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ferro_cli/commands/
make_theme.rs

1//! make:theme command — scaffold theme files for the Ferro theme system
2//!
3//! Scaffolds plain CSS variable declarations (`:root { ... }`) compatible
4//! with ferro-json-ui's `<style>` injection path.
5
6use console::style;
7use std::fs;
8use std::path::Path;
9
10/// Generate theme scaffold files in `themes/{name}/`.
11///
12/// Creates:
13/// - `themes/{name}/tokens.css` — plain CSS `:root { ... }` block with all 23 semantic token slots
14/// - `themes/{name}/theme.json` — empty JSON object for partial intent template overrides
15///
16/// Returns an error if `themes/{name}/` already exists.
17pub fn make_theme(name: &str) -> Result<(), Box<dyn std::error::Error>> {
18    make_theme_in_dir(name, Path::new("."))
19}
20
21/// Core logic — generate in a given base directory (enables testability).
22pub fn make_theme_in_dir(name: &str, base: &Path) -> Result<(), Box<dyn std::error::Error>> {
23    let theme_dir = base.join("themes").join(name);
24
25    if theme_dir.exists() {
26        return Err(format!("Theme directory '{}' already exists", theme_dir.display()).into());
27    }
28
29    fs::create_dir_all(&theme_dir)?;
30
31    // Write tokens.css — plain CSS variables, injectable into <style> without Tailwind processing
32    let tokens_path = theme_dir.join("tokens.css");
33    fs::write(&tokens_path, tokens_css_template())?;
34
35    // Write theme.json — empty object for partial intent template overrides
36    let theme_json_path = theme_dir.join("theme.json");
37    fs::write(&theme_json_path, "{}\n")?;
38
39    println!(
40        "{} Created theme '{}' at {}/",
41        style("✓").green(),
42        style(name).cyan().bold(),
43        theme_dir.display()
44    );
45    println!();
46    println!("Next steps:");
47    println!(
48        "  {} Edit {}/tokens.css to customize colors, shapes, and typography",
49        style("1.").dim(),
50        theme_dir.display()
51    );
52    println!(
53        "  {} Add intent template overrides to {}/theme.json",
54        style("2.").dim(),
55        theme_dir.display()
56    );
57    println!(
58        "  {} Activate the theme via ThemeMiddleware in your application",
59        style("3.").dim()
60    );
61    println!();
62
63    Ok(())
64}
65
66/// Public entry point called from main.rs.
67pub fn run(name: &str) {
68    if let Err(e) = make_theme(name) {
69        eprintln!("{} {}", style("Error:").red().bold(), e);
70        std::process::exit(1);
71    }
72}
73
74fn tokens_css_template() -> &'static str {
75    r#"/* Theme tokens — plain CSS variables.
76 *
77 * Injected into <style> by ferro-json-ui at render time.
78 * MUST use standard CSS (:root { ... }) — not Tailwind's @theme syntax,
79 * which only works under the Tailwind browser runtime (dev-only).
80 */
81
82:root {
83  /* Surface tokens */
84  --color-background: oklch(100% 0 0);
85  --color-surface: oklch(97% 0 0);
86  --color-card: oklch(95% 0 0);
87  --color-border: oklch(90% 0 0);
88  --color-text: oklch(15% 0 0);
89  --color-text-muted: oklch(50% 0 0);
90
91  /* Role tokens */
92  --color-primary: oklch(55% 0.2 250);
93  --color-primary-foreground: oklch(100% 0 0);
94  --color-secondary: oklch(70% 0.05 250);
95  --color-secondary-foreground: oklch(15% 0 0);
96  --color-accent: oklch(65% 0.15 200);
97  --color-destructive: oklch(55% 0.22 25);
98  --color-success: oklch(55% 0.18 145);
99  --color-warning: oklch(70% 0.18 80);
100
101  /* Shape tokens */
102  --radius-sm: 0.25rem;
103  --radius-md: 0.375rem;
104  --radius-lg: 0.5rem;
105  --radius-full: 9999px;
106
107  /* Shadow tokens */
108  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
109  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
110  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
111
112  /* Typography tokens */
113  --font-sans: "Inter", ui-sans-serif, system-ui, sans-serif;
114  --font-mono: ui-monospace, monospace;
115}
116
117@media (prefers-color-scheme: dark) {
118  :root {
119    --color-background: oklch(12% 0 0);
120    --color-surface: oklch(17% 0 0);
121    --color-card: oklch(20% 0 0);
122    --color-border: oklch(30% 0 0);
123    --color-text: oklch(95% 0 0);
124    --color-text-muted: oklch(60% 0 0);
125    --color-primary: oklch(65% 0.2 250);
126    --color-primary-foreground: oklch(100% 0 0);
127    --color-secondary: oklch(60% 0.05 250);
128    --color-secondary-foreground: oklch(95% 0 0);
129    --color-accent: oklch(60% 0.15 200);
130    --color-destructive: oklch(60% 0.22 25);
131    --color-success: oklch(60% 0.18 145);
132    --color-warning: oklch(65% 0.18 80);
133  }
134}
135"#
136}
137
138#[cfg(test)]
139mod tests {
140    use super::*;
141    use tempfile::TempDir;
142
143    fn read_file(path: &Path) -> String {
144        fs::read_to_string(path).unwrap_or_else(|e| panic!("Failed to read {path:?}: {e}"))
145    }
146
147    #[test]
148    fn test_make_theme_creates_directory_structure() {
149        let tmp = TempDir::new().unwrap();
150        make_theme_in_dir("myapp", tmp.path()).unwrap();
151
152        assert!(tmp.path().join("themes/myapp").exists());
153        assert!(tmp.path().join("themes/myapp/tokens.css").exists());
154        assert!(tmp.path().join("themes/myapp/theme.json").exists());
155    }
156
157    #[test]
158    fn test_make_theme_tokens_css_has_all_23_token_slots() {
159        let tmp = TempDir::new().unwrap();
160        make_theme_in_dir("test", tmp.path()).unwrap();
161
162        let css = read_file(&tmp.path().join("themes/test/tokens.css"));
163
164        // Surface tokens (6)
165        assert!(
166            css.contains("--color-background:"),
167            "missing --color-background"
168        );
169        assert!(css.contains("--color-surface:"), "missing --color-surface");
170        assert!(css.contains("--color-card:"), "missing --color-card");
171        assert!(css.contains("--color-border:"), "missing --color-border");
172        assert!(css.contains("--color-text:"), "missing --color-text");
173        assert!(
174            css.contains("--color-text-muted:"),
175            "missing --color-text-muted"
176        );
177
178        // Role tokens (8)
179        assert!(css.contains("--color-primary:"), "missing --color-primary");
180        assert!(
181            css.contains("--color-primary-foreground:"),
182            "missing --color-primary-foreground"
183        );
184        assert!(
185            css.contains("--color-secondary:"),
186            "missing --color-secondary"
187        );
188        assert!(
189            css.contains("--color-secondary-foreground:"),
190            "missing --color-secondary-foreground"
191        );
192        assert!(css.contains("--color-accent:"), "missing --color-accent");
193        assert!(
194            css.contains("--color-destructive:"),
195            "missing --color-destructive"
196        );
197        assert!(css.contains("--color-success:"), "missing --color-success");
198        assert!(css.contains("--color-warning:"), "missing --color-warning");
199
200        // Shape tokens (4)
201        assert!(css.contains("--radius-sm:"), "missing --radius-sm");
202        assert!(css.contains("--radius-md:"), "missing --radius-md");
203        assert!(css.contains("--radius-lg:"), "missing --radius-lg");
204        assert!(css.contains("--radius-full:"), "missing --radius-full");
205
206        // Shadow tokens (3)
207        assert!(css.contains("--shadow-sm:"), "missing --shadow-sm");
208        assert!(css.contains("--shadow-md:"), "missing --shadow-md");
209        assert!(css.contains("--shadow-lg:"), "missing --shadow-lg");
210
211        // Typography tokens (2)
212        assert!(css.contains("--font-sans:"), "missing --font-sans");
213        assert!(css.contains("--font-mono:"), "missing --font-mono");
214    }
215
216    #[test]
217    fn test_make_theme_tokens_css_has_root_block_and_no_tailwind_syntax() {
218        let tmp = TempDir::new().unwrap();
219        make_theme_in_dir("test", tmp.path()).unwrap();
220
221        let css = read_file(&tmp.path().join("themes/test/tokens.css"));
222
223        // Must NOT contain Tailwind-CDN-only syntax.
224        assert!(
225            !css.contains("@import \"tailwindcss\""),
226            "scaffolded tokens.css must not contain @import \"tailwindcss\" — it is Tailwind-CDN-specific"
227        );
228        assert!(
229            !css.contains("@theme {"),
230            "scaffolded tokens.css must not contain @theme {{...}} — it is Tailwind-CDN-specific"
231        );
232
233        // Must contain plain CSS :root block with the primary token.
234        assert!(css.contains(":root {"), "missing :root {{...}} block");
235        assert!(
236            css.contains("--color-primary:"),
237            "missing --color-primary declaration"
238        );
239    }
240
241    #[test]
242    fn test_make_theme_tokens_css_has_dark_mode_block() {
243        let tmp = TempDir::new().unwrap();
244        make_theme_in_dir("test", tmp.path()).unwrap();
245
246        let css = read_file(&tmp.path().join("themes/test/tokens.css"));
247
248        assert!(
249            css.contains("@media (prefers-color-scheme: dark)"),
250            "missing dark mode @media"
251        );
252        assert!(
253            css.contains("oklch(12%"),
254            "missing dark mode background value"
255        );
256        // Dark mode block must use :root, not @theme { ... }.
257        assert!(
258            !css.contains("@theme {"),
259            "dark-mode block must use :root {{...}}, not @theme {{...}}"
260        );
261    }
262
263    #[test]
264    fn test_make_theme_theme_json_is_empty_object() {
265        let tmp = TempDir::new().unwrap();
266        make_theme_in_dir("test", tmp.path()).unwrap();
267
268        let json_content = read_file(&tmp.path().join("themes/test/theme.json"));
269        let trimmed = json_content.trim();
270
271        // Must be valid JSON that deserializes to an empty object
272        let parsed: serde_json::Value =
273            serde_json::from_str(trimmed).expect("theme.json must be valid JSON");
274        assert_eq!(
275            parsed,
276            serde_json::json!({}),
277            "theme.json must be empty object"
278        );
279    }
280
281    #[test]
282    fn test_make_theme_fails_if_directory_exists() {
283        let tmp = TempDir::new().unwrap();
284
285        // Create the directory first
286        fs::create_dir_all(tmp.path().join("themes/duplicate")).unwrap();
287
288        let result = make_theme_in_dir("duplicate", tmp.path());
289        assert!(
290            result.is_err(),
291            "should return error for duplicate theme name"
292        );
293        let err_msg = result.unwrap_err().to_string();
294        assert!(
295            err_msg.contains("already exists"),
296            "error should mention 'already exists'"
297        );
298    }
299
300    #[test]
301    fn test_make_theme_succeeds_once_fails_on_repeat() {
302        let tmp = TempDir::new().unwrap();
303
304        // First call succeeds
305        make_theme_in_dir("myapp", tmp.path()).unwrap();
306
307        // Second call with same name fails
308        let result = make_theme_in_dir("myapp", tmp.path());
309        assert!(result.is_err());
310    }
311}