyan, lightmagenta, lightgreen, blue */

/*
 * Hashes a nickname to find color.
 *
 * Returns a number which is the index of color in the nicks colors of option
 * "weechat.color.chat_nick_colors".
 */

int
gui_nick_hash_color (const char *nickname)
{
    const char *ptr_salt;
    uint64_t color_64;

    ptr_salt = "";

    color_64 = 0;

    switch (1)
    {
        default:
            /* variant of djb2 hash */
            color_64 = 5381;
            gui_nick_hash_djb2_64 (ptr_salt, &color_64);
            gui_nick_hash_djb2_64 (nickname, &color_64);
            break;
    }

    return (color_64 % 10);
}

/*
	cyan, magenta, green, brown, lightblue,
	default, lightcyan, lightmagenta, lightgreen, blue
*/

/*
struct t_gui_color gui_weechat_colors_bold[GUI_CURSES_NUM_WEECHAT_COLORS + 1] =
{ { -1,                -1,                0,      "default"      },
{ COLOR_BLACK,       COLOR_BLACK,       0,      "black"        },
{ COLOR_BLACK,       COLOR_BLACK + 8,   A_BOLD, "darkgray"     },
{ COLOR_RED,         COLOR_RED,         0,      "red"          },
{ COLOR_RED,         COLOR_RED + 8,     A_BOLD, "lightred"     },
{ COLOR_GREEN,       COLOR_GREEN,       0,      "green"        },
{ COLOR_GREEN,       COLOR_GREEN + 8,   A_BOLD, "lightgreen"   },
{ COLOR_YELLOW,      COLOR_YELLOW,      0,      "brown"        },
{ COLOR_YELLOW,      COLOR_YELLOW + 8,  A_BOLD, "yellow"       },
{ COLOR_BLUE,        COLOR_BLUE,        0,      "blue"         },
{ COLOR_BLUE,        COLOR_BLUE + 8,    A_BOLD, "lightblue"    },
{ COLOR_MAGENTA,     COLOR_MAGENTA,     0,      "magenta"      },
{ COLOR_MAGENTA,     COLOR_MAGENTA + 8, A_BOLD, "lightmagenta" },
{ COLOR_CYAN,        COLOR_CYAN,        0,      "cyan"         },
{ COLOR_CYAN,        COLOR_CYAN + 8,    A_BOLD, "lightcyan"    },
{ COLOR_WHITE,       COLOR_WHITE,       0,      "gray"         },
{ COLOR_WHITE,       COLOR_WHITE + 8,   A_BOLD, "white"        },
{ 0,                 0,                 0,      NULL           }
};
*/

/*
	[Default]    = -1,
	[White]      = 8 + COLOR_WHITE,
	[Black]      = 0 + COLOR_BLACK,
	[Blue]       = 0 + COLOR_BLUE,
	[Green]      = 0 + COLOR_GREEN,
	[Red]        = 8 + COLOR_RED,
	[Brown]      = 0 + COLOR_RED,
	[Magenta]    = 0 + COLOR_MAGENTA,
	[Orange]     = 0 + COLOR_YELLOW,
	[Yellow]     = 8 + COLOR_YELLOW,
	[LightGreen] = 8 + COLOR_GREEN,
	[Cyan]       = 0 + COLOR_CYAN,
	[LightCyan]  = 8 + COLOR_CYAN,
	[LightBlue]  = 8 + COLOR_BLUE,
	[Pink]       = 8 + COLOR_MAGENTA,
	[Gray]       = 8 + COLOR_BLACK,
	[LightGray]  = 0 + COLOR_WHITE,
*/

// enum Color bx_weechat_nick_colors(const char *nick) {
uint32_t weechat_nick_colors(const char *nick) {
	enum Color weechat_colors[] = {
		Cyan, Magenta, Green, Orange, LightBlue,
		Default, LightCyan, Pink, LightGreen, Blue,
	};

	int color = gui_nick_hash_color(nick);

	return (uint32_t) weechat_colors[color];
}