package repository

import (
	"database/sql"
	"os"
	"path/filepath"

	_ "github.com/mattn/go-sqlite3"
)

func NewDB(dbPath string) (*sql.DB, error) {
	dir := filepath.Dir(dbPath)
	if err := os.MkdirAll(dir, 0755); err != nil {
		return nil, err
	}

	db, err := sql.Open("sqlite3", dbPath+"?_journal_mode=WAL")
	if err != nil {
		return nil, err
	}

	if err := initSchema(db); err != nil {
		db.Close()
		return nil, err
	}

	return db, nil
}

func initSchema(db *sql.DB) error {
	schema := `
	CREATE TABLE IF NOT EXISTS devices (
		id TEXT PRIMARY KEY,
		hostname TEXT NOT NULL,
		os TEXT NOT NULL,
		ip TEXT NOT NULL,
		registered_at DATETIME NOT NULL,
		last_report_at DATETIME NOT NULL,
		status TEXT NOT NULL DEFAULT 'offline'
	);

	CREATE TABLE IF NOT EXISTS metrics (
		id INTEGER PRIMARY KEY AUTOINCREMENT,
		device_id TEXT NOT NULL,
		timestamp DATETIME NOT NULL,
		cpu_usage REAL,
		cpu_temperature REAL,
		cpu_core_usage TEXT,
		memory_total INTEGER,
		memory_used INTEGER,
		memory_usage REAL,
		gpu_usage REAL,
		gpu_temperature REAL,
		gpu_memory_total INTEGER,
		gpu_memory_used INTEGER,
		gpu_name TEXT,
		network_interfaces TEXT,
		disks TEXT,
		power_status TEXT,
		battery_level INTEGER,
		power_source TEXT,
		FOREIGN KEY (device_id) REFERENCES devices(id)
	);

	CREATE INDEX IF NOT EXISTS idx_metrics_device_time ON metrics(device_id, timestamp);

	CREATE TABLE IF NOT EXISTS alert_rules (
		id TEXT PRIMARY KEY,
		device_id TEXT NOT NULL,
		metric TEXT NOT NULL,
		operator TEXT NOT NULL,
		threshold REAL NOT NULL,
		duration INTEGER NOT NULL DEFAULT 0,
		created_at DATETIME NOT NULL,
		FOREIGN KEY (device_id) REFERENCES devices(id)
	);

	CREATE TABLE IF NOT EXISTS alerts (
		id TEXT PRIMARY KEY,
		device_id TEXT NOT NULL,
		rule_id TEXT NOT NULL,
		metric TEXT NOT NULL,
		value REAL NOT NULL,
		message TEXT NOT NULL,
		status TEXT NOT NULL DEFAULT 'active',
		created_at DATETIME NOT NULL,
		resolved_at DATETIME,
		FOREIGN KEY (device_id) REFERENCES devices(id),
		FOREIGN KEY (rule_id) REFERENCES alert_rules(id)
	);
	`
	_, err := db.Exec(schema)
	return err
}