#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"

/* ------------------------------------------------------------------ */
/* customer register                                                   */
/* ------------------------------------------------------------------ */

#define CUSTOMER_COLUMNS                                                 \
    "id,name,address,postal_code,city,country,vat_nr,email,your_ref,"    \
    "payment_days,notes,active,created_at,COALESCE(updated_at,'')"

static yyjson_mut_val *customer_json(struct req *r, sqlite3_stmt *st)
{
    yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
    yyjson_mut_obj_add_int(r->rdoc, o, "id", sqlite3_column_int64(st, 0));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "name",
                              sq(sqlite3_column_text(st, 1)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "address",
                              sq(sqlite3_column_text(st, 2)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "postal_code",
                              sq(sqlite3_column_text(st, 3)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "city",
                              sq(sqlite3_column_text(st, 4)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "country",
                              sq(sqlite3_column_text(st, 5)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "vat_nr",
                              sq(sqlite3_column_text(st, 6)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "email",
                              sq(sqlite3_column_text(st, 7)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "your_ref",
                              sq(sqlite3_column_text(st, 8)));
    yyjson_mut_obj_add_int(r->rdoc, o, "payment_days",
                           sqlite3_column_int64(st, 9));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "notes",
                              sq(sqlite3_column_text(st, 10)));
    yyjson_mut_obj_add_bool(r->rdoc, o, "active",
                            sqlite3_column_int(st, 11) != 0);
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "created_at",
                              sq(sqlite3_column_text(st, 12)));
    yyjson_mut_obj_add_strcpy(r->rdoc, o, "updated_at",
                              sq(sqlite3_column_text(st, 13)));
    return o;
}

struct customer_input {
    const char *name;
    const char *address;
    const char *postal_code;
    const char *city;
    const char *country;
    const char *vat_nr;
    const char *email;
    const char *your_ref;
    const char *notes;
    int64_t payment_days;
    int have_payment;
    int active;
    int have_active;
};

static void customer_input_read(struct req *r, struct customer_input *in)
{
    memset(in, 0, sizeof *in);
    in->name = arg_str(r->args, "name");
    in->address = arg_str(r->args, "address");
    in->postal_code = arg_str(r->args, "postal_code");
    in->city = arg_str(r->args, "city");
    in->country = arg_str(r->args, "country");
    in->vat_nr = arg_str(r->args, "vat_nr");
    in->email = arg_str(r->args, "email");
    in->your_ref = arg_str(r->args, "your_ref");
    in->notes = arg_str(r->args, "notes");
    in->have_payment = arg_int(r->args, "payment_days", &in->payment_days);
    in->have_active = arg_bool(r->args, "active", &in->active);
}

static int customer_input_validate(struct req *r,
                                   const struct customer_input *in,
                                   int is_create)
{
    if (is_create && (!in->name || !*in->name)) {
        fail(r, "INVALID_ARGS", "name is required");
        return -1;
    }
    if (in->name && !*in->name) {
        fail(r, "INVALID_ARGS", "name cannot be empty");
        return -1;
    }
    if (in->name && strlen(in->name) > 200) {
        fail(r, "INVALID_ARGS", "name is too long");
        return -1;
    }
    static const char *const names[] = {
        "address", "postal_code", "city", "country", "vat_nr",
        "email", "your_ref", "notes",
    };
    static const size_t maxlen[] = { 500, 32, 120, 64, 64, 254, 120, 2000 };
    const char *values[] = { in->address, in->postal_code, in->city,
                             in->country, in->vat_nr, in->email,
                             in->your_ref, in->notes };
    for (size_t i = 0; i < sizeof maxlen / sizeof maxlen[0]; i++) {
        if (values[i] && strlen(values[i]) > maxlen[i]) {
            failf(r, "INVALID_ARGS", "%s is too long", names[i]);
            return -1;
        }
    }
    if (in->have_payment && in->payment_days < 0) {
        fail(r, "INVALID_ARGS", "payment_days must be >= 0");
        return -1;
    }
    return 0;
}

static yyjson_mut_val *customer_lookup(struct req *r, int64_t id, int *found)
{
    sqlite3_stmt *st = NULL;
    *found = 0;
    if (sqlite3_prepare_v2(
            r->db,
            "SELECT " CUSTOMER_COLUMNS " FROM customers"
            " WHERE org_id=?1 AND id=?2",
            -1, &st, NULL) != SQLITE_OK) {
        *found = -1;
        db_error(r);
        return NULL;
    }
    sqlite3_bind_int64(st, 1, r->org_id);
    sqlite3_bind_int64(st, 2, id);
    if (sqlite3_step(st) != SQLITE_ROW) {
        sqlite3_finalize(st);
        return NULL;
    }
    yyjson_mut_val *o = customer_json(r, st);
    sqlite3_finalize(st);
    *found = 1;
    return o;
}

static int customer_name_taken(struct req *r, const char *name, int64_t except_id)
{
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            r->db,
            "SELECT id FROM customers WHERE org_id=?1 AND name=?2"
            " AND id<>?3",
            -1, &st, NULL) != SQLITE_OK) {
        db_error(r);
        return -1;
    }
    sqlite3_bind_int64(st, 1, r->org_id);
    sqlite3_bind_text(st, 2, name, -1, SQLITE_TRANSIENT);
    sqlite3_bind_int64(st, 3, except_id);
    int taken = sqlite3_step(st) == SQLITE_ROW;
    sqlite3_finalize(st);
    return taken;
}

static yyjson_mut_val *h_customer_list(struct req *r)
{
    int active_only = 0;
    arg_bool(r->args, "active_only", &active_only);
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            r->db,
            "SELECT " CUSTOMER_COLUMNS " FROM customers WHERE org_id=?1"
            " AND (?2=0 OR active=1) ORDER BY name COLLATE NOCASE, id",
            -1, &st, NULL) != SQLITE_OK)
        return db_error(r);
    sqlite3_bind_int64(st, 1, r->org_id);
    sqlite3_bind_int(st, 2, active_only);
    yyjson_mut_val *items = yyjson_mut_arr(r->rdoc);
    while (sqlite3_step(st) == SQLITE_ROW)
        yyjson_mut_arr_add_val(items, customer_json(r, st));
    sqlite3_finalize(st);
    yyjson_mut_val *out = yyjson_mut_obj(r->rdoc);
    yyjson_mut_obj_add_val(r->rdoc, out, "items", items);
    return out;
}

static yyjson_mut_val *h_customer_get(struct req *r)
{
    int64_t id = 0;
    if (!arg_int(r->args, "id", &id) || id <= 0)
        return fail(r, "INVALID_ARGS", "id is required");
    int found = 0;
    yyjson_mut_val *o = customer_lookup(r, id, &found);
    if (found < 0)
        return NULL;
    if (!found)
        return fail(r, "NOT_FOUND", "customer not found");
    return o;
}

static yyjson_mut_val *h_customer_create(struct req *r)
{
    struct customer_input in;
    customer_input_read(r, &in);
    if (customer_input_validate(r, &in, 1) != 0)
        return NULL;
    if (!in.have_payment)
        in.payment_days = 30;
    const char *address = in.address ? in.address : "";
    const char *postal = in.postal_code ? in.postal_code : "";
    const char *city = in.city ? in.city : "";
    const char *country = in.country ? in.country : "SE";
    const char *vat = in.vat_nr ? in.vat_nr : "";
    const char *email = in.email ? in.email : "";
    const char *your_ref = in.your_ref ? in.your_ref : "";
    const char *notes = in.notes ? in.notes : "";
    int taken = customer_name_taken(r, in.name, 0);
    if (taken < 0)
        return NULL;
    if (taken)
        return fail(r, "CONFLICT", "a customer with this name already exists");

    if (r->dry_run) {
        yyjson_mut_val *o = yyjson_mut_obj(r->rdoc);
        yyjson_mut_obj_add_int(r->rdoc, o, "id", 0);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "name", in.name);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "address", address);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "postal_code", postal);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "city", city);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "country", country);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "vat_nr", vat);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "email", email);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "your_ref", your_ref);
        yyjson_mut_obj_add_int(r->rdoc, o, "payment_days", in.payment_days);
        yyjson_mut_obj_add_strcpy(r->rdoc, o, "notes", notes);
        yyjson_mut_obj_add_bool(r->rdoc, o, "active", true);
        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
        return o;
    }

    char ts[32];
    util_iso8601(util_now(), ts, sizeof ts);
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            r->db,
            "INSERT INTO customers(org_id,name,address,postal_code,city,country,"
            "vat_nr,email,your_ref,payment_days,notes,created_at)"
            " VALUES(?1,?2,?3,?4,?5,?6,?7,?8,?9,?10,?11,?12)",
            -1, &st, NULL) != SQLITE_OK)
        return db_error(r);
    sqlite3_bind_int64(st, 1, r->org_id);
    sqlite3_bind_text(st, 2, in.name, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 3, address, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 4, postal, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 5, city, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 6, country, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 7, vat, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 8, email, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 9, your_ref, -1, SQLITE_TRANSIENT);
    sqlite3_bind_int64(st, 10, in.payment_days);
    sqlite3_bind_text(st, 11, notes, -1, SQLITE_TRANSIENT);
    sqlite3_bind_text(st, 12, ts, -1, SQLITE_TRANSIENT);
    int rc = sqlite3_step(st);
    sqlite3_finalize(st);
    if (rc != SQLITE_DONE) {
        if ((rc & 0xff) == SQLITE_CONSTRAINT)
            return fail(r, "CONFLICT", "a customer with this name already exists");
        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,
                 "customer.create", reqjson, "OK", NULL);
    free(reqjson);
    int found = 0;
    yyjson_mut_val *o = customer_lookup(r, id, &found);
    if (found < 0)
        return NULL;
    if (!found)
        return fail(r, "INTERNAL", "could not read the new customer");
    return o;
}

static yyjson_mut_val *h_customer_update(struct req *r)
{
    int64_t id = 0;
    if (!arg_int(r->args, "id", &id) || id <= 0)
        return fail(r, "INVALID_ARGS", "id is required");
    struct customer_input in;
    customer_input_read(r, &in);
    if (customer_input_validate(r, &in, 0) != 0)
        return NULL;
    if (!in.name && !in.address && !in.postal_code && !in.city && !in.country &&
        !in.vat_nr && !in.email && !in.your_ref && !in.notes &&
        !in.have_payment && !in.have_active)
        return fail(r, "INVALID_ARGS", "nothing to update");

    int found = 0;
    yyjson_mut_val *existing = customer_lookup(r, id, &found);
    (void)existing;
    if (found < 0)
        return NULL;
    if (!found)
        return fail(r, "NOT_FOUND", "customer not found");
    if (in.name) {
        int taken = customer_name_taken(r, in.name, id);
        if (taken < 0)
            return NULL;
        if (taken)
            return fail(r, "CONFLICT", "a customer with this name already exists");
    }

    if (r->dry_run) {
        sqlite3_stmt *st = NULL;
        if (sqlite3_prepare_v2(
                r->db,
                "SELECT id,COALESCE(?3,name),COALESCE(?4,address),"
                "COALESCE(?5,postal_code),COALESCE(?6,city),"
                "COALESCE(?7,country),COALESCE(?8,vat_nr),"
                "COALESCE(?9,email),COALESCE(?10,your_ref),"
                "CASE WHEN ?11<0 THEN payment_days ELSE ?11 END,"
                "COALESCE(?12,notes),"
                "CASE WHEN ?13<0 THEN active ELSE ?13 END,"
                "created_at,COALESCE(updated_at,'')"
                " FROM customers 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, id);
        const char *texts[] = { in.name, in.address, in.postal_code, in.city,
                                in.country, in.vat_nr, in.email, in.your_ref,
                                in.notes };
        static const int bind_index[] = { 3, 4, 5, 6, 7, 8, 9, 10, 12 };
        for (size_t i = 0; i < sizeof texts / sizeof texts[0]; i++) {
            bind_text_or_null(st, bind_index[i], texts[i]);
        }
        sqlite3_bind_int64(st, 11, in.have_payment ? in.payment_days : -1);
        sqlite3_bind_int64(st, 13, in.have_active ? in.active : -1);
        yyjson_mut_val *o = NULL;
        if (sqlite3_step(st) == SQLITE_ROW)
            o = customer_json(r, st);
        sqlite3_finalize(st);
        if (!o)
            return fail(r, "NOT_FOUND", "customer not found");
        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
        return o;
    }

    char ts[32];
    util_iso8601(util_now(), ts, sizeof ts);
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            r->db,
            "UPDATE customers SET"
            " name=COALESCE(?3,name), address=COALESCE(?4,address),"
            " postal_code=COALESCE(?5,postal_code), city=COALESCE(?6,city),"
            " country=COALESCE(?7,country), vat_nr=COALESCE(?8,vat_nr),"
            " email=COALESCE(?9,email), your_ref=COALESCE(?10,your_ref),"
            " payment_days=CASE WHEN ?11<0 THEN payment_days ELSE ?11 END,"
            " notes=COALESCE(?12,notes),"
            " active=CASE WHEN ?13<0 THEN active ELSE ?13 END,"
            " updated_at=?14 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, id);
    const char *texts[] = { in.name, in.address, in.postal_code, in.city,
                            in.country, in.vat_nr, in.email, in.your_ref,
                            in.notes };
    static const int text_index[] = { 3, 4, 5, 6, 7, 8, 9, 10, 12 };
    for (size_t i = 0; i < sizeof texts / sizeof texts[0]; i++) {
        bind_text_or_null(st, text_index[i], texts[i]);
    }
    sqlite3_bind_int64(st, 11, in.have_payment ? in.payment_days : -1);
    sqlite3_bind_int64(st, 13, in.have_active ? in.active : -1);
    sqlite3_bind_text(st, 14, ts, -1, SQLITE_TRANSIENT);
    int rc = sqlite3_step(st);
    sqlite3_finalize(st);
    if (rc != SQLITE_DONE) {
        if ((rc & 0xff) == SQLITE_CONSTRAINT)
            return fail(r, "CONFLICT", "a customer with this name already exists");
        return db_sqlite_error(r);
    }
    if (sqlite3_changes(r->db) == 0)
        return fail(r, "NOT_FOUND", "customer not found");
    char *reqjson = audit_args_json(r->args);
    audit_append(r->db, r->org_id, r->sess->user_id, r->sess->token_id,
                 "customer.update", reqjson, "OK", NULL);
    free(reqjson);
    found = 0;
    yyjson_mut_val *o = customer_lookup(r, id, &found);
    if (found < 0)
        return NULL;
    if (!found)
        return fail(r, "INTERNAL", "could not read the customer");
    return o;
}

static yyjson_mut_val *h_customer_archive(struct req *r)
{
    int64_t id = 0;
    int active = 0;
    if (!arg_int(r->args, "id", &id) || id <= 0 ||
        !arg_bool(r->args, "active", &active))
        return fail(r, "INVALID_ARGS", "id and active are required");
    int found = 0;
    yyjson_mut_val *existing = customer_lookup(r, id, &found);
    (void)existing;
    if (found < 0)
        return NULL;
    if (!found)
        return fail(r, "NOT_FOUND", "customer 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, "active", active != 0);
        yyjson_mut_obj_add_bool(r->rdoc, o, "dry_run", true);
        return o;
    }

    char ts[32];
    util_iso8601(util_now(), ts, sizeof ts);
    sqlite3_stmt *st = NULL;
    if (sqlite3_prepare_v2(
            r->db,
            "UPDATE customers SET active=?3, updated_at=?4"
            " 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, id);
    sqlite3_bind_int(st, 3, active);
    sqlite3_bind_text(st, 4, ts, -1, SQLITE_TRANSIENT);
    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", "customer not found");
    char *reqjson = audit_args_json(r->args);
    audit_append(r->db, r->org_id, r->sess->user_id, r->sess->token_id,
                 "customer.archive", 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, "active", active != 0);
    return o;
}


static const struct cmd_arg args_customer_list[] = {
    { "active_only", ARG_BOOL, 0, NULL, NULL, "Only active customers" },
};

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

static const struct cmd_arg args_customer_create[] = {
    { "name", ARG_STR, 1, NULL, NULL, "Customer name, unique per org" },
    { "address", ARG_STR, 0, NULL, NULL, "Street address; may contain newlines" },
    { "postal_code", ARG_STR, 0, NULL, NULL, "Postal code" },
    { "city", ARG_STR, 0, NULL, NULL, "City" },
    { "country", ARG_STR, 0, "SE", NULL, "Country code" },
    { "vat_nr", ARG_STR, 0, NULL, NULL, "VAT number" },
    { "email", ARG_STR, 0, NULL, NULL, "E-mail address" },
    { "your_ref", ARG_STR, 0, NULL, NULL, "Customer reference" },
    { "notes", ARG_STR, 0, NULL, NULL, "Free-text notes" },
    { "payment_days", ARG_INT, 0, "30", NULL, "Payment terms in days" },
};

static const struct cmd_arg args_customer_update[] = {
    { "id", ARG_INT, 1, NULL, NULL, "Customer id" },
    { "name", ARG_STR, 0, NULL, NULL, "Customer name, unique per org" },
    { "address", ARG_STR, 0, NULL, NULL, "Street address" },
    { "postal_code", ARG_STR, 0, NULL, NULL, "Postal code" },
    { "city", ARG_STR, 0, NULL, NULL, "City" },
    { "country", ARG_STR, 0, NULL, NULL, "Country code" },
    { "vat_nr", ARG_STR, 0, NULL, NULL, "VAT number" },
    { "email", ARG_STR, 0, NULL, NULL, "E-mail address" },
    { "your_ref", ARG_STR, 0, NULL, NULL, "Customer reference" },
    { "notes", ARG_STR, 0, NULL, NULL, "Free-text notes" },
    { "payment_days", ARG_INT, 0, NULL, NULL, "Payment terms in days" },
    { "active", ARG_BOOL, 0, NULL, NULL, "Active flag" },
};

static const struct cmd_arg args_customer_archive[] = {
    { "id", ARG_INT, 1, NULL, NULL, "Customer id" },
    { "active", ARG_BOOL, 1, NULL, NULL, "false archives, true reactivates" },
};

const struct command g_cmd_customers[] = {
    { "customer.list", "List customers ordered by name", PERM_READ, 1, 0, 0,
      h_customer_list, CMD_ARGS(args_customer_list) },
    { "customer.get", "Get one customer", PERM_READ, 1, 0, 0, h_customer_get,
      CMD_ARGS(args_customer_get) },
    { "customer.create", "Create a customer", PERM_WRITE, 1, 1, 1,
      h_customer_create, CMD_ARGS(args_customer_create) },
    { "customer.update", "Update a customer (merged)", PERM_WRITE, 1, 1, 1,
      h_customer_update, CMD_ARGS(args_customer_update) },
    { "customer.archive", "Archive or reactivate a customer", PERM_WRITE, 1, 1,
      1, h_customer_archive, CMD_ARGS(args_customer_archive) },
};

const struct cmd_table g_cmd_table_customers = {
    g_cmd_customers, sizeof g_cmd_customers / sizeof g_cmd_customers[0]
};