Dynamic CSS Synthesis and Color Mathematics Implementation. More...

#include <cwist/core/html/css_composer.h>
#include <cwist/core/mem/alloc.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <ctype.h>

Include dependency graph for css_composer.c:

Go to the source code of this file.

Macros
#define	MIN3(a, b, c) ((a) < (b) ? ((a) < (c) ? (a) : (c)) : ((b) < (c) ? (b) : (c)))

#define	MAX3(a, b, c) ((a) > (b) ? ((a) > (c) ? (a) : (c)) : ((b) > (c) ? (b) : (c)))

Functions
cwist_color_hsl	cwist_color_rgb_to_hsl (cwist_color_rgb rgb)
	Convert an RGB color to the HSL color space.

cwist_color_rgb	cwist_color_hsl_to_rgb (cwist_color_hsl hsl)
	Convert an HSL color to the RGB color space.

cwist_color_rgb	cwist_color_hex_to_rgb (const char *hex)
	Parse a hexadecimal color string into an RGB color.

void	cwist_color_rgb_to_hex (cwist_color_rgb rgb, char out_hex[8])
	Format an RGB color as a lowercase "#rrggbb" hex string.

void	cwist_css_config_init (cwist_css_config *cfg)
	Initialize a CSS configuration with default values.

cwist_sstring *	cwist_css_generate_variables (const cwist_css_config *cfg)
	Generate the CSS custom-property block (:root variables) for a config.

cwist_sstring *	cwist_css_generate_utility_classes (const cwist_css_config *cfg)
	Generate the utility/component CSS classes that reference the theme variables.

cwist_sstring *	cwist_css_generate_stylesheet (const cwist_css_config *cfg)
	Generate a complete stylesheet (variables plus utility classes).

void	cwist_css_scope_init (cwist_css_scope scope, const char component_name)
	Initialize a CSS scoping context, deriving a deterministic class suffix.

const char *	cwist_css_scope_class (cwist_css_scope scope, const char base_class)
	Map a base class to its scoped class name, marking it as used.

int	cwist_css_scope_add_rule (cwist_css_scope scope, const char base_class, const char *declarations)
	Attach CSS declarations to a scoped class.

cwist_sstring *	cwist_css_scope_generate_stylesheet (const cwist_css_scope *scope)
	Emit the stylesheet for all used scope entries that have declarations.

void	cwist_css_scope_destroy (cwist_css_scope *scope)
	Destroy a CSS scoping context and free all owned resources.

cwist_sstring *	cwist_css_minify (const char *css)
	Minify CSS source by stripping comments and collapsing whitespace.

cwist_sstring *	cwist_css_bundle (const char const parts, size_t count, bool minify)
	Concatenate CSS parts into one bundle, optionally minified.

Detailed Description

Dynamic CSS Synthesis and Color Mathematics Implementation.

Definition in file css_composer.c.

Macro Definition Documentation

◆ MAX3

#define MAX3	(	a,
		b,
		c
	)	((a) > (b) ? ((a) > (c) ? (a) : (c)) : ((b) > (c) ? (b) : (c)))

Definition at line 16 of file css_composer.c.

◆ MIN3

#define MIN3	(	a,
		b,
		c
	)	((a) < (b) ? ((a) < (c) ? (a) : (c)) : ((b) < (c) ? (b) : (c)))

Definition at line 15 of file css_composer.c.

Function Documentation

◆ cwist_color_hex_to_rgb()

cwist_color_rgb cwist_color_hex_to_rgb ( const char * hex )

Parse a hexadecimal color string into an RGB color.

Parses a hex string (e.g., "#FF0000", "FF0000", "#F00", or "F00") into an RGB struct.

Parameters

hex	Hex string in "#rrggbb", "rrggbb", "#rgb", or "rgb" form. A leading '#' is optional.

Returns: Parsed RGB color. Returns black ({0, 0, 0}) if hex is NULL or malformed (wrong length or non-hex characters).

Definition at line 121 of file css_composer.c.

References cwist_color_rgb::b, cwist_color_rgb::g, and cwist_color_rgb::r.

Referenced by cwist_css_config_init().

◆ cwist_color_hsl_to_rgb()

cwist_color_rgb cwist_color_hsl_to_rgb ( cwist_color_hsl hsl )

Convert an HSL color to the RGB color space.

Converts an HSL color back to RGB color space.

Parameters

hsl	Hue in degrees (0-360), saturation and lightness in 0-1.

Returns: RGB components in the range 0-255, rounded to the nearest integer. A saturation of 0 yields a grayscale color.

Definition at line 76 of file css_composer.c.

References cwist_color_rgb::b, cwist_color_rgb::g, cwist_color_hsl::h, cwist_color_hsl::l, cwist_color_rgb::r, and cwist_color_hsl::s.

◆ cwist_color_rgb_to_hex()

void cwist_color_rgb_to_hex	(	cwist_color_rgb	rgb,
		char	out_hex[8]
	)

Format an RGB color as a lowercase "#rrggbb" hex string.

Formats an RGB struct into a 7-character hex string (e.g., "#FFFFFF").

Parameters

rgb	RGB components in the range 0-255.
out_hex	Output buffer of at least 8 bytes; left untouched if NULL.

Definition at line 156 of file css_composer.c.

References cwist_color_rgb::b, cwist_color_rgb::g, and cwist_color_rgb::r.

Referenced by cwist_css_generate_variables().

◆ cwist_color_rgb_to_hsl()

cwist_color_hsl cwist_color_rgb_to_hsl ( cwist_color_rgb rgb )

Convert an RGB color to the HSL color space.

Converts an RGB color to HSL color space.

Parameters

rgb	RGB components in the range 0-255.

Returns: HSL with hue in degrees (0-360), saturation and lightness in 0-1. Achromatic colors yield saturation and hue of 0.

Definition at line 24 of file css_composer.c.

References cwist_color_rgb::b, cwist_color_rgb::g, cwist_color_hsl::h, cwist_color_hsl::l, MAX3, MIN3, cwist_color_rgb::r, and cwist_color_hsl::s.

◆ cwist_css_bundle()

cwist_sstring * cwist_css_bundle	(	const char const	parts,
		size_t	count,
		bool	minify
	)

Concatenate CSS parts into one bundle, optionally minified.

Concatenate stylesheets in order into one bundle, optionally minified.

Parameters

parts	Array of CSS text fragments; may be NULL only if `count` is 0.
count	Number of entries in `parts`.
minify	If true, the concatenated result is passed through cwist_css_minify().

Returns: Newly created sstring with the bundled CSS, or NULL on invalid input or allocation failure. Caller owns the returned string.

Definition at line 654 of file css_composer.c.

References count, cwist_css_minify(), cwist_error_dispose(), cwist_sstring_assign(), cwist_sstring_create(), cwist_sstring_destroy(), and cwist_sstring::data.

◆ cwist_css_config_init()

void cwist_css_config_init ( cwist_css_config * cfg )

Initialize a CSS configuration with default values.

Initializes a CSS configuration with sensible defaults.

Parameters

cfg	Configuration to fill. No-op if NULL.

Defaults: Tailwind blue primary, Tailwind green secondary, 8px roundness, 4px spacing base, light mode.

Definition at line 168 of file css_composer.c.

References cwist_color_hex_to_rgb(), cwist_css_config::is_dark_mode, cwist_css_config::primary_color, cwist_css_config::roundness_px, cwist_css_config::secondary_color, and cwist_css_config::spacing_base_px.

◆ cwist_css_generate_stylesheet()

cwist_sstring * cwist_css_generate_stylesheet ( const cwist_css_config * cfg )

Generate a complete stylesheet (variables plus utility classes).

High-level helper to generate a complete stylesheet (Variables + Utilities).

Parameters

cfg	Theme configuration; must not be NULL.

Returns: Newly created sstring with the concatenated CSS, or NULL if cfg is NULL or allocation fails. Caller owns the returned string.

Definition at line 294 of file css_composer.c.

References cwist_css_generate_utility_classes(), cwist_css_generate_variables(), cwist_sstring_append(), cwist_sstring_create(), cwist_sstring_destroy(), and cwist_sstring::data.

◆ cwist_css_generate_utility_classes()

cwist_sstring * cwist_css_generate_utility_classes ( const cwist_css_config * cfg )

Generate the utility/component CSS classes that reference the theme variables.

Generates a set of utility classes based on the design system configuration.

Parameters

cfg	Theme configuration (currently unused; classes reference CSS variables).

Returns: Newly created sstring with the generated CSS, or NULL on allocation failure. Caller owns the returned string.

Definition at line 248 of file css_composer.c.

References cwist_sstring_append(), and cwist_sstring_create().

Referenced by cwist_css_generate_stylesheet().

◆ cwist_css_generate_variables()

cwist_sstring * cwist_css_generate_variables ( const cwist_css_config * cfg )

Generate the CSS custom-property block (:root variables) for a config.

Generates a CSS string containing CSS Custom Properties (:root variables). Extrapolates hover states, active states, and surface colors mathematically.

Parameters

cfg	Theme configuration; must not be NULL.

Returns: Newly created sstring with the generated CSS, or NULL if cfg is NULL or allocation fails. Caller owns the returned string.

Definition at line 195 of file css_composer.c.

References cwist_color_rgb_to_hex(), cwist_sstring_append(), cwist_sstring_create(), cwist_css_config::is_dark_mode, cwist_css_config::primary_color, cwist_css_config::roundness_px, cwist_css_config::secondary_color, and cwist_css_config::spacing_base_px.

Referenced by cwist_css_generate_stylesheet().

◆ cwist_css_minify()

cwist_sstring * cwist_css_minify ( const char * css )

Minify CSS source by stripping comments and collapsing whitespace.

Minify a stylesheet without changing what it means.

Parameters

css	CSS source text; must not be NULL.

Returns: Newly created sstring with the minified CSS, or NULL on invalid input or allocation failure. Caller owns the returned string.

Preserves license comments (those opening with a '!'), quoted strings, escapes, and unquoted url() arguments verbatim. Whitespace around structural characters and comments is dropped unless removing it would glue two tokens.

Definition at line 547 of file css_composer.c.

References cwist_alloc(), cwist_error_dispose(), cwist_free(), cwist_sstring_assign_len(), cwist_sstring_create(), and cwist_sstring_destroy().

Referenced by cwist_css_bundle().

◆ cwist_css_scope_add_rule()

int cwist_css_scope_add_rule	(	cwist_css_scope *	scope,
		const char *	base_class,
		const char *	declarations
	)

Attach CSS declarations to a scoped class.

Attach declarations to a base class, replacing any earlier ones.

Parameters

scope	Scope to modify.
base_class	Base class name; must be a valid CSS identifier.
declarations	Declaration block text (e.g. "color: red;"). Must not contain '{', '}', or '<'.

Return values

0	Declarations stored; any previous declarations are freed.
-1	Invalid argument, unsafe declaration content, or allocation failure.

Definition at line 444 of file css_composer.c.

References cwist_free(), cwist_strdup(), and cwist_css_scope::suffix.

◆ cwist_css_scope_class()

const char * cwist_css_scope_class	(	cwist_css_scope *	scope,
		const char *	base_class
	)

Map a base class to its scoped class name, marking it as used.

Map a base class to its scoped name ("btn" -> "btn-a1b2c3d4").

Parameters

scope	Scope to query.
base_class	Base class name; must be a valid CSS identifier.

Returns: Pointer to the scoped class name (e.g. "btn-a1b2c3d4") owned by the scope entry, or NULL on invalid input or allocation failure.

Definition at line 427 of file css_composer.c.

References cwist_css_scope::suffix.

◆ cwist_css_scope_destroy()

void cwist_css_scope_destroy ( cwist_css_scope * scope )

Destroy a CSS scoping context and free all owned resources.

Release everything the scope owns and reset it to an empty state.

Parameters

scope Scope to tear down. No-op if NULL.

Frees all entry base names, scoped class strings, and declaration copies, then zeroes the scope struct.

Definition at line 496 of file css_composer.c.

References cwist_css_scope::count, cwist_free(), cwist_sstring_destroy(), and cwist_css_scope::entries.

◆ cwist_css_scope_generate_stylesheet()

cwist_sstring * cwist_css_scope_generate_stylesheet ( const cwist_css_scope * scope )

Emit the stylesheet for all used scope entries that have declarations.

Emit one rule per class that is both used and has declarations.

Parameters

scope Scope to render; must not be NULL.

Returns: Newly created sstring with one ".<scoped-class> { ... }" rule per used entry, or NULL if scope is NULL or allocation fails. Caller owns the returned string.

Definition at line 468 of file css_composer.c.

References cwist_css_scope::count, cwist_error_dispose(), cwist_sstring_assign(), cwist_sstring_create(), cwist_sstring_destroy(), and cwist_css_scope::entries.

◆ cwist_css_scope_init()

void cwist_css_scope_init	(	cwist_css_scope *	scope,
		const char *	component_name
	)

Initialize a CSS scoping context, deriving a deterministic class suffix.

Initialise a scope for one component.

Parameters

scope	Scope to initialize. No-op if NULL.
component_name	Name used to derive the suffix; empty string if NULL.

The suffix is an unseeded FNV-1a 32-bit hash of the component name, so markup and stylesheets generated in different worker processes agree on the same suffix. Call cwist_css_scope_destroy() to release.

Definition at line 402 of file css_composer.c.

References cwist_css_scope::capacity, cwist_css_scope::count, cwist_css_scope::entries, and cwist_css_scope::suffix.

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ MAX3

◆ MIN3

Function Documentation

◆ cwist_color_hex_to_rgb()

◆ cwist_color_hsl_to_rgb()

◆ cwist_color_rgb_to_hex()

◆ cwist_color_rgb_to_hsl()

◆ cwist_css_bundle()

◆ cwist_css_config_init()

◆ cwist_css_generate_stylesheet()

◆ cwist_css_generate_utility_classes()

◆ cwist_css_generate_variables()

◆ cwist_css_minify()

◆ cwist_css_scope_add_rule()

◆ cwist_css_scope_class()

◆ cwist_css_scope_destroy()

◆ cwist_css_scope_generate_stylesheet()

◆ cwist_css_scope_init()