From 8c8a39519325e7b2e967243228dd96a3f544c18f Mon Sep 17 00:00:00 2001
From: Slendi <slendi@socopon.com>
Date: Thu, 8 Feb 2024 18:30:10 +0200
Subject: [PATCH] Add parser for use statment

---
 ast.odin    | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 parser.odin | 26 ++++++++++++++++++++++----
 test.cat    |  8 ++++++--
 3 files changed, 74 insertions(+), 6 deletions(-)

diff --git a/ast.odin b/ast.odin
index 698303f..6c7c70e 100644
--- a/ast.odin
+++ b/ast.odin
@@ -1,6 +1,7 @@
 package main
 
 import "core:fmt"
+import "core:c/libc"
 
 NodeKind :: enum {
 	Integer,
@@ -21,6 +22,8 @@ NodeKind :: enum {
 	Enum,
 	Union,
 
+	Use,
+
 	If,
 }
 
@@ -136,6 +139,49 @@ node_print :: proc(node: ^Node, indent := 0) {
 	}
 }
 
+node_create_use :: proc(range: TextRange, path, alias: [dynamic]u8) -> (ret: ^Node) {
+	path_ := path
+	// Check if the path ends with ".cat", if not, append it.
+	len_path := len(path_)
+	if len(path_) < 4 || path_[len_path - 4] != '.' || path_[len_path - 3] != 'c' || path_[len_path - 2] != 'a' || path_[len_path - 1] != 't' {
+		append(&path_, '.')
+		append(&path_, 'c')
+		append(&path_, 'a')
+		append(&path_, 't')
+	}
+	ret = new(Node)
+	ret^ = {
+		kind = .Use,
+		range = range,
+		value = path_,
+	}
+	if len(alias) != 0 {
+		append(&ret.children, node_create_value(.Identifier, range, alias))
+	} else {
+		// Get the filename, and trucate the extension, then replace any special characters with _
+		new_alias := [dynamic]u8{}
+		for i in 0..<len(path) {
+			if path[i] == '.' {
+				break
+			}
+			if path[i] == '/' {
+				clear(&new_alias)
+				continue
+			}
+			if libc.isalnum(i32(path[i])) == 0 {
+				append(&new_alias, '_')
+			} else {
+				append(&new_alias, path[i])
+			}
+		}
+		if len(new_alias) == 0 {
+			panic("Invalid alias for use statement")
+		}
+		append(&ret.children, node_create_value(.Identifier, range, new_alias))
+	}
+	return
+}
+
 node_create_if :: proc(range: TextRange, condition, then, else_: ^Node) -> (ret: ^Node) {
 	ret = new(Node)
 	ret^ = {
diff --git a/parser.odin b/parser.odin
index 425d366..d6ea77e 100644
--- a/parser.odin
+++ b/parser.odin
@@ -35,10 +35,12 @@ accept :: proc(parser: ^Parser, tok: TokenKind) -> bool {
 }
 
 @(private = "file")
-expect :: proc(parser: ^Parser, tok: TokenKind) {
+expect :: proc(parser: ^Parser, tok: TokenKind) -> bool {
 	if !accept(parser, tok) {
 		append(&g_message_list, message_create(.Error, fmt.aprintf("Expected {}, got {} at {}", tok, parser.tok.kind, "TODO"), parser.tok.range))
+		return false
 	}
+	return true
 }
 
 parser_parse :: proc(parser: ^Parser) -> (ret: ^Node) {
@@ -62,13 +64,15 @@ parser_parse_block :: proc(parser: ^Parser, end: TokenKind) -> (ret: ^Node) {
 
 @(private = "file")
 parser_parse_statement :: proc(parser: ^Parser) -> (ret: ^Node) {
+	range_beg := parser.tok.range
 	if accept(parser, .Semicolon) {
 		ret = nil
 	} else if parser.tok.kind == .If {
-		range_beg := parser.tok.range
 		expect(parser, .If)
 		ret = parser_parse_if_statement(parser)
 		ret.range.start = range_beg.start
+	} else if parser.tok.kind == .Use {
+		ret = parser_parse_use_statement(parser)
 	} else {
 		ret = parser_parse_expression(parser)
 		expect(parser, .Semicolon)
@@ -76,12 +80,26 @@ parser_parse_statement :: proc(parser: ^Parser) -> (ret: ^Node) {
 	return
 }
 
+@(private = "file")
+parser_parse_use_statement :: proc(parser: ^Parser) -> ^Node {
+	range := parser.tok.range
+	expect(parser, .Use)
+	alias : [dynamic]u8
+	if parser.tok.kind == .Identifier {
+		alias = parser.tok.value.([dynamic]u8)
+		parser_next(parser)
+	}
+	tok := parser.tok
+	if !expect(parser, .String) {
+		return nil
+	}
+	return node_create_use(range, tok.value.([dynamic]u8), alias)
+}
+
 @(private = "file")
 parser_parse_if_statement :: proc(parser: ^Parser) -> ^Node {
 	range := parser.tok.range
-	expect(parser, .OpenParen)
 	condition := parser_parse_expression(parser)
-	expect(parser, .CloseParen)
 	expect(parser, .OpenBrace)
 	body := parser_parse_block(parser, .CloseBrace)
 	if accept(parser, .Elif) {
diff --git a/test.cat b/test.cat
index 1980272..437cb14 100644
--- a/test.cat
+++ b/test.cat
@@ -1,8 +1,12 @@
+use "fmt.cat"
+use lib "directory/long_library_name"
+
 fmt.printf "%d + %d = %d File length: %d" a b a + b (io.file_size "file.txt")
 fmt.println "Hello world!"
-if (a == 1) {
+
+if a == 1 {
 	lol
-} elif (b == 2) {
+} elif b == 2 {
 	kek
 } else {
 	aaaaaaa