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Diffstat (limited to 'edit.c')
| -rw-r--r-- | edit.c | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/edit.c b/edit.c new file mode 100644 index 0000000..d90d558 --- /dev/null +++ b/edit.c @@ -0,0 +1,207 @@ +/* Copyright (C) 2020 C. McEnroe <june@causal.agency> + * + * 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 3 of the License, or + * (at your option) 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, see <https://www.gnu.org/licenses/>. + */ + +#include <assert.h> +#include <limits.h> +#include <stdbool.h> +#include <stdio.h> +#include <stdlib.h> +#include <wchar.h> +#include <wctype.h> + +#include "chat.h" + +enum { Cap = 512 }; +static wchar_t buf[Cap]; +static size_t len; +static size_t pos; + +char *editBuffer(size_t *mbsPos) { + static char mbs[MB_LEN_MAX * Cap]; + + const wchar_t *ptr = buf; + size_t mbsLen = wcsnrtombs(mbs, &ptr, pos, sizeof(mbs) - 1, NULL); + assert(mbsLen != (size_t)-1); + if (mbsPos) *mbsPos = mbsLen; + + ptr = &buf[pos]; + size_t n = wcsnrtombs( + &mbs[mbsLen], &ptr, len - pos, sizeof(mbs) - mbsLen - 1, NULL + ); + assert(n != (size_t)-1); + mbsLen += n; + + mbs[mbsLen] = '\0'; + return mbs; +} + +static struct { + wchar_t buf[Cap]; + size_t len; +} cut; + +static bool reserve(size_t index, size_t count) { + if (len + count > Cap) return false; + memmove(&buf[index + count], &buf[index], sizeof(*buf) * (len - index)); + len += count; + return true; +} + +static void delete(size_t index, size_t count) { + if (index + count > len) return; + if (count > 1) { + memcpy(cut.buf, &buf[index], sizeof(*buf) * count); + cut.len = count; + } + memmove( + &buf[index], &buf[index + count], sizeof(*buf) * (len - index - count) + ); + len -= count; +} + +static struct { + size_t pos; + size_t pre; + size_t len; +} tab; + +static void tabComplete(size_t id) { + if (!tab.len) { + tab.pos = pos; + while (tab.pos && buf[tab.pos - 1] != L' ') tab.pos--; + if (tab.pos == pos) return; + tab.pre = pos - tab.pos; + tab.len = tab.pre; + } + + char mbs[MB_LEN_MAX * Cap]; + const wchar_t *ptr = &buf[tab.pos]; + size_t n = wcsnrtombs(mbs, &ptr, tab.pre, sizeof(mbs) - 1, NULL); + assert(n != (size_t)-1); + mbs[n] = '\0'; + + const char *comp = complete(id, mbs); + if (!comp) comp = complete(id, mbs); + if (!comp) { + tab.len = 0; + return; + } + + wchar_t wcs[Cap]; + n = mbstowcs(wcs, comp, sizeof(wcs)); + assert(n != (size_t)-1); + if (tab.pos + n + 2 > Cap) { + completeReject(); + tab.len = 0; + return; + } + + delete(tab.pos, tab.len); + if (wcs[0] != L'/' && !tab.pos) { + tab.len = n + 2; + reserve(tab.pos, tab.len); + buf[tab.pos + n + 0] = L':'; + buf[tab.pos + n + 1] = L' '; + } else if ( + tab.pos >= 2 && (buf[tab.pos - 2] == L':' || buf[tab.pos - 2] == L',') + ) { + tab.len = n + 2; + reserve(tab.pos, tab.len); + buf[tab.pos - 2] = L','; + buf[tab.pos + n + 0] = L':'; + buf[tab.pos + n + 1] = L' '; + } else { + tab.len = n + 1; + reserve(tab.pos, tab.len); + buf[tab.pos + n] = L' '; + } + memcpy(&buf[tab.pos], wcs, sizeof(*wcs) * n); + pos = tab.pos + tab.len; +} + +static void tabAccept(void) { + completeAccept(); + tab.len = 0; +} + +static void tabReject(void) { + completeReject(); + tab.len = 0; +} + +void edit(size_t id, enum Edit op, wchar_t ch) { + size_t init = pos; + switch (op) { + break; case EditHead: pos = 0; + break; case EditTail: pos = len; + break; case EditPrev: if (pos) pos--; + break; case EditNext: if (pos < len) pos++; + break; case EditPrevWord: { + if (pos) pos--; + while (pos && !iswspace(buf[pos - 1])) pos--; + } + break; case EditNextWord: { + if (pos < len) pos++; + while (pos < len && !iswspace(buf[pos])) pos++; + } + + break; case EditDeleteHead: delete(0, pos); pos = 0; + break; case EditDeleteTail: delete(pos, len - pos); + break; case EditDeletePrev: if (pos) delete(--pos, 1); + break; case EditDeleteNext: delete(pos, 1); + break; case EditDeletePrevWord: { + if (!pos) break; + size_t word = pos - 1; + while (word && !iswspace(buf[word - 1])) word--; + delete(word, pos - word); + pos = word; + } + break; case EditDeleteNextWord: { + if (pos == len) break; + size_t word = pos + 1; + while (word < len && !iswspace(buf[word])) word++; + delete(pos, word - pos); + } + break; case EditPaste: { + if (reserve(pos, cut.len)) { + memcpy(&buf[pos], cut.buf, sizeof(*buf) * cut.len); + pos += cut.len; + } + } + + break; case EditInsert: { + if (reserve(pos, 1)) { + buf[pos++] = ch; + } + } + break; case EditComplete: { + tabComplete(id); + return; + } + break; case EditEnter: { + tabAccept(); + command(id, editBuffer(NULL)); + len = pos = 0; + return; + } + } + + if (pos < init) { + tabReject(); + } else { + tabAccept(); + } +} |