local job_id, job_buffer

local function job_exit(jobId, exit_code, _)
    job_id = nil
    print("job done!")
end

local function has_buffer()
    return job_buffer and vim.fn.buflisted(job_buffer) == 1
end

local function get_build_cmd()
    for path, type in vim.fs.dir(vim.fn.getcwd(), nil)
        do
        if (path == "build.zig") then
            return "zig build"
        end
        if (path == "build.bat" or path == "build.sh") then
            if (vim.loop.os_uname().sysname == "Windows_NT") then
                -- TODO(twig): if I move to llvm this should work, right now cl doesn't work because nvim spawns a command prompt that doesn't have vcvars in it (nor does it have my stuff)
                return "build.bat"
            else
                -- TODO(twig): this is untested!
                return "./build.sh"
            end
        end
    end
    return ""
end

function save_all_and_build()
    if job_id then
        print("Job processing")
        return
    end

    local opts = {}
    vim.api.nvim_exec('wa', opts)

    if not has_buffer() then
        job_buffer = vim.api.nvim_create_buf(true, true)
    end
    local job_window = vim.fn.bufwinnr(job_buffer)
    if job_window ~= -1 then
        vim.cmd(job_window .. ' wincmd w')
    else
        vim.cmd('buffer ' .. job_buffer)
    end
    vim.api.nvim_buf_set_option(job_buffer, 'filetype', 'build')
    vim.api.nvim_buf_set_option(job_buffer, 'modified', false)
    -- THis looks at files in the cwd and decides if there is something to build (build.zig for zig, build.bat/.sh for c++)
    local build_cmd = get_build_cmd()
    job_id = vim.fn.termopen(build_cmd, {on_exit = job_exit})
    vim.api.nvim_buf_set_name(job_buffer, '[build]')
end