degvi/View.c

#include "init.h"
#include <assert.h>
#include <stdlib.h>
#include <stdio.h>
#include "View.h"

View View_create(Window window, Text text, int tabWidth)
{
	View this;

	this = malloc(sizeof(struct View_struct));
	if (this == NULL) {
		fprintf(stderr, "malloc failed\n");
		exit(EXIT_FAILURE);
	}

	this->window = window;
	this->text = text;
	this->tabWidth = tabWidth;
	this->origin = 0;
	this->cursorLine = 0;
	this->cursorCharacter = 0;

	return this;
}

void View_destroy(View this)
{
	if (this == NULL) {
		return;
	}

	free(this);
}

void View_setTabWidth(View this, int tabWidth)
{
	this->tabWidth = tabWidth;
}

static void toView(View this, int lineIndex, int characterIndex, int *resultX, int *resultY)
{
	int x;
	int y;
	int j;

	assert(lineIndex >= this->origin);

	y = 0;
	for (j = this->origin; j <= lineIndex; j++) {
		Line line;
		int i;

		line = Text_getLine(this->text, j);
		x = 0;
		for (i = 0; i < Line_size(line); i++) {
			Character c;

			if (j == lineIndex && i == characterIndex) {
				break;
			}

			c = Line_getCharacter(line, i);
			if (c == '\t') {
				x = x / this->tabWidth * this->tabWidth + this->tabWidth;
			} else {
				x += Character_width(c);
			}
			if (x >= Window_width(this->window)) {
				x = 0;
				y++;
			}
		}
		if (j < lineIndex) {
			y++;
		}
	}
	*resultX = x;
	*resultY = y;
}

void View_updateCursorPosition(View this)
{
	int x;
	int y;

	if (Text_size(this->text) < 1) {
		x = 0;
		y = 0;
	} else {
		toView(this, this->cursorLine, this->cursorCharacter, &x, &y);
	}
	Window_setCursorPosition(this->window, x, y);
}

void View_paint(View this)
{
	int lineIndex;
	int y;
	int i;

	lineIndex = this->origin;
	y = 0;
	for (;;) {
		int x;
		int k;

		Window_setCursorPosition(this->window, 0, y);
		x = 0;
		if (lineIndex < Text_size(this->text)) {
			Line line;

			line = Text_getLine(this->text, lineIndex);
			lineIndex++;
			for (i = 0; i < Line_size(line); i++) {
				Character c;

				c = Line_getCharacter(line, i);
				if (c == '\t') {
					int x2;
					int l;

					x2 = x / this->tabWidth * this->tabWidth + this->tabWidth;
					for (l = x; l < x2; l++) {
						fputc(' ', stdout);
					}
					x = x2;
				} else {
					Character_write(c, stdout);
					x += Character_width(c);
				}

				if (x >= Window_width(this->window)) {
					x = 0;
					y++;
					if (y >= Window_height(this->window)) {
						break;
					}
					Window_setCursorPosition(this->window, 0, y);
				}
			}
		} else {
			fputc('~', stdout);
			x++;
		}

		for (k = x; k < Window_width(this->window); k++) {
			fputc(' ', stdout);
		}

		y++;
		if (y >= Window_height(this->window)) {
			break;
		}
	}
}

int View_lastLineIndex(View this)
{
	int x;
	int y;
	int j;

	if (Text_size(this->text) < 1) {
		return 0;
	}

	y = 0;
	j = this->origin;
	for (;;) {
		Line line;
		int i;

		line = Text_getLine(this->text, j);
		x = 0;
		for (i = 0; i < Line_size(line); i++) {
			Character c;

			c = Line_getCharacter(line, i);
			if (c == '\t') {
				x = x / this->tabWidth * this->tabWidth + this->tabWidth;
			} else {
				x++;
			}
			if (x >= Window_width(this->window)) {
				x = 0;
				y++;
			}
		}
		y++;
		if (y == Window_height(this->window)) {
			break;
		} else if (y > Window_height(this->window)) {
			j--;
			break;
		} else if (j >= Text_size(this->text) - 1) {
			break;
		} else {
			j++;
		}
	}
	return j;
}

void View_moveToTop(View this)
{
	this->cursorLine = 0;
	this->cursorCharacter = 0;
	this->origin = 0;
	View_paint(this);
	View_updateCursorPosition(this);
}

void View_moveToLine(View this, int index)
{
	if (Text_size(this->text) < 1) {
		return;
	}

	assert(index >= 0 && index < Text_size(this->text));

	this->cursorLine = index;
	this->cursorCharacter = 0;
	this->origin = this->cursorLine;
	View_paint(this);
	View_updateCursorPosition(this);
}

void View_moveToHead(View this)
{
	this->cursorCharacter = 0;
	View_updateCursorPosition(this);
}

void View_moveToTail(View this)
{
	Line line;

	if (Text_size(this->text) < 1) {
		return;
	}
	line = Text_getLine(this->text, this->cursorLine);
	if (Line_size(line) < 1) {
		return;
	}
	this->cursorCharacter = Line_size(line) - 1;
	View_updateCursorPosition(this);
}

void View_moveUp(View this, int repeat)
{
	int size;

	if (Text_size(this->text) < 1) {
		return;
	}

	this->cursorLine -= repeat;
	if (this->cursorLine < 0) {
		this->cursorLine = 0;
	}
	size = Line_size(Text_getLine(this->text, this->cursorLine));
	if (size < 1) {
		this->cursorCharacter = 0;
	} else if (this->cursorCharacter >= size) {
		this->cursorCharacter = size - 1;
	}
	if (this->cursorLine < this->origin) {
		this->origin = this->cursorLine;
		View_paint(this);
	}
	View_updateCursorPosition(this);
}

void View_moveDown(View this, int repeat)
{
	int size;
	int lastLine;

	if (this->cursorLine >= Text_size(this->text) - 1) {
		return;
	}

	this->cursorLine += repeat;
	if (this->cursorLine >= Text_size(this->text)) {
		this->cursorLine = Text_size(this->text) - 1;
		if (this->cursorLine < 0) {
			this->cursorLine = 0;
		}
	}
	size = Line_size(Text_getLine(this->text, this->cursorLine));
	if (size < 1) {
		this->cursorCharacter = 0;
	} else if (this->cursorCharacter >= size) {
		this->cursorCharacter = size - 1;
	}
	lastLine = View_lastLineIndex(this);
	if (this->cursorLine > lastLine) {
		this->origin += this->cursorLine - lastLine;
		View_paint(this);
	}
	View_updateCursorPosition(this);
}

void View_moveLeft(View this, int repeat)
{
	this->cursorCharacter -= repeat;
	if (this->cursorCharacter < 0) {
		this->cursorCharacter = 0;
	}
	View_updateCursorPosition(this);
}

void View_moveRight(View this, int repeat)
{
	if (Text_size(this->text) < 1) {
		return;
	}
	this->cursorCharacter += repeat;
	if (this->cursorCharacter >= Line_size(Text_getLine(this->text, this->cursorLine))) {
		this->cursorCharacter = Line_size(Text_getLine(this->text, this->cursorLine)) - 1;
		if (this->cursorCharacter < 0) {
			this->cursorCharacter = 0;
		}
	}
	View_updateCursorPosition(this);
}