local null_ls = require("null-ls")
local helpers = require("null-ls.helpers")

local blacklint = {
    method = null_ls.methods.DIAGNOSTICS,
    filetypes = { "python" },
    -- null_ls.generator creates an async source
    -- that spawns the command with the given arguments and options
    generator = null_ls.generator({
        command = "black",
        args = { "--stdin" },
        to_stdin = true,
        from_stderr = true,
        -- choose an output format (raw, json, or line)
        format = "line",
        check_exit_code = function(code)
            return code <= 1
        end,
        -- use helpers to parse the output from string matchers,
        -- or parse it manually with a function
        on_output = helpers.diagnostics.from_patterns({
            {
                pattern = [[:(%d+):(%d+) [%w-/]+ (.*)]],
                groups = { "row", "col", "message" },
            },
            {
                pattern = [[:(%d+) [%w-/]+ (.*)]],
                groups = { "row", "message" },
            },
        }),
    }),
}

null_ls.register(blacklint)