Renamed viz -> printing, and tidied up the code a bit

1 files changed, 267 insertions, 0 deletions

diff --git a/printing.c b/printing.c
new file mode 100644
index 0000000..68faf22
--- /dev/null
+++ b/printing.c
@@ -0,0 +1,267 @@
+/*
+ * printing.c - Code for printing and visualizing matches.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "printing.h"
+#include "types.h"
+#include "utils.h"
+#include "vm.h"
+
+typedef struct match_node_s {
+    match_t *m;
+    struct match_node_s *next;
+} match_node_t;
+
+typedef struct {
+    size_t line, printed_line;
+    const char *color;
+} print_state_t;
+
+static int match_height(match_t *m)
+{
+    int height = 0;
+    for (match_t *c = m->child; c; c = c->nextsibling) {
+        int childheight = match_height(c);
+        if (childheight > height) height = childheight;
+    }
+    return 1 + height;
+}
+
+static void _visualize_matches(match_node_t *firstmatch, int depth, const char *text, size_t textlen)
+{
+    if (!firstmatch) return;
+
+    const char *V = "│"; // Vertical bar
+    const char *H = "─"; // Horizontal bar
+    const char *color = (depth % 2 == 0) ? "34" : "33";
+
+    match_t *viz = firstmatch->m;
+    for (match_node_t *p = firstmatch; p; p = p->next)
+        if (match_height(p->m) > match_height(viz))
+            viz = p->m;
+    const char *viz_type = viz->op->start;
+    size_t viz_typelen = (size_t)(viz->op->end - viz->op->start);
+
+    printf("\033[%ldG\033[%s;1m", 2*textlen+3, color);
+    for (size_t i = 0; i < viz_typelen; i++) {
+        switch (viz_type[i]) {
+            case '\n': printf("↵"); break;
+            default: printf("%c", viz_type[i]); break;
+        }
+    }
+    printf("\033[0m");
+
+    match_node_t *children = NULL;
+    match_node_t **nextchild = &children;
+
+#define RIGHT_TYPE(m) (m->m->op->end == m->m->op->start + viz_typelen && strncmp(m->m->op->start, viz_type, viz_typelen) == 0)
+    // Print nonzero-width first:
+    for (match_node_t *m = firstmatch; m; m = m->next) {
+        //tree_text = byteslice(text, tree['start'], tree['end']).replace('\n', '↵')
+        if (RIGHT_TYPE(m)) {
+            //if (m->m->op->op != VM_REF) {
+                for (match_t *c = m->m->child; c; c = c->nextsibling) {
+                    *nextchild = new(match_node_t);
+                    (*nextchild)->m = c;
+                    nextchild = &((*nextchild)->next);
+                }
+            //}
+            if (m->m->end == m->m->start) continue;
+            printf("\033[%ldG\033[0;2m%s\033[0;7;%sm", 1+2*(m->m->start - text), V, color);
+            for (const char *c = m->m->start; c < m->m->end; ++c) {
+                // TODO: newline
+                if (c > m->m->start) printf(" ");
+                // TODO: utf8
+                //while ((*c & 0xC0) != 0x80) printf("%c", *(c++));
+                printf("%c", *c);
+            }
+            printf("\033[0;2m%s\033[0m", V);
+        } else {
+            *nextchild = new(match_node_t);
+            (*nextchild)->m = m->m;
+            nextchild = &((*nextchild)->next);
+            printf("\033[%ldG\033[0;2m%s", 1+2*(m->m->start - text), V);
+            for (ssize_t i = (ssize_t)(2*(m->m->end - m->m->start)-1); i > 0; i--)
+                printf(" ");
+            if (m->m->end > m->m->start)
+                printf("\033[0;2m%s", V);
+            printf("\033[0m");
+        }
+    }
+
+    // Print stars for zero-width:
+    for (match_node_t *m = firstmatch; m; m = m->next) {
+        if (m->m->end > m->m->start) continue;
+        if (RIGHT_TYPE(m)) {
+            printf("\033[%ldG\033[7;%sm▒\033[0m", 1+2*(m->m->start - text), color);
+        } else {
+            printf("\033[%ldG\033[0;2m%s\033[0m", 1+2*(m->m->start - text), V);
+        }
+    }
+
+    printf("\n");
+
+    for (match_node_t *m = firstmatch; m; m = m->next) {
+        if (m->m->end == m->m->start) {
+            if (!RIGHT_TYPE(m))
+                printf("\033[%ldG\033[0;2m%s", 1 + 2*(m->m->start - text), V);
+        } else {
+            const char *l = "└";
+            const char *r = "┘";
+            for (match_node_t *c = children; c; c = c->next) {
+                if (c->m->start == m->m->start || c->m->end == m->m->start) l = V;
+                if (c->m->start == m->m->end   || c->m->end == m->m->end) r = V;
+            }
+            printf("\033[%ldG\033[0;2m%s", 1 + 2*(m->m->start - text), l);
+            const char *h = RIGHT_TYPE(m) ? H : " ";
+            for (ssize_t n = (ssize_t)(2*(m->m->end - m->m->start) - 1); n > 0; n--)
+                printf("%s", h);
+            printf("%s\033[0m", r);
+        }
+    }
+#undef RIGHT_TYPE
+
+    printf("\n");
+
+    if (children)
+        _visualize_matches(children, depth+1, text, textlen);
+
+    for (match_node_t *c = children, *next = NULL; c; c = next) {
+        next = c->next;
+        free(c);
+    }
+}
+
+static void _visualize_patterns(match_t *m)
+{
+    if (m->op->op == VM_REF && streq(m->op->args.s, "pattern")) {
+        m = m->child;
+        match_node_t first = {.m = m};
+        _visualize_matches(&first, 0, m->start, (size_t)(m->end - m->start));
+    } else {
+        for (match_t *c = m->child; c; c = c->nextsibling)
+            _visualize_patterns(c);
+    }
+}
+
+void visualize_match(match_t *m)
+{
+    printf("\033[?7l");
+    //match_node_t first = {.m = m};
+    //_visualize_matches(&first, 0, m->start, (m->end - m->start));
+    _visualize_patterns(m);
+    printf("\033[?7h");
+}
+
+static void print_line_number(FILE *out, print_state_t *state, print_options_t options)
+{
+    state->printed_line = state->line;
+    if (!(options & PRINT_LINE_NUMBERS)) return;
+    if (options & PRINT_COLOR)
+        fprintf(out, "\033[0;2m% 5ld\033(0\x78\033(B%s", state->line, state->color);
+    else
+        fprintf(out, "% 5ld|", state->line);
+}
+
+/*
+ * Print a match with replacements and highlighting.
+ */
+static void _print_match(FILE *out, file_t *f, match_t *m, print_state_t *state, print_options_t options)
+{
+    static const char *hl = "\033[0;31;1m";
+    const char *old_color = state->color;
+    if (m->op->op == VM_HIDE) {
+        // TODO: handle replacements?
+        for (const char *p = m->start; p < m->end; p++) {
+            if (*p == '\n') ++state->line;
+        }
+    } else if (m->op->op == VM_REPLACE) {
+        if (options & PRINT_COLOR && state->color != hl) {
+            state->color = hl;
+            fprintf(out, "%s", state->color);
+        }
+        const char *text = m->op->args.replace.text;
+        const char *end = &text[m->op->args.replace.len];
+        for (const char *r = text; r < end; ) {
+            if (*r == '@' && r[1] && r[1] != '@') {
+                ++r;
+                match_t *cap = get_capture(m, &r);
+                if (cap != NULL) {
+                    _print_match(out, f, cap, state, options);
+                    continue;
+                } else {
+                    --r;
+                }
+            }
+
+            if (state->printed_line != state->line)
+                print_line_number(out, state, options);
+
+            if (*r == '\\') {
+                ++r;
+                unsigned char c = unescapechar(r, &r);
+                fputc(c, out);
+                if (c == '\n') ++state->line;
+                continue;
+            } else if (*r == '\n') {
+                fputc('\n', out);
+                ++state->line;
+                ++r;
+                continue;
+            } else {
+                fputc(*r, out);
+                ++r;
+                continue;
+            }
+        }
+    } else {
+        if (m->op->op == VM_CAPTURE) {
+            if (options & PRINT_COLOR && state->color != hl) {
+                state->color = hl;
+                fprintf(out, "%s", state->color);
+            }
+        }
+
+        const char *prev = m->start;
+        for (match_t *child = m->child; child; child = child->nextsibling) {
+            // Skip children from e.g. zero-width matches like >@foo
+            if (!(prev <= child->start && child->start <= m->end &&
+                  prev <= child->end && child->end <= m->end))
+                continue;
+            if (child->start > prev) {
+                for (const char *p = prev; p < child->start; ++p) {
+                    if (state->printed_line != state->line)
+                        print_line_number(out, state, options);
+                    fputc(*p, out);
+                    if (*p == '\n') ++state->line;
+                }
+            }
+            _print_match(out, f, child, state, options);
+            prev = child->end;
+        }
+        if (m->end > prev) {
+            for (const char *p = prev; p < m->end; ++p) {
+                if (state->printed_line != state->line)
+                    print_line_number(out, state, options);
+                fputc(*p, out);
+                if (*p == '\n') ++state->line;
+            }
+        }
+    }
+    if (options & PRINT_COLOR && old_color != state->color) {
+        fprintf(out, "%s", old_color);
+        state->color = old_color;
+    }
+}
+
+void print_match(FILE *out, file_t *f, match_t *m, print_options_t options)
+{
+    print_state_t state = {.line = 1, .color = "\033[0m"};
+    _print_match(out, f, m, &state, options);
+}
+
+// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1