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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include "qb.h"
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#include "text.h"
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int qb_running = 1;
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typedef struct doc_line {
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char *line;
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int allocated, stored;
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struct doc_line *prev, *next;
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} doc_line_t;
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static doc_line_t *active_doc;
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static int total_lines = 1;
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static int cursor_x = 0;
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static int cursor_y = 0;
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static int scroll_x = 0;
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static int scroll_y = 0;
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static SDL_Keycode shift_table[][2] = {
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{SDLK_QUOTE, SDLK_QUOTEDBL},
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{SDLK_COMMA, SDLK_LESS},
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{SDLK_MINUS, SDLK_UNDERSCORE},
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{SDLK_PERIOD, SDLK_GREATER},
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{SDLK_SLASH, SDLK_QUESTION},
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{SDLK_0, SDLK_RIGHTPAREN},
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{SDLK_1, SDLK_EXCLAIM},
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{SDLK_2, SDLK_AT},
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{SDLK_3, SDLK_HASH},
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{SDLK_4, SDLK_DOLLAR},
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{SDLK_5, SDLK_PERCENT},
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{SDLK_6, SDLK_CARET},
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{SDLK_7, SDLK_AMPERSAND},
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{SDLK_8, SDLK_ASTERISK},
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{SDLK_9, SDLK_LEFTPAREN},
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{SDLK_SEMICOLON, SDLK_COLON},
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{SDLK_LEFTBRACKET, '{'},
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{SDLK_BACKSLASH, '|'},
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{SDLK_RIGHTBRACKET, '}'},
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{SDLK_BACKQUOTE, '~'},
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{SDLK_EQUALS, SDLK_PLUS},
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};
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static int min(int a, int b) {
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if (a < b) {
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return a;
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}
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return b;
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}
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static doc_line_t *create_doc_line(void) {
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doc_line_t *d = malloc(sizeof(*d));
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memset(d, 0, sizeof(*d));
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d->line = malloc(8);
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d->allocated = 8;
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return d;
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}
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static void free_doc_line(doc_line_t *d) {
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free(d->line);
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free(d);
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}
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static doc_line_t *get_current_doc_line(void) {
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doc_line_t *d = active_doc;
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for (int y = 0; y < cursor_y; ++y) {
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d = d->next;
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}
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return d;
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}
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static void ensure_available(doc_line_t *d, int required) {
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int allocated = d->allocated;
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while (allocated < d->stored + required) {
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allocated *= 2;
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}
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if (allocated == d->allocated) {
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return;
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}
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char *line = malloc(allocated);
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memcpy(line, d->line, d->stored);
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free(d->line);
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d->line = line;
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d->allocated = allocated;
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}
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static void insert_character(doc_line_t *d, int offset, char c) {
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ensure_available(d, 1);
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bcopy(d->line + offset, d->line + offset + 1, d->stored - offset);
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d->line[offset] = c;
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++d->stored;
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}
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static void split_line(doc_line_t *d, int offset) {
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doc_line_t *n = create_doc_line();
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n->next = d->next;
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n->prev = d;
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d->next = n;
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n->stored = d->stored - offset;
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ensure_available(n, n->stored);
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memcpy(n->line, d->line + offset, n->stored);
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d->stored -= n->stored;
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++total_lines;
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}
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static void delete_at(doc_line_t *d, int offset, int dir) {
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/* dir should be -1 (backspace) or 0 (delete) */
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if (dir == -1 && offset == 0) {
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doc_line_t *p = d->prev;
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if (!p) {
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/* WRONG
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* WAY
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* GO BACK */
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return;
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}
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--cursor_y;
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cursor_x = p->stored;
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ensure_available(p, d->stored);
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memcpy(p->line + p->stored, d->line, d->stored);
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p->next = d->next;
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p->stored += d->stored;
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if (d->next) {
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d->next->prev = p;
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}
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free_doc_line(d);
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--total_lines;
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} else if (dir == -1) {
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/* offset > 0 */
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bcopy(d->line + offset, d->line + offset - 1, d->stored - offset);
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--d->stored;
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--cursor_x;
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} else if (offset == d->stored) {
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/* dir == 0 */
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doc_line_t *n = d->next;
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if (!n) {
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return;
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}
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ensure_available(d, n->stored);
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memcpy(d->line + d->stored, n->line, n->stored);
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d->stored += n->stored;
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d->next = n->next;
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if (n->next) {
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n->next->prev = d;
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}
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free_doc_line(n);
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--total_lines;
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} else {
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/* dir == 0, offset < d->stored */
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bcopy(d->line + offset + 1, d->line + offset, d->stored - offset - 1);
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--d->stored;
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}
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}
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static char get_character(SDL_Keycode sym, Uint16 mod) {
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if (sym >= SDLK_a && sym <= SDLK_z) {
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if (mod & (KMOD_SHIFT | KMOD_CAPS)) {
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return (char) (sym - ('a' - 'A'));
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}
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return (char) sym;
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}
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if (mod & KMOD_SHIFT) {
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for (int i = 0; i < sizeof(shift_table); ++i) {
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if (shift_table[i][0] == sym) {
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return shift_table[i][1];
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}
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}
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}
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return (char) sym;
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}
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static int is_printable_key(SDL_Keycode sym) {
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return sym >= SDLK_SPACE && sym <= SDLK_z;
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}
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void render(void) {
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for (int i = 0; i < 80 * 25; ++i) {
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screen[i] = 0x1700;
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}
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/* Render the menu. */
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for (int x = 0; x < 80; ++x) {
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screen[x] = 0x7000;
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}
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const char *menu_options[] = {
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"File",
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"Edit",
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"View",
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"Search",
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"Run",
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"Debug",
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"Calls",
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"Options",
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NULL,
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};
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int offset = 2;
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for (int i = 0; ; ++i) {
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if (!menu_options[i]) {
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break;
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}
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int len = strlen(menu_options[i]);
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for (int j = 0; j < len; ++j) {
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screen[0 * 80 + offset + 1 + j] = 0x7000 | (menu_options[i][j]);
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}
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offset += len + 2;
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}
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screen[0 * 80 + 74] = 0x7000 + 'H';
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screen[0 * 80 + 75] = 0x7000 + 'e';
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screen[0 * 80 + 76] = 0x7000 + 'l';
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screen[0 * 80 + 77] = 0x7000 + 'p';
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/* Render the titlebar. */
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screen[1 * 80 + 0] = 0x17da;
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for (int x = 1; x < 79; ++x) {
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screen[1 * 80 + x] = 0x17c4;
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}
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const char *file = "Untitled";
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int flen = strlen(file);
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int start = 40 - flen / 2;
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screen[1 * 80 + start - 1] = 0x7000;
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int j;
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for (j = 0; j < flen; ++j) {
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screen[1 * 80 + start + j] = 0x7000 | file[j];
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}
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screen[1 * 80 + start + j] = 0x7000;
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/* Render the little fullscreen widget at the right. */
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screen[1 * 80 + 75] = 0x17b4;
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screen[1 * 80 + 76] = 0x7112;
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screen[1 * 80 + 77] = 0x17c3;
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screen[1 * 80 + 79] = 0x17bf;
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/* Draw the editing area and borders. */
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for (int y = 2; y < 24; ++y) {
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screen[y * 80 + 0] = screen[y * 80 + 79] = 0x17b3;
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for (int x = 1; x < 79; ++x) {
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screen[y * 80 + x] = 0x1700;
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}
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}
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/* Render the editing text. */
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doc_line_t *line = active_doc;
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for (int y = 0; y < scroll_y && line; ++y, line = line->next) {}
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for (int y = 0; y < 21 && line; ++y, line = line->next) {
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for (int x = scroll_x; x < min(line->stored, 78 + scroll_x); ++x) {
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screen[(y + 2) * 80 + 1 + x - scroll_x] += line->line[x];
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}
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}
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/* Draw the vertical scrollbar. */
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screen[2 * 80 + 79] = 0x7018;
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for (int y = 3; y < 22; ++y) {
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screen[y * 80 + 79] = 0x70b0;
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}
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screen[(3 + (int)((float) cursor_y / (total_lines - 1) * (21 - 3))) * 80 + 79] = 0x0000;
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screen[22 * 80 + 79] = 0x7019;
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/* Draw the horizontal scrollbar. */
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screen[23 * 80 + 1] = 0x701b;
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for (int x = 2; x < 78; ++x) {
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screen[23 * 80 + x] = 0x70b0;
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}
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screen[23 * 80 + (int)((float) scroll_x / 178 * 75) + 2] = 0x0000;
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screen[23 * 80 + 78] = 0x701a;
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/* Draw the help line. */
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const char *footer[] = {
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"Shift+F1=Help",
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"F6=Window",
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"F2=Subs",
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"F5=Run",
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"F8=Step",
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NULL,
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};
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for (int x = 0; x < 80; ++x) {
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screen[24 * 80 + x] = 0x3000;
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}
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offset = 1;
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for (int i = 0; ; ++i) {
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if (!footer[i]) {
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break;
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}
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int len = strlen(footer[i]);
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screen[24 * 80 + offset] += '<';
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int j;
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for (j = 0; j < len; ++j) {
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screen[24 * 80 + offset + 1 + j] += footer[i][j];
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}
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screen[24 * 80 + offset + 1 + j] += '>';
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offset += len + 3;
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}
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/* Draw the ruler. */
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screen[24 * 80 + 62] += 0xb3;
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char *counter;
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asprintf(&counter, "%05d:%03d", cursor_y + 1, cursor_x + 1);
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int len = strlen(counter);
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for (int i = 0; i < len; ++i) {
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screen[24 * 80 + 70 + i] += counter[i];
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}
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free(counter);
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/* Place the cursor. */
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screen_cursor_x = cursor_x + 1 - scroll_x;
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screen_cursor_y = cursor_y + 2 - scroll_y;
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}
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static void check_scroll(void) {
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/* window height: 21 lines (2 to 22) */
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if (cursor_y < scroll_y) {
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scroll_y = cursor_y;
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} else if (cursor_y > scroll_y + 20) {
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scroll_y = cursor_y - 20;
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}
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/* window width: 78 characters (1 to 78) */
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if (cursor_x < scroll_x) {
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scroll_x = cursor_x;
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} else if (cursor_x > scroll_x + 77) {
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scroll_x = cursor_x - 77;
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}
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}
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void qb_init(void) {
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active_doc = create_doc_line();
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active_doc->line = strdup("10 PRINT \"LOL\"");
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active_doc->stored = strlen(active_doc->line);
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active_doc->allocated = active_doc->stored + 1;
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active_doc->next = create_doc_line();
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active_doc->next->prev = active_doc;
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active_doc->next->line = strdup("20 GOTO 10");
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active_doc->next->stored = strlen(active_doc->next->line);
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active_doc->next->allocated = active_doc->next->stored + 1;
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active_doc->next->next = create_doc_line();
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active_doc->next->next->prev = active_doc->next;
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total_lines = 3;
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render();
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}
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void qb_keypress(SDL_Keycode sym, Uint16 mod) {
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if (sym == SDLK_ESCAPE) {
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qb_running = 0;
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return;
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}
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if (sym == SDLK_DOWN && cursor_y < total_lines - 1) {
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++cursor_y;
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int max = get_current_doc_line()->stored;
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if (cursor_x > max) {
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cursor_x = max;
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}
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} else if (sym == SDLK_UP && cursor_y > 0) {
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--cursor_y;
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int max = get_current_doc_line()->stored;
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if (cursor_x > max) {
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cursor_x = max;
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}
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} else if (sym == SDLK_LEFT && cursor_x > 0) {
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--cursor_x;
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} else if (sym == SDLK_RIGHT) {
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if (cursor_x < get_current_doc_line()->stored) {
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++cursor_x;
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}
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} else if (is_printable_key(sym) && get_current_doc_line()->stored < 255) {
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insert_character(
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get_current_doc_line(),
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cursor_x,
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get_character(sym, mod));
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++cursor_x;
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} else if (sym == SDLK_RETURN) {
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split_line(get_current_doc_line(), cursor_x);
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cursor_x = 0;
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++cursor_y;
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} else if (sym == SDLK_BACKSPACE) {
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delete_at(get_current_doc_line(), cursor_x, -1);
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} else if (sym == SDLK_DELETE) {
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delete_at(get_current_doc_line(), cursor_x, 0);
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} else if (sym == SDLK_HOME) {
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cursor_x = 0;
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} else if (sym == SDLK_END) {
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cursor_x = get_current_doc_line()->stored;
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}
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check_scroll();
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render();
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text_refresh();
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}
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/* vim: set sw=4 et: */
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