/** \file server/drivers/debug.c
 * \c debug driver for LCDd.
 * This driver does does nothing more than writing a debug message when
 * any one of the driver's functions is called.
 */

/*-
 * Copyright (C) 2008, Peter Marschall
 * 		 2010, Markus Dolze
 *
 * This program 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 2 of the License, or
 * any later version.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <stdlib.h>
#include <string.h>

#include "lcd.h"
#include "debug.h"
#include "shared/report.h"


#define DEFAULT_WIDTH		LCD_DEFAULT_WIDTH
#define DEFAULT_HEIGHT		LCD_DEFAULT_HEIGHT
#define DEFAULT_CELLWIDTH	LCD_DEFAULT_CELLWIDTH
#define DEFAULT_CELLHEIGHT	LCD_DEFAULT_CELLHEIGHT
#define DEFAULT_CONTRAST	500
#define DEFAULT_BRIGHTNESS	750
#define DEFAULT_OFFBRIGHTNESS	250


/** private data for the \c debug driver */
typedef struct debug_private_data {
	char *framebuf;		/**< frame buffer */
	int width;		/**< display width in characters */
	int height;		/**< display height in characters */
	int cellwidth;		/**< character cell width */
	int cellheight;		/**< character cell height */
	int contrast;		/**< current contrast */
	int brightness;		/**< current brightness (for backlight on) */
	int offbrightness;	/**< current brightness (for backlight off) */
} PrivateData;


/* Vars for the server core */
MODULE_EXPORT char *api_version = API_VERSION;
MODULE_EXPORT int stay_in_foreground = 1;
MODULE_EXPORT int supports_multiple = 0;
MODULE_EXPORT char *symbol_prefix = "debug_";


/**
 * Initialize the driver. (Required)
 * \param drvthis  Pointer to driver structure.
 * \retval 0       Success.
 * \retval <0      Error.
 */
MODULE_EXPORT int
debug_init(Driver *drvthis)
{
	PrivateData *p;

	report(RPT_INFO, "%s()", __FUNCTION__);

	/* Allocate and store private data */
	p = (PrivateData *) calloc(1, sizeof(PrivateData));
	if (p == NULL)
		return -1;
	if (drvthis->store_private_ptr(drvthis, p))
		return -1;

	p->width = DEFAULT_WIDTH;
	p->height = DEFAULT_HEIGHT;
	p->cellwidth = DEFAULT_CELLWIDTH;
	p->cellheight = DEFAULT_CELLHEIGHT;
	p->contrast = DEFAULT_CONTRAST;
	p->brightness = DEFAULT_BRIGHTNESS;
	p->offbrightness = DEFAULT_OFFBRIGHTNESS;

	p->framebuf = malloc(p->width * p->height);
	if (p->framebuf == NULL) {
		report(RPT_INFO, "%s: unable to allocate framebuffer", drvthis->name);
		return -1;
	}

	debug_clear(drvthis);

	return 0;
}


/**
 * Close the driver (do necessary clean-up). (Required)
 * \param drvthis  Pointer to driver structure.
 */
MODULE_EXPORT void
debug_close(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s()", __FUNCTION__);

	if (p != NULL) {
		if (p->framebuf != NULL)
			free(p->framebuf);
		p->framebuf = NULL;

		free(p);
	}
	drvthis->store_private_ptr(drvthis, NULL);
}


/**
 * Return the display width in characters. (Required for output)
 * \param drvthis  Pointer to driver structure.
 * \return         Number of characters the display is wide.
 */
MODULE_EXPORT int
debug_width(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s()", __FUNCTION__);

	return p->width;
}


/**
 * Return the display height in characters. (Required for output)
 * \param drvthis  Pointer to driver structure.
 * \return         Number of characters the display is high.
 */
MODULE_EXPORT int
debug_height(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s()", __FUNCTION__);

	return p->height;
}


/**
 * Return the width of a character in pixels. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \return         Number of pixel columns a character cell is wide.
 */
MODULE_EXPORT int
debug_cellwidth(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s()", __FUNCTION__);

	return p->cellwidth;
}


/**
 * Return the height of a character in pixels. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \return         Number of pixel lines a character cell is high.
 */
MODULE_EXPORT int
debug_cellheight(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s()", __FUNCTION__);

	return p->cellheight;
}


/**
 * Clear the screen. (Required for output)
 * \param drvthis  Pointer to driver structure.
 */
MODULE_EXPORT void
debug_clear(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s()", __FUNCTION__);

	memset(p->framebuf, ' ', p->width * p->height);

}


/**
 * Flush data on screen to the display. (Optional)
 * \param drvthis  Pointer to driver structure.
 *
 * \note Character 0x00 may be a valid character in the frame buffer! Avoid
 * using string handling functions here (strcpy and friends).
 *
 * \note \n Note to driver developers: Drivers may write to the screen directly
 * with chr() and string() functions. However, it makes sound to have these
 * functions write to an internal frame buffer first and update the screen on
 * call to flush(), maybe with some partial/incremental update algorithm.
 * Some drivers have a second buffer to hold the actual screen content to be
 * able to compare it with the current frame buffer (double buffering). The
 * debug driver provides a simple single frame buffer implementation.
 *
 * DO NOT COPY THESE NOTES!
 */
MODULE_EXPORT void
debug_flush(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;
	int i, j;
	char out[LCD_MAX_WIDTH];

	report(RPT_INFO, "%s()", __FUNCTION__);

	/* Heading line */
	for (i = 0; i < p->width; i++) {
		out[i] = '-';
	}
	out[p->width] = 0;
	//report(RPT_DEBUG, "+%s+", out);

	/* Output each framebuffer line */
	for (i = 0; i < p->height; i++) {
		for (j = 0; j < p->width; j++) {
			out[j] = p->framebuf[j + (i * p->width)];
		}
		out[p->width] = 0;
		//report(RPT_DEBUG, "|%s|", out);

	}

	/* Trailing line */
	for (i = 0; i < p->width; i++) {
		out[i] = '-';
	}
	out[p->width] = 0;
	//report(RPT_DEBUG, "+%s+", out);
}


/**
 * Print a string on the screen at position (x,y). (Required for output)
 * The upper-left corner is (1,1), the lower-right corner is (p->width, p->height).
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param y        Vertical character position (row).
 * \param string   String that gets written.
 *
 * \see debug_flush
 */
MODULE_EXPORT void
debug_string(Driver *drvthis, int x, int y, const char string[])
{
	PrivateData *p = drvthis->private_data;
	int i;

	report(RPT_INFO, "%s(%i,%i,%.40s)", __FUNCTION__, x, y, string);

	y--;			/* Convert 1-based coords to 0-based... */
	x--;

	if ((y < 0) || (y >= p->height))
		return;

	for (i = 0; (string[i] != '\0') && (x < p->width); i++, x++) {
		if (x >= 0)	/* no write left of left border */
			p->framebuf[(y * p->width) + x] = string[i];
	}
}


/**
 * Print a character on the screen at position (x,y). (Required for output)
 * The upper-left corner is (1,1), the lower-right corner is (p->width, p->height).
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param y        Vertical character position (row).
 * \param c        Character that gets written.
 *
 * \note Keep in mind that character 0x00 may be a valid character on your
 * display and it is used by the bignum library. Avoid using string handling
 * functions here!
 *
 * \see debug_flush
 */
MODULE_EXPORT void
debug_chr(Driver *drvthis, int x, int y, char c)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_DEBUG, "%s(%i,%i,%c)", __FUNCTION__, x, y, c);

	x--;
	y--;

	if ((x >= 0) && (y >= 0) && (x < p->width) && (y < p->height))
		p->framebuf[(y * p->width) + x] = c;
}


/**
 * Draw a vertical bar bottom-up. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column) of the starting point.
 * \param y        Vertical character position (row) of the starting point.
 * \param len      Number of characters that the bar is high at 100%
 * \param promille Current height level of the bar in promille.
 * \param options  Options (currently unused).
 */
MODULE_EXPORT void
debug_vbar(Driver *drvthis, int x, int y, int len, int promille, int options)
{
	//PrivateData *p = drvthis->private_data;
	int pos;

	report(RPT_INFO, "%s(%i,%i,%i,%i,%i)", __FUNCTION__, x, y, len, promille, options);

	for (pos = 0; pos < len; pos++) {
		if (2 * pos < ((long)promille * len / 500 + 1)) {
			debug_chr(drvthis, x, y - pos, '|');
		}
		else {
			;	/* print nothing */
		}
	}
}


/**
 * Draw a horizontal bar to the right. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column) of the starting point.
 * \param y        Vertical character position (row) of the starting point.
 * \param len      Number of characters that the bar is long at 100%
 * \param promille Current length level of the bar in promille.
 * \param options  Options (currently unused).
 */
MODULE_EXPORT void
debug_hbar(Driver *drvthis, int x, int y, int len, int promille, int options)
{
	//PrivateData *p = drvthis->private_data;
	int pos;

	report(RPT_INFO, "%s(%i,%i,%i,%i,%i)", __FUNCTION__, x, y, len, promille, options);

	for (pos = 0; pos < len; pos++) {
		if (2 * pos < ((long)promille * len / 500 + 1)) {
			debug_chr(drvthis, x + pos, y, '-');
		}
		else {
			;	/* print nothing */
		}
	}
}


/**
 * Write a big number to the screen. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param num      Character to write (0 - 10 with 10 representing ':')
 */
MODULE_EXPORT void
debug_num(Driver *drvthis, int x, int num)
{
	//PrivateData *p = drvthis->private_data;
	report(RPT_INFO, "%s(%i,%i)", __FUNCTION__, x, num);
}


/**
 * Place an icon on the screen. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal character position (column).
 * \param y        Vertical character position (row).
 * \param icon     synbolic value representing the icon.
 * \retval 0       Icon has been successfully defined/written.
 * \retval <0      Server core shall define/write the icon.
 */
MODULE_EXPORT int
debug_icon(Driver *drvthis, int x, int y, int icon)
{
	//PrivateData *p = drvthis->private_data;
	report(RPT_INFO, "%s(%i,%i,%i)", __FUNCTION__, x, y, icon);

	return -1;		/* let the core do all the icon stuff */
}


/**
 * Set cursor position and state. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param x        Horizontal cursor position (column).
 * \param y        Vertical cursor position (row).
 * \param type     Appearance of the cursor
 */
MODULE_EXPORT void
debug_cursor(Driver *drvthis, int x, int y, int type)
{
	report(RPT_INFO, "%s (%i,%i,%i)", __FUNCTION__, x, y, type);
}


/**
 * Define a custom character and write it to the LCD. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param n        Custom character to define [0 - (NUM_CCs-1)].
 * \param dat      Array of 8 (=cellheight) bytes, each representing a pixel row
 *                 starting from the top to bottom.
 *                 The bits in each byte represent the pixels where the LSB
 *                 (least significant bit) is the rightmost pixel in each pixel row.
 */
MODULE_EXPORT void
debug_set_char(Driver *drvthis, int n, char *dat)
{
	//PrivateData *p = drvthis->private_data;
	report(RPT_INFO, "%s(%i,data)", __FUNCTION__, n);
}


/**
 * Get total number of custom characters available. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \return  Number of custom characters.
 */
MODULE_EXPORT int
debug_get_free_chars(Driver *drvthis)
{
	report(RPT_INFO, "%s()", __FUNCTION__);

	return 0;
}


/**
 * Get current LCD contrast. (Optional)
 * This is only the locally stored contrast, the contrast value
 * cannot be retrieved from the LCD.
 * \param drvthis  Pointer to driver structure.
 * \return         Stored contrast in promille.
 */
MODULE_EXPORT int
debug_get_contrast(Driver *drvthis)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s()", __FUNCTION__);

	return p->contrast;
}


/**
 * Change LCD contrast. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param promille New contrast value in promille.
 */
MODULE_EXPORT void
debug_set_contrast(Driver *drvthis, int promille)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s(%i)", __FUNCTION__, promille);

	p->contrast = promille;
}


/**
 * Retrieve brightness. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param state    Brightness state (on/off) for which we want the value.
 * \return         Stored brightness in promille.
 */
MODULE_EXPORT int
debug_get_brightness(Driver *drvthis, int state)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s(%i)", __FUNCTION__, state);

	return (state == BACKLIGHT_ON) ? p->brightness : p->offbrightness;
}


/**
 * Set on/off brightness. (Optional)
 * \param drvthis   Pointer to driver structure.
 * \param state     Brightness state (on/off) for which we want to store the value.
 * \param promille  New brightness in promille.
 */
MODULE_EXPORT void
debug_set_brightness(Driver *drvthis, int state, int promille)
{
	PrivateData *p = drvthis->private_data;

	report(RPT_INFO, "%s(%i,%i)", __FUNCTION__, state, promille);

	/* Check it */
	if (promille < 0 || promille > 1000)
		return;

	/* store the software value since there is not get */
	if (state == BACKLIGHT_ON) {
		p->brightness = promille;
	}
	else {
		p->offbrightness = promille;
	}
	debug_backlight(drvthis, state);
}

/**
 * Turn the backlight on or off. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param on       New backlight status.
 */
MODULE_EXPORT void
debug_backlight(Driver *drvthis, int on)
{
	//PrivateData *p = drvthis->private_data;
	report(RPT_INFO, "%s(%i)", __FUNCTION__, on);
}


/**
 * Send out-of-band data to the device. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \param value    Integer. Meaning is specific to the device
 */
MODULE_EXPORT void
debug_output(Driver *drvthis, int value)
{
	//PrivateData *p = drvthis->private_data;
	report(RPT_INFO, "%s(%i)", __FUNCTION__, value);
}


/**
 * Handle input from keyboard. (Required for input drivers)
 * \param drvthis  Pointer to driver structure.
 * \return         String representation of the key;
 *                 \c NULL if nothing available / unmapped key
 */
MODULE_EXPORT const char *
debug_get_key(Driver *drvthis)
{
	//PrivateData *p = drvthis->private_data;
	report(RPT_INFO, "%s()", __FUNCTION__);

	return NULL;
}


/**
 * Provide some information about this driver. (Optional)
 * \param drvthis  Pointer to driver structure.
 * \return         Constant string with information.
 */
MODULE_EXPORT const char *
debug_get_info(Driver *drvthis)
{
	//PrivateData *p = drvthis->private_data;
	static char *info_string = "debug driver";

	report(RPT_INFO, "%s()", __FUNCTION__);

	return info_string;
}