-- Destructive cleanup for the SOP single-version migration.
-- Run only after the backfill script completed and all sop_id values are set.
-- The statements discover constraint/index names because deployments may use
-- different GORM naming conventions.

-- The application does not use database foreign keys. Remove every existing
-- foreign key in the database first so no historical constraint remains and
-- no constraint blocks the old SOP column cleanup.
DROP PROCEDURE IF EXISTS drop_all_iqudo_foreign_keys;
DELIMITER //
CREATE PROCEDURE drop_all_iqudo_foreign_keys()
BEGIN
  DECLARE finished INT DEFAULT 0;
  DECLARE table_name_value VARCHAR(64);
  DECLARE constraint_name_value VARCHAR(64);
  DECLARE foreign_keys CURSOR FOR
    SELECT TABLE_NAME, CONSTRAINT_NAME
    FROM information_schema.TABLE_CONSTRAINTS
    WHERE CONSTRAINT_SCHEMA = DATABASE() AND CONSTRAINT_TYPE = 'FOREIGN KEY';
  DECLARE CONTINUE HANDLER FOR NOT FOUND SET finished = 1;

  OPEN foreign_keys;
  drop_loop: LOOP
    FETCH foreign_keys INTO table_name_value, constraint_name_value;
    IF finished = 1 THEN
      LEAVE drop_loop;
    END IF;
    SET @sql = CONCAT('ALTER TABLE `', table_name_value, '` DROP FOREIGN KEY `', constraint_name_value, '`');
    PREPARE stmt_all_fk FROM @sql;
    EXECUTE stmt_all_fk;
    DEALLOCATE PREPARE stmt_all_fk;
  END LOOP;
  CLOSE foreign_keys;
END//
DELIMITER ;
CALL drop_all_iqudo_foreign_keys();
DROP PROCEDURE drop_all_iqudo_foreign_keys;

-- The following blocks are retained as idempotent guards for databases where
-- a concurrent/manual migration changed the schema between the procedure and
-- the SOP cleanup statements.
-- Remove foreign keys on the old sop_version_id columns, if present.
SET @fk = (
  SELECT kcu.CONSTRAINT_NAME FROM information_schema.KEY_COLUMN_USAGE kcu
  WHERE kcu.CONSTRAINT_SCHEMA = DATABASE() AND kcu.TABLE_NAME = 'sop_nodes'
    AND kcu.COLUMN_NAME = 'sop_version_id' AND kcu.REFERENCED_TABLE_NAME = 'sop_versions' LIMIT 1
);
SET @sql = IF(@fk IS NULL, 'SELECT 1', CONCAT('ALTER TABLE sop_nodes DROP FOREIGN KEY `', @fk, '`'));
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @fk = (
  SELECT kcu.CONSTRAINT_NAME FROM information_schema.KEY_COLUMN_USAGE kcu
  WHERE kcu.CONSTRAINT_SCHEMA = DATABASE() AND kcu.TABLE_NAME = 'sop_edges'
    AND kcu.COLUMN_NAME = 'sop_version_id' AND kcu.REFERENCED_TABLE_NAME = 'sop_versions' LIMIT 1
);
SET @sql = IF(@fk IS NULL, 'SELECT 1', CONCAT('ALTER TABLE sop_edges DROP FOREIGN KEY `', @fk, '`'));
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @fk = (
  SELECT kcu.CONSTRAINT_NAME FROM information_schema.KEY_COLUMN_USAGE kcu
  WHERE kcu.CONSTRAINT_SCHEMA = DATABASE() AND kcu.TABLE_NAME = 'sop_runs'
    AND kcu.COLUMN_NAME = 'sop_version_id' AND kcu.REFERENCED_TABLE_NAME = 'sop_versions' LIMIT 1
);
SET @sql = IF(@fk IS NULL, 'SELECT 1', CONCAT('ALTER TABLE sop_runs DROP FOREIGN KEY `', @fk, '`'));
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

-- Drop indexes containing the old column, regardless of their names.
SET @indexes = (
  SELECT GROUP_CONCAT(DISTINCT CONCAT('DROP INDEX `', INDEX_NAME, '`') SEPARATOR ', ')
  FROM information_schema.STATISTICS
  WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_nodes'
    AND COLUMN_NAME = 'sop_version_id' AND INDEX_NAME <> 'PRIMARY'
);
SET @sql = IF(@indexes IS NULL, 'SELECT 1', CONCAT('ALTER TABLE sop_nodes ', @indexes));
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @indexes = (
  SELECT GROUP_CONCAT(DISTINCT CONCAT('DROP INDEX `', INDEX_NAME, '`') SEPARATOR ', ')
  FROM information_schema.STATISTICS
  WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_edges'
    AND COLUMN_NAME = 'sop_version_id' AND INDEX_NAME <> 'PRIMARY'
);
SET @sql = IF(@indexes IS NULL, 'SELECT 1', CONCAT('ALTER TABLE sop_edges ', @indexes));
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @indexes = (
  SELECT GROUP_CONCAT(DISTINCT CONCAT('DROP INDEX `', INDEX_NAME, '`') SEPARATOR ', ')
  FROM information_schema.STATISTICS
  WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_runs'
    AND COLUMN_NAME = 'sop_version_id' AND INDEX_NAME <> 'PRIMARY'
);
SET @sql = IF(@indexes IS NULL, 'SELECT 1', CONCAT('ALTER TABLE sop_runs ', @indexes));
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

-- Add replacement indexes once.
SET @sql = IF(
  EXISTS (SELECT 1 FROM information_schema.STATISTICS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_nodes' AND INDEX_NAME = 'uk_sop_nodes_key'),
  'SELECT 1', 'ALTER TABLE sop_nodes ADD UNIQUE KEY uk_sop_nodes_key (sop_id, node_key)'
);
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @sql = IF(
  EXISTS (SELECT 1 FROM information_schema.STATISTICS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_edges' AND INDEX_NAME = 'idx_sop_edges_source'),
  'SELECT 1', 'ALTER TABLE sop_edges ADD INDEX idx_sop_edges_source (sop_id, source_node_key, priority)'
);
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

-- Drop old columns only when they still exist.
SET @sql = IF(
  EXISTS (SELECT 1 FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_nodes' AND COLUMN_NAME = 'sop_version_id'),
  'ALTER TABLE sop_nodes DROP COLUMN sop_version_id', 'SELECT 1'
);
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @sql = IF(
  EXISTS (SELECT 1 FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_edges' AND COLUMN_NAME = 'sop_version_id'),
  'ALTER TABLE sop_edges DROP COLUMN sop_version_id', 'SELECT 1'
);
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

SET @sql = IF(
  EXISTS (SELECT 1 FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = DATABASE() AND TABLE_NAME = 'sop_runs' AND COLUMN_NAME = 'sop_version_id'),
  'ALTER TABLE sop_runs DROP COLUMN sop_version_id', 'SELECT 1'
);
PREPARE stmt FROM @sql; EXECUTE stmt; DEALLOCATE PREPARE stmt;

DROP TABLE IF EXISTS sop_versions;