#include "cairo_bindings.h"
#include "texture.h"

int honey_cairo_mt_ref = LUA_NOREF;

static const cairo_user_data_key_t TEXTURE_KEY;

int honey_setup_cairo(lua_State* L)
{
    honey_lua_create_table
        (L, 2,
         HONEY_TABLE, "__index", 18,
         HONEY_FUNCTION, "getTexture", honey_cairo_get_texture,
         HONEY_FUNCTION, "updateTexture", honey_cairo_update_texture,

	 /* config functions */
	 HONEY_FUNCTION, "save", honey_cairo_save,
	 HONEY_FUNCTION, "restore", honey_cairo_restore,
	 HONEY_FUNCTION, "setOperator", honey_cairo_set_operator,
	 HONEY_FUNCTION, "getOperator", honey_cairo_get_operator,
	 HONEY_FUNCTION, "setAntialias", honey_cairo_set_antialias,
	 HONEY_FUNCTION, "getAntialias", honey_cairo_get_antialias,
	 HONEY_FUNCTION, "setColor", honey_cairo_set_color,
	 HONEY_FUNCTION, "setLinecap", honey_cairo_set_linecap,
	 HONEY_FUNCTION, "getLinecap", honey_cairo_get_linecap,
	 HONEY_FUNCTION, "setLineWidth", honey_cairo_set_line_width,

	 /* drawing functions */
         HONEY_FUNCTION, "moveTo", honey_cairo_move_to,
         HONEY_FUNCTION, "lineTo", honey_cairo_line_to,
	 HONEY_FUNCTION, "curveTo", honey_cairo_curve_to,
	 HONEY_FUNCTION, "arc", honey_cairo_arc,
         HONEY_FUNCTION, "stroke", honey_cairo_stroke,
	 HONEY_FUNCTION, "fill", honey_cairo_fill,

         HONEY_FUNCTION, "__gc", honey_cairo_destroy);
    honey_cairo_mt_ref = luaL_ref(L, LUA_REGISTRYINDEX);

    lua_pushcfunction(L, honey_cairo_new);
    lua_setfield(L, -2, "cairo");
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

struct texture_ref {
    int ref;
    lua_State* L;
};

static void destroy_texture_ref(void* data)
{
    struct texture_ref* ref = data;
    luaL_unref(ref->L, LUA_REGISTRYINDEX, ref->ref);
    free(ref);
}

int honey_cairo_new(lua_State* L)
{
    int choice = honey_lua_parse_arguments(L, 2, 0, 1, HONEY_TABLE, NULL);

    lua_pushcfunction(L, honey_lua_texture_new);
    if (choice == 0)
        honey_lua_pcall(L, 0, 1);
    else {
        lua_pushvalue(L, 1);
        honey_lua_pcall(L, 1, 1);
    }

    /* configure texture swizzling ARGB -> RGBA */
    honey_texture* texture = lua_touserdata(L, -1);
    glBindTexture(GL_TEXTURE_2D, texture->id);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_R, GL_BLUE);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_B, GL_RED);
    //glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_SWIZZLE_A, GL_RED);

    /* setup texture reference */
    struct texture_ref* ref = malloc(sizeof(struct texture_ref));
    if (ref == NULL)
        honey_lua_throw_error
            (L, "failed to allocate memory for texture handle!");
    
    ref->ref = luaL_ref(L, LUA_REGISTRYINDEX);
    ref->L = L;

    /* create cairo surface */
    cairo_surface_t* surface =
        cairo_image_surface_create(CAIRO_FORMAT_ARGB32,
                                   texture->params.width,
                                   texture->params.height);
    
    cairo_status_t status = cairo_surface_status(surface);
    if (status != CAIRO_STATUS_SUCCESS)
        honey_lua_throw_error
            (L, "error creating cairo surface: %s", cairo_status_to_string(status));

    /* create cairo context */
    cairo_t** cr = lua_newuserdata(L, sizeof(cairo_t*));
    *cr = cairo_create(surface);
    status = cairo_status(*cr);
    if (status != CAIRO_STATUS_SUCCESS)
        honey_lua_throw_error
            (L, "error creating cairo context: %s", cairo_status_to_string(status));

    cairo_surface_destroy(surface);

    /* bind texture ref to context userdata */
    status = cairo_set_user_data(*cr,
                                 &TEXTURE_KEY,
                                 ref,
                                 destroy_texture_ref);
    if (status != CAIRO_STATUS_SUCCESS)
        honey_lua_throw_error
            (L, "error binding cairo texture: %s", cairo_status_to_string(status));

    lua_rawgeti(L, LUA_REGISTRYINDEX, honey_cairo_mt_ref);
    lua_setmetatable(L, -2);

    return 1;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_update_texture(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    struct texture_ref *ref = cairo_get_user_data(*cr, &TEXTURE_KEY);
    lua_rawgeti(L, LUA_REGISTRYINDEX, ref->ref);
    honey_texture* texture = lua_touserdata(L, -1);
    lua_pop(L, 1);

    cairo_surface_t* surface = cairo_get_target(*cr);

    glBindTexture(GL_TEXTURE_2D, texture->id);
    unsigned char* image_data = cairo_image_surface_get_data(surface);
    glTexSubImage2D(GL_TEXTURE_2D,
                    0, 0, 0,
                    texture->params.width,
                    texture->params.height,
                    GL_RGBA,
                    GL_UNSIGNED_BYTE,
                    image_data);

    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_get_texture(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    struct texture_ref *ref = cairo_get_user_data(*cr, &TEXTURE_KEY);
    lua_rawgeti(L, LUA_REGISTRYINDEX, ref->ref);
    return 1;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_destroy(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    struct texture_ref* ref = cairo_get_user_data(*cr, &TEXTURE_KEY);

    cairo_destroy(*cr);

    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * Context config functions
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

int honey_cairo_set_operator(lua_State* L)
{
    cairo_t** cr;
    char* op_string;
    honey_lua_parse_arguments(L, 1, 2, HONEY_USERDATA, &cr, HONEY_STRING, &op_string);

    cairo_operator_t op;
    
    bool ok = honey_string_to_enum
	(&op, op_string, 29,
	 "clear", CAIRO_OPERATOR_CLEAR,
	 "source", CAIRO_OPERATOR_SOURCE,
	 "over", CAIRO_OPERATOR_OVER,
	 "in", CAIRO_OPERATOR_IN,
	 "out", CAIRO_OPERATOR_OUT,
	 "atop", CAIRO_OPERATOR_ATOP,
	 "dest", CAIRO_OPERATOR_DEST,
	 "dest-over", CAIRO_OPERATOR_DEST_OVER,
	 "dest-in", CAIRO_OPERATOR_DEST_IN,
	 "dest-out", CAIRO_OPERATOR_DEST_OUT,
	 "dest-atop", CAIRO_OPERATOR_DEST_ATOP,
	 "xor", CAIRO_OPERATOR_XOR,
	 "add", CAIRO_OPERATOR_ADD,
	 "saturate", CAIRO_OPERATOR_SATURATE,
	 "multiply", CAIRO_OPERATOR_MULTIPLY,
	 "screen", CAIRO_OPERATOR_SCREEN,
	 "overlay", CAIRO_OPERATOR_OVERLAY,
	 "darken", CAIRO_OPERATOR_DARKEN,
	 "lighten", CAIRO_OPERATOR_LIGHTEN,
	 "color-dodge", CAIRO_OPERATOR_COLOR_DODGE,
	 "color-burn", CAIRO_OPERATOR_COLOR_BURN,
	 "hard-light", CAIRO_OPERATOR_HARD_LIGHT,
	 "soft-light", CAIRO_OPERATOR_SOFT_LIGHT,
	 "difference", CAIRO_OPERATOR_DIFFERENCE,
	 "exclusion", CAIRO_OPERATOR_EXCLUSION,
	 "hsl-hue", CAIRO_OPERATOR_HSL_HUE,
	 "hsl-saturation", CAIRO_OPERATOR_HSL_SATURATION,
	 "hsl-color", CAIRO_OPERATOR_HSL_COLOR,
	 "hsl-luminosity", CAIRO_OPERATOR_HSL_LUMINOSITY);

 
    if (!ok)
	honey_lua_throw_error(L, "unknown cairo operator '%s'", op_string);

    cairo_set_operator(*cr, op);
    
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_get_operator(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    cairo_operator_t op = cairo_get_operator(*cr);
    char* string;
    bool ok = honey_enum_to_string
	(&string, op, 29,
	 "clear", CAIRO_OPERATOR_CLEAR,
	 "source", CAIRO_OPERATOR_SOURCE,
	 "over", CAIRO_OPERATOR_OVER,
	 "in", CAIRO_OPERATOR_IN,
	 "out", CAIRO_OPERATOR_OUT,
	 "atop", CAIRO_OPERATOR_ATOP,
	 "dest", CAIRO_OPERATOR_DEST,
	 "dest-over", CAIRO_OPERATOR_DEST_OVER,
	 "dest-in", CAIRO_OPERATOR_DEST_IN,
	 "dest-out", CAIRO_OPERATOR_DEST_OUT,
	 "dest-atop", CAIRO_OPERATOR_DEST_ATOP,
	 "xor", CAIRO_OPERATOR_XOR,
	 "add", CAIRO_OPERATOR_ADD,
	 "saturate", CAIRO_OPERATOR_SATURATE,
	 "multiply", CAIRO_OPERATOR_MULTIPLY,
	 "screen", CAIRO_OPERATOR_SCREEN,
	 "overlay", CAIRO_OPERATOR_OVERLAY,
	 "darken", CAIRO_OPERATOR_DARKEN,
	 "lighten", CAIRO_OPERATOR_LIGHTEN,
	 "color-dodge", CAIRO_OPERATOR_COLOR_DODGE,
	 "color-burn", CAIRO_OPERATOR_COLOR_BURN,
	 "hard-light", CAIRO_OPERATOR_HARD_LIGHT,
	 "soft-light", CAIRO_OPERATOR_SOFT_LIGHT,
	 "difference", CAIRO_OPERATOR_DIFFERENCE,
	 "exclusion", CAIRO_OPERATOR_EXCLUSION,
	 "hsl-hue", CAIRO_OPERATOR_HSL_HUE,
	 "hsl-saturation", CAIRO_OPERATOR_HSL_SATURATION,
	 "hsl-color", CAIRO_OPERATOR_HSL_COLOR,
	 "hsl-luminosity", CAIRO_OPERATOR_HSL_LUMINOSITY);

    if (!ok)
	honey_lua_throw_error(L, "unknown operator '%d'", op);
    
    return 1;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_set_antialias(lua_State* L)
{
    cairo_t** cr;
    char* aa_string;
    honey_lua_parse_arguments(L, 1, 2, HONEY_USERDATA, &cr, HONEY_STRING, &aa_string);

    cairo_antialias_t aa;

    bool noerror = honey_string_to_enum
	(&aa, aa_string, 7,
	 "default", CAIRO_ANTIALIAS_DEFAULT,
	 "none", CAIRO_ANTIALIAS_NONE,
	 "gray", CAIRO_ANTIALIAS_GRAY,
	 "subpixel", CAIRO_ANTIALIAS_SUBPIXEL,
	 "fast", CAIRO_ANTIALIAS_FAST,
	 "good", CAIRO_ANTIALIAS_GOOD,
	 "best", CAIRO_ANTIALIAS_BEST);

    if (!noerror)
	honey_lua_throw_error(L, "unknown antialias type '%s'", aa_string);

    cairo_set_antialias(*cr, aa);
    
    return 0;
	
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_get_antialias(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    cairo_antialias_t aa = cairo_get_antialias(*cr);
    char* string;
    
    bool noerror = honey_enum_to_string
	(&string, aa, 7,
	 "default", CAIRO_ANTIALIAS_DEFAULT,
	 "none", CAIRO_ANTIALIAS_NONE,
	 "gray", CAIRO_ANTIALIAS_GRAY,
	 "subpixel", CAIRO_ANTIALIAS_SUBPIXEL,
	 "fast", CAIRO_ANTIALIAS_FAST,
	 "good", CAIRO_ANTIALIAS_GOOD,
	 "best", CAIRO_ANTIALIAS_BEST);

    if (!noerror)
	honey_lua_throw_error(L, "unknown antialias type '%d'", aa);

    lua_pushstring(L, string);
    
    return 1;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_save(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    cairo_save(*cr);
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_restore(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    cairo_restore(*cr);
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_set_linecap(lua_State* L)
{
    cairo_t** cr;
    char* cap_string;
    honey_lua_parse_arguments(L, 1, 2, HONEY_USERDATA, &cr, HONEY_STRING, &cap_string);

    cairo_line_cap_t cap;

    bool ok = honey_string_to_enum
	(&cap, cap_string, 3,
	 "butt", CAIRO_LINE_CAP_BUTT,
	 "round", CAIRO_LINE_CAP_ROUND,
	 "square", CAIRO_LINE_CAP_SQUARE);

    if (!ok)
	honey_lua_throw_error(L, "unknown linecap type '%s'", cap_string);

    cairo_set_line_cap(*cr, cap);
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_get_linecap(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    cairo_line_cap_t cap = cairo_get_line_cap(*cr);
    char* cap_string;

    bool ok = honey_enum_to_string
	(&cap_string, cap, 3,
	 "butt", CAIRO_LINE_CAP_BUTT,
	 "round", CAIRO_LINE_CAP_ROUND,
	 "square", CAIRO_LINE_CAP_SQUARE);

    if (!ok)
	honey_lua_throw_error(L, "unknown linecap type '%d'", cap);

    lua_pushstring(L, cap_string);
    return 1;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * Drawing functions
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */

int honey_cairo_move_to(lua_State* L)
{
    cairo_t** cr;
    float x, y;
    honey_lua_parse_arguments
        (L, 1, 3, HONEY_USERDATA, &cr, HONEY_NUMBER, &x, HONEY_NUMBER, &y);

    cairo_move_to(*cr, x, y);
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_line_to(lua_State* L)
{
    cairo_t** cr;
    float x, y;
    honey_lua_parse_arguments
        (L, 1, 3, HONEY_USERDATA, &cr, HONEY_NUMBER, &x, HONEY_NUMBER, &y);

    cairo_line_to(*cr, x, y);
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_curve_to(lua_State* L)
{
    cairo_t** cr;
    float x1, y1, x2, y2, x3, y3;
    honey_lua_parse_arguments
	(L, 1, 7, HONEY_USERDATA, &cr,
	 HONEY_NUMBER, x1, HONEY_NUMBER, y1,
	 HONEY_NUMBER, x2, HONEY_NUMBER, y2,
	 HONEY_NUMBER, x3, HONEY_NUMBER, y3);

    cairo_curve_to(*cr, x1, y1, x2, y2, x3, y3);
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_arc(lua_State* L)
{
    cairo_t** cr;
    float cx, cy, radius, angle1, angle2;
    int choice = honey_lua_parse_arguments
	(L, 2,
	 4,
	 HONEY_USERDATA, &cr,
	 HONEY_NUMBER, &cx, HONEY_NUMBER, &cy, HONEY_NUMBER, &radius,
	 6,
	 HONEY_USERDATA, &cr,
	 HONEY_NUMBER, &cx, HONEY_NUMBER, &cy, HONEY_NUMBER, &radius,
	 HONEY_NUMBER, &angle1, HONEY_NUMBER, &angle2);

    if (choice == 0) {
	angle1 = 0;
	angle2 = 6.2831;
    }

    cairo_arc(*cr, cx, cy, radius, angle1, angle2);
    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_stroke(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    cairo_stroke(*cr);
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_fill(lua_State* L)
{
    cairo_t** cr;
    honey_lua_parse_arguments(L, 1, 1, HONEY_USERDATA, &cr);

    cairo_fill(*cr);
    return 0;
}
			      
/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_set_color(lua_State* L)
{
    cairo_t** cr;
    float r, g, b, a;
    int choice = honey_lua_parse_arguments
        (L, 2,
         4,
         HONEY_USERDATA, &cr,
         HONEY_NUMBER, &r, HONEY_NUMBER, &g, HONEY_NUMBER, &b,
         5,
         HONEY_USERDATA, &cr,
         HONEY_NUMBER, &r, HONEY_NUMBER, &g, HONEY_NUMBER, &b, HONEY_NUMBER, &a);

    if (choice == 0)
        cairo_set_source_rgb(*cr, r, g, b);
    else
        cairo_set_source_rgba(*cr, r, g, b, a);

    return 0;
}

/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */

int honey_cairo_set_line_width(lua_State* L)
{
    cairo_t** cr;
    float width;
    honey_lua_parse_arguments(L, 1, 2, HONEY_USERDATA, &cr, HONEY_NUMBER, &width);

    cairo_set_line_width(*cr, width);
    return 0;
}