#include "commands.h"
#include "cmd_util.h"

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

#include "audit.h"
#include "db.h"
#include "util.h"

/* ------------------------------------------------------------------ */
/* report rules (per-org moms mapping)                                 */
/* ------------------------------------------------------------------ */

struct rule_row {
    int64_t id;
    char report[16];
    char box[8];
    char match_type[16];
    char pattern[64];
    int sign;
    int64_t sort_order;
};

static int rule_digits(const char *s, size_t min, size_t max)
{
    size_t n = s ? strlen(s) : 0;
    if (n < min || n > max)
        return 0;
    for (const char *p = s; *p; p++)
        if (*p < '0' || *p > '9')
            return 0;
    return 1;
}

static int rule_validate(const char *box, const char *match_type,
                         const char *pattern, int64_t sign, char *err,
                         size_t errlen)
{
    if (!rule_digits(box, 1, 3)) {
        snprintf(err, errlen, "box must be 1-3 digits");
        return -1;
    }
    if (strcmp(match_type, "account") == 0) {
        if (!rule_digits(pattern, 1, 10)) {
            snprintf(err, errlen,
                     "pattern must be 1-10 digits when match_type is account");
            return -1;
        }
    } else if (strcmp(match_type, "range") == 0) {
        const char *dash = strchr(pattern, '-');
        if (!dash || dash == pattern || !dash[1] || strchr(dash + 1, '-')) {
            snprintf(err, errlen,
                     "pattern must be LO-HI when match_type is range");
            return -1;
        }
        char lo[16], hi[16];
        size_t lon = (size_t)(dash - pattern);
        size_t hin = strlen(dash + 1);
        if (lon >= sizeof lo || hin >= sizeof hi) {
            snprintf(err, errlen, "pattern must be LO-HI with digits");
            return -1;
        }
        memcpy(lo, pattern, lon);
        lo[lon] = '\0';
        memcpy(hi, dash + 1, hin + 1);
        if (!rule_digits(lo, 1, 10) || !rule_digits(hi, 1, 10)) {
            snprintf(err, errlen,
                     "pattern must be LO-HI with 1-10 digits each");
            return -1;
        }
        size_t llo = strlen(lo), lhi = strlen(hi);
        if (llo > lhi || (llo == lhi && strcmp(lo, hi) > 0)) {
            snprintf(err, errlen, "range start must not exceed range end");
            return -1;
        }
    } else if (strcmp(match_type, "type") == 0) {
        if (strcmp(pattern, "asset") != 0 &&
            strcmp(pattern, "liability") != 0 &&
            strcmp(pattern, "equity") != 0 &&
            strcmp(pattern, "revenue") != 0 &&
            strcmp(pattern, "expense") != 0) {
            snprintf(err, errlen,
                     "pattern must be asset, liability, equity, revenue or"
                     " expense when match_type is type");
            return -1;
        }
    } else {
        snprintf(err, errlen, "match_type must be account, range or type");
        return -1;
    }
    if (sign != 1 && sign != -1) {
        snprintf(err, errlen, "sign must be 1 or -1");
        return -1;
    }
    return 0;
}

static int rule_load(sqlite3 *db, int64_t org_id, int64_t id,
                     struct rule_row *row)
{
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            db,
            "SELECT id,report,box,match_type,pattern,sign,sort_order"
            " FROM report_rules WHERE org_id=?1 AND id=?2",
            -1, &st, NULL) != SQLITE_OK)
        return -1;
    sqlite3_bind_int64(st, 1, org_id);
    sqlite3_bind_int64(st, 2, id);
    int found = 0;
    if (sqlite3_step(st) == SQLITE_ROW) {
        memset(row, 0, sizeof *row);
        row->id = sqlite3_column_int64(st, 0);
        snprintf(row->report, sizeof row->report, "%s",
                 sq(sqlite3_column_text(st, 1)));
        snprintf(row->box, sizeof row->box, "%s",
                 sq(sqlite3_column_text(st, 2)));
        snprintf(row->match_type, sizeof row->match_type, "%s",
                 sq(sqlite3_column_text(st, 3)));
        snprintf(row->pattern, sizeof row->pattern, "%s",
                 sq(sqlite3_column_text(st, 4)));
        row->sign = sqlite3_column_int(st, 5);
        row->sort_order = sqlite3_column_int64(st, 6);
        found = 1;
    }
    sqlite3_finalize(st);
    return found ? 0 : -1;
}

static void rule_to_json(yyjson_mut_doc *doc, yyjson_mut_val *o,
                         const struct rule_row *row)
{
    yyjson_mut_obj_add_int(doc, o, "id", row->id);
    yyjson_mut_obj_add_strcpy(doc, o, "report", row->report);
    yyjson_mut_obj_add_strcpy(doc, o, "box", row->box);
    yyjson_mut_obj_add_strcpy(doc, o, "match_type", row->match_type);
    yyjson_mut_obj_add_strcpy(doc, o, "pattern", row->pattern);
    yyjson_mut_obj_add_int(doc, o, "sign", row->sign);
    yyjson_mut_obj_add_int(doc, o, "sort_order", row->sort_order);
}

static yyjson_mut_val *h_report_rule_list(struct req *r)
{
    const char *report = arg_str(r->args, "report");
    sqlite3_stmt *st = NULL;
    const char *sql =
        report ? "SELECT id,report,box,match_type,pattern,sign,sort_order"
                 " FROM report_rules WHERE org_id=?1 AND report=?2"
                 " ORDER BY report,sort_order,box,id"
               : "SELECT id,report,box,match_type,pattern,sign,sort_order"
                 " FROM report_rules WHERE org_id=?1"
                 " ORDER BY report,sort_order,box,id";
    if (sqlite3_prepare_v2(r->db, sql, -1, &st, NULL) != SQLITE_OK)
        return db_error(r);
    sqlite3_bind_int64(st, 1, r->org_id);
    if (report)
        sqlite3_bind_text(st, 2, report, -1, SQLITE_TRANSIENT);
    yyjson_mut_val *items = yyjson_mut_arr(r->rdoc);
    while (sqlite3_step(st) == SQLITE_ROW) {
        struct rule_row row;
        memset(&row, 0, sizeof row);
        row.id = sqlite3_column_int64(st, 0);
        snprintf(row.report, sizeof row.report, "%s",
                 sq(sqlite3_column_text(st, 1)));
        snprintf(row.box, sizeof row.box, "%s",
                 sq(sqlite3_column_text(st, 2)));
        snprintf(row.match_type, sizeof row.match_type, "%s",
                 sq(sqlite3_column_text(st, 3)));
        snprintf(row.pattern, sizeof row.pattern, "%s",
                 sq(sqlite3_column_text(st, 4)));
        row.sign = sqlite3_column_int(st, 5);
        row.sort_order = sqlite3_column_int64(st, 6);
        yyjson_mut_val *o = yyjson_mut_arr_add_obj(r->rdoc, items);
        rule_to_json(r->rdoc, o, &row);
    }
    sqlite3_finalize(st);
    yyjson_mut_val *res = yyjson_mut_obj(r->rdoc);
    yyjson_mut_obj_add_val(r->rdoc, res, "items", items);
    return res;
}

static yyjson_mut_val *h_report_rule_create(struct req *r)
{
    const char *report = arg_str(r->args, "report");
    const char *box = arg_str(r->args, "box");
    const char *match_type = arg_str(r->args, "match_type");
    const char *pattern = arg_str(r->args, "pattern");
    int64_t sign = 1, sort_order = 0;
    arg_int(r->args, "sign", &sign);
    arg_int(r->args, "sort_order", &sort_order);
    if (!report || !box || !match_type || !pattern)
        return fail(r, "INVALID_ARGS",
                    "report, box, match_type and pattern are required");
    if (strcmp(report, "vat") != 0)
        return fail(r, "INVALID_ARGS", "report must be \"vat\"");
    char verr[256];
    if (rule_validate(box, match_type, pattern, sign, verr, sizeof verr) != 0)
        return fail(r, "INVALID_ARGS", verr);
    if (r->dry_run) {
        struct rule_row row;
        memset(&row, 0, sizeof row);
        snprintf(row.report, sizeof row.report, "%s", report);
        snprintf(row.box, sizeof row.box, "%s", box);
        snprintf(row.match_type, sizeof row.match_type, "%s", match_type);
        snprintf(row.pattern, sizeof row.pattern, "%s", pattern);
        row.sign = (int)sign;
        row.sort_order = sort_order;
        yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
        rule_to_json(r->rdoc, o, &row);
        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
        return o;
    }
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            r->db,
            "INSERT INTO report_rules(org_id,report,box,match_type,pattern,"
            "sign,sort_order) VALUES(?1,?2,?3,?4,?5,?6,?7)",
            -1, &st, NULL) != SQLITE_OK)
        return db_error(r);
    sqlite3_bind_int64(st, 1, r->org_id);
    sqlite3_bind_text(st, 2, report, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 3, box, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 4, match_type, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 5, pattern, -1, SQLITE_TRANSIENT);
    sqlite3_bind_int64(st, 6, sign);
    sqlite3_bind_int64(st, 7, sort_order);
    int rc = sqlite3_step(st);
    sqlite3_finalize(st);
    if (rc != SQLITE_DONE)
        return db_sqlite_error(r);
    int64_t id = db_last_id(r->db);
    char *reqjson = audit_args_json(r->args);
    audit_append(r->db, r->org_id, r->sess->user_id, r->sess->token_id,
                 "report_rule.create", reqjson, "OK", NULL);
    free(reqjson);
    struct rule_row row;
    memset(&row, 0, sizeof row);
    row.id = id;
    snprintf(row.report, sizeof row.report, "%s", report);
    snprintf(row.box, sizeof row.box, "%s", box);
    snprintf(row.match_type, sizeof row.match_type, "%s", match_type);
    snprintf(row.pattern, sizeof row.pattern, "%s", pattern);
    row.sign = (int)sign;
    row.sort_order = sort_order;
    yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
    rule_to_json(r->rdoc, o, &row);
    return o;
}

static yyjson_mut_val *h_report_rule_update(struct req *r)
{
    int64_t id = 0;
    arg_int(r->args, "id", &id);
    if (id <= 0)
        return fail(r, "INVALID_ARGS", "id is required");
    struct rule_row row;
    if (rule_load(r->db, r->org_id, id, &row) != 0)
        return fail(r, "NOT_FOUND", "report rule not found");
    const char *box = arg_str(r->args, "box");
    const char *match_type = arg_str(r->args, "match_type");
    const char *pattern = arg_str(r->args, "pattern");
    int64_t sign = row.sign, sort_order = row.sort_order;
    arg_int(r->args, "sign", &sign);
    arg_int(r->args, "sort_order", &sort_order);
    if (box)
        snprintf(row.box, sizeof row.box, "%s", box);
    if (match_type)
        snprintf(row.match_type, sizeof row.match_type, "%s", match_type);
    if (pattern)
        snprintf(row.pattern, sizeof row.pattern, "%s", pattern);
    row.sign = (int)sign;
    row.sort_order = sort_order;
    char verr[256];
    if (rule_validate(row.box, row.match_type, row.pattern, row.sign, verr,
                      sizeof verr) != 0)
        return fail(r, "INVALID_ARGS", verr);
    if (r->dry_run) {
        yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
        rule_to_json(r->rdoc, o, &row);
        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
        return o;
    }
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            r->db,
            "UPDATE report_rules SET box=?3,match_type=?4,pattern=?5,sign=?6,"
            "sort_order=?7 WHERE org_id=?1 AND id=?2",
            -1, &st, NULL) != SQLITE_OK)
        return db_error(r);
    sqlite3_bind_int64(st, 1, r->org_id);
    sqlite3_bind_int64(st, 2, row.id);
    sqlite3_bind_text(st, 3, row.box, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 4, row.match_type, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 5, row.pattern, -1, SQLITE_TRANSIENT);
    sqlite3_bind_int64(st, 6, row.sign);
    sqlite3_bind_int64(st, 7, row.sort_order);
    int rc = sqlite3_step(st);
    sqlite3_finalize(st);
    if (rc != SQLITE_DONE)
        return db_sqlite_error(r);
    if (sqlite3_changes(r->db) == 0)
        return fail(r, "NOT_FOUND", "report rule not found");
    char *reqjson = audit_args_json(r->args);
    audit_append(r->db, r->org_id, r->sess->user_id, r->sess->token_id,
                 "report_rule.update", reqjson, "OK", NULL);
    free(reqjson);
    yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
    rule_to_json(r->rdoc, o, &row);
    return o;
}

static yyjson_mut_val *h_report_rule_delete(struct req *r)
{
    int64_t id = 0;
    arg_int(r->args, "id", &id);
    if (id <= 0)
        return fail(r, "INVALID_ARGS", "id is required");
    struct rule_row row;
    if (rule_load(r->db, r->org_id, id, &row) != 0)
        return fail(r, "NOT_FOUND", "report rule not found");
    if (r->dry_run) {
        yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
        yyjson_mut_obj_add_int(r->rdoc, o, "id", id);
        yyjson_mut_obj_add_bool(r->rdoc, o, "deleted", true);
        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
        return o;
    }
    if (req_exec(r, "DELETE FROM report_rules WHERE org_id=?1 AND id=?2",
                 "ii", r->org_id, id) != 0)
        return NULL;
    if (sqlite3_changes(r->db) == 0)
        return fail(r, "NOT_FOUND", "report rule not found");
    char *reqjson = audit_args_json(r->args);
    audit_append(r->db, r->org_id, r->sess->user_id, r->sess->token_id,
                 "report_rule.delete", reqjson, "OK", NULL);
    free(reqjson);
    yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
    yyjson_mut_obj_add_int(r->rdoc, o, "id", id);
    yyjson_mut_obj_add_bool(r->rdoc, o, "deleted", true);
    return o;
}


static const struct cmd_arg args_report_rule_list[] = {
    { "report", ARG_ENUM, 0, NULL, "vat",
      "Report filter; omit for all reports" },
};

static const struct cmd_arg args_report_rule_create[] = {
    { "report", ARG_ENUM, 1, NULL, "vat", "Report the rule belongs to" },
    { "box", ARG_STR, 1, NULL, NULL, "Blankett box, 1-3 digits" },
    { "match_type", ARG_ENUM, 1, NULL, "account,range,type",
      "How pattern selects accounts" },
    { "pattern", ARG_STR, 1, NULL, NULL,
      "Account, account range or account type" },
    { "sign", ARG_INT, 0, "1", NULL, "1 or -1" },
    { "sort_order", ARG_INT, 0, "0", NULL, "Evaluation order" },
};

static const struct cmd_arg args_report_rule_update[] = {
    { "id", ARG_INT, 1, NULL, NULL, "Rule id" },
    { "box", ARG_STR, 0, NULL, NULL, "Blankett box, 1-3 digits" },
    { "match_type", ARG_ENUM, 0, NULL, "account,range,type",
      "How pattern selects accounts" },
    { "pattern", ARG_STR, 0, NULL, NULL,
      "Account, account range or account type" },
    { "sign", ARG_INT, 0, NULL, NULL, "1 or -1" },
    { "sort_order", ARG_INT, 0, NULL, NULL, "Evaluation order" },
};

static const struct cmd_arg args_report_rule_delete[] = {
    { "id", ARG_INT, 1, NULL, NULL, "Rule id" },
};

const struct command g_cmd_rules[] = {
    { "report.rule_list", "List per-org reporting rules", PERM_READ, 1, 0, 0,
      h_report_rule_list, CMD_ARGS(args_report_rule_list) },
    { "report.rule_create", "Create a reporting rule (owner)", PERM_OWNER, 1, 1,
      1, h_report_rule_create, CMD_ARGS(args_report_rule_create) },
    { "report.rule_update", "Update a reporting rule (owner)", PERM_OWNER, 1, 1,
      1, h_report_rule_update, CMD_ARGS(args_report_rule_update) },
    { "report.rule_delete", "Delete a reporting rule (owner)", PERM_OWNER, 1, 1,
      1, h_report_rule_delete, CMD_ARGS(args_report_rule_delete) },
};

const struct cmd_table g_cmd_table_rules = {
    g_cmd_rules, sizeof g_cmd_rules / sizeof g_cmd_rules[0]
};