#include "aixlog.hpp"

#include "hexgrid.h"


// forward declarations
bool createHexagonGrid(hexgrid hg);

// interface

bool
hgCreateHexes(hexgrid& hg)
{
	if (hg.gridT == HEXAGON) {
		if (!createHexagonGrid(hg))
			return false;
	} else {
		LOG(ERROR) << "Unhandled grid type\n";
		return false;
	}

	return true;
}

hex_info*
hgGetSingleHex(hexgrid& hg, real32 x, real32 y)
{
	Point p(x, y);
	Hex h = hex_round(pixel_to_hex(hg.hexlib_layout, p));

	for (hex_info &hxi : *hg.hex_array) {
		if (hex_equal(h, hxi.hex))
			return &hxi;
	}

	return nullptr;
}

void
hgResetHexes(hexgrid& hg)
{
	hg.start_hex = hg.current_hex = 0;

	for (hex_info &hxi : *hg.hex_array) {
		hxi.selected = false;
		hxi.current_color = hxi.stored_color;
	}
}

void
hgUpdateHexFill(hexgrid& hg, int32 x, int32 y)
{
	hex_info *hxi = hgGetSingleHex(hg, x, y);
	if (hxi && (hxi != hg.current_hex) && hg.start_hex)
	{
		hg.current_hex = hxi;
		int l = hex_distance(hg.start_hex->hex, hg.current_hex->hex);

		for (hex_info &h : *hg.hex_array)
		{
			if (hex_distance(hg.start_hex->hex, h.hex) <= l)
			{
				h.selected = true;
				h.current_color = hg.selected_fill_color;
			}
			else
			{
				h.selected = false;
				h.current_color = h.stored_color;
			}
		}
	}
}

void
hgUpdateHexLineDraw(hexgrid& hg, int32 x, int32 y)
{
	hex_info *hxi = hgGetSingleHex(hg, x, y);
	if (hxi && (hxi != hg.current_hex) && hg.start_hex)
	{
		hg.current_hex = hxi;
		vector<Hex> hexLine = hex_linedraw(hg.start_hex->hex, hxi->hex);

		for (hex_info &h1 : *hg.hex_array)
		{
			for (uint i = 0; i < hexLine.size(); i++)
			{
				Hex h2 = hexLine[i];
				if (hex_equal(h1.hex, h2))
				{
					h1.selected = true;
					h1.current_color = hg.selected_fill_color;
					break;
				}
				else if (i == hexLine.size() - 1)
				{
					h1.selected = false;
					h1.current_color = h1.stored_color;
				}
			}
		}
	}
}

void
hgUpdateHexConeFill(hexgrid& hg, int32 x, int32 y, float cone_angle, std::vector<Point>& debug_vertices)
{
	hex_info *hxi = hgGetSingleHex(hg, x, y);
	if (hxi && (hxi != hg.current_hex) && hg.start_hex)
	{
		hg.current_hex = hxi;

		// TODO: Remove debug code here and from gooey.h
		Point p1(hg.start_hex->XPos, hg.start_hex->YPos);
		Point p2(hg.current_hex->XPos, hg.current_hex->YPos);
		real64 angle = std::atan2(p2.y - p1.y, p2.x - p1.x);
		real64 len = std::hypot(p2.y - p1.y, p2.x - p1.x);
		real64 coneAngle = cone_angle * M_PI / 180; // M_PI is non-standard and may not be portable

		real64 x1 = len * std::cos(angle);
		real64 y1 = len * std::sin(angle);
		// top of cone
		real64 topX = x1 * std::cos(coneAngle) - y1 * std::sin(coneAngle) + p1.x;
		real64 topY = x1 * std::sin(coneAngle) + y1 * std::cos(coneAngle) + p1.y;
		// bottom of cone
		real64 botX = x1 * std::cos(coneAngle) + y1 * std::sin(coneAngle) + p1.x;
		real64 botY = x1 * std::sin(-1 * coneAngle) + y1 * std::cos(coneAngle) + p1.y;

		Point test_p;
		Point vert2 = Point(botX, botY);
		Point vert4 = Point(topX, topY);
		std::vector<Point> vertices = {p1, vert2, p2, vert4};

		for (hex_info &h : *hg.hex_array)
		{
			test_p.x = h.XPos;
			test_p.y = h.YPos;

			if (crossingTest(vertices, test_p))
			{
				h.selected = true;
				h.current_color = hg.selected_fill_color;
			}
			else
			{
				h.selected = false;
				h.current_color = h.stored_color;
			}
		}

		debug_vertices[0] = p1;
		debug_vertices[1] = vert2;
		debug_vertices[2] = p2;
		debug_vertices[3] = vert4;
	}
}

void
hgUpdateColorBuffer(gl_buffer& color_buf, std::vector<hex_info>* hex_array)
{
	uint buf_idx = 0;
	uint buf_len_per_hex = 54; // NOTE: 6 triangles * 3 vertices * 3 floats
	GLfloat color[3];

	for (uint i = 0; i < hex_array->size(); i++) {
		buf_idx = i * buf_len_per_hex;
		hex_info hxi = (*hex_array)[i];

		// TODO: check performance of this since we call multiple times per frame
		// 	maybe can cache glfloat triplets somewhere
		utilConvertColor(color, hxi.current_color);

		for (uint j = 0; j < buf_len_per_hex; j += 3) {
			color_buf.buffer[buf_idx + j] = color[0];
			color_buf.buffer[buf_idx + j + 1] = color[1];
			color_buf.buffer[buf_idx + j + 2] = color[2];
		}
	}
}

// internal

bool
createHexagonGrid(hexgrid hg)
{
	if (hg.hex_array == nullptr) {
		LOG(ERROR) << "hg.hex_array is not initialized\n";
		return false;
	}

	int hr = hg.hex_radius;
	int nhr = hg.hex_radius * -1;

	for (int q = nhr; q <= hr; q++)
	{
		int r1 = std::max(nhr, -q - hr);
		int r2 = std::min(hr, -q + hr);

		for (int r = r1; r <= r2; r++)
		{
			hex_info hxi;
			hxi.hexID = (int32) hg.hex_array->size();
			hxi.hex.q = q; hxi.hex.r = r; hxi.hex.s = -q-r;
			Point p = hex_to_pixel(hg.hexlib_layout, hxi.hex);
			hxi.XPos = p.x;
			hxi.YPos = p.y;
			hxi.current_color = hg.fill_color;
			hxi.stored_color = hg.fill_color;
			hxi.vertices = polygon_corners(hg.hexlib_layout, hxi.hex);
			hxi.vertices.shrink_to_fit();
			hg.hex_array->push_back(hxi);
		}
	}

	return true;
}