/* cli.c — vmsig spine demonstrator (no real VM).
 *
 * Brings up the context + epoll core, attaches an in-proc control and a set of stub
 * adapters (input/vmhost/memctx) on a single endpoint (VM 0). Proves the bidirectional seam:
 *   UP:    SEAM_UP, VM_LIFECYCLE (vmhost stub tick), MEMCTX (kcr3+locator + RO-fd);
 *   DOWN:  CMD_ACQUIRE+CMD_INPUT -> input adapter -> ACT_ACK (correlation);
 *           CMD_VM QUERY -> vmhost -> VM_LIFECYCLE (addressed reply).
 * The address-space context arrives via MULTICAST: control receives kcr3 and a
 * pre-opened O_RDONLY fd of the RAM region (control does NOT see ram_path; it mmaps
 * the fd itself, write -> EACCES). (vgpu frame perception now lives in an out-of-repo
 * S-lib that consumes this MEMCTX seam — not in signaling.)
 * Shutdown: on SIGINT or automatically, once all paths are proven. */
#include "vmsig.h"
#include <stdio.h>
#include <string.h>
#include <signal.h>
#include <unistd.h>
#include <sys/mman.h>

static vmsig_core* g_core;
static void on_sigint(int s) { (void)s; if (g_core) vmsig_core_stop(g_core); }

typedef struct {
    vmsig_core* core;
    void*       ctl;
    int         total, lifecycles, acks, seams, memctx;
    uint64_t    last_kcr3;
    uint32_t    last_epoch;
    int         sent_first;   /* sent acquire+input+vm on the first lifecycle tick */
} demo;

static const char* kind_name(vmsig_kind k) {
    switch (k) {
    case VMSIG_EV_SEAM_UP:      return "SEAM_UP";
    case VMSIG_EV_SEAM_DOWN:    return "SEAM_DOWN";
    case VMSIG_EV_VM_LIFECYCLE: return "VM_LIFECYCLE";
    case VMSIG_EV_ACT_ACK:      return "ACT_ACK";
    case VMSIG_EV_MEMCTX:       return "MEMCTX";
    default:                    return "?";
    }
}

/* Core -> control: address-space context + pre-opened O_RDONLY fd of the RAM region.
 * Demonstrate RO: mmap(PROT_READ) ok, mmap(PROT_WRITE) -> EACCES. The fd is borrowed
 * (closed by the core after the call) — here we mmap and immediately unmap. */
static int on_memctx(void* user, const vmsig_event* ev, int fd) {
    demo* d = user;
    const vmsig_memctx* m = (const vmsig_memctx*)ev->inln;
    d->memctx++;
    d->last_kcr3 = m->kcr3; d->last_epoch = m->epoch;
    uint32_t nseg = 0;
    const vmsig_memseg* segs = vmsig_memctx_segs(ev, &nseg);
    printf("  UP  MEMCTX       ep=%u kcr3=%#llx low=%#llx epoch=%u nseg=%u rdonly=%d\n",
           (unsigned)ev->endpoint, (unsigned long long)m->kcr3,
           (unsigned long long)m->low, (unsigned)m->epoch, (unsigned)nseg,
           (m->flags & VMSIG_MEMCTX_RDONLY) ? 1 : 0);
    if (fd >= 0 && m->low) {
        void* ro = mmap(NULL, (size_t)m->low, PROT_READ, MAP_SHARED, fd, 0);
        if (ro != MAP_FAILED) {
            void* rw = mmap(NULL, (size_t)m->low, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
            printf("       RO-fd: mmap(PROT_READ) ok, mmap(PROT_WRITE) %s\n",
                   rw == MAP_FAILED ? "EACCES (RO enforced)" : "UNEXPECTEDLY succeeded!");
            if (rw != MAP_FAILED) munmap(rw, (size_t)m->low);
            munmap(ro, (size_t)m->low);
        }
    }
    (void)segs;
    return 0;
}

static int on_event(void* user, const vmsig_event* ev) {
    demo* d = user;
    d->total++;
    switch (ev->kind) {
    case VMSIG_EV_SEAM_UP:      d->seams++;  break;
    case VMSIG_EV_ACT_ACK:      d->acks++;   break;
    default: break;
    }

    if (ev->kind == VMSIG_EV_VM_LIFECYCLE) {
        d->lifecycles++;
        vmsig_vm_state vs; memcpy(&vs, ev->inln, sizeof vs);
        printf("  UP  VM_LIFECYCLE ep=%u state=%u%s\n",
               (unsigned)ev->endpoint, (unsigned)vs.state, ev->origin ? " (reply)" : "");
    } else if (ev->kind != VMSIG_EV_MEMCTX) {   /* MEMCTX is printed in on_memctx */
        printf("  UP  %-12s src=%u ep=%u seq=%u prio=%u\n",
               kind_name(ev->kind), (unsigned)ev->source, (unsigned)ev->endpoint,
               (unsigned)ev->seq, (unsigned)ev->prio);
    }

    /* On the first lifecycle tick: acquire the INPUT lease, send input, and query VM status. */
    if (ev->kind == VMSIG_EV_VM_LIFECYCLE && !ev->origin && !d->sent_first) {
        d->sent_first = 1;
        /* Input is a destructive class: first acquire the exclusive INPUT lease. */
        vmsig_event acq;
        memset(&acq, 0, sizeof acq);
        acq.kind = VMSIG_EV_CMD_ACQUIRE; acq.source = VMSIG_SRC_INPUT; acq.dir = VMSIG_DIR_DOWN;
        acq.prio = VMSIG_PRIO_HIGH; acq.endpoint = 0;
        ((vmsig_lease_req*)acq.inln)->cls = VMSIG_LEASE_INPUT;
        printf("  DOWN CMD_ACQUIRE   INPUT@ep0\n");
        vmsig_inproc_send(d->ctl, &acq);

        vmsig_event in;
        memset(&in, 0, sizeof in);
        in.kind = VMSIG_EV_CMD_INPUT; in.source = VMSIG_SRC_INPUT; in.dir = VMSIG_DIR_DOWN;
        in.prio = VMSIG_PRIO_HIGH; in.endpoint = 0; in.corr = 0xC0FFEEu;
        in.payload.flags = VMSIG_PL_INLINE;
        vmsig_input act; memset(&act, 0, sizeof act);   /* neutral public input contract */
        act.kind = VMSIG_INPUT_MOVE_ABS; act.x = 100; act.y = 100;   /* demo: abs pointer (100,100) */
        memcpy(in.inln, &act, sizeof act);
        printf("  DOWN CMD_INPUT     MOVE_ABS x=100 y=100 corr=0x%X\n", (unsigned)in.corr);
        vmsig_inproc_send(d->ctl, &in);

        vmsig_event vm;
        memset(&vm, 0, sizeof vm);
        vm.kind = VMSIG_EV_CMD_VM; vm.source = VMSIG_SRC_VMHOST; vm.dir = VMSIG_DIR_DOWN;
        vm.prio = VMSIG_PRIO_NORMAL; vm.endpoint = 0; vm.corr = 0x5Au;
        vmsig_vm_cmd vc = { VMSIG_VMOP_QUERY };
        memcpy(vm.inln, &vc, sizeof vc);
        printf("  DOWN CMD_VM        QUERY\n");
        vmsig_inproc_send(d->ctl, &vm);
    }

    /* All paths proven — stop (for automated verification). */
    if (d->memctx >= 1 && d->acks >= 1 && d->lifecycles >= 2) vmsig_core_stop(d->core);
    return 0;
}

int main(void) {
    vmsig_ctx* ctx = vmsig_ctx_new();
    if (!ctx) { fprintf(stderr, "ctx_new failed\n"); return 1; }
    vmsig_core* core = vmsig_core_new(ctx);
    if (!core) { fprintf(stderr, "core_new failed\n"); vmsig_ctx_free(ctx); return 1; }
    g_core = core;
    signal(SIGINT, on_sigint);

    demo d;
    memset(&d, 0, sizeof d);
    d.core = core;

    vmsig_inproc_cfg ccfg;
    memset(&ccfg, 0, sizeof ccfg);
    ccfg.on_event  = on_event;
    ccfg.on_memctx = on_memctx;
    ccfg.user      = &d;
    ccfg.sub.source_mask   = 0;                 /* all sources */
    ccfg.sub.prio_min      = VMSIG_PRIO_BULK;
    ccfg.sub.endpoint_mask = 0;                 /* all VMs       */

    void* ctl = vmsig_inproc_control_new(&ccfg);
    if (!ctl) { fprintf(stderr, "control_new failed\n"); vmsig_core_free(core); vmsig_ctx_free(ctx); return 1; }
    d.ctl = ctl;

    /* Trusted in-proc control: full grant on VM 0 (the policy is set by the embedding
     * program; for an out-of-process poller the grant would be issued upon authentication). */
    vmsig_grant grant;
    memset(&grant, 0, sizeof grant);
    grant.principal     = 1;
    grant.endpoint_mask = 1u << 0;
    grant.source_mask   = 0xFFFFFFFFu;
    grant.cap_mask      = VMSIG_CAP_OBSERVE | VMSIG_CAP_INPUT  | VMSIG_CAP_LIFECYCLE |
                          VMSIG_CAP_MEMCTX | VMSIG_CAP_POWER | VMSIG_CAP_VM;
    vmsig_core_add_control(core, vmsig_inproc_control_ops(), ctl, &grant);

    /* Single endpoint (VM 0), stub adapters (cfg = NULL). */
    if (vmsig_core_add_adapter(core, vmsig_input_ops(),  NULL, 0) < 0 ||
        vmsig_core_add_adapter(core, vmsig_vmhost_ops(), NULL, 0) < 0 ||   /* stub QEMU plane */
        vmsig_core_add_adapter(core, vmsig_memctx_ops(), NULL, 0) < 0) {   /* stub AS context */
        fprintf(stderr, "add_adapter failed\n");
        vmsig_core_free(core); vmsig_ctx_free(ctx); return 1;
    }

    printf("vmsig_cli: loop started (Ctrl-C to stop)\n");
    int rc = vmsig_core_run(core);
    printf("vmsig_cli: loop finished rc=%d (events=%d seams=%d lifecycles=%d acks=%d memctx=%d kcr3=%#llx epoch=%u)\n",
           rc, d.total, d.seams, d.lifecycles, d.acks, d.memctx,
           (unsigned long long)d.last_kcr3, (unsigned)d.last_epoch);

    vmsig_core_free(core);
    vmsig_ctx_free(ctx);
    return rc;
}