Draft for core:build.

.gitignore

@@ -290,3 +290,5 @@ shared/
 examples/bug/
 build.sh
 !core/debug/
+
+*ols.json*

core/build/cli.odin

@@ -0,0 +1,182 @@
+package build
+
+import "core:strings"
+import "core:os"
+import "core:path/filepath"
+import "core:sync"
+import "core:encoding/json"
+import "core:runtime"
+import "core:fmt"
+import "core:slice"
+import "core:unicode/utf8"
+import "core:unicode"
+import "core:strconv"
+import "core:intrinsics"
+
+
+Flag_Arg :: struct { // -flag:key=val
+	flag: string,
+	key: string,
+	val: string,
+}
+
+Arg :: union {
+	Flag_Arg,
+	string,
+}
+
+Args_Error :: enum {
+	None,
+	Invalid_Format,
+}
+
+// Todo(Dragos): add option to handle ints, floats, bools as strings
+parse_args :: proc(os_args: []string, allocator := context.allocator) -> (args: []Arg, err: Args_Error) {
+	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD(ignore = allocator == context.temp_allocator)
+	context.allocator = allocator
+	args = make([]Arg, len(os_args) - 1)
+	for os_arg, i in os_args[1:] {
+		if os_arg[0] == '-' {
+			flag_arg: Flag_Arg
+			colon_slice := strings.split(os_arg, ":", context.temp_allocator)
+			switch len(colon_slice) {
+			case 1: // only the flag found, no key-val
+				flag_arg.flag = colon_slice[0]
+
+			case 2: // key and/or value found
+				flag_arg.flag = colon_slice[0]
+				equal_slice := strings.split(colon_slice[1], "=", context.temp_allocator)
+				switch len(equal_slice) {
+				case 1: // only key, no value
+					flag_arg.key = equal_slice[0]
+				case 2: /// key and value
+					flag_arg.key = equal_slice[0]
+					flag_arg.val = equal_slice[1]
+				}
+
+			case: // more than 1 colon found. Invalid syntax
+				err = .Invalid_Format
+				return
+			}
+			args[i] = flag_arg
+		} else {
+			args[i] = os_arg
+		}
+	}
+	return
+}
+
+
+Flag_Desc :: struct {
+	mode: Run_Mode,
+	flag: Flag_Arg,
+	help: string,
+}
+
+Cli_Info :: struct {
+	project: ^Project, // this can be projects: []^Project
+	default_target: ^Target,
+}
+
+Cli_Flags_Error :: enum {
+	Incompatible_Flags,
+}
+
+builtin_flags := [?]Flag_Desc {
+	{.Help, {"-help", "", ""}, "Displays information about the build system or the target specified."},
+	{.Dev, {"-ols", "", ""}, "Generates an ols.json for the configuration."},
+	{.Dev, {"-vscode", "", ""}, "Generates .vscode folder for debugging."},
+	{.Dev, {"-build-pre-launch", "", ""}, "Runs the build system before debugging. (WIP)"},
+	{.Dev, {"-include-build-system", "<args>", ""}, "Include the build system as a debugging target. (WIP)"},
+	{.Dev, {"-cwd", "<dir>", ""}, "Sets the CWD to the specified directory."},
+	{.Dev, {"-cwd-workspace", "", ""}, "Sets the CWD to the root of the build system executable."},
+	{.Dev, {"-cwd-out", "", ""}, "Sets the CWD to the output directory specified in the -out odin flag"},
+	{.Dev, {"-launch-args", "<args>", ""}, "The arguments to be sent to the output executable when debugging."},
+	{.Dev, {"-dbg", "<debugger name>", ""}, "Debugger type used. Works with -vscode. Sets the ./vscode/launch.json \"type\" argument"},
+}
+
+print_general_help :: proc(info: Cli_Info) {
+	fmt.printf("Syntax: %s <flags> <target>\n", filepath.base(os.args[0]))
+	fmt.printf("Available Targets:\n")
+	for target in info.project.targets {
+		prefixed_name := strings.concatenate({info.project.target_prefix, target.name}, context.temp_allocator)
+		fmt.printf("\t%s\n", prefixed_name)
+	}
+	fmt.println()
+	fmt.printf("Builtin Flags - Only 1 [Type] group per call. Groups are incompatible\n")
+
+	for flag_desc in builtin_flags {
+		fmt.printf("\t%s", flag_desc.flag.flag)
+		if flag_desc.flag.key != "" {
+			fmt.printf(":\"%s\"", flag_desc.flag.key)
+		}
+		if flag_desc.flag.val != "" {
+			fmt.printf("=\"%s\"", flag_desc.flag.key)
+		}
+		fmt.println()
+		fmt.printf("\t\t%s %s\n", mode_strings[flag_desc.mode], flag_desc.help)
+		fmt.println()
+	}
+}
+
+run_cli :: proc(info: Cli_Info, cli_args: []string) -> bool {
+	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
+	args, err := parse_args(cli_args, context.temp_allocator) // cli_args[0] should be the executable
+	target_names_from_args := make_dynamic_array_len_cap([dynamic]string, 0, len(info.project.targets), context.temp_allocator) // This is not fully correct right now
+	filtered_args_by_mode := make([dynamic]Arg, context.temp_allocator)
+	current_mode: Maybe(Run_Mode)
+	last_flag: Flag_Arg
+	for arg in args {
+		#partial switch v in arg {
+		case string: 
+			append(&target_names_from_args, v)
+		case Flag_Arg:
+			flag_found := false
+			for flag_desc in builtin_flags do if flag_desc.flag == v {
+				flag_found = true
+				if current_mode == nil {
+					current_mode = flag_desc.mode
+				}
+				if current_mode != flag_desc.mode {
+					fmt.eprintf("Mode %s set by %s is incompatible with previous mode %s set by previous flag %s. Run `%s -help`` for more details.\n", mode_strings[flag_desc.mode], flag_desc.flag, current_mode.?, last_flag, cli_args[0])
+					return false
+				}
+				last_flag = v
+				append(&filtered_args_by_mode, v)
+				break
+			}
+			if !flag_found {
+				fmt.eprintf("Flag %s does not exist. Run `%s -help` for a list of available flags.\n", v, cli_args[0])
+				return false
+			}
+		}
+	}
+
+	if current_mode == nil do current_mode = .Build
+
+
+	if len(target_names_from_args) > 0 do for name in target_names_from_args {
+		for target in info.project.targets {
+			prefixed_name := strings.concatenate({info.project.target_prefix, target.name})
+			if _match(name, prefixed_name) {
+				ok := run_target(target, current_mode.?, args)
+				if !ok {
+					fmt.eprintf("Error running %s mode for target %s\n", current_mode.?, target.name)
+					return false
+				}
+			}
+		}
+	} else { // if no target is specified, use the default target
+		if current_mode.? == .Help {
+			print_general_help(info) // No target + -help is a special case. It doesn't print the help of the default target, only the general help.
+		} else {
+			ok := run_target(info.default_target, current_mode.?, args)
+			if !ok {
+				fmt.eprintf("Error running %s mode for target %s\n", current_mode.?, info.default_target.name)
+				return false
+			} 
+		}
+	}
+
+	return true
+}