import { createClient, Client } from "@libsql/client";
import dotenv from "dotenv";
import fs from "fs";
import path from "path";

dotenv.config({ path: process.env.DOTENV_PATH || ".env" });

// =============================================================================
// Exported utility functions for testing
// =============================================================================

/** Get the full migration SQL string */
export function getMigrationSQL(): string {
  return `
    CREATE TABLE IF NOT EXISTS users (
      id integer PRIMARY KEY AUTOINCREMENT,
      username text NOT NULL UNIQUE,
      password_hash text,
      avatar_url text,
      auth_provider text NOT NULL DEFAULT 'local',
      oidc_subject text,
      is_active integer NOT NULL DEFAULT 1,
      last_login_at integer,
      created_at integer NOT NULL DEFAULT (strftime('%s','now')),
      updated_at integer NOT NULL DEFAULT (strftime('%s','now'))
    );

    CREATE TABLE IF NOT EXISTS medications (
      id integer PRIMARY KEY AUTOINCREMENT,
      user_id integer NOT NULL,
      name text NOT NULL,
      generic_name text,
      taken_by_json text NOT NULL DEFAULT '[]',
      pack_count integer NOT NULL DEFAULT 1,
      blisters_per_pack integer NOT NULL DEFAULT 1,
      pills_per_blister integer NOT NULL DEFAULT 1,
      loose_tablets integer NOT NULL DEFAULT 0,
      pill_weight_mg integer,
      usage_json text NOT NULL DEFAULT '[]',
      every_json text NOT NULL DEFAULT '[]',
      start_json text NOT NULL DEFAULT '[]',
      image_url text,
      expiry_date text,
      notes text,
      intake_reminders_enabled integer NOT NULL DEFAULT 0,
      updated_at integer NOT NULL DEFAULT (strftime('%s','now')),
      FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
    );

    CREATE TABLE IF NOT EXISTS user_settings (
      id integer PRIMARY KEY AUTOINCREMENT,
      user_id integer NOT NULL UNIQUE,
      email_enabled integer NOT NULL DEFAULT 0,
      notification_email text,
      email_stock_reminders integer NOT NULL DEFAULT 1,
      email_intake_reminders integer NOT NULL DEFAULT 1,
      shoutrrr_enabled integer NOT NULL DEFAULT 0,
      shoutrrr_url text,
      shoutrrr_stock_reminders integer NOT NULL DEFAULT 1,
      shoutrrr_intake_reminders integer NOT NULL DEFAULT 1,
      reminder_days_before integer NOT NULL DEFAULT 7,
      repeat_daily_reminders integer NOT NULL DEFAULT 0,
      low_stock_days integer NOT NULL DEFAULT 30,
      normal_stock_days integer NOT NULL DEFAULT 90,
      high_stock_days integer NOT NULL DEFAULT 180,
      language text NOT NULL DEFAULT 'en',
      stock_calculation_mode text NOT NULL DEFAULT 'automatic',
      last_auto_email_sent text,
      last_notification_type text,
      last_notification_channel text,
      updated_at integer NOT NULL DEFAULT (strftime('%s','now')),
      FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
    );

    CREATE TABLE IF NOT EXISTS refresh_tokens (
      id integer PRIMARY KEY AUTOINCREMENT,
      user_id integer NOT NULL,
      token_id text NOT NULL UNIQUE,
      expires_at integer NOT NULL,
      rotated_at integer,
      revoked integer NOT NULL DEFAULT 0,
      created_at integer NOT NULL DEFAULT (strftime('%s','now')),
      FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
    );

    CREATE TABLE IF NOT EXISTS share_tokens (
      id integer PRIMARY KEY AUTOINCREMENT,
      user_id integer NOT NULL,
      token text NOT NULL UNIQUE,
      taken_by text NOT NULL,
      schedule_days integer NOT NULL DEFAULT 30,
      created_at integer NOT NULL DEFAULT (strftime('%s','now')),
      expires_at integer,
      FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
    );

    CREATE TABLE IF NOT EXISTS dose_tracking (
      id integer PRIMARY KEY AUTOINCREMENT,
      user_id integer NOT NULL,
      dose_id text NOT NULL,
      taken_at integer NOT NULL DEFAULT (strftime('%s','now')),
      marked_by text,
      FOREIGN KEY (user_id) REFERENCES users(id) ON DELETE CASCADE
    );
  `;
}

/** Split SQL string into individual statements */
export function splitSQLStatements(sql: string): string[] {
  return sql.split(';').filter(s => s.trim().length > 0);
}

/** Execute migration statements on a client */
export async function executeMigration(client: Client): Promise<{ success: boolean; executed: number; errors: string[] }> {
  const sql = getMigrationSQL();
  const statements = splitSQLStatements(sql);
  const errors: string[] = [];
  let executed = 0;

  for (const stmt of statements) {
    try {
      await client.execute(stmt);
      executed++;
    } catch (err: any) {
      errors.push(err.message);
    }
  }

  return { success: errors.length === 0, executed, errors };
}

/** Get a preview of statement (first N characters) */
export function getStatementPreview(stmt: string, maxLength: number = 50): string {
  const trimmed = stmt.trim();
  if (trimmed.length <= maxLength) {
    return trimmed;
  }
  return trimmed.substring(0, maxLength) + "...";
}

// =============================================================================
// CLI execution (only runs when called directly)
// =============================================================================

const url = "file:./data/medassist-ng.db";

async function main() {
  console.log("Starting database setup...");
  console.log("Database URL:", url);
  
  const client = createClient({ url });
  
  const sql = getMigrationSQL();
  const statements = splitSQLStatements(sql);
  
  for (const stmt of statements) {
    console.log("Executing:", getStatementPreview(stmt));
    await client.execute(stmt);
  }

  console.log("Database setup complete!");
  process.exit(0);
}

// Only run main() if this file is executed directly (not imported)
const isMainModule = import.meta.url === `file://${process.argv[1]}`;
if (isMainModule) {
  main().catch((err) => {
    console.error("Migration failed:", err);
    process.exit(1);
  });
}