#include "../debug.h"
#include "cmd.h"

#include <blue/cmd.h>
#include <blue/term.h>
#include <errno.h>
#include <ivy/file.h>
#include <ivy/lang/ast.h>
#include <ivy/lang/codegen.h>
#include <ivy/lang/lex.h>
#include <mie/convert.h>
#include <mie/module.h>
#include <stdio.h>

enum {
	ARG_SOURCE_FILE = 200,
	OPT_SHOW_LEX_TOKENS,
	OPT_SHOW_AST_NODES,
	OPT_SHOW_AST_NODES_POST,
	OPT_SHOW_IR,
};

static enum ivy_status node_codegen(
	struct ivy_ast_node *node, enum ivy_ast_iteration_type iteration_type,
	struct ivy_ast_node_iterator *it, void *arg)
{
	if (iteration_type != IVY_AST_ITERATION_PRE) {
		return IVY_OK;
	}

	struct ivy_codegen *gen = arg;
	struct print_ast_node_args print_args = {.postorder = true};
	print_ast_node(node, iteration_type, it, &print_args);
	return ivy_codegen_push_node(gen, node, node->n_it.it_depth);
}

static int compile_file(const char *path, const b_arglist *args)
{
	bool show_lex = b_arglist_get_count(
				args, OPT_SHOW_LEX_TOKENS, B_COMMAND_INVALID_ID)
	              > 0;
	bool show_ast = b_arglist_get_count(
				args, OPT_SHOW_AST_NODES, B_COMMAND_INVALID_ID)
	              > 0;
	bool show_ast_post
		= b_arglist_get_count(
			  args, OPT_SHOW_AST_NODES_POST, B_COMMAND_INVALID_ID)
	        > 0;
	bool show_ir
		= b_arglist_get_count(args, OPT_SHOW_IR, B_COMMAND_INVALID_ID) > 0;

	FILE *fp = fopen(path, "r");
	if (!fp) {
		b_err("cannot open source file '%s'", path);
		b_i("reason: %s", strerror(errno));
		return -1;
	}

	struct ivy_file *src = ivy_file_from_fp(fp);
	struct ivy_lexer *lex = NULL;
	if (ivy_lexer_create(&lex) != IVY_OK) {
		b_err("failed to initialise Ivy lexer");
		ivy_file_close(src);
		return -1;
	}

	ivy_lexer_set_source(lex, &src->f_base);
	enum ivy_status status = IVY_OK;

	struct ivy_parser *parser = NULL;
	status = ivy_parser_create(&parser);

	if (status != IVY_OK) {
		b_err("failed to initialise Ivy parser");
		ivy_lexer_destroy(lex);
		ivy_file_close(src);
		return -1;
	}

	struct ivy_codegen *codegen;
	status = ivy_codegen_create(&codegen);

	if (status != IVY_OK) {
		b_err("failed to initialise Ivy code generator");
		ivy_parser_destroy(parser, NULL);
		ivy_lexer_destroy(lex);
		ivy_file_close(src);
		return -1;
	}

	while (true) {
		struct ivy_token *tok = ivy_lexer_read(lex);
		status = ivy_lexer_get_status(lex);
		if (status == IVY_ERR_EOF) {
			break;
		}

		if (status != IVY_OK) {
			b_err("failed to parse '%s'", path);
			b_i("reason: lex error (%s)",
			    ivy_status_to_string(ivy_lexer_get_status(lex)));
			break;
		}

		if (show_lex) {
			print_lex_token(tok);
		}

		status = ivy_parser_push_token(parser, tok);

		if (status != IVY_OK) {
			b_err("failed to parse '%s'", path);
			b_i("reason: parse error (%s)",
			    ivy_status_to_string(status));
			ivy_token_destroy(tok);
			break;
		}
	}

	int r = (status == IVY_OK || status == IVY_ERR_EOF) ? 0 : -1;
	ivy_file_close(src);
	ivy_lexer_destroy(lex);

	if (r != 0) {
		return r;
	}

	if (show_ast) {
		struct ivy_ast_node *root = ivy_parser_root_node(parser);
		struct ivy_ast_node_iterator it = {0};
		ivy_ast_node_iterate(root, &it, print_ast_node, NULL);
	}

	if (show_ast && show_ast_post) {
		printf("------\n");
	}

	if (show_ast_post) {
		struct ivy_ast_node *root = ivy_parser_root_node(parser);
		struct ivy_ast_node_iterator it = {};
		struct print_ast_node_args args = {
			.indent = true,
			.postorder = true,
		};
		ivy_ast_node_iterate(root, &it, print_ast_node, &args);
	}

	if (r != 0) {
		ivy_parser_destroy(parser, NULL);
		return r;
	}

	if (!show_ir) {
		ivy_parser_destroy(parser, NULL);
		return 0;
	}

	ivy_codegen_start_module(codegen);

	struct ivy_ast_node *node = ivy_parser_root_node(parser);
	struct ivy_ast_node_iterator it = {0};
	status = ivy_ast_node_iterate(node, &it, node_codegen, codegen);
	if (status != IVY_OK) {
		printf("codegen failed: error %s\n", ivy_status_to_string(status));
	}

	ivy_codegen_push_eof(codegen);

	struct mie_module *mod = NULL;
	ivy_codegen_end_module(codegen, &mod);

	struct mie_ir_converter *convert
		= mie_ir_converter_create(MIE_IR_MEM, MIE_IR_TEXT);
	mie_ir_converter_set_src_value(convert, MIE_VALUE(mod));
	mie_ir_converter_set_dest_file(convert, stdout);
	mie_ir_converter_process(convert);

	mie_value_destroy(MIE_VALUE(mod));
	mie_ir_converter_destroy(convert);
	ivy_codegen_destroy(codegen);

	ivy_parser_destroy(parser, NULL);

	return r;
}

static int compile(const b_command *cmd, const b_arglist *args, const b_array *_)
{
	b_arglist_iterator it;
	b_arglist_foreach_filtered(&it, args, B_COMMAND_INVALID_ID, ARG_SOURCE_FILE)
	{
		b_arglist_value *path = it.value;
		if (path->val_type != B_COMMAND_ARG_STRING) {
			continue;
		}

		printf("%s\n", path->val_str);
		int r = compile_file(path->val_str, args);
		if (r != 0) {
			return r;
		}
	}

	return 0;
}

B_COMMAND(CMD_COMPILE, CMD_ROOT)
{
	B_COMMAND_NAME("compile");
	B_COMMAND_SHORT_NAME('C');
	B_COMMAND_DESC(
		"compile one or more Ivy source files into Ivy object files.");
	B_COMMAND_FLAGS(B_COMMAND_SHOW_HELP_BY_DEFAULT);
	B_COMMAND_FUNCTION(compile);

	B_COMMAND_OPTION(OPT_SHOW_LEX_TOKENS)
	{
		B_OPTION_LONG_NAME("show-lex");
		B_OPTION_SHORT_NAME('l');
		B_OPTION_DESC(
			"print the lexical tokens generated from the input "
			"files.");
	}

	B_COMMAND_OPTION(OPT_SHOW_AST_NODES)
	{
		B_OPTION_LONG_NAME("show-ast");
		B_OPTION_SHORT_NAME('a');
		B_OPTION_DESC(
			"print the abstract syntax tree generated from the "
			"input files.");
	}

	B_COMMAND_OPTION(OPT_SHOW_AST_NODES_POST)
	{
		B_OPTION_LONG_NAME("show-ast-post");
		B_OPTION_SHORT_NAME('A');
		B_OPTION_DESC(
			"print the abstract syntax tree generated from the "
			"input files in post-order.");
	}

	B_COMMAND_OPTION(OPT_SHOW_IR)
	{
		B_OPTION_LONG_NAME("show-ir");
		B_OPTION_SHORT_NAME('i');
		B_OPTION_DESC(
			"print the Mie IR generated from the "
			"input files.");
	}

	B_COMMAND_ARG(ARG_SOURCE_FILE)
	{
		B_ARG_NAME("source file");
		B_ARG_DESC("the .im source files to compile.");
		B_ARG_NR_VALUES(B_ARG_1_OR_MORE_VALUES);
	}

	B_COMMAND_HELP_OPTION();
}