Create biergarten brewery pipeline project (#199)

pipeline/src/data_generation/llama/generate_brewery.cc

@@ -0,0 +1,144 @@
+/**
+ * @file data_generation/llama/generate_brewery.cc
+ * @brief Builds brewery prompts with regional context, performs retry-based
+ * inference, and validates structured JSON output for brewery records.
+ */
+
+#include <spdlog/spdlog.h>
+
+#include <format>
+#include <optional>
+#include <stdexcept>
+#include <string>
+#include <string_view>
+#include <vector>
+
+#include "data_generation/llama_generator.h"
+#include "data_generation/llama_generator_helpers.h"
+
+static std::string FormatLocalLanguageCodes(
+    const std::vector<std::string>& codes) {
+  if (codes.empty()) {
+    return "Not provided";
+  }
+
+  std::string formatted;
+  for (const std::string& code : codes) {
+    if (!formatted.empty()) {
+      formatted += ", ";
+    }
+    formatted += code;
+  }
+
+  return formatted;
+}
+
+static constexpr std::string_view kBreweryJsonGrammar = R"json_brewery(
+root ::= thought-block "{" ws "\"name_en\"" ws ":" ws string ws "," ws "\"description_en\"" ws ":" ws string ws "," ws "\"name_local\"" ws ":" ws string ws "," ws "\"description_local\"" ws ":" ws string 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]
+)json_brewery";
+
+static constexpr int kBreweryInitialMaxTokens = 2800;
+
+BreweryResult LlamaGenerator::GenerateBrewery(
+    const Location& location, const std::string& region_context) {
+  /**
+   * Preprocess and truncate region context to manageable size
+   */
+  const std::string safe_region_context = PrepareRegionContext(region_context);
+
+  const std::string local_language_codes =
+      FormatLocalLanguageCodes(location.local_languages);
+
+  const std::string country_suffix =
+      location.country.empty() ? std::string{}
+                               : std::format(", {}", location.country);
+  /**
+   * Load brewery system prompt from file
+   * Falls back to minimal inline prompt if file not found
+   */
+  const std::string system_prompt =
+      LoadBrewerySystemPrompt("prompts/system.md");
+
+  std::string user_prompt = std::format(
+      "## CITY:\n{}\n\n## COUNTRY:\n{}\n\n## LOCAL LANGUAGE CODES:\n{}\n\n## "
+      "CONTEXT:\n{}",
+      location.city, location.country, local_language_codes,
+      safe_region_context);
+
+  /**
+   * Store location context for retry prompts (without repeating full context)
+   */
+  const std::string retry_location =
+      std::format("Location: {}{}\nLocal language codes: {}", location.city,
+                  country_suffix, local_language_codes);
+
+  /**
+   * RETRY LOOP with validation and error correction
+   * Attempts to generate valid brewery data up to 3 times, with feedback-based
+   * refinement
+   */
+  constexpr int max_attempts = 3;
+  std::string raw;
+  std::string last_error;
+
+  // Token budget: too small risks truncating valid JSON mid-string.
+  // Start conservatively but allow adaptive increases on truncation.
+  int max_tokens = kBreweryInitialMaxTokens;
+
+  // Limit output length to keep it concise and focused
+  for (int attempt = 0; attempt < max_attempts; ++attempt) {
+    // Generate brewery data from LLM
+    raw = this->Infer(system_prompt, user_prompt, max_tokens,
+                      kBreweryJsonGrammar);
+    spdlog::debug("LlamaGenerator: raw output (attempt {}): {}", attempt + 1,
+                  raw);
+
+    // Validate output: parse JSON and check required fields
+
+    BreweryResult brewery;
+    const std::optional<std::string> validation_error =
+        ValidateBreweryJson(raw, brewery);
+
+    if (!validation_error.has_value()) {
+      // Success: return parsed brewery data
+
+      spdlog::info(
+          "LlamaGenerator: successfully generated brewery data on attempt {}",
+          attempt + 1);
+
+      return brewery;
+    }
+
+    // Validation failed: log error and prepare corrective feedback
+
+    last_error = *validation_error;
+    spdlog::warn("LlamaGenerator: malformed brewery JSON (attempt {}): {}",
+                 attempt + 1, *validation_error);
+
+    // Update prompt with error details to guide LLM toward correct output.
+    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: {{\"name_en\": \"<English "
+        "brewery name>\", \"description_en\": \"<English single-paragraph "
+        "description>\", \"name_local\": \"<local-language brewery name>\", "
+        "\"description_local\": \"<local-language single-paragraph "
+        "description>\"}}.\nDo not include markdown, comments, extra keys, or "
+        "literal placeholder values.\n\nKeep the JSON strings concise enough "
+        "to fit within the token budget.\n\n{}",
+        *validation_error, retry_location);
+  }
+
+  // All retry attempts exhausted: log failure and throw exception
+  spdlog::error(
+      "LlamaGenerator: malformed brewery response after {} attempts: "
+      "{}",
+      max_attempts, last_error.empty() ? raw : last_error);
+  throw std::runtime_error("LlamaGenerator: malformed brewery response");
+}