#include "engine.h"
#include "tilemap.h"
#include "corelib/input.h"
#include "corelib/render.h"
#include "corelib/assets.h"
#include "corelib/layers.h"
#include "SDL2/SDL_mouse.h"
#include "SDL2/SDL_scancode.h"
#include "ui.h"

int cursor_tile = 1;
int dragging = 0;
int drawing = 0;
sprite_t cursor;
spritesheet_t world_sheet;
tileset_t tileset;
tilemap_t tilemap = {
	.width = 0,.height = 0,
	.x=0,.y=0
};

void on_save_key(int down) {
	if(down) save_tilemap(&tilemap, "tilemap.csv");
}

void on_load_key(int down) {
	if(down) load_tilemap(&tilemap, "tilemap.csv");
}

void on_clear_key(int down) {
	if(down) {
		for(int i = 0; i < tilemap.height * tilemap.width; ++i) {
			tilemap.tiles[i] = 0;
		}
	}
}

void on_cycle_tile(int axis) {
	cursor_tile += axis;
	if(cursor_tile <= 0) {
		cursor_tile = 1;
	}
	int size = tileset.size;
	if(cursor_tile >= size) {
		cursor_tile = size-1;
	}
	if(tileset.size >= cursor_tile && 0 < cursor_tile) {
		cursor = tileset.set[cursor_tile-1].sprite;
	}
}

void on_quit_key(int down) {
	if(down) {
		g_context.running = 0;
	}
}

void on_click(int down) {
	drawing = down;
}

void on_erase(int down) {
	drawing = -down;
}

void on_drag_world(float dx, float dy) {
	if(dragging) {
		g_active_view.x -= dx * g_active_view.width;
		g_active_view.y -= dy * g_active_view.width;
	}
}

void on_middle_mouse(int down) {
	dragging = down;
}

void on_debug_frame(int down) {
	if(down) {
		d_debug_next_frame = 1;
	}
}


void on_button_zoom(int axis) {
	if(axis != 0) {
		g_active_view.width += axis;
	}
}

void on_scroll_zoom(float delta) {
	g_active_view.width -= delta * 0.5f;
}

void load_game() {
	style.button.button = style.button.active = make_nineslice("button.png", 126, 0.01);
	world_sheet = make_spritesheet("tileset.png", 189, 189);

	tileset.set = (tile_t*)calloc(21, sizeof(tile_t));
	tileset.size = 21;
	tileset.set[0] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 0),.walkable=0};
	tileset.set[1] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 1),.walkable=0};
	tileset.set[2] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 2),.walkable=0};

	tileset.set[3] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 10),.walkable=0};
	tileset.set[4] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 11),.walkable=0};
	tileset.set[5] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 12),.walkable=0};

	tileset.set[6] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 20),.walkable=0};
	tileset.set[7] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 21),.walkable=0};
	tileset.set[8] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 22),.walkable=0};

	tileset.set[9] = (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 30),.walkable=1};
	tileset.set[10]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 31),.walkable=1};
	tileset.set[11]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 32),.walkable=1};

	tileset.set[12]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 3),.walkable=1};
	tileset.set[13]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 4),.walkable=1};
	tileset.set[14]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 5),.walkable=1};

	tileset.set[15]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 13),.walkable=1};
	tileset.set[16]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 14),.walkable=1};
	tileset.set[17]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 15),.walkable=1};

	tileset.set[18]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 23),.walkable=1};
	tileset.set[19]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 24),.walkable=1};
	tileset.set[20]= (tile_t){.sprite=sprite_from_spritesheet(&world_sheet, 25),.walkable=1};

	// register calloc'd array to be deleted with free(...)
	add_arbitrary_asset(tileset.set, &free);

	tilemap.width = tilemap.height = 128;
	on_cycle_tile(0);

	input_init();
	add_key_listener(SDL_SCANCODE_UNKNOWN, SDL_SCANCODE_W, &on_save_key);
	add_key_listener(SDL_SCANCODE_UNKNOWN, SDL_SCANCODE_R, &on_load_key);
	add_key_listener(SDL_SCANCODE_UNKNOWN, SDL_SCANCODE_C, &on_clear_key);
	add_key_listener(SDL_SCANCODE_UNKNOWN, SDL_SCANCODE_Q, &on_quit_key);
	add_key_listener(SDL_SCANCODE_A, SDL_SCANCODE_D, &on_cycle_tile);
	add_key_listener(SDL_SCANCODE_UNKNOWN, SDL_SCANCODE_TAB, &on_debug_frame);
	add_key_listener(SDL_SCANCODE_MINUS, SDL_SCANCODE_EQUALS, &on_button_zoom);
	add_mouse_button_listener(SDL_BUTTON_LMASK, &on_click);
	add_mouse_button_listener(SDL_BUTTON_RMASK, &on_erase);
	add_mouse_button_listener(SDL_BUTTON_MMASK, &on_middle_mouse);
	add_mouse_listener(&on_drag_world);
	add_scroll_listener(&on_scroll_zoom);
}

void start_game() {
	g_active_view.width = 21;
	on_clear_key(1);
}

void update_game() {
	if(drawing == 1) {
		drawing = 2;
	}

	float fx, fy;
	mouse_world_position(&fx, &fy);
	cursor.x = floor(fx); cursor.y = floor(fy);
	if(drawing) {
		int x, y;
		x = floorf(fx);
		y = floorf(fy);
		if(x >= 0 && y >= 0 && x < tilemap.width && y < tilemap.height) {
			if(drawing > 0) {
				set_tile(&tilemap, x, y, cursor_tile);
			} else {
				set_tile(&tilemap, x, y, 0);
			}
		}
	}

	rectshape_t world_outline = {
		tilemap.x, tilemap.y, (float)tilemap.width, (float)tilemap.height,
		0.01f, RLAYER_TILEMAP-1, {0,0,0,0}, {255, 255, 255, 255}
	};
	rectshape_t cursor_outline = {
		cursor.x, cursor.y, 1.0f, 1.0f, 0.01f, RLAYER_SPRITES-1,
		{0, 0, 0, 0}, {255, 255, 255, 255}
	};

	draw_rect(&world_outline);
	draw_rect(&cursor_outline);
	draw_sprite(&cursor);
	draw_tilemap(&tilemap, &tileset);
}

void update_ui() {
	update_input();

	nineslice_t sliced = style.button.active;
	sliced.rect = (SDL_FRect){0, 0, 0.1, 0.1};
	sliced.depth = RLAYER_UI - 20;
	draw_sliced(&sliced);

	const int offset_selected = cursor_tile - 1;

	rectshape_t selected_tile_rect = (rectshape_t) {
		offset_selected * 0.015f, 0.f, 0.015f, 0.015f, 0.001f, RLAYER_UI-10,
		{0,0,0,0}, {255, 255, 255, 255}
	};
	draw_rect(&selected_tile_rect);

	rectshape_t shape = (rectshape_t) {
		0.0f, 0.0f, 1.f, 0.015f, 0, RLAYER_UI,
		{100,100,100,255}, {0,0,0,0}
	};
	draw_rect(&shape);

	float mx, my;
	mouse_screen_position(&mx, &my);
	for(int i = 0; i < tileset.size; ++i) {
		// make a copy of the reference sprite and adjust it to fit the ui
		sprite_t sprite = tileset.set[i].sprite;
		sprite.depth = RLAYER_UI-5;
		sprite.x = i * 0.015f; sprite.y = 0;
		sprite.sx = 0.015f; sprite.sy = 0.015f;
		float amx=mx-sprite.x, amy=my-sprite.y;
		draw_sprite(&sprite);

		// allow user to select tiles with mouse
		if(amx >= 0 && amy >= 0 && amx < sprite.sx && amy < sprite.sy) {
			if(drawing == 1) {
				drawing = 0;
				cursor_tile = i+1;
				on_cycle_tile(0);
			}
		}
	}
}

void game_exit() {}