-- f1 farm SQL helpers (Lua 5.4.6)
-- Uses project-standard MySQL connector: server_data/script/Sql_con.lua

local M = {}

local function _ensure_sql()
  if type(_G.Sql_con) == "function" then
    return true
  end
  pcall(require, "Sql_con")
  if type(_G.Sql_con) == "function" then
    return true
  end
  pcall(dofile, "server_data/script/Sql_con.lua")
  if type(_G.Sql_con) == "function" then
    return true
  end
  pcall(dofile, "../server_data/script/Sql_con.lua")
  return type(_G.Sql_con) == "function"
end

local function _to_int(v, default)
  local n = tonumber(v)
  if n == nil then
    return default or 0
  end
  if n ~= n or n == math.huge or n == -math.huge then
    return default or 0
  end
  return math.floor(n)
end

local function _exec(con, sql)
  if con == nil or type(con.execute) ~= "function" then
    return false
  end
  local ok, r1, r2 = pcall(function()
    return con:execute(sql)
  end)
  if ok and r1 ~= nil then
    return true
  end
  _G._farm_f1_sql_last_error = tostring(ok and r2 or r1)
  return false
end

local function _select1(con, sql)
  if con == nil or type(con.execute) ~= "function" then
    return nil
  end
  local ok, cur_or_val, err = pcall(function()
    return con:execute(sql)
  end)
  if not ok or cur_or_val == nil then
    _G._farm_f1_sql_last_error = tostring(ok and err or cur_or_val)
    return nil
  end
  local cur = cur_or_val
  local v = nil
  if type(cur) == "userdata" and type(cur.fetch) == "function" then
    v = cur:fetch()
    pcall(function() cur:close() end)
  end
  return v
end

function M.getCon()
  _ensure_sql()
  if type(_G.Sql_con) ~= "function" then
    return nil
  end
  return _G.Sql_con()
end

function M.ensureSchema()
  local con = M.getCon()
  if con == nil then
    return false
  end

  local role_exists = _select1(con, [[
SELECT COUNT(*) FROM information_schema.tables
WHERE table_schema = 'sm_data' AND table_name = 'farm_f1_role'
]])

  local plot_exists = _select1(con, [[
SELECT COUNT(*) FROM information_schema.tables
WHERE table_schema = 'sm_data' AND table_name = 'farm_f1_plot'
]])

  if _to_int(role_exists) < 1 or _to_int(plot_exists) < 1 then
    _G._farm_f1_sql_last_error = "farm_f1 schema missing: run server_data/script/activity/провер/Ферма/schema_f1.sql"
    return false
  end

  return true
end

-- Expose helpers
M.to_int = _to_int
M.exec = _exec
M.select1 = _select1

return M