package main

import (
	"database/sql"
)

type migration struct {
	up   string
	down string
}

var migrations = []migration{
	migration{
		up: `CREATE TABLE IF NOT EXISTS configs (
			key string NOT NULL,
			value string NOT NULL
		);
		CREATE UNIQUE INDEX IF NOT EXISTS unique_configs_key ON configs (key);
		`,
		down: `DROP TABLE IF EXISTS configs`,
	},
	migration{
		up: `CREATE TABLE IF NOT EXISTS peers (
			mhash string NOT NULL,
			status string NOT NULL
		);
		CREATE UNIQUE INDEX IF NOT EXISTS unique_peers_mhash ON peers (mhash);
		`,
		down: `DROP TABLE IF EXISTS peers`,
	},
	migration{
		up: `CREATE TABLE IF NOT EXISTS messages (
			id        INTEGER PRIMARY KEY AUTOINCREMENT,
			author    string NOT NULL,
			depth     int    NOT NULL,
			kind      string NOT NULL,
			prev      string NOT NULL,
			signature string NOT NULL,
			mhash     string NOT NULL
		);
		`,
		down: `DROP TABLE IF EXISTS messages`,
	},
	migration{
		up: `CREATE TABLE IF NOT EXISTS body_items (
			parent  int    NOT NULL,
			key     string NOT NULL,
			value   string NOT NULL,
			rank    int    NOT NULL,
			FOREIGN KEY(parent) REFERENCES messages(id)
		);
		`,
		down: `DROP TABLE IF EXISTS body_items`,
	},
}

func migrateUp(db *sql.DB) {
	tx, err := db.Begin()

	check(err, "Failed to start transaction: %s", err)

	for i, migration := range migrations {
		_, err := tx.Exec(migration.up)
		check(err, "Migration failure(%d): %s", i, err)
	}
	err3 := tx.Commit()
	check(err3, "Transaction commit failure: %s", err3)
}