/*
 * Copyright (C) 2021  P. J. McDermott
 *
 * This file is part of Maze Fight
 *
 * Maze Fight is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Maze Fight is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Maze Fight.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <SDL.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "../tk.h"
#include "widget.h"

struct mftk_grid {
	struct mftk_widget   parent;
	int                  rows;
	int                  cols;
	struct mftk_widget **children;
	int                 *alignments;
	int                 *rows_h;
	int                 *cols_w;
	int                  row_spacing;
	int                  col_spacing;
};

static void
_mftk_grid_layout(struct mftk_widget *w)
{
	struct mftk_grid *g = (struct mftk_grid *) w;
	int               r;
	int               c;
	int               sz;
	int               max_sz;

	w->h = 0;
	for (r = 0; r < g->rows; ++r) {
		max_sz = 0;
		for (c = 0; c < g->cols; ++c) {
			mftk_widget_layout(g->children[r * g->cols + c]);
			sz = g->children[r * g->cols + c]->h;
			if (sz > max_sz) {
				max_sz = sz;
			}
		}
		g->rows_h[r] = max_sz;
		if (r > 0) {
			w->h += g->row_spacing;
		}
		w->h += max_sz;
	}

	w->w = 0;
	for (c = 0; c < g->cols; ++c) {
		max_sz = 0;
		for (r = 0; r < g->rows; ++r) {
			sz = g->children[r * g->cols + c]->w;
			if (sz > max_sz) {
				max_sz = sz;
			}
		}
		g->cols_w[c] = max_sz;
		if (c > 0) {
			w->w += g->col_spacing;
		}
		w->w += max_sz;
	}
}

static void
_mftk_grid_index(struct mftk_widget *w, struct mftk_window *win)
{
	struct mftk_grid *g = (struct mftk_grid *) w;
	int               i;

	for (i = 0; i < g->rows * g->cols; ++i) {
		mftk_widget_index(g->children[i], win);
	}
}

static int
_mftk_grid_mouse_event(struct mftk_widget *w, SDL_Event *e, int x, int y)
{
	struct mftk_grid   *g = (struct mftk_grid *) w;
	SDL_Point           p;
	SDL_Rect            rect;
	int                 r;
	int                 cy;
	int                 c;
	int                 cx;
	int                 i;
	struct mftk_widget *ch;

	switch (e->type) {
		case SDL_MOUSEBUTTONUP:
			p.x = e->button.x;
			p.y = e->button.y;
			cy = y;
			for (r = 0; r < g->rows; ++r) {
				if (r > 0) {
					cy += g->row_spacing;
				}
				cx = x;
				for (c = 0; c < g->cols; ++c) {
					if (c > 0) {
						cx += g->col_spacing;
					}
					i = r * g->cols + c;
					ch = g->children[i];
					rect.x = cx;
					rect.y = cy;
					if (g->alignments != NULL) {
						if (g->alignments[i] &
							MFTK_GRID_HALIGN_C) {
							rect.x += (g->cols_w[c]
									- ch->w)
								/ 2;
						} else if (g->alignments[i] &
							MFTK_GRID_HALIGN_R) {
							rect.x += g->cols_w[c] -
								ch->w;
						}
						if (g->alignments[i] &
							MFTK_GRID_VALIGN_M) {
							rect.y += (g->rows_h[r]
									- ch->h)
								/ 2;
						} else if (g->alignments[i] &
							MFTK_GRID_VALIGN_B) {
							rect.y += g->rows_h[r] -
								ch->h;
						}
					}
					rect.w = ch->w;
					rect.h = ch->h;
					if (SDL_PointInRect(&p, &rect)
							== SDL_TRUE) {
						return mftk_widget_mouse_event(
								ch, e,
								rect.x, rect.y);
					}
					cx += g->cols_w[c];
				}
				cy += g->rows_h[r];
			}
			break;
		default:
			break;
	}

	return 0;
}

static int
_mftk_grid_render(struct mftk_widget *w, SDL_Renderer *renderer, int x, int y)
{
	struct mftk_grid   *g = (struct mftk_grid *) w;
	int                 e = 0;
	int                 r;
	int                 cy;
	int                 c;
	int                 cx;
	int                 i;
	struct mftk_widget *ch;
	int                 chx;
	int                 chy;

	cy = y;
	for (r = 0; r < g->rows; ++r) {
		if (r > 0) {
			cy += g->row_spacing;
		}
		cx = x;
		for (c = 0; c < g->cols; ++c) {
			if (c > 0) {
				cx += g->col_spacing;
			}
			i = r * g->cols + c;
			ch = g->children[i];
			chx = cx;
			chy = cy;
			if (g->alignments != NULL) {
				if (g->alignments[i] & MFTK_GRID_HALIGN_C) {
					chx += (g->cols_w[c] - ch->w) / 2;
				} else if (g->alignments[i]&MFTK_GRID_HALIGN_R){
					chx += g->cols_w[c] - ch->w;
				}
				if (g->alignments[i] & MFTK_GRID_VALIGN_M) {
					chy += (g->rows_h[r] - ch->h) / 2;
				} else if (g->alignments[i]&MFTK_GRID_VALIGN_B){
					chy += g->rows_h[r] - ch->h;
				}
			}
			if (mftk_widget_render(ch, renderer, chx, chy) < 0) {
				e = -1;
			}
			cx += g->cols_w[c];
		}
		cy += g->rows_h[r];
	}

	return e;
}

static void
_mftk_grid_destroy(struct mftk_widget *w)
{
	struct mftk_grid *g = (struct mftk_grid *) w;
	int               r;
	int               c;

	for (r = 0; r < g->rows; ++r) {
		for (c = 0; c < g->cols; ++c) {
			mftk_widget_destroy(&g->children[r * g->cols + c]);
		}
	}

	free(g->children);
	if (g->alignments != NULL) {
		free(g->alignments);
	}
	free(g->rows_h);
	free(g->cols_w);
}

struct mftk_widget *
mftk_grid_new_a(int rows, int cols, int row_spacing, int col_spacing,
		struct mftk_widget **children, int *alignments)
{
	struct mftk_widget *w;
	struct mftk_grid   *g;
	int                 i;

	mftk_widget_init_container(w, g, grid);

	g->rows_h = calloc(rows, sizeof(*g->rows_h));
	if (g->rows_h == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create widget: %s",
				strerror(errno));
		free(g->children);
		free(g);
		return NULL;
	}
	g->cols_w = calloc(cols, sizeof(*g->cols_w));
	if (g->cols_w == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create widget: %s",
				strerror(errno));
		free(g->rows_h);
		free(g->children);
		free(g);
		return NULL;
	}

	g->rows        = rows;
	g->cols        = cols;
	g->row_spacing = row_spacing;
	g->col_spacing = col_spacing;
	g->children    = children;
	g->alignments  = alignments;

	for (i = 0; i < rows * cols; ++i) {
		children[i]->container = w;
	}

	return w;
}

struct mftk_widget *
mftk_grid_new(int rows, int cols, int row_spacing, int col_spacing, ...)
{
	struct mftk_widget **children;
	int                 *alignments;
	struct mftk_widget  *w;
	va_list              ap;
	int                  r;
	int                  c;

	children = calloc(rows * cols, sizeof(*children));
	if (children == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create widget: %s",
				strerror(errno));
		return NULL;
	}
	alignments = calloc(rows * cols, sizeof(*alignments));
	if (alignments == NULL) {
		SDL_LogError(SDL_LOG_CATEGORY_APPLICATION,
				"Couldn't create widget: %s",
				strerror(errno));
		return NULL;
	}

	va_start(ap, col_spacing);
	for (r = 0; r < rows; ++r) {
		for (c = 0; c < cols; ++c) {
			children[r*cols + c] = va_arg(ap, struct mftk_widget *);
			alignments[r*cols + c] = va_arg(ap, int);
		}
	}
	va_end(ap);

	w = mftk_grid_new_a(rows, cols, row_spacing, col_spacing, children,
			alignments);
	if (w == NULL) {
		free(children);
		free(alignments);
	}

	return w;
}