c-staticsite-generator/markdown_to_html.c

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

#define BUFFER_SIZE 1024

void convert_markdown_to_html(const char *markdown, FILE *output) {
    const char *start = markdown;
    const char *end;
    bool in_code_block = false;
    bool header_row_started = false;

    while (*start) {
        // Find the end of the current line
        end = strchr(start, '\n');
        if (end == NULL) {
            end = start + strlen(start);
        }

        size_t length = end - start;

        // Ensure we do not exceed the buffer size
        if (length >= BUFFER_SIZE) {
            length = BUFFER_SIZE - 1;
        }

        char line[BUFFER_SIZE];
        strncpy(line, start, length);
        line[length] = '\0';

        // Check for code block delimiters
        if (strcmp(line, "```") == 0) {
            in_code_block = !in_code_block;
            if (in_code_block) {
                fprintf(output, "<pre><code>\n");
            } else {
                fprintf(output, "</code></pre>\n");
            }
        } else if (in_code_block) {
            // If inside a code block, output the line as-is
            fprintf(output, "%s\n", line);
        } else if (line[0] == '|' && strstr(line, "-") != NULL) {
            // Check if it's a header row
            if (!header_row_started) {
                fprintf(output, "<table>\n");
                header_row_started = true;
            }
            fprintf(output, "<tr>\n");
            char *token = strtok(line, "|");
            while (token != NULL) {
                if (strlen(token) > 0) {
                    fprintf(output, "<th style=\"border: 1px solid black;\">%s</th>\n", token);
                }
                token = strtok(NULL, "|");
            }
            fprintf(output, "</tr>\n");
        } else if (header_row_started && (line[0] == '|' || line[0] == '-')) {
            // Regular row
            fprintf(output, "<tr>\n");
            char *token = strtok(line, "|");
            while (token != NULL) {
                if (strlen(token) > 0) {
                    fprintf(output, "<td style=\"border: 1px solid black;\">%s</td>\n", token);
                }
                token = strtok(NULL, "|");
            }
            fprintf(output, "</tr>\n");
        } else {
            // If we were in a table and now we are not, close the table
            if (header_row_started) {
                fprintf(output, "</table>\n");
                header_row_started = false;
            }

            // Handle headers
            if (line[0] == '#') {
                int level = 0;
                while (line[level] == '#') {
                    level++;
                }
                fprintf(output, "<h%d>%s</h%d>\n", level, line + level + 1, level);
            }
            // Handle bold text
            else if (strstr(line, "**") != NULL) {
                char *bold_start = strstr(line, "**");
                char *bold_end = strstr(bold_start + 2, "**");
                if (bold_end != NULL) {
                    *bold_end = '\0';
                    fprintf(output, "%.*s<b>%s</b>%s\n", (int)(bold_start - line), line, bold_start + 2, bold_end + 2);
                }
            }
            // Handle italic text
            else if (strstr(line, "*") != NULL) {
                char *italic_start = strstr(line, "*");
                char *italic_end = strstr(italic_start + 1, "*");
                if (italic_end != NULL) {
                    *italic_end = '\0';
                    fprintf(output, "%.*s<i>%s</i>%s\n", (int)(italic_start - line), line, italic_start + 1, italic_end + 1);
                }
            }
            // Handle list items
            else if (line[0] == '-') {
                fprintf(output, "<li>%s</li>\n", line + 2);
            }
            // Handle links
            else if (strstr(line, "[") != NULL && strstr(line, "](") != NULL) {
                char *link_start = strstr(line, "[");
                char *link_end = strstr(link_start, "]");
                char *url_start = strstr(link_end, "(");
                char *url_end = strstr(url_start, ")");
                if (url_end != NULL) {
                    *link_end = '\0';
                    *url_end = '\0';
                    fprintf(output, "%.*s<a href=\"%s\">%s</a>%s\n", (int)(link_start - line), line, url_start + 1, link_start + 1, url_end + 1);
                }
            }
            // Handle inline code to monospace
            else if (strstr(line, "`") != NULL) {
                char *monospace_start = strstr(line, "`");
                char *monospace_end = strstr(monospace_start + 1, "`");
                if (monospace_end != NULL) {
                    *monospace_end = '\0';
                    fprintf(output, "%.*s<code>%s</code>%s\n", (int)(monospace_start - line), line, monospace_start + 1, monospace_end + 1);
                }
            }
            // Default to paragraph
            else {
                fprintf(output, "<p>%s</p>\n", line);
            }
        }
        start = (*end) ? end + 1 : end;
    }

    // Close any open table at the end
    if (header_row_started) {
        fprintf(output, "</table>\n");
    }
}

/**
 * Generates a static site from a Markdown file.
 *
 * @param input_file The Markdown file to read from.
 * @param output_file The HTML file to write to.
 */
void generate_static_site(const char *input_file, const char *output_file) {
    FILE *md_file = fopen(input_file, "r");
    if (!md_file) {
        perror("Failed to open markdown file");
        return;
    }

    FILE *html_file = fopen(output_file, "w");
    if (!html_file) {
        perror("Failed to create HTML file");
        fclose(md_file);
        return;
    }

    // Write the basic HTML structure with CSS
    fprintf(html_file,
            "<!DOCTYPE html>\n"
            "<html>\n"
            "<head>\n"
            "<title>Static Site</title>\n"
            "<link rel=\"stylesheet\" type=\"text/css\" href=\"styles.css\">\n"
            "</head>\n"
            "<body>\n"
            "<div class=\"container\">\n");

    // Read from markdown file and convert to HTML
    char buffer[BUFFER_SIZE];
    while (fgets(buffer, sizeof(buffer), md_file)) {
        convert_markdown_to_html(buffer, html_file);
    }

    // End container
    fprintf(html_file, "</div>\n</body>\n</html>\n");

    fclose(md_file);
    fclose(html_file);
}

int main(int argc, char *argv[]) {
    if (argc != 3) {
        fprintf(stderr, "Usage: %s <input.md> <output.html>\n", argv[0]);
        return EXIT_FAILURE;
    }

    generate_static_site(argv[1], argv[2]);
    return EXIT_SUCCESS;
}