//go:build ignore

package main

import (
	"database/sql"
	"fmt"
	"os"
	"strings"

	_ "github.com/go-sql-driver/mysql"
)

func main() {
	dsn := strings.TrimPrefix(os.Getenv("IM_MYSQL_DSN"), "mysql://")
	if dsn == "" {
		fatal("IM_MYSQL_DSN is required")
	}
	db, err := sql.Open("mysql", dsn)
	if err != nil {
		fatal(err)
	}
	defer db.Close()
	if err = db.Ping(); err != nil {
		fatal(err)
	}

	statements := []string{
		"CREATE DATABASE IF NOT EXISTS hotgo CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci",
		`CREATE TABLE IF NOT EXISTS hotgo.im_tenant(
			id           BIGINT NOT NULL AUTO_INCREMENT,
			code         VARCHAR(64) NOT NULL,
			name         VARCHAR(128) NOT NULL,
			tenant_desc  VARCHAR(256),
			db_name      VARCHAR(128) NOT NULL DEFAULT '',
			db_dsn       VARCHAR(1024) NOT NULL DEFAULT '',
			state        SMALLINT NOT NULL,
			created_at   DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
			created_by   BIGINT NOT NULL,
			updated_at   DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3),
			updated_by   BIGINT NOT NULL,
			PRIMARY KEY(id),
			UNIQUE INDEX uk_im_tenant_code(code)
		) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci`,
		`CREATE TABLE IF NOT EXISTS hotgo.im_tenant_config(
			id                BIGINT NOT NULL AUTO_INCREMENT,
			tenant_id         BIGINT NOT NULL,
			max_users         BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT '0 means unlimited',
			max_groups        BIGINT UNSIGNED NOT NULL DEFAULT 0 COMMENT '0 means unlimited',
			max_group_members INT UNSIGNED NOT NULL DEFAULT 0 COMMENT '0 means unlimited',
			created_at        DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
			created_by        BIGINT NOT NULL,
			updated_at        DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3),
			updated_by        BIGINT NOT NULL,
			PRIMARY KEY(id),
			UNIQUE INDEX uk_im_tenant_config_tenant_id(tenant_id),
			CONSTRAINT fk_im_tenant_config_tenant FOREIGN KEY(tenant_id) REFERENCES hotgo.im_tenant(id) ON DELETE CASCADE
		) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci`,
		"CREATE DATABASE IF NOT EXISTS tinode CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci",
		`CREATE TABLE IF NOT EXISTS tinode.im_call_records(
			id          BIGINT NOT NULL AUTO_INCREMENT,
			call_id     VARCHAR(64) NOT NULL,
			topic       CHAR(25) NOT NULL,
			seq_id      INT NOT NULL,
			caller_id   BIGINT NOT NULL,
			callee_id   BIGINT NOT NULL,
			call_type   VARCHAR(16) NOT NULL,
			status      VARCHAR(32) NOT NULL,
			end_reason  VARCHAR(64) NOT NULL DEFAULT '',
			duration_ms BIGINT NOT NULL DEFAULT 0,
			started_at  DATETIME(3) NOT NULL,
			accepted_at DATETIME(3),
			finished_at DATETIME(3),
			created_at  DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3),
			updated_at  DATETIME(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3) ON UPDATE CURRENT_TIMESTAMP(3),
			PRIMARY KEY(id),
			UNIQUE INDEX uk_im_call_records_call(call_id),
			UNIQUE INDEX uk_im_call_records_topic_seq(topic, seq_id),
			INDEX idx_im_call_records_caller(caller_id, id DESC),
			INDEX idx_im_call_records_callee(callee_id, id DESC),
			INDEX idx_im_call_records_status(status, updated_at)
		) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci`,
	}
	for _, stmt := range statements {
		if _, err = db.Exec(stmt); err != nil {
			fatal(fmt.Errorf("exec failed: %s: %w", stmt, err))
		}
	}
	for _, stmt := range []string{
		"ALTER TABLE hotgo.im_tenant ADD COLUMN tenant_desc VARCHAR(256) AFTER name",
		"ALTER TABLE hotgo.im_tenant ADD COLUMN db_name VARCHAR(128) NOT NULL DEFAULT '' AFTER tenant_desc",
		"ALTER TABLE hotgo.im_tenant ADD COLUMN db_dsn VARCHAR(1024) NOT NULL DEFAULT '' AFTER db_name",
		"ALTER TABLE tinode.im_tenant ADD COLUMN tenant_desc VARCHAR(256) AFTER name",
		"ALTER TABLE tinode.im_tenant ADD COLUMN db_name VARCHAR(128) NOT NULL DEFAULT '' AFTER tenant_desc",
		"ALTER TABLE tinode.im_tenant ADD COLUMN db_dsn VARCHAR(1024) NOT NULL DEFAULT '' AFTER db_name",
	} {
		if _, err = db.Exec(stmt); err != nil && !strings.Contains(err.Error(), "Duplicate column name") {
			fatal(fmt.Errorf("exec failed: %s: %w", stmt, err))
		}
	}
	if _, err = db.Exec(`INSERT INTO hotgo.im_tenant(code,name,tenant_desc,db_name,db_dsn,state,created_by,updated_by)
		VALUES('default','Default Tenant',NULL,'tinode','',1,0,0)
		ON DUPLICATE KEY UPDATE name=VALUES(name), db_name=VALUES(db_name), updated_at=CURRENT_TIMESTAMP(3)`); err != nil {
		fatal(err)
	}
	if _, err = db.Exec(`INSERT INTO hotgo.im_tenant_config(tenant_id,max_users,max_groups,max_group_members,created_by,updated_by)
		SELECT id,0,0,0,0,0 FROM hotgo.im_tenant WHERE code='default'
		ON DUPLICATE KEY UPDATE updated_at=CURRENT_TIMESTAMP(3)`); err != nil {
		fatal(err)
	}
	if _, err = db.Exec("UPDATE tinode.im_tenant SET db_name='tinode' WHERE code='default' AND (db_name='' OR db_name IS NULL)"); err != nil {
		fatal(err)
	}
	if err = dropTenantIDColumns(db, "tinode"); err != nil {
		fatal(err)
	}

	var code, dbName string
	var state int
	if err = db.QueryRow("SELECT code, db_name, state FROM hotgo.im_tenant WHERE code='default'").Scan(&code, &dbName, &state); err != nil {
		fatal(err)
	}
	fmt.Printf("hotgo.im_tenant default: code=%s db_name=%s state=%d\n", code, dbName, state)
	var columnCount int
	if err = db.QueryRow(`SELECT COUNT(*) FROM information_schema.COLUMNS
		WHERE TABLE_SCHEMA='tinode' AND TABLE_NAME='im_tenant' AND COLUMN_NAME IN ('tenant_desc','db_name','db_dsn')`).Scan(&columnCount); err != nil {
		fatal(err)
	}
	fmt.Printf("tinode.im_tenant routing columns: %d/3\n", columnCount)

	rows, err := db.Query(`SELECT table_name FROM information_schema.COLUMNS
		WHERE TABLE_SCHEMA='tinode' AND COLUMN_NAME='tenant_id'
		ORDER BY table_name`)
	if err != nil {
		fatal(err)
	}
	defer rows.Close()
	var tables []string
	for rows.Next() {
		var table string
		if err = rows.Scan(&table); err != nil {
			fatal(err)
		}
		tables = append(tables, table)
	}
	if err = rows.Err(); err != nil {
		fatal(err)
	}
	if len(tables) == 0 {
		fmt.Println("tinode tenant_id columns: none")
	} else {
		fmt.Printf("tinode tenant_id columns: %s\n", strings.Join(tables, ","))
	}
}

func fatal(v any) {
	fmt.Fprintln(os.Stderr, v)
	os.Exit(1)
}

func dropTenantIDColumns(db *sql.DB, schema string) error {
	fks, err := queryPairs(db, `SELECT DISTINCT table_name, constraint_name
		FROM information_schema.KEY_COLUMN_USAGE
		WHERE TABLE_SCHEMA=? AND COLUMN_NAME='tenant_id' AND REFERENCED_TABLE_NAME IS NOT NULL`,
		schema)
	if err != nil {
		return err
	}
	for _, fk := range fks {
		if _, err = db.Exec("ALTER TABLE " + quoteIdent(schema) + "." + quoteIdent(fk[0]) + " DROP FOREIGN KEY " + quoteIdent(fk[1])); err != nil {
			return fmt.Errorf("drop foreign key %s.%s: %w", fk[0], fk[1], err)
		}
	}

	indexes, err := queryPairs(db, `SELECT DISTINCT table_name, index_name
		FROM information_schema.STATISTICS
		WHERE TABLE_SCHEMA=? AND COLUMN_NAME='tenant_id' AND INDEX_NAME<>'PRIMARY'`,
		schema)
	if err != nil {
		return err
	}
	for _, idx := range indexes {
		if _, err = db.Exec("ALTER TABLE " + quoteIdent(schema) + "." + quoteIdent(idx[0]) + " DROP INDEX " + quoteIdent(idx[1])); err != nil {
			return fmt.Errorf("drop index %s.%s: %w", idx[0], idx[1], err)
		}
	}

	rows, err := db.Query(`SELECT table_name FROM information_schema.COLUMNS
		WHERE TABLE_SCHEMA=? AND COLUMN_NAME='tenant_id'
		ORDER BY table_name`, schema)
	if err != nil {
		return err
	}
	defer rows.Close()
	var tables []string
	for rows.Next() {
		var table string
		if err = rows.Scan(&table); err != nil {
			return err
		}
		tables = append(tables, table)
	}
	if err = rows.Err(); err != nil {
		return err
	}
	for _, table := range tables {
		if _, err = db.Exec("ALTER TABLE " + quoteIdent(schema) + "." + quoteIdent(table) + " DROP COLUMN tenant_id"); err != nil {
			return fmt.Errorf("drop column %s.tenant_id: %w", table, err)
		}
	}
	return nil
}

func queryPairs(db *sql.DB, query string, args ...any) ([][2]string, error) {
	rows, err := db.Query(query, args...)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var pairs [][2]string
	for rows.Next() {
		var first, second string
		if err = rows.Scan(&first, &second); err != nil {
			return nil, err
		}
		pairs = append(pairs, [2]string{first, second})
	}
	return pairs, rows.Err()
}

func quoteIdent(name string) string {
	return "`" + strings.ReplaceAll(name, "`", "``") + "`"
}