Add user generation feature

tooling/pipeline/src/data_generation/llama/generate_user.cc

@@ -1,24 +1,121 @@
 /**
  * @file data_generation/llama/generate_user.cc
- * @brief Generates locale-aware user profiles with strict two-line formatting,
- * retry handling, and output sanitization for downstream parsing.
+ * @brief Builds persona/name-grounded user prompts, performs retry-based
+ * inference, and validates structured JSON output for user records.
  */
 
-
 #include <format>
+#include <optional>
+#include <stdexcept>
 #include <string>
+#include <string_view>
 
 #include "data_generation/llama_generator.h"
 #include "data_generation/llama_generator_helpers.h"
 
-// TODO: Implement locale-aware user profile generation.
-// Current implementation returns a hardcoded test value and ignores the
-// locale parameter. Future implementation should:
-// 1. Load a USER_GENERATION.md prompt template with locale context
-// 2. Perform LLM inference with locale-specific username/bio generation
-// 3. Parse and validate JSON output with retry handling (similar to brewery)
-// 4. Return locale-aware username and biography
-UserResult LlamaGenerator::GenerateUser(const std::string& locale) {
-  return {.username = "test_user",
-          .bio = std::format("This is a test user profile from {}.", locale)};
+// GBNF grammar for structured user JSON output.
+static constexpr std::string_view kUserJsonGrammar = R"json_user(
+root ::= thought-block "{" ws "\"username\"" ws ":" ws string ws "," ws "\"bio\"" ws ":" ws string ws "," ws "\"activity_weight\"" ws ":" ws number ws "}" ws
+thought-block ::= [^{]*
+ws ::= [ \t\n\r]*
+string ::= "\"" char+ "\""
+char ::= [^"\\\x7F\x00-\x1F] | [\\] escape
+escape ::= ["\\/bfnrt] | "u" hex hex hex hex
+hex ::= [0-9a-fA-F]
+number ::= "-"? ("0" | [1-9] [0-9]*) ("." [0-9]+)?
+)json_user";
+
+static constexpr int kUserInitialMaxTokens = 1200;
+
+UserResult LlamaGenerator::GenerateUser(const EnrichedCity& city,
+                                        const UserPersona& persona,
+                                        const Name& name) {
+  std::string style_affinities;
+  for (const std::string& style : persona.style_affinities) {
+    if (!style_affinities.empty()) {
+      style_affinities += ", ";
+    }
+    style_affinities += style;
+  }
+
+  const std::string system_prompt = prompt_directory_->Load("USER_GENERATION");
+
+  std::string user_prompt = std::format(
+      "## NAME:\n{} {}\n\n## GENDER:\n{}\n\n## CITY:\n{}\n\n## COUNTRY:\n{}\n\n"
+      "## PERSONA:\n{}\n\n## PERSONA DESCRIPTION:\n{}\n\n## STYLE "
+      "AFFINITIES:\n{}",
+      name.first_name, name.last_name, name.gender, city.location.city,
+      city.location.country, persona.name, persona.description,
+      style_affinities);
+
+  const std::string retry_context =
+      std::format("Name: {} {}\nCity: {}, {}\nPersona: {}", name.first_name,
+                 name.last_name, city.location.city, city.location.country,
+                 persona.name);
+
+  constexpr int max_attempts = 3;
+  std::string raw;
+  std::string last_error;
+  int max_tokens = kUserInitialMaxTokens;
+
+  for (int attempt = 0; attempt < max_attempts; ++attempt) {
+    raw = this->Infer(system_prompt, user_prompt, max_tokens,
+                      kUserJsonGrammar);
+    if (logger_) {
+      logger_->Log(
+          {.level = LogLevel::Debug,
+           .phase = PipelinePhase::UserGeneration,
+           .message = std::format("LlamaGenerator: raw output (attempt {}): {}",
+                      attempt + 1, raw)});
+    }
+
+    UserResult user;
+    const std::optional<std::string> validation_error =
+        ValidateUserJson(raw, user);
+
+    if (!validation_error.has_value()) {
+      if (logger_) {
+        logger_->Log(
+            {.level = LogLevel::Info,
+             .phase = PipelinePhase::UserGeneration,
+             .message = std::format("LlamaGenerator: successfully generated user data on attempt {}",
+                        attempt + 1)});
+      }
+
+      user.first_name = name.first_name;
+      user.last_name = name.last_name;
+      user.gender = name.gender;
+      return user;
+    }
+
+    last_error = *validation_error;
+    if (logger_) {
+      logger_->Log(
+          {.level = LogLevel::Warn,
+           .phase = PipelinePhase::UserGeneration,
+           .message =
+               std::format("LlamaGenerator: malformed user JSON (attempt {}): {}",
+               attempt + 1, *validation_error)});
+    }
+
+    user_prompt = std::format(
+        "Your previous response was invalid. Error: {}\nReturn the thought "
+        "process before the JSON if needed, then return ONLY valid JSON with "
+        "exactly these keys, in this exact order: {{\"username\": \"<handle "
+        "derived from the given name>\", \"bio\": \"<first-person bio "
+        "grounded in the persona>\", \"activity_weight\": <number between 0 "
+        "and 1>}}.\nDo not include markdown, comments, extra keys, or "
+        "literal placeholder values.\n\n{}",
+        *validation_error, retry_context);
+  }
+
+  if (logger_) {
+    logger_->Log(
+        {.level = LogLevel::Error,
+         .phase = PipelinePhase::UserGeneration,
+       .message = std::format(
+         "LlamaGenerator: malformed user response after {} attempts: {}",
+         max_attempts, last_error.empty() ? raw : last_error)});
+  }
+  throw std::runtime_error("LlamaGenerator: malformed user response");
 }