/* $Id$ */


#include "stdafx.h"
#include "openttd.h"
#include "gui.h"
#include "window_gui.h"
#include "viewport_func.h"
#include "news.h"
#include "settings_type.h"
#include "transparency.h"
#include "strings_func.h"
#include "window_func.h"
#include "date_func.h"
#include "vehicle_base.h"
#include "sound_func.h"
#include "string_func.h"
#include "widgets/dropdown_func.h"

#include "table/sprites.h"
#include "table/strings.h"

/** @file news_gui.cpp
 *
 * News system is realized as a FIFO queue (in an array)
 * The positions in the queue can't be rearranged, we only access
 * the array elements through pointers to the elements. Once the
 * array is full, the oldest entry (\a _oldest_news) is being overwritten
 * by the newest (\a _latest_news).
 *
 * \verbatim
 * oldest                   current   lastest
 *  |                          |         |
 * [O------------F-------------C---------L           ]
 *               |
 *            forced
 * \endverbatim
 *
 * Of course by using an array we can have situations like
 *
 * \verbatim
 * [----L          O-----F---------C-----------------]
 * This is where we have wrapped around the array and have
 * (MAX_NEWS - O) + L news items
 * \endverbatim
 */

/** Number of news items in the FIFO queue */
#define MAX_NEWS 30
#define NB_WIDG_PER_SETTING 4

typedef byte NewsID;
#define INVALID_NEWS 255

NewsItem _statusbar_news_item;
uint32 _news_display_opt;
bool _news_ticker_sound;
static NewsItem _news_items[MAX_NEWS];      ///< The news FIFO queue
static NewsID _current_news = INVALID_NEWS; ///< points to news item that should be shown next
static NewsID _oldest_news = 0;             ///< points to first item in fifo queue
static NewsID _latest_news = INVALID_NEWS;  ///< points to last item in fifo queue

/** Forced news item.
 * Users can force an item by accessing the history or "last message".
 * If the message being shown was forced by the user, its index is stored in
 * _forced_news. Otherwise, \a _forced_news variable is INVALID_NEWS. */
static NewsID _forced_news = INVALID_NEWS;

static byte _total_news = 0; ///< Number of news items in FIFO queue @see _news_items

void DrawNewsNewVehicleAvail(Window *w);
void DrawNewsBankrupcy(Window *w);
static void MoveToNextItem();

StringID GetNewsStringNewVehicleAvail(const NewsItem *ni);
StringID GetNewsStringBankrupcy(const NewsItem *ni);

static DrawNewsCallbackProc * const _draw_news_callback[] = {
	DrawNewsNewVehicleAvail,  ///< DNC_VEHICLEAVAIL
	DrawNewsBankrupcy,        ///< DNC_BANKRUPCY
};

extern GetNewsStringCallbackProc * const _get_news_string_callback[];
GetNewsStringCallbackProc * const _get_news_string_callback[] = {
	GetNewsStringNewVehicleAvail,  ///< DNC_VEHICLEAVAIL
	GetNewsStringBankrupcy,        ///< DNC_BANKRUPCY
};

/** Initialize the news-items data structures */
void InitNewsItemStructs()
{
	memset(_news_items, 0, sizeof(_news_items));
	_current_news = INVALID_NEWS;
	_oldest_news = 0;
	_latest_news = INVALID_NEWS;
	_forced_news = INVALID_NEWS;
	_total_news = 0;
}

void DrawNewsBorder(const Window *w)
{
	int left = 0;
	int right = w->width - 1;
	int top = 0;
	int bottom = w->height - 1;

	GfxFillRect(left, top, right, bottom, 0xF);

	GfxFillRect(left, top, left, bottom, 0xD7);
	GfxFillRect(right, top, right, bottom, 0xD7);
	GfxFillRect(left, top, right, top, 0xD7);
	GfxFillRect(left, bottom, right, bottom, 0xD7);

	DrawString(left + 2, top + 1, STR_00C6, TC_FROMSTRING);
}

static void NewsWindowProc(Window *w, WindowEvent *e)
{
	switch (e->event) {
	case WE_CREATE: { // If chatbar is open at creation time, we need to go above it
		const Window *w1 = FindWindowById(WC_SEND_NETWORK_MSG, 0);
		w->message.msg = (w1 != NULL) ? w1->height : 0;
	} break;

	case WE_PAINT: {
		const NewsItem *ni = WP(w, news_d).ni;
		ViewPort *vp;

		switch (ni->display_mode) {
			case NM_NORMAL:
			case NM_THIN: {
				DrawNewsBorder(w);

				DrawString(2, 1, STR_00C6, TC_FROMSTRING);

				SetDParam(0, ni->date);
				DrawStringRightAligned(428, 1, STR_01FF, TC_FROMSTRING);

				if (!(ni->flags & NF_VIEWPORT)) {
					CopyInDParam(0, ni->params, lengthof(ni->params));
					DrawStringMultiCenter(215, ni->display_mode == NM_NORMAL ? 76 : 56,
						ni->string_id, w->width - 4);
				} else {
					/* Back up transparency options to draw news view */
					TransparencyOptionBits to_backup = _transparency_opt;
					_transparency_opt = 0;
					DrawWindowViewport(w);
					_transparency_opt = to_backup;

					/* Shade the viewport into gray, or color*/
					vp = w->viewport;
					GfxFillRect(vp->left - w->left, vp->top - w->top,
						vp->left - w->left + vp->width - 1, vp->top - w->top + vp->height - 1,
						(ni->flags & NF_INCOLOR ? PALETTE_TO_TRANSPARENT : PALETTE_TO_STRUCT_GREY) | (1 << USE_COLORTABLE)
					);

					CopyInDParam(0, ni->params, lengthof(ni->params));
					DrawStringMultiCenter(w->width / 2, 20, ni->string_id, w->width - 4);
				}
				break;
			}

			case NM_CALLBACK: {
				_draw_news_callback[ni->callback](w);
				break;
			}

			default: {
				DrawWindowWidgets(w);
				if (!(ni->flags & NF_VIEWPORT)) {
					CopyInDParam(0, ni->params, lengthof(ni->params));
					DrawStringMultiCenter(140, 38, ni->string_id, 276);
				} else {
					DrawWindowViewport(w);
					CopyInDParam(0, ni->params, lengthof(ni->params));
					DrawStringMultiCenter(w->width / 2, w->height - 16, ni->string_id, w->width - 4);
				}
				break;
			}
		}
	} break;

	case WE_CLICK: {
		switch (e->we.click.widget) {
		case 1: {
			NewsItem *ni = WP(w, news_d).ni;
			DeleteWindow(w);
			ni->duration = 0;
			_forced_news = INVALID_NEWS;
		} break;
		case 0: {
			NewsItem *ni = WP(w, news_d).ni;
			if (ni->flags & NF_VEHICLE) {
				Vehicle *v = GetVehicle(ni->data_a);
				ScrollMainWindowTo(v->x_pos, v->y_pos);
			} else if (ni->flags & NF_TILE) {
				if (!ScrollMainWindowToTile(ni->data_a) && ni->data_b != 0)
					ScrollMainWindowToTile(ni->data_b);
			}
		} break;
		}
	} break;

	case WE_KEYPRESS:
		if (e->we.keypress.keycode == WKC_SPACE) {
			/* Don't continue. */
			e->we.keypress.cont = false;
			DeleteWindow(w);
		}
		break;

	case WE_MESSAGE: // The chatbar has notified us that is was either created or closed
		switch (e->we.message.msg) {
			case WE_CREATE: w->message.msg = e->we.message.wparam; break;
			case WE_DESTROY: w->message.msg = 0; break;
		}
		break;

	case WE_TICK: { // Scroll up newsmessages from the bottom in steps of 4 pixels
		int diff;
		int y = max(w->top - 4, _screen.height - w->height - 12 - w->message.msg);
		if (y == w->top) return;

		if (w->viewport != NULL)
			w->viewport->top += y - w->top;

		diff = Delta(w->top, y);
		w->top = y;

		SetDirtyBlocks(w->left, w->top - diff, w->left + w->width, w->top + w->height);
	} break;
	}
}

/**
 * Return the correct index in the pseudo-fifo
 * queue and deals with overflows when increasing the index
 */
static inline NewsID increaseIndex(NewsID i)
{
	assert(i != INVALID_NEWS);
	return (i + 1) % MAX_NEWS;
}

/**
 * Return the correct index in the pseudo-fifo
 * queue and deals with overflows when decreasing the index
 */
static inline NewsID decreaseIndex(NewsID i)
{
	assert(i != INVALID_NEWS);
	return (i + MAX_NEWS - 1) % MAX_NEWS;
}

/**
 * Add a new newsitem to be shown.
 * @param string String to display, can have special values based on parameter \a flags
 * @param flags various control bits that will show various news-types. See macro NEWS_FLAGS()
 * @param data_a news-specific value based on news type
 * @param data_b news-specific value based on news type
 * @note flags exists of 4 byte-sized extra parameters.
 *  -# Bits  0 -  7 display_mode, any of the NewsMode enums (NM_)
 *  -# Bits  8 - 15 news flags, any of the NewsFlags enums (NF_)
 *  -# Bits 16 - 23 news category, any of the NewsType enums (NT_)
 *  -# Bits 24 - 31 news callback function, any of the NewsCallback enums (DNC_)
 *
 * If the display mode is NM_CALLBACK, special news is shown and parameter
 * \a string has a special meaning.
 *  - For DNC_TRAINAVAIL, DNC_ROADAVAIL, DNC_SHIPAVAIL, DNC_AIRCRAFTAVAIL messages: StringID is
 *    the index of the engine that is shown
 *
 *  - For DNC_BANKRUPCY: bytes 0-3 of StringID contains the player that is in trouble,
 *    and 4-7 contains what kind of bankrupcy message is shown.
 *    @see NewsBankrupcy
 *
 * @see NewsMode
 * @see NewsFlags
 * @see NewsType
 * @see NewsCallback
 */
void AddNewsItem(StringID string, uint32 flags, uint data_a, uint data_b)
{
	NewsID l_news;

	if (_game_mode == GM_MENU) return;

	/* check the rare case that the oldest (to be overwritten) news item is open */
	if (_total_news == MAX_NEWS && (_oldest_news == _current_news || _oldest_news == _forced_news))
		MoveToNextItem();

	if (_total_news < MAX_NEWS) _total_news++;

	/* Increase _latest_news. If we have no news yet, use _oldest news as an
	 * index. We cannot use 0 as _oldest_news can jump around due to
	 * DeleteVehicleNews */
	l_news = _latest_news;
	_latest_news = (_latest_news == INVALID_NEWS) ? _oldest_news : increaseIndex(_latest_news);

	/* If the fifo-buffer is full, overwrite the oldest entry */
	if (l_news != INVALID_NEWS && _latest_news == _oldest_news) {
		assert(_total_news == MAX_NEWS);
		_oldest_news = increaseIndex(_oldest_news);
	}

	/*DEBUG(misc, 0, "+cur %3d, old %2d, lat %3d, for %3d, tot %2d",
	  _current_news, _oldest_news, _latest_news, _forced_news, _total_news);*/

	/* Add news to _latest_news */
	{
		Window *w;
		NewsItem *ni = &_news_items[_latest_news];
		memset(ni, 0, sizeof(*ni));

		ni->string_id = string;
		ni->display_mode = (byte)flags;
		ni->flags = (byte)(flags >> 8);

		/* show this news message in color? */
		if (_cur_year >= _patches.colored_news_year) ni->flags |= NF_INCOLOR;

		ni->type = (byte)(flags >> 16);
		ni->callback = (byte)(flags >> 24);
		ni->data_a = data_a;
		ni->data_b = data_b;
		ni->date = _date;
		CopyOutDParam(ni->params, 0, lengthof(ni->params));

		w = FindWindowById(WC_MESSAGE_HISTORY, 0);
		if (w == NULL) return;
		SetWindowDirty(w);
		w->vscroll.count = _total_news;
	}
}


/**
 * Maximum age of news items.
 * Don't show item if it's older than x days, corresponds with NewsType in news.h
 * @see NewsType
 */
static const byte _news_items_age[NT_END] = {
	60,  ///< NT_ARRIVAL_PLAYER
	60,  ///< NT_ARRIVAL_OTHER
	90,  ///< NT_ACCIDENT
	60,  ///< NT_COMPANY_INFO
	90,  ///< NT_OPENCLOSE
	30,  ///< NT_ECONOMY
	30,  ///< NT_INDUSTRY_PLAYER
	30,  ///< NT_INDUSTRY_OTHER
	30,  ///< NT_INDUSTRY_NOBODY
	150, ///< NT_ADVICE
	30,  ///< NT_NEW_VEHICLES
	90,  ///< NT_ACCEPTANCE
	180, ///< NT_SUBSIDIES
	60   ///< NT_GENERAL
};


static const Widget _news_type13_widgets[] = {
{      WWT_PANEL,   RESIZE_NONE,    15,     0,   429,     0,   169, 0x0, STR_NULL},
{      WWT_PANEL,   RESIZE_NONE,    15,     0,    10,     0,    11, 0x0, STR_NULL},
{   WIDGETS_END},
};

static WindowDesc _news_type13_desc = {
	WDP_CENTER, 476, 430, 170, 430, 170,
	WC_NEWS_WINDOW, WC_NONE,
	WDF_DEF_WIDGET,
	_news_type13_widgets,
	NewsWindowProc
};

static const Widget _news_type2_widgets[] = {
{      WWT_PANEL,   RESIZE_NONE,    15,     0,   429,     0,   129, 0x0, STR_NULL},
{      WWT_PANEL,   RESIZE_NONE,    15,     0,    10,     0,    11, 0x0, STR_NULL},
{   WIDGETS_END},
};

static WindowDesc _news_type2_desc = {
	WDP_CENTER, 476, 430, 130, 430, 130,
	WC_NEWS_WINDOW, WC_NONE,
	WDF_DEF_WIDGET,
	_news_type2_widgets,
	NewsWindowProc
};

static const Widget _news_type0_widgets[] = {
{      WWT_PANEL,   RESIZE_NONE,     5,     0,   279,    14,    86, 0x0,              STR_NULL},
{   WWT_CLOSEBOX,   RESIZE_NONE,     5,     0,    10,     0,    13, STR_00C5,         STR_018B_CLOSE_WINDOW},
{    WWT_CAPTION,   RESIZE_NONE,     5,    11,   279,     0,    13, STR_012C_MESSAGE, STR_NULL},
{      WWT_INSET,   RESIZE_NONE,     5,     2,   277,    16,    64, 0x0,              STR_NULL},
{   WIDGETS_END},
};

static WindowDesc _news_type0_desc = {
	WDP_CENTER, 476, 280, 87, 280, 87,
	WC_NEWS_WINDOW, WC_NONE,
	WDF_DEF_WIDGET,
	_news_type0_widgets,
	NewsWindowProc
};

static const SoundFx _news_sounds[NT_END] = {
	SND_1D_APPLAUSE,	///< NT_ARRIVAL_PLAYER
	SND_1D_APPLAUSE,	///< NT_ARRIVAL_OTHER
	SND_BEGIN,		///< NT_ACCIDENT
	SND_BEGIN,		///< NT_COMPANY_INFO
	SND_BEGIN,		///< NT_OPENCLOSE
	SND_BEGIN,		///< NT_ECONOMY
	SND_BEGIN,		///< NT_INDUSTRY_PLAYER
	SND_BEGIN,		///< NT_INDUSTRY_OTHER
	SND_BEGIN,		///< NT_INDUSTRY_NOBODY
	SND_BEGIN,		///< NT_ADVICE
	SND_1E_OOOOH,		///< NT_NEW_VEHICLES
	SND_BEGIN,		///< NT_ACCEPTANCE
	SND_BEGIN,		///< NT_SUBSIDIES
	SND_BEGIN,		///< NT_GENERAL
};

const char *_news_display_name[NT_END] = {
	"arrival_player",
	"arrival_other",
	"accident",
	"company_info",
	"openclose",
	"economy",
	"production_player",
	"production_other",
	"production_nobody",
	"advice",
	"new_vehicles",
	"acceptance",
	"subsidies",
	"general",
};

/**
 * Get the value of an item of the news-display settings. This is
 * a little tricky since on/off/summary must use 2 bits to store the value
 * @param item the item whose value is requested
 * @return return the found value which is between 0-2
 */
static inline byte GetNewsDisplayValue(byte item)
{
	assert(item < NT_END && GB(_news_display_opt, item * 2, 2) <= 2);
	return GB(_news_display_opt, item * 2, 2);
}

/**
 * Set the value of an item in the news-display settings. This is
 * a little tricky since on/off/summary must use 2 bits to store the value
 * @param item the item whose value is being set
 * @param val new value
 */
static inline void SetNewsDisplayValue(byte item, byte val)
{
	assert(item < NT_END && val <= 2);
	SB(_news_display_opt, item * 2, 2, val);
}

/** Open up an own newspaper window for the news item */
static void ShowNewspaper(NewsItem *ni)
{
	Window *w;
	SoundFx sound;
	int top;
	ni->flags &= ~NF_FORCE_BIG;
	ni->duration = 555;

	sound = _news_sounds[ni->type];
	if (sound != 0) SndPlayFx(sound);

	top = _screen.height;
	switch (ni->display_mode) {
		case NM_NORMAL:
		case NM_CALLBACK: {
			_news_type13_desc.top = top;
			w = AllocateWindowDesc(&_news_type13_desc);
			if (ni->flags & NF_VIEWPORT)
				AssignWindowViewport(w, 2, 58, 0x1AA, 0x6E,
					ni->data_a | (ni->flags & NF_VEHICLE ? 0x80000000 : 0), ZOOM_LVL_NEWS);
			break;
		}

		case NM_THIN: {
			_news_type2_desc.top = top;
			w = AllocateWindowDesc(&_news_type2_desc);
			if (ni->flags & NF_VIEWPORT)
				AssignWindowViewport(w, 2, 58, 0x1AA, 0x46,
					ni->data_a | (ni->flags & NF_VEHICLE ? 0x80000000 : 0), ZOOM_LVL_NEWS);
			break;
		}

		default: {
			_news_type0_desc.top = top;
			w = AllocateWindowDesc(&_news_type0_desc);
			if (ni->flags & NF_VIEWPORT)
				AssignWindowViewport(w, 3, 17, 0x112, 0x2F,
					ni->data_a | (ni->flags & NF_VEHICLE ? 0x80000000 : 0), ZOOM_LVL_NEWS);
			break;
		}
	}

	/*DEBUG(misc, 0, " cur %3d, old %2d, lat %3d, for %3d, tot %2d",
	  _current_news, _oldest_news, _latest_news, _forced_news, _total_news);*/

	WP(w, news_d).ni = &_news_items[_forced_news == INVALID_NEWS ? _current_news : _forced_news];
	w->flags4 |= WF_DISABLE_VP_SCROLL;
}

/** Show news item in the ticker */
static void ShowTicker(const NewsItem *ni)
{
	Window *w;

	if (_news_ticker_sound) SndPlayFx(SND_16_MORSE);

	_statusbar_news_item = *ni;
	w = FindWindowById(WC_STATUS_BAR, 0);
	if (w != NULL) WP(w, def_d).data_1 = 360;
}


/**
 * Are we ready to show another news item?
 * Only if nothing is in the newsticker and no newspaper is displayed
 */
static bool ReadyForNextItem()
{
	const Window *w;
	NewsID item = (_forced_news == INVALID_NEWS) ? _current_news : _forced_news;
	NewsItem *ni;

	if (item >= MAX_NEWS) return true;
	ni = &_news_items[item];

	/* Ticker message
	 * Check if the status bar message is still being displayed? */
	w = FindWindowById(WC_STATUS_BAR, 0);
	if (w != NULL && WP(w, const def_d).data_1 > -1280) return false;

	/* Newspaper message, decrement duration counter */
	if (ni->duration != 0) ni->duration--;

	/* neither newsticker nor newspaper are running */
	return (ni->duration == 0 || FindWindowById(WC_NEWS_WINDOW, 0) == NULL);
}

/** Move to the next news item */
static void MoveToNextItem()
{
	DeleteWindowById(WC_NEWS_WINDOW, 0);
	_forced_news = INVALID_NEWS;

	/* if we're not at the last item, then move on */
	if (_current_news != _latest_news) {
		NewsItem *ni;

		_current_news = (_current_news == INVALID_NEWS) ? _oldest_news : increaseIndex(_current_news);
		ni = &_news_items[_current_news];

		/* check the date, don't show too old items */
		if (_date - _news_items_age[ni->type] > ni->date) return;

		switch (GetNewsDisplayValue(ni->type)) {
			default: NOT_REACHED();
			case 0: { // Off - show nothing only a small reminder in the status bar
				Window *w = FindWindowById(WC_STATUS_BAR, 0);

				if (w != NULL) {
					WP(w, def_d).data_2 = 91;
					SetWindowDirty(w);
				}
				break;
			}

			case 1: // Summary - show ticker, but if forced big, cascade to full
				if (!(ni->flags & NF_FORCE_BIG)) {
					ShowTicker(ni);
					break;
				}
				/* Fallthrough */

			case 2: // Full - show newspaper
				ShowNewspaper(ni);
				break;
		}
	}
}

void NewsLoop()
{
	/* no news item yet */
	if (_total_news == 0) return;

	if (ReadyForNextItem()) MoveToNextItem();
}

/** Do a forced show of a specific message */
static void ShowNewsMessage(NewsID i)
{
	if (_total_news == 0) return;

	/* Delete the news window */
	DeleteWindowById(WC_NEWS_WINDOW, 0);

	/* setup forced news item */
	_forced_news = i;

	if (_forced_news != INVALID_NEWS) {
		NewsItem *ni = &_news_items[_forced_news];
		ni->duration = 555;
		ni->flags |= NF_FORCE_BIG;
		DeleteWindowById(WC_NEWS_WINDOW, 0);
		ShowNewspaper(ni);
	}
}

/** Show previous news item */
void ShowLastNewsMessage()
{
	if (_forced_news == INVALID_NEWS) {
		/* Not forced any news yet, show the current one, unless a news window is
		 * open (which can only be the current one), then show the previous item */
		const Window *w = FindWindowById(WC_NEWS_WINDOW, 0);
		ShowNewsMessage((w == NULL || (_current_news == _oldest_news)) ? _current_news : decreaseIndex(_current_news));
	} else if (_forced_news == _oldest_news) {
		/* We have reached the oldest news, start anew with the latest */
		ShowNewsMessage(_latest_news);
	} else {
		/* 'Scrolling' through news history show each one in turn */
		ShowNewsMessage(decreaseIndex(_forced_news));
	}
}


/* return news by number, with 0 being the most
 * recent news. Returns INVALID_NEWS if end of queue reached. */
static NewsID getNews(NewsID i)
{
	if (i >= _total_news) return INVALID_NEWS;

	if (_latest_news < i) {
		i = _latest_news + MAX_NEWS - i;
	} else {
		i = _latest_news - i;
	}

	i %= MAX_NEWS;
	return i;
}

/**
 * Draw an unformatted news message truncated to a maximum length. If
 * length exceeds maximum length it will be postfixed by '...'
 * @param x,y position of the string
 * @param color the color the string will be shown in
 * @param *ni NewsItem being printed
 * @param maxw maximum width of string in pixels
 */
static void DrawNewsString(int x, int y, uint16 color, const NewsItem *ni, uint maxw)
{
	char buffer[512], buffer2[512];
	const char *ptr;
	char *dest;
	StringID str;

	if (ni->display_mode == NM_CALLBACK) {
		str = _get_news_string_callback[ni->callback](ni);
	} else {
		CopyInDParam(0, ni->params, lengthof(ni->params));
		str = ni->string_id;
	}

	GetString(buffer, str, lastof(buffer));
	/* Copy the just gotten string to another buffer to remove any formatting
	 * from it such as big fonts, etc. */
	ptr  = buffer;
	dest = buffer2;
	WChar c_last = '\0';
	for (;;) {
		WChar c = Utf8Consume(&ptr);
		if (c == 0) break;
		/* Make a space from a newline, but ignore multiple newlines */
		if (c == '\n' && c_last != '\n') {
			dest[0] = ' ';
			dest++;
		} else if (c == '\r') {
			dest[0] = dest[1] = dest[2] = dest[3] = ' ';
			dest += 4;
		} else if (IsPrintable(c)) {
			dest += Utf8Encode(dest, c);
		}
		c_last = c;
	}

	*dest = '\0';
	/* Truncate and show string; postfixed by '...' if neccessary */
	DoDrawStringTruncated(buffer2, x, y, color, maxw);
}


static void MessageHistoryWndProc(Window *w, WindowEvent *e)
{
	switch (e->event) {
	case WE_PAINT: {
		int y = 19;
		NewsID p, show;

		SetVScrollCount(w, _total_news);
		DrawWindowWidgets(w);

		if (_total_news == 0) break;
		show = min(_total_news, w->vscroll.cap);

		for (p = w->vscroll.pos; p < w->vscroll.pos + show; p++) {
			/* get news in correct order */
			const NewsItem *ni = &_news_items[getNews(p)];

			SetDParam(0, ni->date);
			DrawString(4, y, STR_SHORT_DATE, TC_WHITE);

			DrawNewsString(82, y, TC_WHITE, ni, w->width - 95);
			y += 12;
		}
		break;
	}

	case WE_CLICK:
		switch (e->we.click.widget) {
		case 3: {
			int y = (e->we.click.pt.y - 19) / 12;
			NewsID p = getNews(y + w->vscroll.pos);

			if (p == INVALID_NEWS) break;

			ShowNewsMessage(p);
			break;
		}
		}
		break;

	case WE_RESIZE:
		w->vscroll.cap += e->we.sizing.diff.y / 12;
		break;
	}
}

static const Widget _message_history_widgets[] = {
{   WWT_CLOSEBOX,   RESIZE_NONE,    13,     0,    10,     0,    13, STR_00C5,            STR_018B_CLOSE_WINDOW},
{    WWT_CAPTION,  RESIZE_RIGHT,    13,    11,   387,     0,    13, STR_MESSAGE_HISTORY, STR_018C_WINDOW_TITLE_DRAG_THIS},
{  WWT_STICKYBOX,     RESIZE_LR,    13,   388,   399,     0,    13, 0x0,                 STR_STICKY_BUTTON},
{      WWT_PANEL,     RESIZE_RB,    13,     0,   387,    14,   139, 0x0,                 STR_MESSAGE_HISTORY_TIP},
{  WWT_SCROLLBAR,    RESIZE_LRB,    13,   388,   399,    14,   127, 0x0,                 STR_0190_SCROLL_BAR_SCROLLS_LIST},
{  WWT_RESIZEBOX,   RESIZE_LRTB,    13,   388,   399,   128,   139, 0x0,                 STR_RESIZE_BUTTON},
{   WIDGETS_END},
};

static const WindowDesc _message_history_desc = {
	240, 22, 400, 140, 400, 140,
	WC_MESSAGE_HISTORY, WC_NONE,
	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_UNCLICK_BUTTONS | WDF_STICKY_BUTTON | WDF_RESIZABLE,
	_message_history_widgets,
	MessageHistoryWndProc
};

/** Display window with news messages history */
void ShowMessageHistory()
{
	Window *w;

	DeleteWindowById(WC_MESSAGE_HISTORY, 0);
	w = AllocateWindowDesc(&_message_history_desc);

	if (w != NULL) {
		w->vscroll.cap = 10;
		w->vscroll.count = _total_news;
		w->resize.step_height = 12;
		w->resize.height = w->height - 12 * 6; // minimum of 4 items in the list, each item 12 high
		w->resize.step_width = 1;
		w->resize.width = 200; // can't make window any smaller than 200 pixel
		SetWindowDirty(w);
	}
}


/** News settings window widget offset constants */
enum {
	WIDGET_NEWSOPT_DROP_SUMMARY = 4,  ///< Dropdown that adjusts at once the level for all settings
	WIDGET_NEWSOPT_SOUNDTICKER  = 6,  ///< Button activating sound on events
	WIDGET_NEWSOPT_START_OPTION = 8,  ///< First widget that is part of a group [<] .. [.]
};

/**
 * Setup the disabled/enabled buttons in the message window
 * If the value is 'off' disable the [<] widget, and enable the [>] one
 * Same-wise for all the others. Starting value of 4 is the first widget
 * group. These are grouped as [<][>] .. [<][>], etc.
 * @param w Window been used
 * @param value to set in the widget
 * @param element index of the group of widget to set
 */
static void SetMessageButtonStates(Window *w, byte value, int element)
{
	element *= NB_WIDG_PER_SETTING;

	w->SetWidgetDisabledState(element + WIDGET_NEWSOPT_START_OPTION, value == 0);
	w->SetWidgetDisabledState(element + WIDGET_NEWSOPT_START_OPTION + 2, value == 2);
}

/**
 * Event handler of the Message Options window
 * @param w window pointer
 * @param e event been triggered
 */
static void MessageOptionsWndProc(Window *w, WindowEvent *e)
{
	static const StringID message_opt[] = {STR_OFF, STR_SUMMARY, STR_FULL, INVALID_STRING_ID};

	/* WP(w, def_d).data_1 stores state of the ALL on/off/summary button */
	switch (e->event) {
		case WE_CREATE: {
			uint32 val = _news_display_opt;
			uint32 all_val;
			int i;

			/* Set up the initial disabled buttons in the case of 'off' or 'full' */
			all_val = val & 0x3;
			for (i = 0; i < NT_END; i++, val >>= 2) {
				SetMessageButtonStates(w, val & 0x3, i);
				/* If the value doesn't match the ALL-button value, set the ALL-button value to 'off' */
				if ((val & 0x3) != all_val) all_val = 0;
			}
			/* If all values are the same value, the ALL-button will take over this value */
			WP(w, def_d).data_1 = all_val;
		} break;

		case WE_PAINT: {
			uint32 val = _news_display_opt;
			int i, y;

			if (_news_ticker_sound) w->LowerWidget(WIDGET_NEWSOPT_SOUNDTICKER);

			w->widget[WIDGET_NEWSOPT_DROP_SUMMARY].data = message_opt[WP(w, def_d).data_1];
			DrawWindowWidgets(w);

			/* Draw the string of each setting on each button. */
			for (i = 0, y = 26; i < NT_END; i++, y += 12, val >>= 2) {
				/* 51 comes from 13 + 89 (left and right of the button)+1, shiefted by one as to get division,
				 * which will give centered position */
				DrawStringCentered(51, y + 1, message_opt[val & 0x3], TC_BLACK);
			}
		} break;

		case WE_CLICK:
			switch (e->we.click.widget) {
				case WIDGET_NEWSOPT_DROP_SUMMARY: // Dropdown menu for all settings
					ShowDropDownMenu(w, message_opt, WP(w, def_d).data_1, WIDGET_NEWSOPT_DROP_SUMMARY, 0, 0);
					break;

				case WIDGET_NEWSOPT_SOUNDTICKER: // Change ticker sound on/off
					_news_ticker_sound ^= 1;
					w->ToggleWidgetLoweredState(e->we.click.widget);
					w->InvalidateWidget(e->we.click.widget);
					break;

				default: { // Clicked on the [<] .. [>] widgets
					int wid = e->we.click.widget - WIDGET_NEWSOPT_START_OPTION;
					if (wid >= 0 && wid < (NB_WIDG_PER_SETTING * NT_END)) {
						int element = wid / NB_WIDG_PER_SETTING;
						byte val = (GetNewsDisplayValue(element) + ((wid % NB_WIDG_PER_SETTING) ? 1 : -1)) % 3;

						SetMessageButtonStates(w, val, element);
						SetNewsDisplayValue(element, val);
						SetWindowDirty(w);
					}
				} break;
			} break;

		case WE_DROPDOWN_SELECT: { // Select all settings for newsmessages
			int i;

			WP(w, def_d).data_1 = e->we.dropdown.index;

			for (i = 0; i < NT_END; i++) {
				SetMessageButtonStates(w, e->we.dropdown.index, i);
				SetNewsDisplayValue(i, e->we.dropdown.index);
			}
			SetWindowDirty(w);
		} break;
	}
}


/*
* The news settings window widgets
*
* Main part of the window is a list of news-setting lines, one for each news category.
* Each line is constructed by an expansion of the \c NEWS_SETTINGS_LINE macro
*/

/**
* Macro to construct one news-setting line in the news-settings window.
* One line consists of four widgets, namely
* - A [<] button
* - A [...] label
* - A [>] button
* - A text label describing the news category
* Horizontal positions of the widgets are hard-coded, vertical start position is (\a basey + \a linenum * \c NEWS_SETTING_BASELINE_SKIP).
* Height of one line is 12, with the text label shifted 1 pixel down.
*
* First line should be widget number WIDGET_NEWSOPT_START_OPTION
*
* @param basey: Base Y coordinate
* @param linenum: Count, news-setting is the \a linenum-th line
* @param text: StringID for the text label to display
*/
#define NEWS_SETTINGS_LINE(basey, linenum, text) \
	{ WWT_PUSHIMGBTN, RESIZE_NONE, COLOUR_YELLOW, \
	    4,  12,  basey     + linenum * NEWS_SETTING_BASELINE_SKIP,  basey + 11 + linenum * NEWS_SETTING_BASELINE_SKIP, \
	  SPR_ARROW_LEFT, STR_HSCROLL_BAR_SCROLLS_LIST}, \
	{ WWT_PUSHTXTBTN, RESIZE_NONE, COLOUR_YELLOW, \
	   13,  89,  basey     + linenum * NEWS_SETTING_BASELINE_SKIP,  basey + 11 + linenum * NEWS_SETTING_BASELINE_SKIP, \
	  STR_EMPTY, STR_NULL}, \
	{ WWT_PUSHIMGBTN, RESIZE_NONE, COLOUR_YELLOW, \
	   90,  98,  basey     + linenum * NEWS_SETTING_BASELINE_SKIP,  basey + 11 + linenum * NEWS_SETTING_BASELINE_SKIP, \
	  SPR_ARROW_RIGHT, STR_HSCROLL_BAR_SCROLLS_LIST}, \
        { WWT_TEXT, RESIZE_NONE, COLOUR_YELLOW, \
	  103, 409,  basey + 1 + linenum * NEWS_SETTING_BASELINE_SKIP,  basey + 13 + linenum * NEWS_SETTING_BASELINE_SKIP, \
	  text, STR_NULL}

static const int NEWS_SETTING_BASELINE_SKIP = 12; ///< Distance between two news-setting lines, should be at least 12


static const Widget _message_options_widgets[] = {
{ WWT_CLOSEBOX, RESIZE_NONE, COLOUR_BROWN,   0,  10,  0, 13,
	STR_00C5,                 STR_018B_CLOSE_WINDOW},
{  WWT_CAPTION, RESIZE_NONE, COLOUR_BROWN,  11, 409,  0, 13,
	STR_0204_MESSAGE_OPTIONS, STR_018C_WINDOW_TITLE_DRAG_THIS},
{    WWT_PANEL, RESIZE_NONE, COLOUR_BROWN,   0, 409, 14, 64 + NT_END * NEWS_SETTING_BASELINE_SKIP,
	0x0,                      STR_NULL},

/* Text at the top of the main panel, in black */
{    WWT_LABEL, RESIZE_NONE, COLOUR_BROWN,
	  0, 409, 13, 26,
	STR_0205_MESSAGE_TYPES,   STR_NULL},

/* General drop down and sound button, widgets WIDGET_NEWSOPT_BTN_SUMMARY and WIDGET_NEWSOPT_DROP_SUMMARY */
{  WWT_DROPDOWN, RESIZE_NONE, COLOUR_YELLOW,
	  4,  98,  34 + NT_END * NEWS_SETTING_BASELINE_SKIP,  45 + NT_END * NEWS_SETTING_BASELINE_SKIP,
	0x0, STR_NULL},

{      WWT_TEXT, RESIZE_NONE, COLOUR_YELLOW,
	103, 409,  35 + NT_END * NEWS_SETTING_BASELINE_SKIP,  47 + NT_END * NEWS_SETTING_BASELINE_SKIP,
	STR_MESSAGES_ALL, STR_NULL},

/* Below is widget WIDGET_NEWSOPT_SOUNDTICKER */
{ WWT_TEXTBTN_2, RESIZE_NONE, COLOUR_YELLOW,
	  4,  98,  46 + NT_END * NEWS_SETTING_BASELINE_SKIP,  57 + NT_END * NEWS_SETTING_BASELINE_SKIP,
	STR_02DB_OFF,  STR_NULL},

{      WWT_TEXT, RESIZE_NONE, COLOUR_YELLOW,
	103, 409,  47 + NT_END * NEWS_SETTING_BASELINE_SKIP,  59 + NT_END * NEWS_SETTING_BASELINE_SKIP,
	STR_MESSAGE_SOUND, STR_NULL},

/* List of news-setting lines (4 widgets for each line).
 * First widget must be number WIDGET_NEWSOPT_START_OPTION
 */
NEWS_SETTINGS_LINE(26, NT_ARRIVAL_PLAYER, STR_0206_ARRIVAL_OF_FIRST_VEHICLE),
NEWS_SETTINGS_LINE(26, NT_ARRIVAL_OTHER,  STR_0207_ARRIVAL_OF_FIRST_VEHICLE),
NEWS_SETTINGS_LINE(26, NT_ACCIDENT, STR_0208_ACCIDENTS_DISASTERS),
NEWS_SETTINGS_LINE(26, NT_COMPANY_INFO, STR_0209_COMPANY_INFORMATION),
NEWS_SETTINGS_LINE(26, NT_OPENCLOSE, STR_NEWS_OPEN_CLOSE),
NEWS_SETTINGS_LINE(26, NT_ECONOMY, STR_020A_ECONOMY_CHANGES),
NEWS_SETTINGS_LINE(26, NT_INDUSTRY_PLAYER, STR_INDUSTRY_CHANGES_SERVED_BY_PLAYER),
NEWS_SETTINGS_LINE(26, NT_INDUSTRY_OTHER, STR_INDUSTRY_CHANGES_SERVED_BY_OTHER),
NEWS_SETTINGS_LINE(26, NT_INDUSTRY_NOBODY, STR_OTHER_INDUSTRY_PRODUCTION_CHANGES),
NEWS_SETTINGS_LINE(26, NT_ADVICE, STR_020B_ADVICE_INFORMATION_ON_PLAYER),
NEWS_SETTINGS_LINE(26, NT_NEW_VEHICLES, STR_020C_NEW_VEHICLES),
NEWS_SETTINGS_LINE(26, NT_ACCEPTANCE, STR_020D_CHANGES_OF_CARGO_ACCEPTANCE),
NEWS_SETTINGS_LINE(26, NT_SUBSIDIES, STR_020E_SUBSIDIES),
NEWS_SETTINGS_LINE(26, NT_GENERAL, STR_020F_GENERAL_INFORMATION),

{   WIDGETS_END},
};

static const WindowDesc _message_options_desc = {
	270,  22,  410,  65 + NT_END * NEWS_SETTING_BASELINE_SKIP,
	           410,  65 + NT_END * NEWS_SETTING_BASELINE_SKIP,
	WC_GAME_OPTIONS, WC_NONE,
	WDF_STD_TOOLTIPS | WDF_STD_BTN | WDF_DEF_WIDGET | WDF_UNCLICK_BUTTONS,
	_message_options_widgets,
	MessageOptionsWndProc
};

void ShowMessageOptions()
{
	DeleteWindowById(WC_GAME_OPTIONS, 0);
	AllocateWindowDesc(&_message_options_desc);
}


void DeleteVehicleNews(VehicleID vid, StringID news)
{
	NewsID n;

	for (n = _oldest_news; _latest_news != INVALID_NEWS; n = increaseIndex(n)) {
		const NewsItem *ni = &_news_items[n];

		if (ni->flags & NF_VEHICLE &&
				ni->data_a == vid &&
				(news == INVALID_STRING_ID || ni->string_id == news)) {
			Window *w;

			/* If we delete a forced news and it is just before the current news
			 * then we need to advance to the next news (if any) */
			if (_forced_news == n) MoveToNextItem();
			if (_forced_news == INVALID_NEWS && _current_news == n) MoveToNextItem();
			_total_news--;

			/* If this is the last news item, invalidate _latest_news */
			if (_total_news == 0) {
				assert(_latest_news == _oldest_news);
				_latest_news = INVALID_NEWS;
			}

			/* Since we only imitate a FIFO removing an arbitrary element does need
			 * some magic. Remove the item by shifting head towards the tail. eg
			 *    oldest    remove  last
			 *        |        |     |
			 * [------O--------n-----L--]
			 * will become (change dramatized to make clear)
			 * [---------O-----------L--]
			 * We also need an update of the current, forced and visible (open window)
			 * news's as this shifting could change the items they were pointing to */
			if (_total_news != 0) {
				w = FindWindowById(WC_NEWS_WINDOW, 0);
				NewsID visible_news = (w != NULL) ? (NewsID)(WP(w, news_d).ni - _news_items) : INVALID_NEWS;

				for (NewsID i = n;; i = decreaseIndex(i)) {
					_news_items[i] = _news_items[decreaseIndex(i)];

					if (i != _latest_news) {
						if (i == _current_news) _current_news = increaseIndex(_current_news);
						if (i == _forced_news) _forced_news = increaseIndex(_forced_news);
						if (i == visible_news) WP(w, news_d).ni = &_news_items[increaseIndex(visible_news)];
					}

					if (i == _oldest_news) break;
				}
				_oldest_news = increaseIndex(_oldest_news);
			}

			/*DEBUG(misc, 0, "-cur %3d, old %2d, lat %3d, for %3d, tot %2d",
			  _current_news, _oldest_news, _latest_news, _forced_news, _total_news);*/

			w = FindWindowById(WC_MESSAGE_HISTORY, 0);
			if (w != NULL) {
				SetWindowDirty(w);
				w->vscroll.count = _total_news;
			}
		}

		if (n == _latest_news) break;
	}
}