/*

 * Copyright (c) 2016 DeNA Co., Ltd., Ichito Nagata

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to

 * deal in the Software without restriction, including without limitation the

 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or

 * sell copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS

 * IN THE SOFTWARE.

 */

#include <inttypes.h>

#include "h2o.h"

struct st_h2o_http2_debug_state_handler_t {

    h2o_handler_t super;

    int hpack_enabled;

};

static int on_req(h2o_handler_t *_self, h2o_req_t *req)

{

    struct st_h2o_http2_debug_state_handler_t *self = (void *)_self;

    static h2o_generator_t generator = {NULL, NULL};

    if (req->conn->callbacks->get_debug_state == NULL) {

        return -1;

    }

    h2o_http2_debug_state_t *debug_state = req->conn->callbacks->get_debug_state(req, self->hpack_enabled);

    // stringify these variables to embed in Debug Header

    h2o_iovec_t conn_flow_in, conn_flow_out;

    conn_flow_in.base = h2o_mem_alloc_pool(&req->pool, char, sizeof(H2O_INT64_LONGEST_STR));

    conn_flow_in.len = sprintf(conn_flow_in.base, "%zd", debug_state->conn_flow_in);

    conn_flow_out.base = h2o_mem_alloc_pool(&req->pool, char, sizeof(H2O_INT64_LONGEST_STR));

    conn_flow_out.len = sprintf(conn_flow_out.base, "%zd", debug_state->conn_flow_out);

    req->res.status = 200;

    h2o_add_header(&req->pool, &req->res.headers, H2O_TOKEN_CONTENT_TYPE, NULL, H2O_STRLIT("application/json; charset=utf-8"));

    h2o_add_header(&req->pool, &req->res.headers, H2O_TOKEN_CACHE_CONTROL, NULL, H2O_STRLIT("no-cache, no-store"));

    h2o_add_header_by_str(&req->pool, &req->res.headers, H2O_STRLIT("conn-flow-in"), 0, NULL, conn_flow_in.base, conn_flow_in.len);

    h2o_add_header_by_str(&req->pool, &req->res.headers, H2O_STRLIT("conn-flow-out"), 0, NULL, conn_flow_out.base,

                          conn_flow_out.len);

    h2o_start_response(req, &generator);

    h2o_send(req, debug_state->json.entries,

             h2o_memis(req->input.method.base, req->input.method.len, H2O_STRLIT("HEAD")) ? 0 : debug_state->json.size,

             H2O_SEND_STATE_FINAL);

    return 0;

}

void h2o_http2_debug_state_register(h2o_hostconf_t *conf, int hpack_enabled)

{

    h2o_pathconf_t *pathconf = h2o_config_register_path(conf, "/.well-known/h2/state", 0);

    struct st_h2o_http2_debug_state_handler_t *self = (void *)h2o_create_handler(pathconf, sizeof(*self));

    self->super.on_req = on_req;

    self->hpack_enabled = hpack_enabled;

}