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Diffstat (limited to '')
-rw-r--r-- | course_groups.go | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/course_groups.go b/course_groups.go new file mode 100644 index 0000000..c1541ce --- /dev/null +++ b/course_groups.go @@ -0,0 +1,118 @@ +/* + * Course groups + * + * Copyright (C) 2024 Runxi Yu <https://runxiyu.org> + * SPDX-License-Identifier: AGPL-3.0-or-later + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU Affero General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU Affero General Public License for more details. + * + * You should have received a copy of the GNU Affero General Public License + * along with this program. If not, see <https://www.gnu.org/licenses/>. + */ + +package main + +import ( + "context" + "fmt" +) + +type userCourseGroupsT map[courseGroupT]struct{} + +type courseGroupT string + +func checkCourseGroup(cg courseGroupT) bool { + _, ok := courseGroups[cg] + return ok +} + +const ( + mw1 courseGroupT = "MW1" + mw2 courseGroupT = "MW2" + mw3 courseGroupT = "MW3" + tt1 courseGroupT = "TT1" + tt2 courseGroupT = "TT2" + tt3 courseGroupT = "TT3" +) + +var courseGroups = map[courseGroupT]string{ + mw1: "Monday/Wednesday CCA1", + mw2: "Monday/Wednesday CCA2", + mw3: "Monday/Wednesday CCA3", + tt1: "Tuesday/Thursday CCA1", + tt2: "Tuesday/Thursday CCA2", + tt3: "Tuesday/Thursday CCA3", +} + +func populateUserCourseGroups( + ctx context.Context, + userCourseGroups *userCourseGroupsT, + userID string, +) error { + rows, err := db.Query( + ctx, + "SELECT courseid FROM choices WHERE userid = $1", + userID, + ) + if err != nil { + return fmt.Errorf( + "%w: %w", + errUnexpectedDBError, + err, + ) + } + for { + if !rows.Next() { + err := rows.Err() + if err != nil { + return fmt.Errorf( + "%w: %w", + errUnexpectedDBError, + err, + ) + } + break + } + var thisCourseID int + err := rows.Scan(&thisCourseID) + if err != nil { + return fmt.Errorf( + "%w: %w", + errUnexpectedDBError, + err, + ) + } + var thisGroupName courseGroupT + _course, ok := courses.Load(thisCourseID) + if !ok { + return fmt.Errorf( + "%w: %d", + errNoSuchCourse, + thisCourseID, + ) + } + course, ok := _course.(*courseT) + if !ok { + panic("courses map has non-\"*courseT\" items") + } + thisGroupName = course.Group + if _, ok := (*userCourseGroups)[thisGroupName]; ok { + return fmt.Errorf( + "%w: user %v, group %v", + errMultipleChoicesInOneGroup, + userID, + thisGroupName, + ) + } + (*userCourseGroups)[thisGroupName] = struct{}{} + } + return nil +} |