feat: rebuild CSP practice workflow, UX and automation

backend/src/services/wrong_book_service.cc

@@ -0,0 +1,123 @@
+#include "csp/services/wrong_book_service.h"
+
+#include <sqlite3.h>
+
+#include <chrono>
+#include <stdexcept>
+#include <string>
+
+namespace csp::services {
+
+namespace {
+
+void CheckSqlite(int rc, sqlite3* db, const char* what) {
+  if (rc == SQLITE_OK || rc == SQLITE_ROW || rc == SQLITE_DONE) return;
+  throw std::runtime_error(std::string(what) + ": " + sqlite3_errmsg(db));
+}
+
+int64_t NowSec() {
+  using namespace std::chrono;
+  return duration_cast<std::chrono::seconds>(
+             std::chrono::system_clock::now().time_since_epoch())
+      .count();
+}
+
+std::string ColText(sqlite3_stmt* stmt, int col) {
+  const unsigned char* txt = sqlite3_column_text(stmt, col);
+  return txt ? reinterpret_cast<const char*>(txt) : std::string();
+}
+
+}  // namespace
+
+std::vector<WrongBookEntry> WrongBookService::ListByUser(int64_t user_id) {
+  sqlite3* db = db_.raw();
+  sqlite3_stmt* stmt = nullptr;
+  const char* sql =
+      "SELECT w.user_id,w.problem_id,w.last_submission_id,w.note,w.updated_at,p.title "
+      "FROM wrong_book w "
+      "JOIN problems p ON p.id=w.problem_id "
+      "WHERE w.user_id=? ORDER BY w.updated_at DESC";
+  CheckSqlite(sqlite3_prepare_v2(db, sql, -1, &stmt, nullptr), db,
+              "prepare wrong_book list");
+  CheckSqlite(sqlite3_bind_int64(stmt, 1, user_id), db, "bind user_id");
+
+  std::vector<WrongBookEntry> out;
+  while (sqlite3_step(stmt) == SQLITE_ROW) {
+    WrongBookEntry e;
+    e.item.user_id = sqlite3_column_int64(stmt, 0);
+    e.item.problem_id = sqlite3_column_int64(stmt, 1);
+    if (sqlite3_column_type(stmt, 2) == SQLITE_NULL) {
+      e.item.last_submission_id = std::nullopt;
+    } else {
+      e.item.last_submission_id = sqlite3_column_int64(stmt, 2);
+    }
+    e.item.note = ColText(stmt, 3);
+    e.item.updated_at = sqlite3_column_int64(stmt, 4);
+    e.problem_title = ColText(stmt, 5);
+    out.push_back(std::move(e));
+  }
+  sqlite3_finalize(stmt);
+  return out;
+}
+
+void WrongBookService::UpsertNote(int64_t user_id,
+                                  int64_t problem_id,
+                                  const std::string& note) {
+  sqlite3* db = db_.raw();
+  sqlite3_stmt* stmt = nullptr;
+  const char* sql =
+      "INSERT INTO wrong_book(user_id,problem_id,last_submission_id,note,updated_at) "
+      "VALUES(?,?,?,?,?) "
+      "ON CONFLICT(user_id,problem_id) DO UPDATE SET note=excluded.note,updated_at=excluded.updated_at";
+  CheckSqlite(sqlite3_prepare_v2(db, sql, -1, &stmt, nullptr), db,
+              "prepare wrong_book upsert note");
+  CheckSqlite(sqlite3_bind_int64(stmt, 1, user_id), db, "bind user_id");
+  CheckSqlite(sqlite3_bind_int64(stmt, 2, problem_id), db, "bind problem_id");
+  CheckSqlite(sqlite3_bind_null(stmt, 3), db, "bind last_submission_id");
+  CheckSqlite(sqlite3_bind_text(stmt, 4, note.c_str(), -1, SQLITE_TRANSIENT), db,
+              "bind note");
+  CheckSqlite(sqlite3_bind_int64(stmt, 5, NowSec()), db, "bind updated_at");
+  CheckSqlite(sqlite3_step(stmt), db, "wrong_book upsert note");
+  sqlite3_finalize(stmt);
+}
+
+void WrongBookService::UpsertBySubmission(int64_t user_id,
+                                          int64_t problem_id,
+                                          int64_t submission_id,
+                                          const std::string& note) {
+  sqlite3* db = db_.raw();
+  sqlite3_stmt* stmt = nullptr;
+  const char* sql =
+      "INSERT INTO wrong_book(user_id,problem_id,last_submission_id,note,updated_at) "
+      "VALUES(?,?,?,?,?) "
+      "ON CONFLICT(user_id,problem_id) DO UPDATE SET "
+      "last_submission_id=excluded.last_submission_id,"
+      "updated_at=excluded.updated_at,"
+      "note=CASE WHEN wrong_book.note='' THEN excluded.note ELSE wrong_book.note END";
+
+  CheckSqlite(sqlite3_prepare_v2(db, sql, -1, &stmt, nullptr), db,
+              "prepare wrong_book upsert by submission");
+  CheckSqlite(sqlite3_bind_int64(stmt, 1, user_id), db, "bind user_id");
+  CheckSqlite(sqlite3_bind_int64(stmt, 2, problem_id), db, "bind problem_id");
+  CheckSqlite(sqlite3_bind_int64(stmt, 3, submission_id), db,
+              "bind submission_id");
+  CheckSqlite(sqlite3_bind_text(stmt, 4, note.c_str(), -1, SQLITE_TRANSIENT), db,
+              "bind note");
+  CheckSqlite(sqlite3_bind_int64(stmt, 5, NowSec()), db, "bind updated_at");
+  CheckSqlite(sqlite3_step(stmt), db, "wrong_book upsert by submission");
+  sqlite3_finalize(stmt);
+}
+
+void WrongBookService::Remove(int64_t user_id, int64_t problem_id) {
+  sqlite3* db = db_.raw();
+  sqlite3_stmt* stmt = nullptr;
+  const char* sql = "DELETE FROM wrong_book WHERE user_id=? AND problem_id=?";
+  CheckSqlite(sqlite3_prepare_v2(db, sql, -1, &stmt, nullptr), db,
+              "prepare wrong_book delete");
+  CheckSqlite(sqlite3_bind_int64(stmt, 1, user_id), db, "bind user_id");
+  CheckSqlite(sqlite3_bind_int64(stmt, 2, problem_id), db, "bind problem_id");
+  CheckSqlite(sqlite3_step(stmt), db, "wrong_book delete");
+  sqlite3_finalize(stmt);
+}
+
+}  // namespace csp::services