#define _XOPEN_SOURCE 700

#include <errno.h>
#include <locale.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "kvmgr.h"
#include "resreq.h"
#include "rusage.h"
#include "section.h"
#include "utils.h"
#include "xce/types.h"
#include "xce_resreq.h"
#include "xce_select_peg.h"
#include "xlist.h"
#include "xvec.h"

/* ── resreq subsystem lifecycle ───────────────────────────────────────────── */

void resreq_init(int optimize_level)
{
    sel_optimize_set(optimize_level);
    sel_node_table_init();
}

void resreq_fini(void)
{
    sel_node_table_fini();
}

/* ── type helpers ─────────────────────────────────────────────────────────── */

res_type_t valtype_to_res_type(int v)
{
    switch (v) {
    case XCE_VAL_NUMERIC: return RES_TYPE_NUMERIC;
    case XCE_VAL_STRING:  return RES_TYPE_STRING;
    case XCE_VAL_BOOLEAN: return RES_TYPE_BOOL;
    default:
        ERROR("valtype_to_res_type: unknown valtype %d", v);
        abort();
    }
}

static int get_parse_errmsg(char** errmsg, const char* data, int pos)
{
    size_t bufsize    = 0;
    FILE*  mem_stream = NULL;
    int    i;

    if ((errmsg == NULL) || (data == NULL) || (pos < 0)) {
        return -EINVAL;
    }

    mem_stream = open_memstream(errmsg, &bufsize);
    if (mem_stream == NULL) {
        return -errno;
    }

    fprintf(mem_stream, "%s\n", data);
    for (i = 0; i < pos - 1; i++) {
        fprintf(mem_stream, " ");
    }

    fprintf(mem_stream, "^Error\n");

    fflush(mem_stream);
    fclose(mem_stream);

    return 1;
}

void kill_resreq_data(xce_resreq_data_t* data)
{
    if (data == NULL) {
        return;
    }

    FREEUP(data->selectString);
    FREEUP(data->rusageString);
    FREEUP(data->spanString);
    FREEUP(data->sameString);
    FREEUP(data->affinityString);
}

void kill_section_ctx(section_context_t* ctx)
{
    if (ctx == NULL) {
        return;
    }

    kill_resreq_data(&(ctx->data));
}

int parse_section(xce_resreq_data_t* resreq, char* data, char** errmsg)
{
    section_context_t      ctx = { 0 };
    xce_section_context_t* p   = NULL;
    int                    rc  = 1;

    if ((resreq == NULL) || (data == NULL) || (errmsg == NULL)) {
        return -EINVAL;
    }

    *errmsg   = NULL;
    ctx.input = data;

    memset(resreq, 0x0, sizeof(*resreq));

    p = xce_section_create(&ctx);
    if (p == NULL) {
        return -errno;
    }

    xce_section_parse(p, NULL);

    if (ctx.has_error) {
        get_parse_errmsg(errmsg, ctx.input, ctx.err_pos);
        rc = -EINVAL;
    } else {
        MOVE_PTR(resreq->selectString, ctx.data.selectString);
        MOVE_PTR(resreq->rusageString, ctx.data.rusageString);
        MOVE_PTR(resreq->spanString, ctx.data.spanString);
        MOVE_PTR(resreq->sameString, ctx.data.sameString);
        MOVE_PTR(resreq->affinityString, ctx.data.affinityString);
    }

    kill_section_ctx(&ctx);

    xce_section_destroy(p);

    return rc;
}

void kill_rusage_value(rusage_value_t* val)
{
    if (val == NULL) {
        return;
    }

    FREEUP(val->res);
}

void kill_rusage_ctx(rusage_context_t* ctx)
{
    if (ctx == NULL) {
        return;
    }
    return;
}

int parse_rusage(xlist_t* rusages, char* data, char** errmsg)
{
    rusage_context_t      ctx = { 0 };
    xce_rusage_context_t* p   = NULL;
    int                   rc  = 1;

    if ((rusages == NULL) || (data == NULL) || (errmsg == NULL)) {
        return -EINVAL;
    }

    *errmsg     = NULL;
    ctx.input   = data;
    ctx.rusages = rusages;

    p = xce_rusage_create(&ctx);
    if (p == NULL) {
        return -errno;
    }

    xce_rusage_parse(p, NULL);

    if (ctx.has_error) {
        get_parse_errmsg(errmsg, ctx.input, ctx.err_pos);
        rc = -EINVAL;
        /* FIXME: need to freeup partial data in rusages */
    }

    kill_rusage_ctx(&ctx);

    xce_rusage_destroy(p);

    return rc;
}

/* Depth pre-scan: count '!' and '(' as depth increments.
 * Returns 0 if depth is within limit, -1 if exceeded. */
static int check_select_depth(const char* input, int max_depth)
{
    int depth = 0;
    const char* p;
    for (p = input; *p; p++) {
        if (*p == '!' || *p == '(') {
            depth++;
            if (depth > max_depth) return -1;
        } else if (*p == ')') {
            if (depth > 0) depth--;
        }
    }
    return 0;
}

static int parse_select(xce_primary_resreq_t* primary, char* selectString,
                        var resmgr, char** errmsg)
{
    select_context_t      ctx;
    xce_select_context_t* p   = NULL;
    int                   rc  = 1;

    /* Without a resource manager, resource names cannot be resolved.
     * Leave primary->select = NULL and succeed — callers that need
     * select evaluation must supply a valid resmgr. */
    if (resmgr == NULL) {
        return 1;
    }

    memset(&ctx, 0, sizeof(ctx));

    /* Length guard */
    if (strlen(selectString) > SELECT_MAX_INPUT_LEN) {
        *errmsg = strdup("select expression exceeds maximum length");
        return -EINVAL;
    }

    /* Depth guard */
    if (check_select_depth(selectString, SELECT_MAX_DEPTH) < 0) {
        *errmsg = strdup("select expression exceeds maximum nesting depth");
        return -EINVAL;
    }

    ctx.resmgr = resmgr;
    ctx.input  = selectString;

    p = xce_select_create(&ctx);
    if (p == NULL) return -errno;

    /* LC_NUMERIC guard: strtod/snprintf in PEG actions must use '.' as the
     * decimal separator regardless of the calling thread's locale setting. */
    locale_t cloc = newlocale(LC_NUMERIC_MASK, "C", (locale_t)0);
    if (cloc == (locale_t)0) {
        xce_select_destroy(p);
        if (sel_get_optimize_level() > 0) {
            ERROR("newlocale(LC_NUMERIC_MASK,C) failed: %s — scheduler cannot "
                  "safely parse numeric resreq values", strerror(errno));
            abort();
        }
        ERROR("newlocale(LC_NUMERIC_MASK,C) failed: %s — rejecting resreq parse",
              strerror(errno));
        *errmsg = strdup("locale initialization failed");
        return -EINVAL;
    }
    locale_t old = uselocale(cloc);

    xce_select_parse(p, NULL);

    uselocale(old);
    freelocale(cloc);

    if (ctx.has_error || ctx.root == NULL) {
        if (ctx.errmsg[0] != '\0')
            *errmsg = strdup(ctx.errmsg);
        else
            get_parse_errmsg(errmsg, selectString, ctx.err_pos);
        rc = -EINVAL;
        goto cleanup_parser;
    }

    /* Phase 4c: flatten AND/OR right-associative chains to left-associative */
    {
        int flat_changed;
        do {
            flat_changed = 0;
            ctx.root = sel_flatten_pass(ctx.root, &flat_changed);
            if (ctx.root == NULL) {
                rc = -ENOMEM;
                goto cleanup_parser;
            }
        } while (flat_changed);
    }

    /* Phase 4d: const-fold (single pass — does not create new flatten opportunities) */
    ctx.root = sel_const_fold_pass(ctx.root);
    if (ctx.root == NULL) {
        rc = -ENOMEM;
        goto cleanup_parser;
    }

    {
        xce_select_t* sel = calloc(1, sizeof(*sel));
        if (sel == NULL) {
            if (sel_get_optimize_level() == 0)
                sel_free_tree(ctx.root);
            rc = -ENOMEM;
        } else {
            sel->root = ctx.root;
            primary->select = sel;
        }
    }

cleanup_parser:
    xce_select_destroy(p);
    return rc;
}

int parse_resreq_primary(xce_primary_resreq_t* primary, char* resreqString,
                         var resmgr, char** errmsg)
{
    int               rc;
    xce_resreq_data_t data;

    if ((primary == NULL) || (resreqString == NULL) || (errmsg == NULL)) {
        return -EINVAL;
    }

    memset(primary, 0x0, sizeof(*primary));

    rc = parse_section(&data, (char*)resreqString, errmsg);
    if (rc < 0) {
        return rc;
    }

    /* Parse select clause BEFORE kill_resreq_data (data.selectString freed there) */
    if (data.selectString != NULL && data.selectString[0] != '\0') {
        rc = parse_select(primary, data.selectString, resmgr, errmsg);
        if (rc < 0) {
            kill_resreq_data(&data);
            return rc;
        }
    }

    xlist_init(&(primary->rusages), 8);

    if ((data.rusageString != NULL) && (strlen(data.rusageString) != 0)) {
        rc = parse_rusage(&(primary->rusages), data.rusageString, errmsg);
        if (rc < 0) {
            kill_resreq_data(&data);

            return rc;
        }
    }

    /* FIXME: add others later */

    kill_resreq_data(&data);
    primary->minTasks = 1;
    primary->maxTasks = 1;

    return rc;
}

void kill_resreq_ctx(resreq_context_t* ctx)
{
    if (ctx == NULL) {
        return;
    }
}

int parse_resreq(xce_resreq_t* resreq, char* data, var resmgr, char** errmsg)
{
    resreq_context_t      ctx = { 0 };
    xce_resreq_context_t* p   = NULL;
    int                   rc  = 1;

    if ((resreq == NULL) || (data == NULL) || (errmsg == NULL)) {
        return -EINVAL;
    }

    *errmsg = NULL;
    memset(resreq, 0x0, sizeof(*resreq));

    ctx.resmgr = resmgr;
    ctx.input  = data;
    ctx.resreq = resreq;

    p = xce_resreq_create(&ctx);
    if (p == NULL) {
        return -errno;
    }

    xce_resreq_parse(p, NULL);

    if (ctx.has_error) {
        get_parse_errmsg(errmsg, ctx.input, ctx.err_pos);
        rc = -EINVAL;
        /* FIXME: need to freeup partial data in resreqs */
    }

    kill_resreq_ctx(&ctx);

    xce_resreq_destroy(p);

    return rc;
}

void kill_primary_resreq(xce_primary_resreq_t* resreq)
{
    int i;

    if (resreq == NULL) {
        return;
    }

    if (resreq->select != NULL) {
        xce_select_node_t* root = resreq->select->root;
        resreq->select->root = NULL;
        if (sel_get_optimize_level() == 0 && root != NULL)
            sel_free_tree(root);
        FREEUP(resreq->select);
    }
    resreq->select = NULL;

    for (i = 0; i < resreq->rusages.count; i++) {
        rusage_value_t* v = (rusage_value_t*)xlist_get(&(resreq->rusages), i);

        if (v == NULL) {
            continue;
        }

        kill_rusage_value(v);

        FREEUP(v);
    }

    xlist_fini(&(resreq->rusages));
}

void kill_compound_resreq(xce_compound_resreq_t* resreq)
{
    int i;

    if (resreq == NULL) {
        return;
    }

    for (i = 0; i < resreq->primaries.count; i++) {
        xce_primary_resreq_t* primary
            = (xce_primary_resreq_t*)xlist_get(&(resreq->primaries), i);

        if (primary == NULL) {
            continue;
        }

        kill_primary_resreq(primary);
        FREEUP(primary);
    }

    xlist_fini(&(resreq->primaries));
}

void kill_alter_resreq(xce_alter_resreq_t* resreq)
{
    int i;

    if (resreq == NULL) {
        return;
    }

    for (i = 0; i < resreq->compounds.count; i++) {
        xce_compound_resreq_t* c
            = (xce_compound_resreq_t*)xlist_get(&(resreq->compounds), i);

        if (c == NULL) {
            continue;
        }

        kill_compound_resreq(c);
        FREEUP(c);
    }

    xlist_fini(&(resreq->compounds));
}

void kill_resreq(xce_resreq_t* resreq)
{
    if (resreq == NULL) {
        return;
    }

    switch (resreq->tag) {
    case XCE_RESREQ_PRIMARY:
        kill_primary_resreq(resreq->u.primary);
        FREEUP(resreq->u.primary);
        break;
    case XCE_RESREQ_COMPOUND:
        kill_compound_resreq(resreq->u.compound);
        FREEUP(resreq->u.compound);
        break;
    case XCE_RESREQ_ALTER:
        kill_alter_resreq(resreq->u.alter);
        FREEUP(resreq->u.alter);
        break;
    default:
        break;
    }
}

static int print_rusages(FILE* fp, xlist_t* rusages, int level)
{
    int i;

    fprintf(fp, "%*sRusages:\n", (int)(2 * level), "");
    for (i = 0; i < rusages->count; i++) {
        rusage_value_t* v = (rusage_value_t*)xlist_get(rusages, i);

        if (v == NULL) {
            continue;
        }

        fprintf(fp, "%*s res %s value %f per %d duration %f decay %d\n",
                (int)(2 * (level + 1)), "", v->res, v->value, v->per_flag,
                v->duration, v->decay_flag);
    }

    return 0;
}
static int print_primary_resreq(FILE* fp, xce_primary_resreq_t* resreq,
                                int level)
{
    fprintf(fp, "%*sPrimary:\n", (int)(2 * level), "");
    fprintf(fp, "%*sTasks: min = %d, max = %d\n", (int)(2 * (level + 1)), "",
            resreq->minTasks, resreq->maxTasks);
#if 0
    fprintf(fp, "%*Select: %s\n", (int)(2*(level +1)),"", "Add later");
#endif
    print_rusages(fp, &(resreq->rusages), level + 1);

    return 0;
}

static int print_compound_resreq(FILE* fp, xce_compound_resreq_t* resreq,
                                 int level)
{
    int i;

    fprintf(fp, "%*sCompound:\n", (int)(2 * level), "");
    for (i = 0; i < resreq->primaries.count; i++) {
        xce_primary_resreq_t* primary
            = (xce_primary_resreq_t*)xlist_get(&(resreq->primaries), i);

        if (primary == NULL) {
            continue;
        }

        print_primary_resreq(fp, primary, level + 1);
    }

    return 0;
}

static int print_alter_resreq(FILE* fp, xce_alter_resreq_t* resreq, int level)
{
    int i;

    fprintf(fp, "%*sAlternative:\n", (int)(2 * level), "");
    for (i = 0; i < resreq->compounds.count; i++) {
        xce_compound_resreq_t* c
            = (xce_compound_resreq_t*)xlist_get(&(resreq->compounds), i);
        if (c == NULL) {
            continue;
        }

        print_compound_resreq(fp, c, level + 1);
    }
    return 0;
}

static int print_resreq(FILE* fp, xce_resreq_t* resreq, int level)
{
    if ((fp == NULL) || (resreq == NULL) || (level < 0)) {
        return -EINVAL;
    }

    switch (resreq->tag) {
    case XCE_RESREQ_PRIMARY:
        return print_primary_resreq(fp, resreq->u.primary, level);
    case XCE_RESREQ_COMPOUND:
        return print_compound_resreq(fp, resreq->u.compound, level);
    case XCE_RESREQ_ALTER:
        return print_alter_resreq(fp, resreq->u.alter, level);
    default:
        break;
    }

    return -EINVAL;
}

int format_resreq(char** buf, xce_resreq_t* resreq)
{
    size_t bufsize = 0;
    FILE*  fp      = NULL;
    int    rc      = 0;

    if ((buf == NULL) || (resreq == NULL)) {
        return -EINVAL;
    }

    fp = open_memstream(buf, &bufsize);
    if (fp == NULL) {
        return -errno;
    }

    rc = print_resreq(fp, resreq, 0);

    fflush(fp);
    fclose(fp);

    return rc;
}

int calc_wanted_global_resvals(xvec_idval_t* resvals, var resmgr,
                               xlist_t* rusages, rusage_per_type_t perflag,
                               int nhosts, int nslots)
{
    int i;

    for (i = 0; i < rusages->count; i++) {
        rusage_value_t*   v = (rusage_value_t*)xlist_get(rusages, i);
        xce_resource_t*   r = NULL;
        float             val;
        rusage_per_type_t perflag1;
        int               rc = 0;

        if (v == NULL) {
            continue;
        }

        lock(resmgr, RTTI_LOCK_READ);
        rc = key_find(resmgr, (void*)v->res, (void**)&r);
        unlock(resmgr);

        if (rc <= 0) {
            continue;
        }

        if (r == NULL) {
            continue;
        }

        if ((r->flags & XCE_RESF_GLOBAL) == 0) {
            continue;
        }

        perflag1 = v->per_flag;
        if (perflag1 == PER_DEFAULT) {
            perflag1 = perflag;
        }

        switch (perflag1) {
        case PER_TASK:
            val = v->value * nslots;
            break;
        case PER_JOB:
            val = v->value;
            break;
        case PER_HOST:
            val = v->value * nhosts;
            break;
        default:
            /* something wrong */
            val = 0.0;
            break;
        }

        xvec_idval_store(resvals, r->idx, val);
    }
    return 0;
}

int calc_wanted_host_resvals(xvec_idval_t* resvals, var resmgr,
                             xlist_t* rusages, rusage_per_type_t perflag,
                             int nhosts, int nslots)
{
    int i;

    for (i = 0; i < rusages->count; i++) {
        rusage_value_t*   v = (rusage_value_t*)xlist_get(rusages, i);
        xce_resource_t*   r = NULL;
        float             val;
        rusage_per_type_t perflag1;
        int               rc = 0;

        if (v == NULL) {
            continue;
        }

        lock(resmgr, RTTI_LOCK_READ);
        rc = key_find(resmgr, (void*)v->res, (void**)&r);
        unlock(resmgr);

        if (rc <= 0) {
            continue;
        }

        if (r == NULL) {
            continue;
        }

        if ((r->flags & XCE_RESF_GLOBAL) != 0) {
            continue;
        }

        perflag1 = v->per_flag;
        if (perflag1 == PER_DEFAULT) {
            perflag1 = perflag;
        }

        if (perflag1 == PER_JOB) {
            /* FIXME: PER_JOB should be global? */
            continue;
        }
        switch (perflag1) {
        case PER_TASK:
            val = v->value * nslots;
            break;
        case PER_HOST:
            val = v->value;
            break;
        default:
            /* something wrong */
            val = 0.0;
            break;
        }

        xvec_idval_store(resvals, r->idx, val);
    }

    return 0;
}