module embedfs

import os

@[params]
pub struct EmbedFsParams {
pub:
	module_name      string = 'main'        // name of the generated V module.
	const_name       string = 'embed_files' // name of the constant that will store the embedded data.
	const_public     bool   // if true make the const public.
	key_path_prefix  string // path prefix for all embedded files, will be added to data map key.
	file_path_prefix string // path prefix for files used in $embed_file() call in generated file.
	compression      bool   // add zlib compression flag to $embed_file() call in generated file.
	notice           string = 'This file is generated by embedfs module, DO NOT EDIT!'
}

@[params]
pub struct GenerateParams {
	EmbedFsParams
pub:
	ignore []string // glob expressions for files that should not be embedded.
}

// generate generates the V code that embeds the contents of directory `dir`.
pub fn generate(dir string, params GenerateParams) !string {
	files := collect_files(dir, params.ignore)
	return generate_with(files, params.EmbedFsParams)!
}

// generate_with generates the V code that embeds the files listed in `paths`.
pub fn generate_with(paths []string, params EmbedFsParams) !string {
	module_name := params.module_name
	const_name := params.const_name
	const_public := params.const_public
	compression := params.compression
	notice := params.notice
	skip_notice := params.notice == ''
	mut files := map[string]string{}
	for file in paths {
		file_path := if params.file_path_prefix == '' {
			file
		} else {
			os.join_path_single(params.file_path_prefix, file)
		}
		files[os.join_path_single(params.key_path_prefix, file)] = file_path
	}
	result := $tmpl('embedfs.template')
	return result
}

fn collect_files(path string, ignore []string) []string {
	mut file_list := &[]string{}
	os.walk(path, fn [mut file_list, ignore] (file string) {
		for globexpr in ignore {
			if file.match_glob(globexpr) {
				return
			}
		}
		file_list << file
	})
	return *file_list
}