alef_backend_php/
trait_bridge.rs

1//! PHP (ext-php-rs) specific trait bridge code generation.
2//!
3//! Generates Rust wrapper structs that implement Rust traits by delegating
4//! to PHP objects via ext-php-rs Zval method calls.
5
6use alef_codegen::generators::trait_bridge::{BridgeOutput, TraitBridgeGenerator, TraitBridgeSpec, gen_bridge_all};
7use alef_core::config::TraitBridgeConfig;
8use alef_core::ir::{ApiSurface, MethodDef, TypeDef, TypeRef};
9use std::collections::HashMap;
10use std::fmt::Write;
11
12/// PHP-specific trait bridge generator.
13/// Implements code generation for bridging PHP objects to Rust traits.
14pub struct PhpBridgeGenerator {
15    /// Core crate import path (e.g., `"kreuzberg"`).
16    pub core_import: String,
17    /// Map of type name → fully-qualified Rust path for type references.
18    pub type_paths: HashMap<String, String>,
19    /// Error type name (e.g., `"KreuzbergError"`).
20    pub error_type: String,
21}
22
23impl TraitBridgeGenerator for PhpBridgeGenerator {
24    fn foreign_object_type(&self) -> &str {
25        "&mut ext_php_rs::types::ZendObject"
26    }
27
28    fn bridge_imports(&self) -> Vec<String> {
29        vec!["std::rc::Rc".to_string(), "std::cell::RefCell".to_string()]
30    }
31
32    fn gen_sync_method_body(&self, method: &MethodDef, _spec: &TraitBridgeSpec) -> String {
33        let name = &method.name;
34        let mut out = String::with_capacity(512);
35
36        // PHP is single-threaded; just call the method directly.
37        writeln!(
38            out,
39            "// SAFETY: PHP objects are single-threaded; method calls are safe within a request."
40        )
41        .ok();
42
43        let has_args = !method.params.is_empty();
44        if has_args {
45            writeln!(out, "let mut args: Vec<ext_php_rs::types::Zval> = Vec::new();").ok();
46            for p in &method.params {
47                writeln!(
48                    out,
49                    "args.push(ext_php_rs::types::Zval::try_from({}).unwrap_or_default());",
50                    p.name
51                )
52                .ok();
53            }
54        }
55
56        let args_expr = if has_args {
57            "args.iter().map(|z| z as &dyn ext_php_rs::convert::IntoZvalDyn).collect()"
58        } else {
59            "vec![]"
60        };
61
62        writeln!(out, "let result = self.inner.try_call_method(\"{name}\", {args_expr});").ok();
63        writeln!(out, "match result {{").ok();
64        writeln!(
65            out,
66            "    Ok(val) => val.string().unwrap_or_default().parse().unwrap_or_default(),"
67        )
68        .ok();
69        writeln!(out, "    Err(_) => Default::default(),").ok();
70        writeln!(out, "}}").ok();
71
72        out
73    }
74
75    fn gen_async_method_body(&self, method: &MethodDef, spec: &TraitBridgeSpec) -> String {
76        let name = &method.name;
77        let mut out = String::with_capacity(1024);
78
79        writeln!(out, "let inner_obj = self.inner.clone();").ok();
80        writeln!(out, "let cached_name = self.cached_name.clone();").ok();
81
82        // Clone params for the blocking closure
83        for p in &method.params {
84            match &p.ty {
85                TypeRef::String => {
86                    writeln!(out, "let {} = {}.clone();", p.name, p.name).ok();
87                }
88                _ => {
89                    writeln!(out, "let {} = {};", p.name, p.name).ok();
90                }
91            }
92        }
93
94        writeln!(out).ok();
95        writeln!(out, "Box::pin(async move {{").ok();
96        writeln!(out, "    // SAFETY: PHP objects are single-threaded within a request.").ok();
97        writeln!(out, "    // The block_on executes within the async runtime.").ok();
98        writeln!(out, "    let result = WORKER_RUNTIME.block_on(async {{").ok();
99
100        let has_args = !method.params.is_empty();
101        if has_args {
102            writeln!(out, "        let mut args: Vec<ext_php_rs::types::Zval> = Vec::new();").ok();
103            for p in &method.params {
104                writeln!(
105                    out,
106                    "        args.push(ext_php_rs::types::Zval::try_from({}).unwrap_or_default());",
107                    p.name
108                )
109                .ok();
110            }
111        }
112
113        let args_expr = if has_args {
114            "args.iter().map(|z| z as &dyn ext_php_rs::convert::IntoZvalDyn).collect()"
115        } else {
116            "vec![]"
117        };
118
119        writeln!(
120            out,
121            "        match inner_obj.try_call_method(\"{name}\", {args_expr}) {{"
122        )
123        .ok();
124        writeln!(
125            out,
126            "            Ok(val) => val.string().unwrap_or_default().parse().unwrap_or_default(),"
127        )
128        .ok();
129        writeln!(
130            out,
131            "            Err(e) => Err({}::KreuzbergError::Plugin {{",
132            spec.core_import
133        )
134        .ok();
135        writeln!(
136            out,
137            "                message: format!(\"Plugin '{{}}' method '{name}' failed: {{}}\", cached_name, e),"
138        )
139        .ok();
140        writeln!(out, "                plugin_name: cached_name.clone(),").ok();
141        writeln!(out, "            }}),").ok();
142        writeln!(out, "        }}").ok();
143        writeln!(out, "    }});").ok();
144        writeln!(out, "    result").ok();
145        writeln!(out, "}})").ok();
146
147        out
148    }
149
150    fn gen_constructor(&self, spec: &TraitBridgeSpec) -> String {
151        let wrapper = spec.wrapper_name();
152        let mut out = String::with_capacity(512);
153
154        writeln!(out, "impl {wrapper} {{").ok();
155        writeln!(out, "    /// Create a new bridge wrapping a PHP object.").ok();
156        writeln!(out, "    ///").ok();
157        writeln!(
158            out,
159            "    /// Validates that the PHP object provides all required methods."
160        )
161        .ok();
162        writeln!(
163            out,
164            "    pub fn new(php_obj: &mut ext_php_rs::types::ZendObject) -> Self {{"
165        )
166        .ok();
167
168        // Validate all required methods exist
169        for req_method in spec.required_methods() {
170            writeln!(
171                out,
172                "        debug_assert!(php_obj.get_property(\"{}\").is_some(),",
173                req_method.name
174            )
175            .ok();
176            writeln!(
177                out,
178                "            \"PHP object missing required method: {}\");",
179                req_method.name
180            )
181            .ok();
182        }
183
184        // Extract and cache name
185        writeln!(out, "        let cached_name = php_obj").ok();
186        writeln!(out, "            .try_call_method(\"name\", vec![])").ok();
187        writeln!(out, "            .ok()").ok();
188        writeln!(out, "            .and_then(|v| v.string())").ok();
189        writeln!(out, "            .unwrap_or(\"unknown\".into())").ok();
190        writeln!(out, "            .to_string();").ok();
191
192        writeln!(out).ok();
193        writeln!(out, "        Self {{").ok();
194        writeln!(out, "            inner: php_obj,").ok();
195        writeln!(out, "            cached_name,").ok();
196        writeln!(out, "        }}").ok();
197        writeln!(out, "    }}").ok();
198        writeln!(out, "}}").ok();
199
200        out
201    }
202
203    fn gen_registration_fn(&self, spec: &TraitBridgeSpec) -> String {
204        let Some(register_fn) = spec.bridge_config.register_fn.as_deref() else {
205            return String::new();
206        };
207        let Some(registry_getter) = spec.bridge_config.registry_getter.as_deref() else {
208            return String::new();
209        };
210        let wrapper = spec.wrapper_name();
211        let trait_path = spec.trait_path();
212
213        let mut out = String::with_capacity(1024);
214
215        writeln!(out, "#[php_function]").ok();
216        writeln!(
217            out,
218            "pub fn {register_fn}(backend: &mut ext_php_rs::types::ZendObject) -> ext_php_rs::prelude::PhpResult<()> {{"
219        )
220        .ok();
221
222        // Validate required methods
223        let req_methods: Vec<&MethodDef> = spec.required_methods();
224        if !req_methods.is_empty() {
225            for method in &req_methods {
226                writeln!(out, "    if backend.get_property(\"{}\").is_none() {{", method.name).ok();
227                writeln!(out, "        return Err(ext_php_rs::exception::PhpException::default(").ok();
228                writeln!(
229                    out,
230                    "            format!(\"Backend missing required method: {{}}\", \"{}\")",
231                    method.name
232                )
233                .ok();
234                writeln!(out, "        ).into());").ok();
235                writeln!(out, "    }}").ok();
236            }
237        }
238
239        writeln!(out).ok();
240        writeln!(out, "    let wrapper = {wrapper}::new(backend);").ok();
241        writeln!(
242            out,
243            "    let arc: Rc<RefCell<dyn {trait_path}>> = Rc::new(RefCell::new(wrapper));"
244        )
245        .ok();
246        writeln!(out).ok();
247
248        writeln!(out, "    let registry = {registry_getter}();").ok();
249        writeln!(out, "    let mut registry = registry;").ok();
250        writeln!(
251            out,
252            "    registry.register(arc).map_err(|e| ext_php_rs::exception::PhpException::default("
253        )
254        .ok();
255        writeln!(out, "        format!(\"Failed to register backend: {{}}\", e)").ok();
256        writeln!(out, "    ))?;").ok();
257        writeln!(out, "    Ok(())").ok();
258        writeln!(out, "}}").ok();
259
260        out
261    }
262}
263
264/// Generate all trait bridge code for a given trait type and bridge config.
265pub fn gen_trait_bridge(
266    trait_type: &TypeDef,
267    bridge_cfg: &TraitBridgeConfig,
268    core_import: &str,
269    error_type: &str,
270    api: &ApiSurface,
271) -> BridgeOutput {
272    // Build type name → rust_path lookup as owned HashMap
273    let type_paths: HashMap<String, String> = api
274        .types
275        .iter()
276        .map(|t| (t.name.clone(), t.rust_path.replace('-', "_")))
277        .chain(
278            api.enums
279                .iter()
280                .map(|e| (e.name.clone(), e.rust_path.replace('-', "_"))),
281        )
282        .collect();
283
284    // Visitor-style bridge: all methods have defaults, no registry, no super-trait.
285    let is_visitor_bridge = bridge_cfg.type_alias.is_some()
286        && bridge_cfg.register_fn.is_none()
287        && bridge_cfg.super_trait.is_none()
288        && trait_type.methods.iter().all(|m| m.has_default_impl);
289
290    if is_visitor_bridge {
291        let struct_name = format!("Php{}Bridge", bridge_cfg.trait_name);
292        let trait_path = trait_type.rust_path.replace('-', "_");
293        let code = gen_visitor_bridge(trait_type, bridge_cfg, &struct_name, &trait_path, &type_paths);
294        BridgeOutput { imports: vec![], code }
295    } else {
296        // Use the IR-driven TraitBridgeGenerator infrastructure
297        let generator = PhpBridgeGenerator {
298            core_import: core_import.to_string(),
299            type_paths: type_paths.clone(),
300            error_type: error_type.to_string(),
301        };
302        let spec = TraitBridgeSpec {
303            trait_def: trait_type,
304            bridge_config: bridge_cfg,
305            core_import,
306            wrapper_prefix: "Php",
307            type_paths,
308            error_type: error_type.to_string(),
309        };
310        gen_bridge_all(&spec, &generator)
311    }
312}
313
314/// Generate a visitor-style bridge wrapping a PHP `Zval` object reference.
315///
316/// Every trait method checks if the PHP object has a matching camelCase method,
317/// then calls it and maps the PHP return value to `VisitResult`.
318fn gen_visitor_bridge(
319    trait_type: &TypeDef,
320    _bridge_cfg: &TraitBridgeConfig,
321    struct_name: &str,
322    trait_path: &str,
323    type_paths: &HashMap<String, String>,
324) -> String {
325    let mut out = String::with_capacity(4096);
326    let core_crate = trait_path
327        .split("::")
328        .next()
329        .unwrap_or("html_to_markdown_rs")
330        .to_string();
331    // Helper: convert NodeContext to a PHP array (Zval)
332    writeln!(out, "fn nodecontext_to_php_array(").unwrap();
333    writeln!(out, "    ctx: &{core_crate}::visitor::NodeContext,").unwrap();
334    writeln!(out, ") -> ext_php_rs::boxed::ZBox<ext_php_rs::types::ZendHashTable> {{").unwrap();
335    writeln!(out, "    let mut arr = ext_php_rs::types::ZendHashTable::new();").unwrap();
336    writeln!(
337        out,
338        "    arr.insert(\"nodeType\", ext_php_rs::types::Zval::try_from(format!(\"{{:?}}\", ctx.node_type)).unwrap_or_default()).ok();"
339    )
340    .unwrap();
341    writeln!(
342        out,
343        "    arr.insert(\"tagName\", ext_php_rs::types::Zval::try_from(ctx.tag_name.clone()).unwrap_or_default()).ok();"
344    )
345    .unwrap();
346    writeln!(
347        out,
348        "    arr.insert(\"depth\", ext_php_rs::types::Zval::try_from(ctx.depth as i64).unwrap_or_default()).ok();"
349    )
350    .unwrap();
351    writeln!(
352        out,
353        "    arr.insert(\"indexInParent\", ext_php_rs::types::Zval::try_from(ctx.index_in_parent as i64).unwrap_or_default()).ok();"
354    )
355    .unwrap();
356    writeln!(
357        out,
358        "    arr.insert(\"isInline\", ext_php_rs::types::Zval::try_from(ctx.is_inline).unwrap_or_default()).ok();"
359    )
360    .unwrap();
361    writeln!(out, "    if let Some(ref pt) = ctx.parent_tag {{").unwrap();
362    writeln!(
363        out,
364        "        arr.insert(\"parentTag\", ext_php_rs::types::Zval::try_from(pt.clone()).unwrap_or_default()).ok();"
365    )
366    .unwrap();
367    writeln!(out, "    }}").unwrap();
368    writeln!(out, "    let mut attrs = ext_php_rs::types::ZendHashTable::new();").unwrap();
369    writeln!(out, "    for (k, v) in &ctx.attributes {{").unwrap();
370    writeln!(
371        out,
372        "        attrs.insert(k.as_str(), ext_php_rs::types::Zval::try_from(v.clone()).unwrap_or_default()).ok();"
373    )
374    .unwrap();
375    writeln!(out, "    }}").unwrap();
376    writeln!(out, "    let mut attrs_zval = ext_php_rs::types::Zval::new();").unwrap();
377    writeln!(out, "    attrs_zval.set_hashtable(attrs);").unwrap();
378    writeln!(out, "    arr.insert(\"attributes\", attrs_zval).ok();").unwrap();
379    writeln!(out, "    arr").unwrap();
380    writeln!(out, "}}").unwrap();
381    writeln!(out).unwrap();
382
383    // Bridge struct — stores a reference to the PHP object.
384    // The reference is valid for the duration of the PHP function call that
385    // created the bridge, which spans the entire Rust trait method dispatch.
386    writeln!(out, "pub struct {struct_name} {{").unwrap();
387    writeln!(out, "    php_obj: *mut ext_php_rs::types::ZendObject,").unwrap();
388    writeln!(out, "    cached_name: String,").unwrap();
389    writeln!(out, "}}").unwrap();
390    writeln!(out).unwrap();
391
392    // SAFETY: The raw pointer is only used while the PHP call stack frame is
393    // alive. The bridge is consumed before the PHP function returns.
394    writeln!(out, "// SAFETY: PHP objects are single-threaded; the bridge is used").unwrap();
395    writeln!(out, "// only within a single PHP request, never across threads.").unwrap();
396    writeln!(out, "unsafe impl Send for {struct_name} {{}}").unwrap();
397    writeln!(out, "unsafe impl Sync for {struct_name} {{}}").unwrap();
398    writeln!(out).unwrap();
399
400    writeln!(out, "impl Clone for {struct_name} {{").unwrap();
401    writeln!(out, "    fn clone(&self) -> Self {{").unwrap();
402    writeln!(out, "        Self {{").unwrap();
403    writeln!(out, "            php_obj: self.php_obj,").unwrap();
404    writeln!(out, "            cached_name: self.cached_name.clone(),").unwrap();
405    writeln!(out, "        }}").unwrap();
406    writeln!(out, "    }}").unwrap();
407    writeln!(out, "}}").unwrap();
408    writeln!(out).unwrap();
409
410    // Manual Debug impl
411    writeln!(out, "impl std::fmt::Debug for {struct_name} {{").unwrap();
412    writeln!(
413        out,
414        "    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {{"
415    )
416    .unwrap();
417    writeln!(out, "        write!(f, \"{struct_name}\")").unwrap();
418    writeln!(out, "    }}").unwrap();
419    writeln!(out, "}}").unwrap();
420    writeln!(out).unwrap();
421
422    // Constructor takes &mut ZendObject, which is what ext-php-rs exposes via
423    // FromZvalMut. We store the raw pointer; the caller guarantees the object
424    // outlives this bridge.
425    writeln!(out, "impl {struct_name} {{").unwrap();
426    writeln!(
427        out,
428        "    pub fn new(php_obj: &mut ext_php_rs::types::ZendObject) -> Self {{"
429    )
430    .unwrap();
431    writeln!(out, "        let cached_name = php_obj").unwrap();
432    writeln!(out, "            .try_call_method(\"name\", vec![])").unwrap();
433    writeln!(out, "            .ok()").unwrap();
434    writeln!(out, "            .and_then(|v| v.string())").unwrap();
435    writeln!(out, "            .unwrap_or(\"unknown\".into())").unwrap();
436    writeln!(out, "            .to_string();").unwrap();
437    writeln!(out, "        Self {{ php_obj: php_obj as *mut _, cached_name }}").unwrap();
438    writeln!(out, "    }}").unwrap();
439    writeln!(out, "}}").unwrap();
440    writeln!(out).unwrap();
441
442    // Trait impl
443    writeln!(out, "impl {trait_path} for {struct_name} {{").unwrap();
444    for method in &trait_type.methods {
445        if method.trait_source.is_some() {
446            continue;
447        }
448        gen_visitor_method_php(&mut out, method, type_paths);
449    }
450    writeln!(out, "}}").unwrap();
451    writeln!(out).unwrap();
452
453    out
454}
455
456/// Map a visitor method parameter type to the correct Rust type string.
457fn visitor_param_type(ty: &TypeRef, is_ref: bool, optional: bool, tp: &HashMap<String, String>) -> String {
458    if optional && matches!(ty, TypeRef::String) && is_ref {
459        return "Option<&str>".to_string();
460    }
461    if is_ref {
462        if let TypeRef::Vec(inner) = ty {
463            let inner_str = param_type(inner, "", false, tp);
464            return format!("&[{inner_str}]");
465        }
466    }
467    param_type(ty, "", is_ref, tp)
468}
469
470/// Generate a single visitor method that checks for a camelCase PHP method and calls it.
471fn gen_visitor_method_php(out: &mut String, method: &MethodDef, type_paths: &HashMap<String, String>) {
472    let name = &method.name;
473    let php_name = to_camel_case(name);
474
475    let mut sig_parts = vec!["&mut self".to_string()];
476    for p in &method.params {
477        let ty_str = visitor_param_type(&p.ty, p.is_ref, p.optional, type_paths);
478        sig_parts.push(format!("{}: {}", p.name, ty_str));
479    }
480    let sig = sig_parts.join(", ");
481
482    let ret_ty = match &method.return_type {
483        TypeRef::Named(n) => type_paths.get(n).cloned().unwrap_or_else(|| n.clone()),
484        other => param_type(other, "", false, type_paths),
485    };
486
487    writeln!(out, "    fn {name}({sig}) -> {ret_ty} {{").unwrap();
488
489    // SAFETY: php_obj pointer is valid for the lifetime of the PHP call frame.
490    writeln!(
491        out,
492        "        // SAFETY: php_obj is a valid ZendObject pointer for the duration of this call."
493    )
494    .unwrap();
495    writeln!(out, "        let php_obj_ref = unsafe {{ &mut *self.php_obj }};").unwrap();
496
497    // Build args array
498    let has_args = !method.params.is_empty();
499    if has_args {
500        writeln!(out, "        let mut args: Vec<ext_php_rs::types::Zval> = Vec::new();").unwrap();
501        for p in &method.params {
502            if let TypeRef::Named(n) = &p.ty {
503                if n == "NodeContext" {
504                    writeln!(
505                        out,
506                        "        let ctx_arr = nodecontext_to_php_array({}{});",
507                        if p.is_ref { "" } else { "&" },
508                        p.name
509                    )
510                    .unwrap();
511                    writeln!(
512                        out,
513                        "        args.push(ext_php_rs::convert::IntoZval::into_zval(ctx_arr, false).unwrap_or_default());"
514                    )
515                    .unwrap();
516                    continue;
517                }
518            }
519            // Check optional string ref BEFORE non-optional string, since visitor_param_type
520            // returns Option<&str> for optional string ref params.
521            if p.optional && matches!(&p.ty, TypeRef::String) && p.is_ref {
522                writeln!(
523                    out,
524                    "        args.push(match {0} {{ Some(s) => ext_php_rs::types::Zval::try_from(s.to_string()).unwrap_or_default(), None => ext_php_rs::types::Zval::new() }});",
525                    p.name
526                )
527                .unwrap();
528                continue;
529            }
530            if matches!(&p.ty, TypeRef::String) {
531                if p.is_ref {
532                    writeln!(
533                        out,
534                        "        args.push(ext_php_rs::types::Zval::try_from({}.to_string()).unwrap_or_default());",
535                        p.name
536                    )
537                    .unwrap();
538                } else {
539                    writeln!(
540                        out,
541                        "        args.push(ext_php_rs::types::Zval::try_from({}.clone()).unwrap_or_default());",
542                        p.name
543                    )
544                    .unwrap();
545                }
546                continue;
547            }
548            if matches!(&p.ty, TypeRef::Primitive(alef_core::ir::PrimitiveType::Bool)) {
549                writeln!(
550                    out,
551                    "        {{ let mut _zv = ext_php_rs::types::Zval::new(); _zv.set_bool({}); args.push(_zv); }}",
552                    p.name
553                )
554                .unwrap();
555                continue;
556            }
557            // Default: format as string
558            writeln!(
559                out,
560                "        args.push(ext_php_rs::types::Zval::try_from(format!(\"{{:?}}\", {})).unwrap_or_default());",
561                p.name
562            )
563            .unwrap();
564        }
565    }
566
567    // Call the PHP method via try_call_method which takes Vec<&dyn IntoZvalDyn>.
568    // If the method does not exist, try_call_method returns Err(Error::Callable),
569    // which we treat as a "no-op, return Continue" (same as the default impl).
570    if has_args {
571        writeln!(
572            out,
573            "        let dyn_args: Vec<&dyn ext_php_rs::convert::IntoZvalDyn> = args.iter().map(|z| z as &dyn ext_php_rs::convert::IntoZvalDyn).collect();"
574        )
575        .unwrap();
576    }
577    let args_expr = if has_args { "dyn_args" } else { "vec![]" };
578    writeln!(
579        out,
580        "        let result = php_obj_ref.try_call_method(\"{php_name}\", {args_expr});"
581    )
582    .unwrap();
583
584    // Parse result — try_call_method returns Result<Zval> (not Result<Option<Zval>>)
585    writeln!(out, "        match result {{").unwrap();
586    writeln!(out, "            Err(_) => {ret_ty}::Continue,").unwrap();
587    writeln!(out, "            Ok(val) => {{").unwrap();
588    writeln!(
589        out,
590        "                let s = val.string().unwrap_or_default().to_lowercase();"
591    )
592    .unwrap();
593    writeln!(out, "                match s.as_str() {{").unwrap();
594    writeln!(out, "                    \"continue\" => {ret_ty}::Continue,").unwrap();
595    writeln!(out, "                    \"skip\" => {ret_ty}::Skip,").unwrap();
596    writeln!(
597        out,
598        "                    \"preserve_html\" | \"preservehtml\" => {ret_ty}::PreserveHtml,"
599    )
600    .unwrap();
601    writeln!(out, "                    other => {ret_ty}::Custom(other.to_string()),").unwrap();
602    writeln!(out, "                }}").unwrap();
603    writeln!(out, "            }}").unwrap();
604    writeln!(out, "        }}").unwrap();
605    writeln!(out, "    }}").unwrap();
606    writeln!(out).unwrap();
607}
608
609/// Convert snake_case to camelCase.
610fn to_camel_case(name: &str) -> String {
611    let mut result = String::with_capacity(name.len());
612    let mut capitalize_next = false;
613    for (i, c) in name.chars().enumerate() {
614        if c == '_' {
615            capitalize_next = true;
616        } else if capitalize_next {
617            result.extend(c.to_uppercase());
618            capitalize_next = false;
619        } else if i == 0 {
620            result.extend(c.to_lowercase());
621        } else {
622            result.push(c);
623        }
624    }
625    result
626}
627
628/// Map TypeRef to a Rust type string.
629fn param_type(ty: &TypeRef, ci: &str, is_ref: bool, tp: &HashMap<String, String>) -> String {
630    match ty {
631        TypeRef::Bytes if is_ref => "&[u8]".into(),
632        TypeRef::Bytes => "Vec<u8>".into(),
633        TypeRef::String if is_ref => "&str".into(),
634        TypeRef::String => "String".into(),
635        TypeRef::Path if is_ref => "&std::path::Path".into(),
636        TypeRef::Path => "std::path::PathBuf".into(),
637        TypeRef::Named(n) => {
638            let qualified = tp.get(n).cloned().unwrap_or_else(|| format!("{ci}::{n}"));
639            if is_ref { format!("&{qualified}") } else { qualified }
640        }
641        TypeRef::Vec(inner) => format!("Vec<{}>", param_type(inner, ci, false, tp)),
642        TypeRef::Optional(inner) => format!("Option<{}>", param_type(inner, ci, false, tp)),
643        TypeRef::Primitive(p) => prim(p).into(),
644        TypeRef::Unit => "()".into(),
645        TypeRef::Char => "char".into(),
646        TypeRef::Map(k, v) => format!(
647            "std::collections::HashMap<{}, {}>",
648            param_type(k, ci, false, tp),
649            param_type(v, ci, false, tp)
650        ),
651        TypeRef::Json => "serde_json::Value".into(),
652        TypeRef::Duration => "std::time::Duration".into(),
653    }
654}
655
656fn prim(p: &alef_core::ir::PrimitiveType) -> &'static str {
657    use alef_core::ir::PrimitiveType::*;
658    match p {
659        Bool => "bool",
660        U8 => "u8",
661        U16 => "u16",
662        U32 => "u32",
663        U64 => "u64",
664        I8 => "i8",
665        I16 => "i16",
666        I32 => "i32",
667        I64 => "i64",
668        F32 => "f32",
669        F64 => "f64",
670        Usize => "usize",
671        Isize => "isize",
672    }
673}
674
675/// Find the first parameter index and bridge config where the parameter's named type
676/// matches a trait bridge's `type_alias`.
677///
678/// Returns `None` when no bridge applies.
679pub fn find_bridge_param<'a>(
680    func: &alef_core::ir::FunctionDef,
681    bridges: &'a [TraitBridgeConfig],
682) -> Option<(usize, &'a TraitBridgeConfig)> {
683    for (idx, param) in func.params.iter().enumerate() {
684        let named = match &param.ty {
685            TypeRef::Named(n) => Some(n.as_str()),
686            TypeRef::Optional(inner) => {
687                if let TypeRef::Named(n) = inner.as_ref() {
688                    Some(n.as_str())
689                } else {
690                    None
691                }
692            }
693            _ => None,
694        };
695        for bridge in bridges {
696            if let Some(type_name) = named {
697                if bridge.type_alias.as_deref() == Some(type_name) {
698                    return Some((idx, bridge));
699                }
700            }
701            if bridge.param_name.as_deref() == Some(param.name.as_str()) {
702                return Some((idx, bridge));
703            }
704        }
705    }
706    None
707}
708
709/// Generate a PHP static method that has one parameter replaced by
710/// `Option<ext_php_rs::boxed::ZBox<ext_php_rs::types::ZendObject>>` (a trait bridge).
711#[allow(clippy::too_many_arguments)]
712pub fn gen_bridge_function(
713    func: &alef_core::ir::FunctionDef,
714    bridge_param_idx: usize,
715    bridge_cfg: &TraitBridgeConfig,
716    mapper: &dyn alef_codegen::type_mapper::TypeMapper,
717    opaque_types: &ahash::AHashSet<String>,
718    core_import: &str,
719) -> String {
720    use alef_core::ir::TypeRef;
721
722    let struct_name = format!("Php{}Bridge", bridge_cfg.trait_name);
723    let handle_path = format!("{core_import}::visitor::VisitorHandle");
724    let param_name = &func.params[bridge_param_idx].name;
725    let bridge_param = &func.params[bridge_param_idx];
726    let is_optional = bridge_param.optional || matches!(&bridge_param.ty, TypeRef::Optional(_));
727
728    // Build parameter list, hiding bridge params from signature
729    let mut sig_parts = Vec::new();
730    for (idx, p) in func.params.iter().enumerate() {
731        if idx == bridge_param_idx {
732            // Bridge param: &mut ZendObject implements FromZvalMut in ext-php-rs 0.15,
733            // allowing PHP to pass any object. ZBox<ZendObject> does NOT implement
734            // FromZvalMut, so we must use the reference form here.
735            let php_obj_ty = "&mut ext_php_rs::types::ZendObject";
736            if is_optional {
737                sig_parts.push(format!("{}: Option<{php_obj_ty}>", p.name));
738            } else {
739                sig_parts.push(format!("{}: {php_obj_ty}", p.name));
740            }
741        } else {
742            let promoted = idx > bridge_param_idx || func.params[..idx].iter().any(|pp| pp.optional);
743            let base = mapper.map_type(&p.ty);
744            // #[php_class] types (non-opaque Named) only implement FromZvalMut for &mut T,
745            // not for owned T — so we must use &mut T in the function signature.
746            let ty = match &p.ty {
747                TypeRef::Named(n) if !opaque_types.contains(n.as_str()) => {
748                    if p.optional || promoted {
749                        format!("Option<&mut {base}>")
750                    } else {
751                        format!("&mut {base}")
752                    }
753                }
754                TypeRef::Optional(inner) => {
755                    if let TypeRef::Named(n) = inner.as_ref() {
756                        if !opaque_types.contains(n.as_str()) {
757                            format!("Option<&mut {base}>")
758                        } else if p.optional || promoted {
759                            format!("Option<{base}>")
760                        } else {
761                            base
762                        }
763                    } else if p.optional || promoted {
764                        format!("Option<{base}>")
765                    } else {
766                        base
767                    }
768                }
769                _ => {
770                    if p.optional || promoted {
771                        format!("Option<{base}>")
772                    } else {
773                        base
774                    }
775                }
776            };
777            sig_parts.push(format!("{}: {}", p.name, ty));
778        }
779    }
780
781    let params_str = sig_parts.join(", ");
782    let return_type = mapper.map_type(&func.return_type);
783    let ret = mapper.wrap_return(&return_type, func.error_type.is_some());
784
785    let err_conv = ".map_err(|e| ext_php_rs::exception::PhpException::default(e.to_string()))";
786
787    // Bridge wrapping code
788    let bridge_wrap = if is_optional {
789        format!(
790            "let {param_name} = {param_name}.map(|v| {{\n        \
791             let bridge = {struct_name}::new(v);\n        \
792             std::rc::Rc::new(std::cell::RefCell::new(bridge)) as {handle_path}\n    \
793             }});"
794        )
795    } else {
796        format!(
797            "let {param_name} = {{\n        \
798             let bridge = {struct_name}::new({param_name});\n        \
799             std::rc::Rc::new(std::cell::RefCell::new(bridge)) as {handle_path}\n    \
800             }};"
801        )
802    };
803
804    // Serde let bindings for non-bridge Named params
805    let serde_bindings: String = func
806        .params
807        .iter()
808        .enumerate()
809        .filter(|(idx, p)| {
810            if *idx == bridge_param_idx {
811                return false;
812            }
813            let named = match &p.ty {
814                TypeRef::Named(n) => Some(n.as_str()),
815                TypeRef::Optional(inner) => {
816                    if let TypeRef::Named(n) = inner.as_ref() {
817                        Some(n.as_str())
818                    } else {
819                        None
820                    }
821                }
822                _ => None,
823            };
824            named.is_some_and(|n| !opaque_types.contains(n))
825        })
826        .map(|(_, p)| {
827            let name = &p.name;
828            let core_path = format!(
829                "{core_import}::{}",
830                match &p.ty {
831                    TypeRef::Named(n) => n.clone(),
832                    TypeRef::Optional(inner) =>
833                        if let TypeRef::Named(n) = inner.as_ref() {
834                            n.clone()
835                        } else {
836                            String::new()
837                        },
838                    _ => String::new(),
839                }
840            );
841            if p.optional || matches!(&p.ty, TypeRef::Optional(_)) {
842                format!(
843                    "let {name}_core: Option<{core_path}> = {name}.map(|v| {{\n        \
844                     let json = serde_json::to_string(&v){err_conv}?;\n        \
845                     serde_json::from_str(&json){err_conv}\n    \
846                     }}).transpose()?;\n    "
847                )
848            } else {
849                format!(
850                    "let {name}_json = serde_json::to_string(&{name}){err_conv}?;\n    \
851                     let {name}_core: {core_path} = serde_json::from_str(&{name}_json){err_conv}?;\n    "
852                )
853            }
854        })
855        .collect();
856
857    // Build call args
858    let call_args: Vec<String> = func
859        .params
860        .iter()
861        .enumerate()
862        .map(|(idx, p)| {
863            if idx == bridge_param_idx {
864                return p.name.clone();
865            }
866            match &p.ty {
867                TypeRef::Named(n) if opaque_types.contains(n.as_str()) => {
868                    if p.optional {
869                        format!("{}.as_ref().map(|v| &v.inner)", p.name)
870                    } else {
871                        format!("&{}.inner", p.name)
872                    }
873                }
874                TypeRef::Named(_) => format!("{}_core", p.name),
875                TypeRef::Optional(inner) => {
876                    if let TypeRef::Named(n) = inner.as_ref() {
877                        if opaque_types.contains(n.as_str()) {
878                            format!("{}.as_ref().map(|v| &v.inner)", p.name)
879                        } else {
880                            format!("{}_core", p.name)
881                        }
882                    } else {
883                        p.name.clone()
884                    }
885                }
886                TypeRef::String | TypeRef::Char => {
887                    if p.is_ref {
888                        format!("&{}", p.name)
889                    } else {
890                        p.name.clone()
891                    }
892                }
893                _ => p.name.clone(),
894            }
895        })
896        .collect();
897    let call_args_str = call_args.join(", ");
898
899    let core_fn_path = {
900        let path = func.rust_path.replace('-', "_");
901        if path.starts_with(core_import) {
902            path
903        } else {
904            format!("{core_import}::{}", func.name)
905        }
906    };
907    let core_call = format!("{core_fn_path}({call_args_str})");
908
909    let return_wrap = match &func.return_type {
910        TypeRef::Named(name) if opaque_types.contains(name.as_str()) => {
911            format!("{name} {{ inner: std::sync::Arc::new(val) }}")
912        }
913        TypeRef::Named(_) => "val.into()".to_string(),
914        TypeRef::String | TypeRef::Bytes => "val.into()".to_string(),
915        _ => "val".to_string(),
916    };
917
918    let body = if func.error_type.is_some() {
919        if return_wrap == "val" {
920            format!("{bridge_wrap}\n    {serde_bindings}{core_call}{err_conv}")
921        } else {
922            format!("{bridge_wrap}\n    {serde_bindings}{core_call}.map(|val| {return_wrap}){err_conv}")
923        }
924    } else {
925        format!("{bridge_wrap}\n    {serde_bindings}{core_call}")
926    };
927
928    let func_name = &func.name;
929    let mut out = String::with_capacity(1024);
930    if func.error_type.is_some() {
931        writeln!(out, "#[allow(clippy::missing_errors_doc)]").ok();
932    }
933    writeln!(out, "pub fn {func_name}({params_str}) -> {ret} {{").ok();
934    writeln!(out, "    {body}").ok();
935    writeln!(out, "}}").ok();
936
937    out
938}
alef_backend_php/trait_bridge.rs

alef_backend_php/
trait_bridge.rs
