src/kernel --> src/

src/userland/gui/markdown.c

@@ -0,0 +1,450 @@
+// Copyright (c) 2023-2026 Chris (boreddevnl)
+// This software is released under the GNU General Public License v3.0. See LICENSE file for details.
+// This header needs to maintain in any file it is present in, as per the GPL license terms.
+#include "libc/syscall.h"
+#include "libc/libui.h"
+#include "libc/stdlib.h"
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+
+#define MD_MAX_CONTENT 16384
+#define MD_MAX_LINES 256
+#define MD_CHAR_WIDTH 8
+#define MD_LINE_HEIGHT 16
+
+#define COLOR_DARK_PANEL    0xFF202020
+#define COLOR_DARK_BG       0xFF121212
+#define COLOR_DARK_TEXT     0xFFE0E0E0
+#define COLOR_DARK_TITLEBAR 0xFF303030
+#define COLOR_BLACK         0xFF000000
+
+typedef enum {
+    MD_LINE_NORMAL,
+    MD_LINE_HEADING1,
+    MD_LINE_HEADING2,
+    MD_LINE_HEADING3,
+    MD_LINE_BOLD,
+    MD_LINE_ITALIC,
+    MD_LINE_LIST,
+    MD_LINE_BLOCKQUOTE,
+    MD_LINE_CODE
+} MDLineType;
+
+typedef struct {
+    char content[256];
+    int length;
+    MDLineType type;
+    int indent_level;
+} MDLine;
+
+static MDLine lines[MD_MAX_LINES];
+static int line_count = 0;
+static int scroll_top = 0;
+static char open_filename[256] = "";
+
+static int win_w = 600;
+static int win_h = 400;
+
+static size_t md_strlen(const char *str) {
+    size_t len = 0;
+    while (str[len]) len++;
+    return len;
+}
+
+static void md_strcpy(char *dest, const char *src) {
+    while (*src) *dest++ = *src++;
+    *dest = 0;
+}
+
+static int md_strncpy(char *dest, const char *src, int n) {
+    int i = 0;
+    while (i < n && src[i]) {
+        dest[i] = src[i];
+        i++;
+    }
+    dest[i] = 0;
+    return i;
+}
+
+static void md_parse_line(const char *raw_line, char *output, MDLineType *type, int *indent) {
+    int i = 0;
+    int out_idx = 0;
+    *indent = 0;
+    *type = MD_LINE_NORMAL;
+    
+    while (raw_line[i] == ' ' || raw_line[i] == '\t') {
+        if (raw_line[i] == '\t') *indent += 2;
+        else *indent += 1;
+        i++;
+    }
+    
+    if (raw_line[i] == '#') {
+        int hash_count = 0;
+        while (raw_line[i] == '#') {
+            hash_count++;
+            i++;
+        }
+        if (raw_line[i] == ' ') i++;
+        
+        if (hash_count == 1) *type = MD_LINE_HEADING1;
+        else if (hash_count == 2) *type = MD_LINE_HEADING2;
+        else if (hash_count <= 6) *type = MD_LINE_HEADING3;
+    } else if (raw_line[i] == '-' || raw_line[i] == '*') {
+        if ((raw_line[i] == '-' || raw_line[i] == '*') && (raw_line[i+1] == ' ' || raw_line[i+1] == '\t')) {
+            *type = MD_LINE_LIST;
+            i += 2;
+            while (raw_line[i] == ' ' || raw_line[i] == '\t') i++;
+        }
+    } else if (raw_line[i] == '>') {
+        *type = MD_LINE_BLOCKQUOTE;
+        i++;
+        if (raw_line[i] == ' ') i++;
+    }
+    
+    while (raw_line[i] && out_idx < 255) {
+        if (raw_line[i] == '*' && raw_line[i+1] == '*') {
+            i += 2;
+            while (raw_line[i] && !(raw_line[i] == '*' && raw_line[i+1] == '*') && out_idx < 255) {
+                output[out_idx++] = raw_line[i++];
+            }
+            if (raw_line[i] == '*' && raw_line[i+1] == '*') i += 2;
+            continue;
+        }
+        if ((raw_line[i] == '*' || raw_line[i] == '_') && out_idx > 0 && raw_line[i-1] != '\\') {
+            char delim = raw_line[i];
+            i++;
+            while (raw_line[i] && raw_line[i] != delim && out_idx < 255) {
+                output[out_idx++] = raw_line[i++];
+            }
+            if (raw_line[i] == delim) i++;
+            continue;
+        }
+        if (raw_line[i] == '`') {
+            i++;
+            while (raw_line[i] && raw_line[i] != '`' && out_idx < 255) {
+                output[out_idx++] = raw_line[i++];
+            }
+            if (raw_line[i] == '`') i++;
+            continue;
+        }
+        if (raw_line[i] == '[') {
+            i++;
+            while (raw_line[i] && raw_line[i] != ']' && out_idx < 255) {
+                output[out_idx++] = raw_line[i++];
+            }
+            if (raw_line[i] == ']') i++;
+            if (raw_line[i] == '(') {
+                while (raw_line[i] && raw_line[i] != ')') i++;
+                if (raw_line[i] == ')') i++;
+            }
+            continue;
+        }
+        output[out_idx++] = raw_line[i++];
+    }
+    output[out_idx] = 0;
+}
+
+static void md_clear_all(void) {
+    for (int i = 0; i < MD_MAX_LINES; i++) {
+        lines[i].content[0] = 0;
+        lines[i].length = 0;
+        lines[i].type = MD_LINE_NORMAL;
+        lines[i].indent_level = 0;
+    }
+    line_count = 0;
+    scroll_top = 0;
+    open_filename[0] = 0;
+}
+
+void markdown_open_file(const char *filename) {
+    md_clear_all();
+    md_strcpy(open_filename, filename);
+    
+    int fd = sys_open(filename, "r");
+    if (fd < 0) return;
+    
+    static char buffer[MD_MAX_CONTENT];
+    int bytes_read = sys_read(fd, buffer, sizeof(buffer) - 1);
+    sys_close(fd);
+    
+    if (bytes_read <= 0) return;
+    buffer[bytes_read] = 0;
+    
+    int line = 0;
+    int col = 0;
+    char raw_line[256] = "";
+    bool in_code_block = false;
+    
+    for (int i = 0; i < bytes_read && line < MD_MAX_LINES; i++) {
+        char ch = buffer[i];
+        if (ch == '\n') {
+            raw_line[col] = 0;
+            if (raw_line[0] == '`' && raw_line[1] == '`' && raw_line[2] == '`') {
+                in_code_block = !in_code_block;
+            } else {
+                if (in_code_block) {
+                    md_strcpy(lines[line].content, raw_line);
+                    lines[line].length = md_strlen(raw_line);
+                    lines[line].type = MD_LINE_CODE;
+                    lines[line].indent_level = 0;
+                    line++;
+                } else {
+                    char parsed_content[256];
+                    MDLineType type;
+                    int indent;
+                    md_parse_line(raw_line, parsed_content, &type, &indent);
+                    md_strcpy(lines[line].content, parsed_content);
+                    lines[line].length = md_strlen(parsed_content);
+                    lines[line].type = type;
+                    lines[line].indent_level = indent;
+                    line++;
+                }
+            }
+            col = 0;
+            raw_line[0] = 0;
+        } else if (col < 255) {
+            raw_line[col++] = ch;
+        }
+    }
+    
+    if (col > 0 && line < MD_MAX_LINES) {
+        raw_line[col] = 0;
+        if (raw_line[0] == '`' && raw_line[1] == '`' && raw_line[2] == '`') {
+        } else if (in_code_block) {
+            md_strcpy(lines[line].content, raw_line);
+            lines[line].length = md_strlen(raw_line);
+            lines[line].type = MD_LINE_CODE;
+            lines[line].indent_level = 0;
+            line++;
+        } else {
+            char parsed_content[256];
+            MDLineType type;
+            int indent;
+            md_parse_line(raw_line, parsed_content, &type, &indent);
+            md_strcpy(lines[line].content, parsed_content);
+            lines[line].length = md_strlen(parsed_content);
+            lines[line].type = type;
+            lines[line].indent_level = indent;
+            line++;
+        }
+    }
+    line_count = line;
+}
+
+static void md_draw_text_bold(ui_window_t win, int x, int y, const char *text, uint32_t color) {
+    ui_draw_string(win, x, y, text, color);
+    ui_draw_string(win, x + 1, y, text, color);
+}
+
+static void md_paint(ui_window_t win) {
+    int offset_x = 4;
+    int offset_y = 0;
+    int content_width = win_w - 8;
+    int content_height = win_h - 28;
+    
+    ui_draw_rounded_rect_filled(win, offset_x, offset_y, content_width, 20, 6, COLOR_DARK_PANEL);
+    ui_draw_string(win, offset_x + 4, offset_y + 4, "File", COLOR_DARK_TEXT);
+    ui_draw_string(win, offset_x + 50, offset_y + 4, open_filename, COLOR_DARK_TEXT);
+    
+    int btn_x_up = offset_x + content_width - 50;
+    int btn_y = offset_y + 2;
+    ui_draw_rounded_rect_filled(win, btn_x_up, btn_y, 20, 16, 4, COLOR_DARK_TITLEBAR);
+    ui_draw_string(win, btn_x_up + 6, btn_y, "^", COLOR_DARK_TEXT);
+    ui_draw_rounded_rect_filled(win, btn_x_up + 24, btn_y, 20, 16, 4, COLOR_DARK_TITLEBAR);
+    ui_draw_string(win, btn_x_up + 30, btn_y, "v", COLOR_DARK_TEXT);
+    
+    int content_start_y = offset_y + 24;
+    int content_start_x = offset_x + 4;
+    int usable_content_width = content_width - 8 - 20;
+    int usable_content_height = content_height - 28;
+    int max_display_lines = usable_content_height / MD_LINE_HEIGHT;
+    
+    ui_draw_rounded_rect_filled(win, 4, content_start_y, win_w - 24, usable_content_height, 6, COLOR_DARK_BG);
+    
+    int display_line = 0;
+    int i = scroll_top;
+    
+    while (i < line_count && display_line < max_display_lines) {
+        MDLine *line = &lines[i];
+        
+        int line_height = MD_LINE_HEIGHT;
+        int extra_spacing = 0;
+        uint32_t text_color = COLOR_DARK_TEXT;
+        bool use_bold = false;
+        
+        switch (line->type) {
+            case MD_LINE_HEADING1:
+                line_height = MD_LINE_HEIGHT * 2;
+                text_color = 0xFF87CEEB;
+                use_bold = true;
+                extra_spacing = 4;
+                break;
+            case MD_LINE_HEADING2:
+                line_height = MD_LINE_HEIGHT + 6;
+                text_color = 0xFF4A90E2;
+                use_bold = true;
+                extra_spacing = 2;
+                break;
+            case MD_LINE_HEADING3:
+                line_height = MD_LINE_HEIGHT + 2;
+                text_color = 0xFF87CEEB;
+                use_bold = false;
+                break;
+            case MD_LINE_BLOCKQUOTE:
+                text_color = 0xFFA0A0A0;
+                break;
+            case MD_LINE_CODE:
+                text_color = 0xFF90EE90;
+                break;
+            default:
+                text_color = COLOR_DARK_TEXT;
+                break;
+        }
+        
+        if (display_line + (line_height / MD_LINE_HEIGHT) > max_display_lines) break;
+        
+        int x_offset = content_start_x + (line->indent_level * 4);
+        int available_width = usable_content_width - (line->indent_level * 4);
+        int max_chars_per_line = available_width / MD_CHAR_WIDTH;
+        if (max_chars_per_line < 1) max_chars_per_line = 1;
+        
+        const char *text = line->content;
+        int text_len = line->length;
+        int char_idx = 0;
+        int local_display_line = 0;
+        int wrapped_line_count = 0;
+        
+        while (char_idx < text_len || (text_len == 0 && local_display_line == 0)) {
+            int line_y = content_start_y + display_line * MD_LINE_HEIGHT + (local_display_line * MD_LINE_HEIGHT);
+            
+            char line_segment[256];
+            int segment_len = 0;
+            int segment_start = char_idx;
+            
+            while (char_idx < text_len && segment_len < max_chars_per_line) {
+                line_segment[segment_len++] = text[char_idx++];
+            }
+            line_segment[segment_len] = 0;
+            
+            if (char_idx < text_len && segment_len > 0) {
+                int last_space = -1;
+                for (int j = segment_len - 1; j >= 0; j--) {
+                    if (line_segment[j] == ' ') {
+                        last_space = j; break;
+                    }
+                }
+                if (last_space > 0) {
+                    segment_len = last_space;
+                    line_segment[segment_len] = 0;
+                    char_idx = segment_start + last_space + 1;
+                    while (char_idx < text_len && text[char_idx] == ' ') char_idx++;
+                }
+            }
+            
+            if (line->type == MD_LINE_CODE && segment_len > 0) {
+                ui_draw_rect(win, x_offset - 2, line_y - 2, (segment_len * MD_CHAR_WIDTH) + 4, 12, COLOR_BLACK);
+            }
+
+            if (local_display_line == 0) {
+                switch (line->type) {
+                    case MD_LINE_LIST:
+                        ui_draw_rect(win, x_offset, line_y + MD_LINE_HEIGHT/2 - 1, 2, 2, COLOR_BLACK);
+                        x_offset += 12;
+                        if (segment_len > 0 && line_segment[0] == ' ') {
+                            for (int j = 0; j < segment_len - 1; j++) line_segment[j] = line_segment[j + 1];
+                            segment_len--;
+                        }
+                        break;
+                    case MD_LINE_BLOCKQUOTE:
+                        ui_draw_rect(win, x_offset - 4, line_y, 2, line_height, 0xFF404080);
+                        break;
+                    default: break;
+                }
+            }
+            
+            if (segment_len > 0) {
+                if (use_bold) {
+                    md_draw_text_bold(win, x_offset, line_y + extra_spacing, line_segment, text_color);
+                } else {
+                    ui_draw_string(win, x_offset, line_y, line_segment, text_color);
+                }
+            }
+            
+            local_display_line++;
+            wrapped_line_count++;
+            if (char_idx >= text_len) break;
+        }
+        
+        display_line += (wrapped_line_count > 0 ? wrapped_line_count : 1);
+        i++;
+    }
+}
+
+static void md_handle_key(char c, bool pressed) {
+    if (!pressed) return;
+    if (c == 'w' || c == 'W' || c == 17) {
+        scroll_top -= 3;
+        if (scroll_top < 0) scroll_top = 0;
+    } else if (c == 's' || c == 'S' || c == 18) {
+        scroll_top += 3;
+        int max_scroll = line_count - 10;
+        if (scroll_top > max_scroll) scroll_top = max_scroll;
+        if (scroll_top < 0) scroll_top = 0;
+    }
+}
+
+static void md_handle_click(int x, int y) {
+    int content_width = win_w - 8;
+    int btn_x_up = 4 + content_width - 50;
+    int btn_y = 2;
+    if (x >= btn_x_up && x < btn_x_up + 20 && y >= btn_y && y < btn_y + 16) {
+        scroll_top -= 3;
+        if (scroll_top < 0) scroll_top = 0;
+        return;
+    }
+    
+    int btn_x_down_top = 4 + content_width - 50 + 24;
+    if (x >= btn_x_down_top && x < btn_x_down_top + 20 && y >= btn_y && y < btn_y + 16) {
+        scroll_top += 3;
+        int max_scroll = line_count - 10;
+        if (scroll_top > max_scroll) scroll_top = max_scroll;
+        if (scroll_top < 0) scroll_top = 0;
+        return;
+    }
+}
+
+int main(int argc, char **argv) {
+    ui_window_t win = ui_window_create("Markdown Viewer", 150, 180, win_w, win_h);
+    if (!win) return 1;
+
+    md_clear_all();
+    if (argc > 1) {
+        markdown_open_file(argv[1]);
+    }
+
+    gui_event_t ev;
+    while (1) {
+        if (ui_get_event(win, &ev)) {
+            if (ev.type == GUI_EVENT_PAINT) {
+                md_paint(win);
+                ui_mark_dirty(win, 0, 0, win_w, win_h - 20);
+            } else if (ev.type == GUI_EVENT_CLICK) {
+                md_handle_click(ev.arg1, ev.arg2);
+                md_paint(win);
+                ui_mark_dirty(win, 0, 0, win_w, win_h - 20);
+            } else if (ev.type == GUI_EVENT_KEY) {
+                md_handle_key((char)ev.arg1, true);
+                md_paint(win);
+                ui_mark_dirty(win, 0, 0, win_w, win_h - 20);
+            } else if (ev.type == GUI_EVENT_KEYUP) {
+                md_handle_key((char)ev.arg1, false);
+            } else if (ev.type == GUI_EVENT_CLOSE) {
+                sys_exit(0);
+            }
+        } else {
+            sleep(10);
+        }
+    }
+    return 0;
+}