feat: rebuild CSP practice workflow, UX and automation

backend/tests/problem_service_test.cc

@@ -0,0 +1,50 @@
+#include <catch2/catch_test_macros.hpp>
+
+#include "csp/db/sqlite_db.h"
+#include "csp/services/problem_service.h"
+
+TEST_CASE("problem service list/get") {
+  auto db = csp::db::SqliteDb::OpenMemory();
+  csp::db::ApplyMigrations(db);
+  csp::db::SeedDemoData(db);
+
+  db.Exec(
+      "INSERT INTO problems(slug,title,statement_md,difficulty,source,statement_url,llm_profile_json,"
+      "sample_input,sample_output,created_at)"
+      "VALUES('luogu-p1000','P1000','x',2,'luogu:P1000','https://www.luogu.com.cn/problem/P1000','{}','','',100);");
+  db.Exec(
+      "INSERT INTO problems(slug,title,statement_md,difficulty,source,statement_url,llm_profile_json,"
+      "sample_input,sample_output,created_at)"
+      "VALUES('luogu-p1001','P1001','x',3,'luogu:P1001','https://www.luogu.com.cn/problem/P1001','{}','','',100);");
+  db.Exec("INSERT INTO problem_tags(problem_id,tag) VALUES((SELECT id FROM problems WHERE slug='luogu-p1000'),'csp-j');");
+  db.Exec("INSERT INTO problem_tags(problem_id,tag) VALUES((SELECT id FROM problems WHERE slug='luogu-p1001'),'csp-s');");
+
+  csp::services::ProblemService svc(db);
+
+  csp::services::ProblemQuery q_all;
+  const auto all = svc.List(q_all);
+  REQUIRE(all.total_count >= 5);
+  REQUIRE(all.items.size() >= 5);
+
+  csp::services::ProblemQuery q_dp;
+  q_dp.tag = "dp";
+  const auto dp = svc.List(q_dp);
+  REQUIRE(dp.total_count >= 1);
+  REQUIRE(dp.items.size() >= 1);
+
+  csp::services::ProblemQuery q_source;
+  q_source.source_prefix = "luogu:";
+  const auto luogu = svc.List(q_source);
+  REQUIRE(luogu.total_count == 2);
+  REQUIRE(luogu.items.size() == 2);
+
+  csp::services::ProblemQuery q_tags;
+  q_tags.tags = {"csp-j", "csp-s"};
+  const auto csp = svc.List(q_tags);
+  REQUIRE(csp.total_count == 2);
+  REQUIRE(csp.items.size() == 2);
+
+  const auto one = svc.GetById(all.items.front().id);
+  REQUIRE(one.has_value());
+  REQUIRE(one->id == all.items.front().id);
+}