argonaut.nvim/lua/argonaut.lua

local ArgonautConfig = {
    line_prefix = '',
    padded_braces = {},
    tail_comma = false,
    tail_comma_braces = {},
    tail_indent_braces = {},
    wrap_closing_brace = true,
    comma_first = false,
    comma_first_indent = false,
}

local function setup(opts)
    if opts then
        for key, value in pairs(opts) do
            ArgonautConfig[key] = value
        end
    end
end

local function get_cursor_pos()
    local _, row, col, _ = unpack(vim.fn.getpos('.'))
    return {row = row, col = col}
end

local function is_string_literal(pos)
    if not pos then
        pos = get_cursor_pos()
    end

    local syn_id = vim.fn.synID(pos.row, pos.col, false)
    local syn_attr = vim.fn.synIDattr(syn_id, 'name')

    return syn_attr:find('String$')
end

local function find_brace_alt(brace)
    local brace_pairs = {{'(', ')'}, {'[', ']'}, {'{', '}'}, {'<', '>'}}

    for _, brace_pair in ipairs(brace_pairs) do
        if brace_pair[1] == brace then
            return brace_pair[2], true
        elseif brace_pair[2] == brace then
            return brace_pair[1], false
        end
    end
end

local function escape_brace(brace)
    if brace == '[' or brace == ']' then
        return '\\' .. brace
    else
        return brace
    end
end

local function find_brace_range(brace)
    local brace_alt, _ = find_brace_alt(brace)
    assert(brace_alt)

    local row1, col1 = unpack(vim.fn.searchpairpos(escape_brace(brace), '', escape_brace(brace_alt), 'Wnb', is_string_literal))
    if row1 > 0 and col1 > 0 then
        local row2, col2 = unpack(vim.fn.searchpairpos(escape_brace(brace), '', escape_brace(brace_alt), 'Wcn', is_string_literal))
        if row2 > 0 and col2 > 0 then
            return {
                brace = brace,
                row1 = row1,
                col1 = col1,
                row2 = row2,
                col2 = col2
            }
        end
    end
end

local function find_all_brace_ranges(braces)
    local brace_ranges = {}
    for _, brace in ipairs(braces) do
        local brace_range = find_brace_range(brace)
        if brace_range then
            table.insert(brace_ranges, brace_range)
        end
    end

    if #brace_ranges > 0 then
        return brace_ranges
    end
end

local function find_closest_brace_range(braces)
    local cursor_pos = get_cursor_pos()
    local compare_brace_ranges = function(brace_range_1, brace_range_2)
        local row_diff1 = cursor_pos.row - brace_range_1.row1
        local row_diff2 = cursor_pos.row - brace_range_2.row1
        if row_diff1 < row_diff2 then
            return -1
        elseif row_diff1 > row_diff2 then
            return 1
        end

        local col_diff1 = cursor_pos.col - brace_range_1.col1
        local col_diff2 = cursor_pos.col - brace_range_2.col1
        if col_diff1 < col_diff2 then
            return -1
        elseif col_diff1 > col_diff2 then
            return 1
        end

        return 0
    end

    local brace_ranges = find_all_brace_ranges(braces)
    if brace_ranges then
        return vim.fn.sort(brace_ranges, compare_brace_ranges)[1]
    end
end

local function parse_brace_range(brace_range)
    local brace_range_params = {}
    local brace_range_param = ''
    local flush_brace_range_param = function()
        if #brace_range_param > 0 then
            brace_range_param, _ = brace_range_param:gsub('^%s*([%S%s]-)%s*$', '%1')
            table.insert(brace_range_params, brace_range_param)
            brace_range_param = ''
        end
    end

    local brace_stack = {}
    local update_brace_stack = function(c)
        local brace_stack_size = #brace_stack
        local brace_alt, brace_open = find_brace_alt(c)
        if brace_stack_size > 0 and brace_alt == brace_stack[brace_stack_size] and not brace_open then
            table.remove(brace_stack, brace_stack_size)
        elseif brace_alt then
            table.insert(brace_stack, c)
        end
    end

    local brace_range_elements = {}
    for row = brace_range.row1, brace_range.row2 do
        local line = vim.fn.getline(row)

        local col1 = 0
        if row == brace_range.row1 then
            col1 = brace_range.col1 + 1
        end

        local col2 = #line
        if row == brace_range.row2 then
            col2 = brace_range.col2 - 1
        end

        for i = col1, col2 do
            table.insert(brace_range_elements, {
                char = line:sub(i, i), ---@diagnostic disable-line: undefined-field
                literal = is_string_literal({row = row, col = i}),
            })
        end
    end

    if #brace_range_elements > 0 then
        for _, brace_range_element in ipairs(brace_range_elements) do
            local append = true
            if not brace_range_element.literal then
                update_brace_stack(brace_range_element.char)
                if #brace_stack == 0 and brace_range_element.char == ',' then
                    flush_brace_range_param()
                    append = false
                end
            end

            if append then
                brace_range_param = brace_range_param .. brace_range_element.char
            end
        end

        flush_brace_range_param()
    end

    for _, p in ipairs(brace_range_params) do
        print(p)
    end
end

local function reflow()
    local brace_range = find_closest_brace_range({'(', '[', '{', '<'})
    if brace_range then
        parse_brace_range(brace_range)
    end
end

return {
    reflow = reflow,
    ssetup = setup,
}