/* SPDX-License-Identifier: LGPL-2.1+ */

#include "dbus-target.h"

#include "dbus-unit.h"

#include "log.h"

#include "serialize.h"

#include "special.h"

#include "string-util.h"

#include "target.h"

#include "unit-name.h"

#include "unit.h"

static const UnitActiveState state_translation_table[_TARGET_STATE_MAX] = {

        [TARGET_DEAD] = UNIT_INACTIVE,

        [TARGET_ACTIVE] = UNIT_ACTIVE

};

static void target_set_state(Target *t, TargetState state) {

        TargetState old_state;

        assert(t);

        if (t->state != state)

                bus_unit_send_pending_change_signal(UNIT(t), false);

        old_state = t->state;

        t->state = state;

        if (state != old_state)

                log_debug("%s changed %s -> %s",

                          UNIT(t)->id,

                          target_state_to_string(old_state),

                          target_state_to_string(state));

        unit_notify(UNIT(t), state_translation_table[old_state], state_translation_table[state], 0);

}

static int target_add_default_dependencies(Target *t) {

        static const UnitDependency deps[] = {

                UNIT_REQUIRES,

                UNIT_REQUISITE,

                UNIT_WANTS,

                UNIT_BINDS_TO,

                UNIT_PART_OF

        };

        int r;

        unsigned k;

        assert(t);

        if (!UNIT(t)->default_dependencies)

                return 0;

        /* Imply ordering for requirement dependencies on target units. Note that when the user created a contradicting

         * ordering manually we won't add anything in here to make sure we don't create a loop. */

        for (k = 0; k < ELEMENTSOF(deps); k++) {

                Unit *other;

                Iterator i;

                void *v;

                HASHMAP_FOREACH_KEY(v, other, UNIT(t)->dependencies[deps[k]], i) {

                        r = unit_add_default_target_dependency(other, UNIT(t));

                        if (r < 0)

                                return r;

                }

        }

        if (unit_has_name(UNIT(t), SPECIAL_SHUTDOWN_TARGET))

                return 0;

        /* Make sure targets are unloaded on shutdown */

        return unit_add_two_dependencies_by_name(UNIT(t), UNIT_BEFORE, UNIT_CONFLICTS, SPECIAL_SHUTDOWN_TARGET, true, UNIT_DEPENDENCY_DEFAULT);

}

static int target_load(Unit *u) {

        Target *t = TARGET(u);

        int r;

        assert(t);

        r = unit_load_fragment_and_dropin(u);

        if (r < 0)

                return r;

        /* This is a new unit? Then let's add in some extras */

        if (u->load_state == UNIT_LOADED) {

                r = target_add_default_dependencies(t);

                if (r < 0)

                        return r;

        }

        return 0;

}

static int target_coldplug(Unit *u) {

        Target *t = TARGET(u);

        assert(t);

        assert(t->state == TARGET_DEAD);

        if (t->deserialized_state != t->state)

                target_set_state(t, t->deserialized_state);

        return 0;

}

static void target_dump(Unit *u, FILE *f, const char *prefix) {

        Target *t = TARGET(u);

        assert(t);

        assert(f);

        fprintf(f,

                "%sTarget State: %s\n",

                prefix, target_state_to_string(t->state));

}

static int target_start(Unit *u) {

        Target *t = TARGET(u);

        int r;

        assert(t);

        assert(t->state == TARGET_DEAD);

        r = unit_acquire_invocation_id(u);

        if (r < 0)

                return r;

        target_set_state(t, TARGET_ACTIVE);

        return 1;

}

static int target_stop(Unit *u) {

        Target *t = TARGET(u);

        assert(t);

        assert(t->state == TARGET_ACTIVE);

        target_set_state(t, TARGET_DEAD);

        return 1;

}

static int target_serialize(Unit *u, FILE *f, FDSet *fds) {

        Target *s = TARGET(u);

        assert(s);

        assert(f);

        assert(fds);

        (void) serialize_item(f, "state", target_state_to_string(s->state));

        return 0;

}

static int target_deserialize_item(Unit *u, const char *key, const char *value, FDSet *fds) {

        Target *s = TARGET(u);

        assert(u);

        assert(key);

        assert(value);

        assert(fds);

        if (streq(key, "state")) {

                TargetState state;

                state = target_state_from_string(value);

                if (state < 0)

                        log_debug("Failed to parse state value %s", value);

                else

                        s->deserialized_state = state;

        } else

                log_debug("Unknown serialization key '%s'", key);

        return 0;

}

_pure_ static UnitActiveState target_active_state(Unit *u) {

        assert(u);

        return state_translation_table[TARGET(u)->state];

}

_pure_ static const char *target_sub_state_to_string(Unit *u) {

        assert(u);

        return target_state_to_string(TARGET(u)->state);

}

const UnitVTable target_vtable = {

        .object_size = sizeof(Target),

        .sections =

                "Unit\0"

                "Target\0"

                "Install\0",

        .load = target_load,

        .coldplug = target_coldplug,

        .dump = target_dump,

        .start = target_start,

        .stop = target_stop,

        .serialize = target_serialize,

        .deserialize_item = target_deserialize_item,

        .active_state = target_active_state,

        .sub_state_to_string = target_sub_state_to_string,

        .bus_vtable = bus_target_vtable,

        .status_message_formats = {

                .finished_start_job = {

                        [JOB_DONE]       = "Reached target %s.",

                },

                .finished_stop_job = {

                        [JOB_DONE]       = "Stopped target %s.",

                },

        },

};