/*
 * Copyright 1993, 1995 Christopher Seiwald.
 *
 * This file is part of Jam - see jam.c for Copyright information.
 */

/*  This file is ALSO:
 *  Copyright 2022 René Ferdinand Rivera Morell
 *  Copyright 2001-2004 David Abrahams.
 *  Distributed under the Boost Software License, Version 1.0.
 *  (See accompanying file LICENSE.txt or
 * https://www.bfgroup.xyz/b2/LICENSE.txt)
 */

/*
 * rules.h -  targets, rules, and related information
 *
 * This file describes the structures holding the targets, rules, and related
 * information accumulated by interpreting the statements of the jam files.
 *
 * The following are defined:
 *
 *  RULE - a generic jam rule, the product of RULE and ACTIONS.
 *  ACTIONS - a chain of ACTIONs.
 *  ACTION - a RULE instance with targets and sources.
 *  SETTINGS - variables to set when executing a TARGET's ACTIONS.
 *  TARGETS - a chain of TARGETs.
 *  TARGET - an entity (e.g. a file) that can be built.
 */

#ifndef RULES_DWA_20011020_H
#define RULES_DWA_20011020_H

#include "config.h"
#include "function.h"
#include "mem.h"
#include "modules.h"
#include "timestamp.h"
#include <utility>

typedef struct _rule RULE;
typedef struct _target TARGET;
typedef struct _targets TARGETS;
typedef struct _action ACTION;
typedef struct _actions ACTIONS;
typedef struct _settings SETTINGS;

typedef RULE * rule_ptr;
typedef TARGET * target_ptr;
typedef TARGETS * targets_ptr;
typedef ACTION * action_ptr;
typedef ACTIONS * actions_ptr;
typedef SETTINGS * settings_ptr;

typedef RULE & rule_ref;
typedef TARGET & target_ref;
typedef TARGETS & targets_ref;
typedef ACTION & action_ref;
typedef ACTIONS & actions_ref;
typedef SETTINGS & settings_ref;

using rule_uptr = b2::jam::unique_jptr<_rule>;
using target_uptr = b2::jam::unique_jptr<_target>;
using targets_uptr = b2::jam::unique_jptr<_targets>;
using action_uptr = b2::jam::unique_jptr<_action>;
using actions_uptr = b2::jam::unique_jptr<_actions>;
using settings_uptr = b2::jam::unique_jptr<_settings>;

/* RULE - a generic jam rule, the product of RULE and ACTIONS. */

/* Build actions corresponding to a rule. */
struct rule_actions
{
	int reference_count;
	function_ptr command; /* command string from ACTIONS */
	list_ptr bindlist;
	int flags; /* modifiers on ACTIONS */
};

#define RULE_NEWSRCS 0x01 /* $(>) is updated sources only */
#define RULE_TOGETHER 0x02 /* combine actions on single target */
#define RULE_IGNORE 0x04 /* ignore return status of executes */
#define RULE_QUIETLY 0x08 /* do not mention it unless verbose */
#define RULE_PIECEMEAL 0x10 /* split exec so each $(>) is small */
#define RULE_EXISTING 0x20 /* $(>) is pre-existing sources only */

typedef struct rule_actions * rule_actions_ptr;

struct _rule
{
	b2::value_ptr name;
	function_ptr procedure;
	rule_actions_ptr actions; /* build actions, or NULL for no actions */
	module_ptr module; /* module in which this rule is executed */
	int exported; /* nonzero if this rule is supposed to appear in
				   * the global module and be automatically
				   * imported into other modules
				   */
};

/* ACTIONS - a chain of ACTIONs. */
struct _actions
{
	actions_ptr next;
	actions_ptr tail; /* valid only for head */
	action_ptr action;
};

/* ACTION - a RULE instance with targets and sources. */
struct _action
{
	rule_ptr rule;
	targets_uptr targets;
	targets_uptr sources; /* aka $(>) */
	char running; /* has been started */
#define A_INIT 0
#define A_RUNNING_NOEXEC 1
#define A_RUNNING 2
	int refs;

	/* WARNING: These variables are used to pass state required by make1cmds and
	 * are not valid anywhere else.
	 */
	void * first_cmd; /* Pointer to the first CMD created by this action */
	void * last_cmd; /* Pointer to the last CMD created by this action */
};

/* SETTINGS - variables to set when executing a TARGET's ACTIONS. */
struct _settings
{
	settings_ptr next;
	b2::value_ptr symbol; /* symbol name for var_set() */
	list_ptr value; /* symbol value for var_set() */
};

/* TARGETS - a chain of TARGETs. */
struct _targets
{
	targets_uptr next = nullptr;
	targets_ptr tail = nullptr; /* valid only for head */
	target_ptr target = nullptr;

	~_targets()
	{
		targets_uptr sink = std::move(next);
		while (sink) sink = std::move(sink->next);
	}
};

/* TARGET - an entity (e.g. a file) that can be built. */
struct _target
{
	b2::value_ptr name;
	b2::value_ptr boundname; /* if search() relocates target */
	actions_ptr actions; /* rules to execute, if any */
	settings_ptr settings; /* variables to define */

	targets_uptr depends; /* dependencies */
	targets_uptr dependants; /* the inverse of dependencies */
	targets_uptr rebuilds; /* targets that should be force-rebuilt
							* whenever this one is
							*/
	target_ptr includes; /* internal includes node */

	timestamp time; /* update time */
	timestamp leaf; /* update time of leaf sources */

	short flags; /* status info */

#define T_FLAG_TEMP 0x0001 /* TEMPORARY applied */
#define T_FLAG_NOCARE 0x0002 /* NOCARE applied */
#define T_FLAG_NOTFILE 0x0004 /* NOTFILE applied */
#define T_FLAG_TOUCHED 0x0008 /* ALWAYS applied or -t target */
#define T_FLAG_LEAVES 0x0010 /* LEAVES applied */
#define T_FLAG_NOUPDATE 0x0020 /* NOUPDATE applied */
#define T_FLAG_VISITED 0x0040 /* CWM: Used in debugging */

/* This flag has been added to support a new built-in rule named "RMBAD". It is
 * used to force removal of outdated targets whose dependencies fail to build.
 */
#define T_FLAG_RMOLD 0x0080 /* RMBAD applied */

/* This flag was added to support a new built-in rule named "FAIL_EXPECTED" used
 * to indicate that the result of running a given action should be inverted,
 * i.e. ok <=> fail. Useful for launching certain test runs from a Jamfile.
 */
#define T_FLAG_FAIL_EXPECTED 0x0100 /* FAIL_EXPECTED applied */

#define T_FLAG_INTERNAL 0x0200 /* internal INCLUDES node */

/* Indicates that the target must be a file. Prevents matching non-files, like
 * directories, when a target is searched.
 */
#define T_FLAG_ISFILE 0x0400

#define T_FLAG_PRECIOUS 0x0800

	char binding; /* how target relates to a real file or
				   * folder
				   */

#define T_BIND_UNBOUND 0 /* a disembodied name */
#define T_BIND_MISSING 1 /* could not find real file */
#define T_BIND_PARENTS 2 /* using parent's timestamp */
#define T_BIND_EXISTS 3 /* real file, timestamp valid */

	char fate; /* make0()'s diagnosis */

#define T_FATE_INIT 0 /* nothing done to target */
#define T_FATE_MAKING 1 /* make0(target) on stack */

#define T_FATE_STABLE 2 /* target did not need updating */
#define T_FATE_NEWER 3 /* target newer than parent */

#define T_FATE_SPOIL 4 /* >= SPOIL rebuilds parents */
#define T_FATE_ISTMP 4 /* unneeded temp target oddly present */

#define T_FATE_BUILD 5 /* >= BUILD rebuilds target */
#define T_FATE_TOUCHED 5 /* manually touched with -t */
#define T_FATE_REBUILD 6
#define T_FATE_MISSING 7 /* is missing, needs updating */
#define T_FATE_NEEDTMP 8 /* missing temp that must be rebuild */
#define T_FATE_OUTDATED 9 /* is out of date, needs updating */
#define T_FATE_UPDATE 10 /* deps updated, needs updating */

#define T_FATE_BROKEN 11 /* >= BROKEN ruins parents */
#define T_FATE_CANTFIND 11 /* no rules to make missing target */
#define T_FATE_CANTMAKE 12 /* can not find dependencies */

	char progress; /* tracks make1() progress */

#define T_MAKE_INIT 0 /* make1(target) not yet called */
#define T_MAKE_ONSTACK 1 /* make1(target) on stack */
#define T_MAKE_ACTIVE 2 /* make1(target) in make1b() */
#define T_MAKE_RUNNING 3 /* make1(target) running commands */
#define T_MAKE_DONE 4 /* make1(target) done */
#define T_MAKE_NOEXEC_DONE 5 /* make1(target) done with -n in effect */

#ifdef OPT_SEMAPHORE
#define T_MAKE_SEMAPHORE 5 /* Special target type for semaphores */
#endif

	char status; /* exec_cmd() result */

#ifdef OPT_SEMAPHORE
	target_ptr semaphore; /* used in serialization */
#endif

	int asynccnt; /* child deps outstanding */
	targets_uptr parents; /* used by make1() for completion */
	target_ptr scc_root; /* used by make to resolve cyclic includes
						  */
	target_ptr rescanning; /* used by make0 to mark visited targets
							* when rescanning
							*/
	int depth; /* The depth of the target in the make0
				* stack.
				*/
	char * cmds; /* type-punned command list */

	char const * failed;
};

/* Action related functions. */
void action_free(action_ptr);
actions_ptr actionlist(actions_ptr, action_ptr);
void freeactions(actions_ptr);
settings_ptr addsettings(
	settings_ptr, int flag, b2::value_ptr symbol, list_ptr value);
void pushsettings(module_ptr, settings_ptr);
void popsettings(module_ptr, settings_ptr);
settings_ptr copysettings(settings_ptr);
void freesettings(settings_ptr);
void actions_refer(rule_actions_ptr);
void actions_free(rule_actions_ptr);

/* Rule related functions. */
rule_ptr find_rule(b2::value_ptr rulename, module_ptr m);
rule_ptr bindrule(b2::value_ptr rulename, module_ptr);
rule_ptr import_rule(rule_ptr source, module_ptr, b2::value_ptr name);
void rule_localize(rule_ptr rule, module_ptr module);
rule_ptr new_rule_body(
	module_ptr, b2::value_ptr rulename, function_ptr func, int exprt);
rule_ptr new_rule_actions(module_ptr,
	b2::value_ptr rulename,
	function_ptr command,
	list_ptr bindlist,
	int flags);
void rule_free(rule_ptr);

/* Target related functions. */
void bind_explicitly_located_targets();
target_ptr bindtarget(b2::value_ptr const);
targets_uptr targetchain(targets_uptr, targets_uptr);
void targetentry(targets_uptr &, target_ptr);
void target_include(target_ptr const including, target_ptr const included);
void target_include_many(
	target_ptr const including, list_ptr const included_names);
void targetlist(targets_uptr &, list_ptr target_names);
void touch_target(b2::value_ptr const);
void clear_includes(target_ptr);
target_ptr target_scc(target_ptr);
targets_uptr targets_pop(targets_uptr);

/* Final module cleanup. */
void rules_done();

namespace b2 {
struct target_ref
{
	target_ref(value_ref name)
		: target(bindtarget(name))
	{}

	operator TARGET *() const { return target; }

	void on_set(value_ref n, const list_ref & v)
	{
		list_ref val_to_set(v);
		target->settings = addsettings(
			target->settings, 0 /*VAR_SET*/, n, val_to_set.release());
	}
	template <class N, class V>
	void on_set(N n, V v)
	{
		value_ref name_to_set(n);
		list_ref val_to_set(v);
		target->settings = addsettings(
			target->settings, 0 /*VAR_SET*/, name_to_set, val_to_set.release());
	}

	private:
	TARGET * target = nullptr;
};
} // namespace b2

#endif