import symbol:*
import tree:*
import vector:*
import queue:*
import map:*
import util:*
import string:*
import mem:*
import io:*
import ast_nodes:*
import ast_transformation:*
import parser:*
import thread:*

obj importer (Object) {
    var parsers: vector<parser>
    var ast_pass: ast_transformation
    var name_ast_map: map<string, pair<*tree<symbol>,*ast_node>>
    var import_paths: vector<string>
    fun construct(parsersIn: ref vector<parser>, ast_passIn: ref ast_transformation, import_paths_in: vector<string>): *importer {
        parsers.copy_construct(&parsersIn)
        ast_pass.copy_construct(&ast_passIn)
        name_ast_map.construct()
        import_paths.copy_construct(&import_paths_in)
        return this
    }
    fun copy_construct(old: *importer) {
        parsers.copy_construct(&old->parsers)
        ast_pass.copy_construct(&old->ast_pass)
        name_ast_map.copy_construct(&old->name_ast_map)
        import_paths.copy_construct(&old->import_paths)
    }
    fun operator=(old: ref importer) {
        destruct()
        copy_construct(&old)
    }
    fun destruct() {
        parsers.destruct()
        ast_pass.destruct()
        name_ast_map.destruct()
        import_paths.destruct()
    }
    fun import(file_name: string) {
        // lambda closes over our fix-up list
        var imports_to_fix = vector<*ast_node>()
        var import_first_pass = fun(file_name_idx: pair<string,int>) {
            var file_name = file_name_idx.first
            var file = string()
            import_paths.for_each(fun(path: string) {
                if (file_exists(path + file_name)) {
                    file = read_file(path + file_name)
                } else {
                }
            })
            printerr(file_name + ", ")
            var parse_tree = parsers[file_name_idx.second].parse_input(file, file_name)
            trim(parse_tree)
            var ast_and_imports = ast_pass.first_pass(file_name, parse_tree, this)
            imports_to_fix += ast_and_imports.second
            name_ast_map[file_name] = make_pair(parse_tree, ast_and_imports.first)
        }
        printlnerr("**First Pass**")
        printerr("parsing: ")
        import_first_pass(make_pair(file_name,0))
        for (var i = 0; i < imports_to_fix.size; i++;) {
            /*println(string("iteration of imports to fix: ") + i)*/
            var threads = vector<*ulong>()
            var num_threads = min(imports_to_fix.size - i, parsers.size)
            for (var j = i; j < i+num_threads; j++;) {
                var import_name = imports_to_fix[j]->import.name
                var file_name = import_name + ".krak"
                if (!name_ast_map.contains_key(file_name)) {
                    /*import_first_pass(file_name)*/
                    /*join(run(import_first_pass, file_name))*/
                    if (num_threads > 1)
                        threads.add(run(import_first_pass, make_pair(file_name, j-i)))
                    else
                        import_first_pass(make_pair(file_name,0))
                } else {
                    threads.add(null<ulong>())
                }
            }
            /*println(string("iteration of imports to fix: ") + i + " made")*/
            for (var j = i; j < i+num_threads; j++;) {
                if (num_threads > 1) {
                    if (threads[j-i])
                        join(threads[j-i])
                }
                var im = imports_to_fix[j]
                var import_name = im->import.name
                var file_name = import_name + ".krak"
                im->import.translation_unit = name_ast_map[file_name].second
                add_to_scope(import_name, im->import.translation_unit, im->import.containing_translation_unit)
            }
            /*println(string("iteration of imports to fix: ") + i + " done")*/
            i += num_threads-1
        }
        printlnerr()
        printlnerr("**Second Pass**")
        name_ast_map.for_each(fun(name: string, tree_pair: pair<*tree<symbol>, *ast_node>) ast_pass.second_pass(tree_pair.first, tree_pair.second);)
        printlnerr("**Third Pass**")
        name_ast_map.for_each(fun(name: string, tree_pair: pair<*tree<symbol>, *ast_node>) ast_pass.third_pass(tree_pair.first, tree_pair.second);)
        // this needs to be modified to do chaotic iteration on instantiating template classes, based on what I see in the C++ version
        printlnerr("**Fourth Pass**")
        name_ast_map.for_each(fun(name: string, tree_pair: pair<*tree<symbol>, *ast_node>) ast_pass.fourth_pass(tree_pair.first, tree_pair.second);)
    }
    fun trim(parse_tree: *tree<symbol>) {
        remove_node(symbol("$NULL$", false), parse_tree)
	    remove_node(symbol("WS", false), parse_tree)
        // the terminals have " around them, which we have to escape
	    remove_node(symbol("\"\\(\"", true), parse_tree)
	    remove_node(symbol("\"\\)\"", true), parse_tree)
        remove_node(symbol("\"template\"", true), parse_tree)
        remove_node(symbol("\"return\"", true), parse_tree)
        remove_node(symbol("\"defer\"", true), parse_tree)
        remove_node(symbol("\";\"", true), parse_tree)
        remove_node(symbol("line_end", false), parse_tree)
        remove_node(symbol("\"{\"", true), parse_tree)
        remove_node(symbol("\"}\"", true), parse_tree)
        remove_node(symbol("\"(\"", true), parse_tree)
        remove_node(symbol("\")\"", true), parse_tree)
        remove_node(symbol("\"if\"", true), parse_tree)
        remove_node(symbol("\"while\"", true), parse_tree)
        remove_node(symbol("\"__if_comp__\"", true), parse_tree)
        remove_node(symbol("\"comp_simple_passthrough\"", true), parse_tree)
        /*remove_node(symbol("obj_nonterm", false), parse_tree)*/
        remove_node(symbol("adt_nonterm", false), parse_tree)

        collapse_node(symbol("case_statement_list", false), parse_tree)
        collapse_node(symbol("opt_param_assign_list", false), parse_tree)
        collapse_node(symbol("param_assign_list", false), parse_tree)
        collapse_node(symbol("opt_typed_parameter_list", false), parse_tree)
        collapse_node(symbol("opt_parameter_list", false), parse_tree)
        collapse_node(symbol("intrinsic_parameter_list", false), parse_tree)
        collapse_node(symbol("identifier_list", false), parse_tree)
        collapse_node(symbol("adt_option_list", false), parse_tree)
        collapse_node(symbol("statement_list", false), parse_tree)
        collapse_node(symbol("parameter_list", false), parse_tree)
        collapse_node(symbol("typed_parameter_list", false), parse_tree)
        collapse_node(symbol("unorderd_list_part", false), parse_tree)
        collapse_node(symbol("if_comp_pred", false), parse_tree)
        collapse_node(symbol("declaration_block", false), parse_tree)
        collapse_node(symbol("type_list", false), parse_tree)
        collapse_node(symbol("opt_type_list", false), parse_tree)
        collapse_node(symbol("template_param_list", false), parse_tree)
        collapse_node(symbol("trait_list", false), parse_tree)
        collapse_node(symbol("dec_type", false), parse_tree)
    }
    fun remove_node(remove: symbol, parse_tree: *tree<symbol>) {
        var to_process = queue<*tree<symbol>>()
        to_process.push(parse_tree)
        while(!to_process.empty()) {
            var node = to_process.pop()
            for (var i = 0; i < node->children.size; i++;) {
                if (!node->children[i] || node->children[i]->data.equal_wo_data(remove)) {
                    /*
                    if (!node->children[i])
                        println("not because null")
                    else {
                        print("not because "); println(remove.name)
                    }
                    */
                    node->children.remove(i)
                    i--;
                } else {
                    /*println(remove.to_string() + " not equal " + node->children[i]->data.to_string())*/
                    to_process.push(node->children[i])
                }
            }
        }
    }
    fun collapse_node(remove: symbol, parse_tree: *tree<symbol>) {
        var to_process = queue<*tree<symbol>>()
        to_process.push(parse_tree)
        while(!to_process.empty()) {
            var node = to_process.pop()
            for (var i = 0; i < node->children.size; i++;) {
                if (node->children[i]->data.equal_wo_data(remove)) {
                    var add_children = node->children[i]->children;
                    // stick child's children between the current children divided
                    // on i, without including i
                    node->children = node->children.slice(0,i) +
                                        add_children + node->children.slice(i+1,-1)
                    i--;
                } else {
                    to_process.push(node->children[i])
                }
            }
        }
    }
}