migratio-cli 0.4.4

//! CLI support library for migratio database migrations.
//!
//! This crate provides the runtime support for migration runner binaries
//! generated by `cargo-migratio`. It handles CLI argument parsing and
//! executes migration commands against the database.
//!
//! # Example
//!
//! This crate is typically used by auto-generated runner code, but can
//! also be used directly:
//!
//! ```ignore
//! use migratio_cli::{CliArgs, run_sqlite};
//! use clap::Parser;
//!
//! fn main() -> Result<(), Box<dyn std::error::Error>> {
//!     let database_url = std::env::var("DATABASE_URL")?;
//!     let migrator = my_app::migrations::get_migrator();
//!     let args = CliArgs::parse();
//!     run_sqlite(migrator, &database_url, args)
//! }
//! ```
//!
//! For PostgreSQL:
//!
//! ```ignore
//! use migratio_cli::{CliArgs, run_postgres};
//! use clap::Parser;
//!
//! fn main() -> Result<(), Box<dyn std::error::Error>> {
//!     let database_url = std::env::var("DATABASE_URL")?;
//!     let migrator = my_app::migrations::get_postgres_migrator();
//!     let args = CliArgs::parse();
//!     run_postgres(migrator, &database_url, args)
//! }
//! ```

use clap::{Parser, Subcommand};

/// CLI arguments for the migration runner.
#[derive(Parser, Debug)]
#[command(name = "migratio-runner")]
#[command(about = "Database migration runner")]
pub struct CliArgs {
    #[command(subcommand)]
    pub command: Commands,
}

/// Available migration commands for the runner binary.
#[derive(Subcommand, Debug)]
pub enum Commands {
    /// Show current migration status (requires database)
    Status,
    /// Run pending migrations (requires database)
    Upgrade {
        /// Target version (default: latest)
        #[arg(long)]
        to: Option<u32>,
    },
    /// Rollback migrations (requires database)
    Downgrade {
        /// Target version to rollback to
        #[arg(long)]
        to: u32,
    },
    /// Show migration history (requires database)
    History,
    /// Preview pending migrations without running them (requires database)
    Preview,
    /// List all migrations defined in the migrator (no database required)
    List,
    /// Show the resulting schema after applying all migrations (sqlite only; no database required)
    Schema {
        /// Write the schema to a file instead of stdout
        #[arg(short, long)]
        output: Option<std::path::PathBuf>,
    },
}

#[cfg(feature = "sqlite")]
pub use sqlite::{run_sqlite, schema_sqlite};

#[cfg(feature = "sqlite")]
mod sqlite {
    use super::{CliArgs, Commands};
    use migratio::sqlite::SqliteMigrator;
    use rusqlite::Connection;

    /// Run the CLI with a SQLite migrator.
    ///
    /// This function handles all CLI commands for SQLite databases.
    ///
    /// # Arguments
    ///
    /// * `migrator` - The configured SQLite migrator
    /// * `database_url` - Path to the SQLite database file
    /// * `args` - Parsed CLI arguments
    ///
    /// # Returns
    ///
    /// Returns `Ok(())` on success, or an error if the operation fails.
    pub fn run_sqlite(
        migrator: SqliteMigrator,
        database_url: &str,
        args: CliArgs,
    ) -> Result<(), Box<dyn std::error::Error>> {
        // Schema doesn't need the configured database at all - it runs migrations
        // against a throwaway in-memory database instead.
        let command = match args.command {
            Commands::Schema { output } => return schema_sqlite(migrator, output),
            command => command,
        };

        // Check if the database file exists before opening
        // (SQLite will create a new file if it doesn't exist, which we don't want)
        if !std::path::Path::new(database_url).exists() {
            return Err(format!(
                "Database file not found: {}\n\nTo create a new database, first create the file manually or use your application's initialization logic.",
                database_url
            ).into());
        }

        let mut conn = Connection::open(database_url)?;

        match command {
            Commands::Status => {
                let version = migrator.get_current_version(&mut conn)?;
                let pending = migrator.preview_upgrade(&mut conn)?;
                println!("Current version: {}", version);
                println!("Pending migrations: {}", pending.len());
                for m in pending {
                    println!("  - {} (v{})", m.name(), m.version());
                }
            }
            Commands::Upgrade { to } => {
                let report = match to {
                    Some(target) => migrator.upgrade_to(&mut conn, target)?,
                    None => migrator.upgrade(&mut conn)?,
                };
                if report.migrations_run.is_empty() {
                    println!("No migrations to run.");
                } else {
                    println!("Migrations run: {:?}", report.migrations_run);
                }
            }
            Commands::Downgrade { to } => {
                let report = migrator.downgrade(&mut conn, to)?;
                if report.migrations_run.is_empty() {
                    println!("No migrations to roll back.");
                } else {
                    println!("Migrations rolled back: {:?}", report.migrations_run);
                }
            }
            Commands::History => {
                let history = migrator.get_migration_history(&mut conn)?;
                if history.is_empty() {
                    println!("No migrations have been applied yet.");
                } else {
                    println!("Migration history:");
                    for entry in history {
                        println!(
                            "  v{}: {} [{}] (applied {})",
                            entry.version, entry.name, entry.migration_type, entry.applied_at
                        );
                    }
                }
            }
            Commands::Preview => {
                let pending = migrator.preview_upgrade(&mut conn)?;
                if pending.is_empty() {
                    println!("No pending migrations.");
                } else {
                    println!("Pending migrations:");
                    for m in pending {
                        println!("  - {} (v{})", m.name(), m.version());
                        if let Some(desc) = m.description() {
                            println!("    {}", desc);
                        }
                    }
                }
            }
            Commands::List => {
                // This command is handled before run_sqlite is called.
                // If we get here, something went wrong.
                unreachable!("List command should be handled before run_sqlite");
            }
            Commands::Schema { .. } => {
                unreachable!("Schema command is handled before run_sqlite reaches this match")
            }
        }

        Ok(())
    }

    /// Renders the schema DDL as a string. Pure — no I/O beyond reading the given connection.
    fn render_schema(conn: &Connection, migrations_applied: usize) -> Result<String, rusqlite::Error> {
        let mut stmt = conn.prepare(
            "SELECT sql FROM sqlite_master \
             WHERE sql IS NOT NULL AND name NOT LIKE 'sqlite_%' AND name != '_migratio_version_' \
             ORDER BY CASE type WHEN 'table' THEN 0 WHEN 'index' THEN 1 WHEN 'view' THEN 2 WHEN 'trigger' THEN 3 ELSE 4 END, name",
        )?;
        let statements: Vec<String> = stmt
            .query_map([], |row| row.get(0))?
            .collect::<Result<Vec<_>, _>>()?;

        let mut output = format!(
            "-- Schema generated by migratio ({} migrations applied)\n\
             -- Note: the _migratio_version_ bookkeeping table is excluded.\n\n",
            migrations_applied
        );
        output.push_str(
            &statements
                .iter()
                .map(|sql| format!("{};\n", sql))
                .collect::<Vec<_>>()
                .join("\n"),
        );

        Ok(output)
    }

    /// Runs all migrations against an in-memory sqlite db and outputs the resulting schema.
    pub fn schema_sqlite(
        migrator: SqliteMigrator,
        output: Option<std::path::PathBuf>,
    ) -> Result<(), Box<dyn std::error::Error>> {
        let mut conn = Connection::open_in_memory()?;
        let report = migrator.upgrade(&mut conn)?;
        let schema = render_schema(&conn, report.migrations_run.len())?;
        match output {
            Some(path) => std::fs::write(path, schema)?,
            None => println!("{}", schema),
        }
        Ok(())
    }

    #[cfg(test)]
    mod tests {
        use super::*;
        use migratio::sql_migration;

        #[test]
        fn render_schema_single_migration() {
            sql_migration!(CreateUsers, 1, "Create users",
                up: "CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)",
                down: "DROP TABLE users"
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateUsers)]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            assert!(schema.contains("CREATE TABLE users"));
            assert!(schema.contains(';'));
        }

        #[test]
        fn render_schema_multiple_migrations() {
            sql_migration!(CreateUsers, 1, "Create users",
                up: "CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)",
                down: "DROP TABLE users"
            );
            sql_migration!(CreatePosts, 2, "Create posts",
                up: [
                    "CREATE TABLE posts (id INTEGER PRIMARY KEY, user_id INTEGER, title TEXT)",
                    "CREATE INDEX idx_posts_user ON posts(user_id)"
                ],
                down: [
                    "DROP INDEX idx_posts_user",
                    "DROP TABLE posts"
                ]
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateUsers), Box::new(CreatePosts)]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            assert!(schema.contains("CREATE TABLE users"));
            assert!(schema.contains("CREATE TABLE posts"));
            assert!(schema.contains("CREATE INDEX idx_posts_user"));
        }

        #[test]
        fn render_schema_orders_tables_then_index_then_view_then_trigger() {
            sql_migration!(CreateAll, 1, "Create everything, scrambled",
                up: [
                    "CREATE TABLE b (id INTEGER PRIMARY KEY)",
                    "CREATE TABLE a (id INTEGER PRIMARY KEY)",
                    "CREATE VIEW v AS SELECT * FROM a",
                    "CREATE INDEX idx_b ON b(id)",
                    "CREATE TRIGGER trg AFTER INSERT ON a BEGIN SELECT 1; END"
                ],
                down: [
                    "DROP TRIGGER trg",
                    "DROP INDEX idx_b",
                    "DROP VIEW v",
                    "DROP TABLE a",
                    "DROP TABLE b"
                ]
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateAll)]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            let a = schema.find("CREATE TABLE a").unwrap();
            let b = schema.find("CREATE TABLE b").unwrap();
            let idx_b = schema.find("CREATE INDEX idx_b").unwrap();
            let v = schema.find("CREATE VIEW v").unwrap();
            let trg = schema.find("CREATE TRIGGER trg").unwrap();

            assert!(a < b, "table a should come before table b");
            assert!(b < idx_b, "tables should come before indexes");
            assert!(idx_b < v, "indexes should come before views");
            assert!(v < trg, "views should come before triggers");
        }

        #[test]
        fn render_schema_excludes_migratio_bookkeeping_table() {
            sql_migration!(CreateUsers, 1, "Create users",
                up: "CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)",
                down: "DROP TABLE users"
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateUsers)]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            assert!(!schema.contains("CREATE TABLE _migratio_version_"));
        }

        #[test]
        fn render_schema_excludes_sqlite_internal_tables() {
            sql_migration!(CreateUsers, 1, "Create users with autoincrement",
                up: "CREATE TABLE users (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT)",
                down: "DROP TABLE users"
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateUsers)]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            assert!(!schema.contains("sqlite_sequence"));
        }

        #[test]
        fn render_schema_empty_migrator() {
            let migrator = SqliteMigrator::new(vec![]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            assert!(schema.contains("0 migrations applied"));
            assert!(!schema.contains("CREATE TABLE"));
        }

        #[test]
        fn render_schema_banner_reports_migration_count() {
            sql_migration!(M1, 1, "one", up: "CREATE TABLE t1 (id INTEGER PRIMARY KEY)", down: "DROP TABLE t1");
            sql_migration!(M2, 2, "two", up: "CREATE TABLE t2 (id INTEGER PRIMARY KEY)", down: "DROP TABLE t2");
            sql_migration!(M3, 3, "three", up: "CREATE TABLE t3 (id INTEGER PRIMARY KEY)", down: "DROP TABLE t3");

            let migrator =
                SqliteMigrator::new(vec![Box::new(M1), Box::new(M2), Box::new(M3)]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            assert!(schema.contains("3 migrations applied"));
        }

        #[test]
        fn render_schema_banner_notes_bookkeeping_table_exclusion() {
            let migrator = SqliteMigrator::new(vec![]);
            let mut conn = Connection::open_in_memory().unwrap();
            let report = migrator.upgrade(&mut conn).unwrap();

            let schema = render_schema(&conn, report.migrations_run.len()).unwrap();

            assert!(schema.contains("_migratio_version_"));
        }

        #[test]
        fn schema_sqlite_writes_to_output_file() {
            sql_migration!(CreateUsers, 1, "Create users",
                up: "CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)",
                down: "DROP TABLE users"
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateUsers)]);
            let path = std::env::temp_dir()
                .join("migratio_cli_test_schema_sqlite_writes_to_output_file.sql");

            let result = schema_sqlite(migrator, Some(path.clone()));

            assert!(result.is_ok());
            let contents = std::fs::read_to_string(&path).unwrap();
            assert!(contents.contains("CREATE TABLE users"));

            std::fs::remove_file(&path).ok();
        }

        #[test]
        fn schema_sqlite_overwrites_existing_file_silently() {
            sql_migration!(CreateUsers, 1, "Create users",
                up: "CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)",
                down: "DROP TABLE users"
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateUsers)]);
            let path = std::env::temp_dir()
                .join("migratio_cli_test_schema_sqlite_overwrites_existing_file_silently.sql");
            std::fs::write(&path, "old content").unwrap();

            let result = schema_sqlite(migrator, Some(path.clone()));

            assert!(result.is_ok());
            let contents = std::fs::read_to_string(&path).unwrap();
            assert!(!contents.contains("old content"));
            assert!(contents.contains("CREATE TABLE users"));

            std::fs::remove_file(&path).ok();
        }

        #[test]
        fn schema_sqlite_prints_to_stdout_when_no_output_given() {
            sql_migration!(CreateUsers, 1, "Create users",
                up: "CREATE TABLE users (id INTEGER PRIMARY KEY, name TEXT)",
                down: "DROP TABLE users"
            );

            let migrator = SqliteMigrator::new(vec![Box::new(CreateUsers)]);

            let result = schema_sqlite(migrator, None);

            assert!(result.is_ok());
        }
    }
}

#[cfg(feature = "mysql")]
pub use mysql_support::run_mysql;

#[cfg(feature = "postgres")]
pub use postgres_support::run_postgres;

#[cfg(feature = "mysql")]
mod mysql_support {
    use super::{CliArgs, Commands};
    use migratio::mysql::MysqlMigrator;
    use mysql::{Conn, Opts};

    /// Run the CLI with a MySQL migrator.
    ///
    /// This function handles all CLI commands for MySQL databases.
    ///
    /// # Arguments
    ///
    /// * `migrator` - The configured MySQL migrator
    /// * `database_url` - MySQL connection URL
    /// * `args` - Parsed CLI arguments
    ///
    /// # Returns
    ///
    /// Returns `Ok(())` on success, or an error if the operation fails.
    pub fn run_mysql(
        migrator: MysqlMigrator,
        database_url: &str,
        args: CliArgs,
    ) -> Result<(), Box<dyn std::error::Error>> {
        if let Commands::Schema { .. } = &args.command {
            return Err("the `schema` command is only supported for sqlite databases".into());
        }

        let opts = Opts::from_url(database_url)?;
        let mut conn = Conn::new(opts)?;

        match args.command {
            Commands::Status => {
                let version = migrator.get_current_version(&mut conn)?;
                let pending = migrator.preview_upgrade(&mut conn)?;
                println!("Current version: {}", version);
                println!("Pending migrations: {}", pending.len());
                for m in pending {
                    println!("  - {} (v{})", m.name(), m.version());
                }
            }
            Commands::Upgrade { to } => {
                let report = match to {
                    Some(target) => migrator.upgrade_to(&mut conn, target)?,
                    None => migrator.upgrade(&mut conn)?,
                };
                if report.migrations_run.is_empty() {
                    println!("No migrations to run.");
                } else {
                    println!("Migrations run: {:?}", report.migrations_run);
                }
            }
            Commands::Downgrade { to } => {
                let report = migrator.downgrade(&mut conn, to)?;
                if report.migrations_run.is_empty() {
                    println!("No migrations to roll back.");
                } else {
                    println!("Migrations rolled back: {:?}", report.migrations_run);
                }
            }
            Commands::History => {
                let history = migrator.get_migration_history(&mut conn)?;
                if history.is_empty() {
                    println!("No migrations have been applied yet.");
                } else {
                    println!("Migration history:");
                    for entry in history {
                        println!(
                            "  v{}: {} [{}] (applied {})",
                            entry.version, entry.name, entry.migration_type, entry.applied_at
                        );
                    }
                }
            }
            Commands::Preview => {
                let pending = migrator.preview_upgrade(&mut conn)?;
                if pending.is_empty() {
                    println!("No pending migrations.");
                } else {
                    println!("Pending migrations:");
                    for m in pending {
                        println!("  - {} (v{})", m.name(), m.version());
                        if let Some(desc) = m.description() {
                            println!("    {}", desc);
                        }
                    }
                }
            }
            Commands::List => {
                // This command is handled before run_mysql is called.
                // If we get here, something went wrong.
                unreachable!("List command should be handled before run_mysql");
            }
            Commands::Schema { .. } => {
                unreachable!("Schema command is rejected before run_mysql reaches this match")
            }
        }

        Ok(())
    }
}

#[cfg(feature = "postgres")]
mod postgres_support {
    use super::{CliArgs, Commands};
    use migratio::postgres::PostgresMigrator;
    use postgres::{Client, NoTls};

    /// Run the CLI with a PostgreSQL migrator.
    ///
    /// This function handles all CLI commands for PostgreSQL databases.
    ///
    /// # Arguments
    ///
    /// * `migrator` - The configured PostgreSQL migrator
    /// * `database_url` - PostgreSQL connection URL
    /// * `args` - Parsed CLI arguments
    ///
    /// # Returns
    ///
    /// Returns `Ok(())` on success, or an error if the operation fails.
    pub fn run_postgres(
        migrator: PostgresMigrator,
        database_url: &str,
        args: CliArgs,
    ) -> Result<(), Box<dyn std::error::Error>> {
        if let Commands::Schema { .. } = &args.command {
            return Err("the `schema` command is only supported for sqlite databases".into());
        }

        let mut client = Client::connect(database_url, NoTls)?;

        match args.command {
            Commands::Status => {
                let version = migrator.get_current_version(&mut client)?;
                let pending = migrator.preview_upgrade(&mut client)?;
                println!("Current version: {}", version);
                println!("Pending migrations: {}", pending.len());
                for m in pending {
                    println!("  - {} (v{})", m.name(), m.version());
                }
            }
            Commands::Upgrade { to } => {
                let report = match to {
                    Some(target) => migrator.upgrade_to(&mut client, target)?,
                    None => migrator.upgrade(&mut client)?,
                };
                if report.migrations_run.is_empty() {
                    println!("No migrations to run.");
                } else {
                    println!("Migrations run: {:?}", report.migrations_run);
                }
            }
            Commands::Downgrade { to } => {
                let report = migrator.downgrade(&mut client, to)?;
                if report.migrations_run.is_empty() {
                    println!("No migrations to roll back.");
                } else {
                    println!("Migrations rolled back: {:?}", report.migrations_run);
                }
            }
            Commands::History => {
                let history = migrator.get_migration_history(&mut client)?;
                if history.is_empty() {
                    println!("No migrations have been applied yet.");
                } else {
                    println!("Migration history:");
                    for entry in history {
                        println!(
                            "  v{}: {} [{}] (applied {})",
                            entry.version, entry.name, entry.migration_type, entry.applied_at
                        );
                    }
                }
            }
            Commands::Preview => {
                let pending = migrator.preview_upgrade(&mut client)?;
                if pending.is_empty() {
                    println!("No pending migrations.");
                } else {
                    println!("Pending migrations:");
                    for m in pending {
                        println!("  - {} (v{})", m.name(), m.version());
                        if let Some(desc) = m.description() {
                            println!("    {}", desc);
                        }
                    }
                }
            }
            Commands::List => {
                // This command is handled before run_postgres is called.
                // If we get here, something went wrong.
                unreachable!("List command should be handled before run_postgres");
            }
            Commands::Schema { .. } => {
                unreachable!("Schema command is rejected before run_postgres reaches this match")
            }
        }

        Ok(())
    }
}