Initial commit of document-service

app/pdf.py

@@ -0,0 +1,105 @@
+import os
+from pypdf import PdfReader
+from typing import Any
+
+def discover_fields(pdf_path: str) -> list[dict]:
+    """
+    Introspect a PDF and return all fillable AcroForm fields.
+    Handles any form of AcroForm structure.
+    """
+    reader = PdfReader(pdf_path)
+    
+    # Try multiple methods to get fields
+    fields = None
+    
+    # Method 1: Try get_fields() first
+    try:
+        fields = reader.get_fields()
+    except Exception as e:
+        print(f"get_fields() failed: {e}")
+        fields = None
+    
+    # Method 2: Try to get fields from AcroForm directly
+    if not fields:
+        try:
+            if "/AcroForm" in reader.trailer["/Root"]:
+                acroform = reader.trailer["/Root"]["/AcroForm"]
+                if "/Fields" in acroform:
+                    fields = {}
+                    field_array = acroform["/Fields"]
+                    for field_ref in field_array:
+                        try:
+                            field_obj = field_ref.get_object()
+                            field_name = field_obj.get("/T", "")
+                            if field_name:
+                                fields[field_name] = field_obj
+                        except Exception as e:
+                            print(f"Error processing field: {e}")
+                            continue
+        except Exception as e:
+            print(f"Direct AcroForm access failed: {e}")
+            fields = None
+    
+    # Method 3: Try to get fields from page annotations
+    if not fields:
+        try:
+            fields = {}
+            for page in reader.pages:
+                if "/Annots" in page:
+                    for annot in page["/Annots"]:
+                        try:
+                            annot_obj = annot.get_object()
+                            if "/Subtype" in annot_obj and annot_obj["/Subtype"] == "/Widget":
+                                field_name = annot_obj.get("/T", "")
+                                if field_name and field_name not in fields:
+                                    fields[field_name] = annot_obj
+                        except Exception as e:
+                            print(f"Error processing annotation: {e}")
+                            continue
+        except Exception as e:
+            print(f"Page annotation access failed: {e}")
+            fields = None
+
+    if not fields:
+        return []
+
+    result = []
+    for field_name, field_obj in fields.items():
+        try:
+            field_type = field_obj.get("/FT", "")
+            options = []
+
+            # /Ch = choice field (select/dropdown)
+            if field_type == "/Ch":
+                opt = field_obj.get("/Opt", [])
+                if opt:
+                    options = [o if isinstance(o, str) else o[1] for o in opt]
+
+            result.append({
+                "field": field_name,
+                "label": field_name.replace("_", " ").title(),
+                "type": _map_field_type(field_type, field_obj),
+                "required": False,
+                "options": options if options else None
+            })
+        except Exception as e:
+            print(f"Error processing field {field_name}: {e}")
+            continue
+
+    return result
+
+def _map_field_type(ft: str, field_obj: dict) -> str:
+    mapping = {
+        "/Tx": "string",
+        "/Btn": "boolean",
+        "/Ch": "select",
+        "/Sig": "string"
+    }
+    base = mapping.get(ft, "string")
+
+    # Check if it's a date field by name hint
+    field_name = field_obj.get("/T", "").lower()
+    if any(hint in field_name for hint in ["date", "fecha", "birth", "nacimiento"]):
+        return "date"
+
+    return base