-- ==============================================================================
-- RailwaySystem 数据库 V2 迁移脚本: 005_constraints.sql
-- 适用数据库: KingbaseES V009R003C018 (schema: public)
-- 执行目标: 集中创建外键约束 (FK)、唯一约束 (UNIQUE) 与单行一致性检查约束 (CHECK)
-- 事务边界: 全程在显式事务 BEGIN ... COMMIT 中执行
-- 设计依据: RailwaySystem 数据库 V2 字段设计与 Kingbase DDL 规范 V1.0 及 Round 1 审查要求
-- 核心原则:
--   1. 所有外键严格使用 ON DELETE NO ACTION，严禁使用 CASCADE
--   2. 唯一约束保护核心领域关系防重
--   3. 检查约束全面覆盖单行时间、场地互斥、分值非负、容量合法及系统单号联动逻辑
-- ==============================================================================

BEGIN;

-- ==============================================================================
-- 一、唯一约束 (UNIQUE CONSTRAINTS - 共 13 组)
-- ==============================================================================

-- 1. 学员身份证哈希唯一 (允许 NULL，防重)
ALTER TABLE train_student DROP CONSTRAINT IF EXISTS uq_student_idcard_hash;
ALTER TABLE train_student ADD CONSTRAINT uq_student_idcard_hash UNIQUE (id_card_hash);

-- 2. 课程编码唯一 (允许 NULL)
ALTER TABLE train_course DROP CONSTRAINT IF EXISTS uq_course_code;
ALTER TABLE train_course ADD CONSTRAINT uq_course_code UNIQUE (c_code);

-- 3. 电子班牌硬件序列号全局唯一
ALTER TABLE train_electronic_board DROP CONSTRAINT IF EXISTS uq_board_sn;
ALTER TABLE train_electronic_board ADD CONSTRAINT uq_board_sn UNIQUE (board_sn);

-- 4. 宿舍房间唯一 (楼栋 + 房号)
ALTER TABLE train_dormitory_info DROP CONSTRAINT IF EXISTS uq_dorm_building_room;
ALTER TABLE train_dormitory_info ADD CONSTRAINT uq_dorm_building_room UNIQUE (dorm_building, dorm_room);

-- 5. 课程与教学资源绑定唯一
ALTER TABLE train_course_resource DROP CONSTRAINT IF EXISTS uq_course_resource;
ALTER TABLE train_course_resource ADD CONSTRAINT uq_course_resource UNIQUE (c_id, resource_id);

-- 6. 培训班与课程关联唯一 (一个班不能重复加入同一门课)
ALTER TABLE train_plan_course DROP CONSTRAINT IF EXISTS uq_plan_course;
ALTER TABLE train_plan_course ADD CONSTRAINT uq_plan_course UNIQUE (plan_id, c_id);

-- 7. 参训学员档案唯一 (同一学员不能重复加入同一培训班)
ALTER TABLE train_enrollment DROP CONSTRAINT IF EXISTS uq_enrollment;
ALTER TABLE train_enrollment ADD CONSTRAINT uq_enrollment UNIQUE (plan_id, student_id);

-- 8. 住宿安排唯一 (一次参训保留一个有效住宿记录)
ALTER TABLE train_accommodation DROP CONSTRAINT IF EXISTS uq_accommodation_enroll;
ALTER TABLE train_accommodation ADD CONSTRAINT uq_accommodation_enroll UNIQUE (enrollment_id);

-- 9. 门禁授权唯一 (一次住宿安排对应一条门禁同步主记录)
ALTER TABLE train_dorm_auth DROP CONSTRAINT IF EXISTS uq_dorm_auth_accomm;
ALTER TABLE train_dorm_auth ADD CONSTRAINT uq_dorm_auth_accomm UNIQUE (accommodation_id);

-- 10. 报到记录唯一 (一次参训对应一次报到结果)
ALTER TABLE train_class_report DROP CONSTRAINT IF EXISTS uq_class_report_enroll;
ALTER TABLE train_class_report ADD CONSTRAINT uq_class_report_enroll UNIQUE (enrollment_id);

-- 11. 课次考勤打卡唯一 (一个学员在一堂课只有一条考勤主结果)
ALTER TABLE train_student_checkin DROP CONSTRAINT IF EXISTS uq_student_checkin_enroll_lesson;
ALTER TABLE train_student_checkin ADD CONSTRAINT uq_student_checkin_enroll_lesson UNIQUE (enrollment_id, lesson_id);

-- 12. 学员考核项成绩唯一 (一个学员在某考核项只有一条最终得分)
ALTER TABLE train_student_score DROP CONSTRAINT IF EXISTS uq_student_score_enroll_item;
ALTER TABLE train_student_score ADD CONSTRAINT uq_student_score_enroll_item UNIQUE (enrollment_id, score_item_id);

-- 13. 学员参训综合画像唯一 (一次参训生成一份画像)
ALTER TABLE train_student_portrait DROP CONSTRAINT IF EXISTS uq_student_portrait_enroll;
ALTER TABLE train_student_portrait ADD CONSTRAINT uq_student_portrait_enroll UNIQUE (enrollment_id);


-- ==============================================================================
-- 二、外键约束 (FOREIGN KEY CONSTRAINTS - 共 26 组，全部 ON DELETE NO ACTION)
-- ==============================================================================

-- 1. train_course_resource (2 FK)
ALTER TABLE train_course_resource DROP CONSTRAINT IF EXISTS fk_cr_course;
ALTER TABLE train_course_resource ADD CONSTRAINT fk_cr_course 
    FOREIGN KEY (c_id) REFERENCES train_course (c_id) ON DELETE NO ACTION;

ALTER TABLE train_course_resource DROP CONSTRAINT IF EXISTS fk_cr_resource;
ALTER TABLE train_course_resource ADD CONSTRAINT fk_cr_resource 
    FOREIGN KEY (resource_id) REFERENCES train_resource (resource_id) ON DELETE NO ACTION;

-- 2. train_electronic_board (1 FK)
ALTER TABLE train_electronic_board DROP CONSTRAINT IF EXISTS fk_board_classroom;
ALTER TABLE train_electronic_board ADD CONSTRAINT fk_board_classroom 
    FOREIGN KEY (bind_classroom_id) REFERENCES train_classroom_info (class_room_id) ON DELETE NO ACTION;

-- 3. train_plan_course (2 FK)
ALTER TABLE train_plan_course DROP CONSTRAINT IF EXISTS fk_plancourse_plan;
ALTER TABLE train_plan_course ADD CONSTRAINT fk_plancourse_plan 
    FOREIGN KEY (plan_id) REFERENCES train_class_plan (plan_id) ON DELETE NO ACTION;

ALTER TABLE train_plan_course DROP CONSTRAINT IF EXISTS fk_plancourse_course;
ALTER TABLE train_plan_course ADD CONSTRAINT fk_plancourse_course 
    FOREIGN KEY (c_id) REFERENCES train_course (c_id) ON DELETE NO ACTION;

-- 4. train_enrollment (2 FK)
ALTER TABLE train_enrollment DROP CONSTRAINT IF EXISTS fk_enrollment_plan;
ALTER TABLE train_enrollment ADD CONSTRAINT fk_enrollment_plan 
    FOREIGN KEY (plan_id) REFERENCES train_class_plan (plan_id) ON DELETE NO ACTION;

ALTER TABLE train_enrollment DROP CONSTRAINT IF EXISTS fk_enrollment_student;
ALTER TABLE train_enrollment ADD CONSTRAINT fk_enrollment_student 
    FOREIGN KEY (student_id) REFERENCES train_student (s_id) ON DELETE NO ACTION;

-- 5. train_lesson (4 FK)
ALTER TABLE train_lesson DROP CONSTRAINT IF EXISTS fk_lesson_plancourse;
ALTER TABLE train_lesson ADD CONSTRAINT fk_lesson_plancourse 
    FOREIGN KEY (plan_course_id) REFERENCES train_plan_course (plan_course_id) ON DELETE NO ACTION;

ALTER TABLE train_lesson DROP CONSTRAINT IF EXISTS fk_lesson_teacher;
ALTER TABLE train_lesson ADD CONSTRAINT fk_lesson_teacher 
    FOREIGN KEY (t_id) REFERENCES train_teacher (t_id) ON DELETE NO ACTION;

ALTER TABLE train_lesson DROP CONSTRAINT IF EXISTS fk_lesson_classroom;
ALTER TABLE train_lesson ADD CONSTRAINT fk_lesson_classroom 
    FOREIGN KEY (class_room_id) REFERENCES train_classroom_info (class_room_id) ON DELETE NO ACTION;

ALTER TABLE train_lesson DROP CONSTRAINT IF EXISTS fk_lesson_site;
ALTER TABLE train_lesson ADD CONSTRAINT fk_lesson_site 
    FOREIGN KEY (site_id) REFERENCES train_training_site (site_id) ON DELETE NO ACTION;

-- 6. train_accommodation (2 FK)
ALTER TABLE train_accommodation DROP CONSTRAINT IF EXISTS fk_accomm_enrollment;
ALTER TABLE train_accommodation ADD CONSTRAINT fk_accomm_enrollment 
    FOREIGN KEY (enrollment_id) REFERENCES train_enrollment (enrollment_id) ON DELETE NO ACTION;

ALTER TABLE train_accommodation DROP CONSTRAINT IF EXISTS fk_accomm_dorm;
ALTER TABLE train_accommodation ADD CONSTRAINT fk_accomm_dorm 
    FOREIGN KEY (dorm_id) REFERENCES train_dormitory_info (dorm_id) ON DELETE NO ACTION;

-- 7. train_dorm_auth (1 FK)
ALTER TABLE train_dorm_auth DROP CONSTRAINT IF EXISTS fk_dormauth_accomm;
ALTER TABLE train_dorm_auth ADD CONSTRAINT fk_dormauth_accomm 
    FOREIGN KEY (accommodation_id) REFERENCES train_accommodation (accommodation_id) ON DELETE NO ACTION;

-- 8. train_class_report (1 FK)
ALTER TABLE train_class_report DROP CONSTRAINT IF EXISTS fk_report_enrollment;
ALTER TABLE train_class_report ADD CONSTRAINT fk_report_enrollment 
    FOREIGN KEY (enrollment_id) REFERENCES train_enrollment (enrollment_id) ON DELETE NO ACTION;

-- 9. train_student_checkin (3 FK)
ALTER TABLE train_student_checkin DROP CONSTRAINT IF EXISTS fk_checkin_enrollment;
ALTER TABLE train_student_checkin ADD CONSTRAINT fk_checkin_enrollment 
    FOREIGN KEY (enrollment_id) REFERENCES train_enrollment (enrollment_id) ON DELETE NO ACTION;

ALTER TABLE train_student_checkin DROP CONSTRAINT IF EXISTS fk_checkin_lesson;
ALTER TABLE train_student_checkin ADD CONSTRAINT fk_checkin_lesson 
    FOREIGN KEY (lesson_id) REFERENCES train_lesson (lesson_id) ON DELETE NO ACTION;

ALTER TABLE train_student_checkin DROP CONSTRAINT IF EXISTS fk_checkin_board;
ALTER TABLE train_student_checkin ADD CONSTRAINT fk_checkin_board 
    FOREIGN KEY (board_id) REFERENCES train_electronic_board (board_id) ON DELETE NO ACTION;

-- 10. train_score_item (2 FK)
ALTER TABLE train_score_item DROP CONSTRAINT IF EXISTS fk_scoreitem_plan;
ALTER TABLE train_score_item ADD CONSTRAINT fk_scoreitem_plan 
    FOREIGN KEY (plan_id) REFERENCES train_class_plan (plan_id) ON DELETE NO ACTION;

ALTER TABLE train_score_item DROP CONSTRAINT IF EXISTS fk_scoreitem_plancourse;
ALTER TABLE train_score_item ADD CONSTRAINT fk_scoreitem_plancourse 
    FOREIGN KEY (plan_course_id) REFERENCES train_plan_course (plan_course_id) ON DELETE NO ACTION;

-- 11. train_student_score (2 FK)
ALTER TABLE train_student_score DROP CONSTRAINT IF EXISTS fk_score_enrollment;
ALTER TABLE train_student_score ADD CONSTRAINT fk_score_enrollment 
    FOREIGN KEY (enrollment_id) REFERENCES train_enrollment (enrollment_id) ON DELETE NO ACTION;

ALTER TABLE train_student_score DROP CONSTRAINT IF EXISTS fk_score_item;
ALTER TABLE train_student_score ADD CONSTRAINT fk_score_item 
    FOREIGN KEY (score_item_id) REFERENCES train_score_item (score_item_id) ON DELETE NO ACTION;

-- 12. train_study_duration (3 FK)
ALTER TABLE train_study_duration DROP CONSTRAINT IF EXISTS fk_study_enrollment;
ALTER TABLE train_study_duration ADD CONSTRAINT fk_study_enrollment 
    FOREIGN KEY (enrollment_id) REFERENCES train_enrollment (enrollment_id) ON DELETE NO ACTION;

ALTER TABLE train_study_duration DROP CONSTRAINT IF EXISTS fk_study_plancourse;
ALTER TABLE train_study_duration ADD CONSTRAINT fk_study_plancourse 
    FOREIGN KEY (plan_course_id) REFERENCES train_plan_course (plan_course_id) ON DELETE NO ACTION;

ALTER TABLE train_study_duration DROP CONSTRAINT IF EXISTS fk_study_resource;
ALTER TABLE train_study_duration ADD CONSTRAINT fk_study_resource 
    FOREIGN KEY (resource_id) REFERENCES train_resource (resource_id) ON DELETE NO ACTION;

-- 13. train_student_portrait (1 FK)
ALTER TABLE train_student_portrait DROP CONSTRAINT IF EXISTS fk_portrait_enrollment;
ALTER TABLE train_student_portrait ADD CONSTRAINT fk_portrait_enrollment 
    FOREIGN KEY (enrollment_id) REFERENCES train_enrollment (enrollment_id) ON DELETE NO ACTION;


-- ==============================================================================
-- 三、单行检查约束 (CHECK CONSTRAINTS)
-- ==============================================================================

-- 1. 排课时间逻辑检查: 开始时间必须早于结束时间
ALTER TABLE train_lesson DROP CONSTRAINT IF EXISTS chk_lesson_time;
ALTER TABLE train_lesson ADD CONSTRAINT chk_lesson_time 
    CHECK (start_time < end_time);

-- 2. 排课场地类型单行互斥约束
ALTER TABLE train_lesson DROP CONSTRAINT IF EXISTS chk_lesson_venue;
ALTER TABLE train_lesson ADD CONSTRAINT chk_lesson_venue CHECK (
    (venue_type = 1 AND class_room_id IS NOT NULL AND site_id IS NULL) OR
    (venue_type = 2 AND site_id IS NOT NULL AND class_room_id IS NULL)
);

-- 3. 成绩项目单项权重范围: 0 ~ 100
ALTER TABLE train_score_item DROP CONSTRAINT IF EXISTS chk_score_item_weight;
ALTER TABLE train_score_item ADD CONSTRAINT chk_score_item_weight 
    CHECK (weight >= 0.00 AND weight <= 100.00);

-- 4. 成绩项目满分设定: 必须大于 0
ALTER TABLE train_score_item DROP CONSTRAINT IF EXISTS chk_score_item_full;
ALTER TABLE train_score_item ADD CONSTRAINT chk_score_item_full 
    CHECK (full_score > 0.00);

-- 5. 学员得分非负约束 (未录成绩不建行，录入则非负)
ALTER TABLE train_student_score DROP CONSTRAINT IF EXISTS chk_student_score_nonneg;
ALTER TABLE train_student_score ADD CONSTRAINT chk_student_score_nonneg 
    CHECK (score >= 0.00);

-- 6. 学习时长非负检查
ALTER TABLE train_study_duration DROP CONSTRAINT IF EXISTS chk_study_seconds;
ALTER TABLE train_study_duration ADD CONSTRAINT chk_study_seconds 
    CHECK (study_seconds >= 0);

-- 7. 学习记录时间逻辑检查
ALTER TABLE train_study_duration DROP CONSTRAINT IF EXISTS chk_study_time;
ALTER TABLE train_study_duration ADD CONSTRAINT chk_study_time 
    CHECK (end_time IS NULL OR start_time IS NULL OR end_time >= start_time);

-- 8. 学习记录外部单号与来源系统一致性检查
ALTER TABLE train_study_duration DROP CONSTRAINT IF EXISTS chk_study_source_system;
ALTER TABLE train_study_duration ADD CONSTRAINT chk_study_source_system 
    CHECK (source_event_id IS NULL OR source_system IS NOT NULL);

-- 9. 宿舍核定容量正数检查
ALTER TABLE train_dormitory_info DROP CONSTRAINT IF EXISTS chk_dorm_capacity;
ALTER TABLE train_dormitory_info ADD CONSTRAINT chk_dorm_capacity 
    CHECK (capacity > 0);

COMMIT;