/*

 * Copyright (c) 2015 DeNA Co., Ltd., Kazuho Oku

 *

 * 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 "h2o.h"

#include "h2o/configurator.h"

#define DEFAULT_GZIP_QUALITY 1

#define DEFAULT_BROTLI_QUALITY 1

#define DEFAULT_ZSTD_QUALITY 3

struct compress_configurator_t {

    h2o_configurator_t super;

    h2o_compress_args_t *vars, _vars_stack[H2O_CONFIGURATOR_NUM_LEVELS + 1];

};

static const h2o_compress_args_t all_off = {0, {-1}, {-1}, {-1}},

                                 all_on = {100, {DEFAULT_GZIP_QUALITY}, {DEFAULT_BROTLI_QUALITY}, {DEFAULT_ZSTD_QUALITY}};

static int on_config_gzip(h2o_configurator_command_t *cmd, h2o_configurator_context_t *ctx, yoml_t *node)

{

    struct compress_configurator_t *self = (void *)cmd->configurator;

    int mode;

    if ((mode = (int)h2o_configurator_get_one_of(cmd, node, "OFF,ON")) == -1)

        return -1;

    *self->vars = all_off;

    if (mode != 0)

        self->vars->gzip.quality = DEFAULT_GZIP_QUALITY;

    return 0;

}

static int obtain_quality(yoml_t *node, int min_quality, int max_quality, int default_quality, int *slot)

{

    int tmp;

    if (node->type != YOML_TYPE_SCALAR)

        return -1;

    if (strcasecmp(node->data.scalar, "OFF") == 0) {

        *slot = -1;

        return 0;

    }

    if (strcasecmp(node->data.scalar, "ON") == 0) {

        *slot = default_quality;

        return 0;

    }

    if (sscanf(node->data.scalar, "%d", &tmp) == 1 && (min_quality <= tmp && tmp <= max_quality)) {

        *slot = tmp;

        return 0;

    }

    return -1;

}

static int on_config_compress_min_size(h2o_configurator_command_t *cmd, h2o_configurator_context_t *ctx, yoml_t *node)

{

    struct compress_configurator_t *self = (void *)cmd->configurator;

    return h2o_configurator_scanf(cmd, node, "%zu", &self->vars->min_size);

}

static int on_config_compress(h2o_configurator_command_t *cmd, h2o_configurator_context_t *ctx, yoml_t *node)

{

    struct compress_configurator_t *self = (void *)cmd->configurator;

    size_t i;

    switch (node->type) {

    case YOML_TYPE_SCALAR:

        if (strcasecmp(node->data.scalar, "OFF") == 0) {

            *self->vars = all_off;

        } else if (strcasecmp(node->data.scalar, "ON") == 0) {

            *self->vars = all_on;

        } else {

            h2o_configurator_errprintf(cmd, node, "scalar argument must be either of: `OFF`, `ON`");

            return -1;

        }

        break;

    case YOML_TYPE_SEQUENCE:

        *self->vars = all_off;

        for (i = 0; i != node->data.sequence.size; ++i) {

            yoml_t *element = node->data.sequence.elements[i];

            if (element->type == YOML_TYPE_SCALAR && strcasecmp(element->data.scalar, "gzip") == 0) {

                self->vars->gzip.quality = DEFAULT_GZIP_QUALITY;

            } else if (element->type == YOML_TYPE_SCALAR && strcasecmp(element->data.scalar, "br") == 0) {

                self->vars->brotli.quality = DEFAULT_BROTLI_QUALITY;

            } else if (element->type == YOML_TYPE_SCALAR && strcasecmp(element->data.scalar, "zstd") == 0) {

                self->vars->zstd.quality = DEFAULT_ZSTD_QUALITY;

            } else {

                h2o_configurator_errprintf(cmd, element, "element of the sequence must be either of: `gzip`, `br`, `zstd`");

                return -1;

            }

        }

        break;

    case YOML_TYPE_MAPPING: {

        yoml_t **gzip_node, **br_node, **zstd_node;

        *self->vars = all_off;

        if (h2o_configurator_parse_mapping(cmd, node, NULL, "gzip:*,br:*,zstd:*", &gzip_node, &br_node, &zstd_node) != 0)

            return -1;

        if (gzip_node != NULL && obtain_quality(*gzip_node, 1, 9, DEFAULT_GZIP_QUALITY, &self->vars->gzip.quality) != 0) {

            h2o_configurator_errprintf(cmd, *gzip_node,

                                       "value of gzip attribute must be either of `OFF`, `ON` or an integer value between 1 and 9");

            return -1;

        }

        if (br_node != NULL && obtain_quality(*br_node, 0, 11, DEFAULT_BROTLI_QUALITY, &self->vars->brotli.quality) != 0) {

            h2o_configurator_errprintf(cmd, *br_node,

                                       "value of br attribute must be either of `OFF`, `ON` or an integer between 0 and 11");

            return -1;

        }

        if (zstd_node != NULL && obtain_quality(*zstd_node, 1, 22, DEFAULT_ZSTD_QUALITY, &self->vars->zstd.quality) != 0) {

            h2o_configurator_errprintf(cmd, *zstd_node,

                                       "value of zstd attribute must be either of `OFF`, `ON` or an integer between 1 and 22");

            return -1;

        }

    } break;

    default:

        h2o_fatal("unexpected node type");

        break;

    }

    return 0;

}

static int on_config_enter(h2o_configurator_t *configurator, h2o_configurator_context_t *ctx, yoml_t *node)

{

    struct compress_configurator_t *self = (void *)configurator;

    ++self->vars;

    self->vars[0] = self->vars[-1];

    return 0;

}

static int on_config_exit(h2o_configurator_t *configurator, h2o_configurator_context_t *ctx, yoml_t *node)

{

    struct compress_configurator_t *self = (void *)configurator;

    if (ctx->pathconf != NULL && !h2o_configurator_at_extension_level(ctx) &&

        (self->vars->gzip.quality != -1 || self->vars->brotli.quality != -1 || self->vars->zstd.quality != -1))

        h2o_compress_register(ctx->pathconf, self->vars);

    --self->vars;

    return 0;

}

void h2o_compress_register_configurator(h2o_globalconf_t *conf)

{

    struct compress_configurator_t *c = (void *)h2o_configurator_create(conf, sizeof(*c));

    c->super.enter = on_config_enter;

    c->super.exit = on_config_exit;

    h2o_configurator_define_command(&c->super, "compress",

                                    H2O_CONFIGURATOR_FLAG_GLOBAL | H2O_CONFIGURATOR_FLAG_HOST | H2O_CONFIGURATOR_FLAG_PATH,

                                    on_config_compress);

    h2o_configurator_define_command(&c->super, "compress-minimum-size",

                                    H2O_CONFIGURATOR_FLAG_GLOBAL | H2O_CONFIGURATOR_FLAG_HOST | H2O_CONFIGURATOR_FLAG_PATH |

                                        H2O_CONFIGURATOR_FLAG_EXPECT_SCALAR,

                                    on_config_compress_min_size);

    h2o_configurator_define_command(&c->super, "gzip",

                                    H2O_CONFIGURATOR_FLAG_GLOBAL | H2O_CONFIGURATOR_FLAG_HOST | H2O_CONFIGURATOR_FLAG_PATH |

                                        H2O_CONFIGURATOR_FLAG_EXPECT_SCALAR,

                                    on_config_gzip);

    c->vars = c->_vars_stack;

    c->vars->gzip.quality = -1;

    c->vars->brotli.quality = -1;

    c->vars->zstd.quality = -1;

}