#ifndef LNM_HTTP_LOOP
#define LNM_HTTP_LOOP

#include <stdlib.h>

#include "lnm/common.h"
#include "lnm/http/req.h"
#include "lnm/http/res.h"

typedef enum lnm_http_step_err {
  lnm_http_step_err_done = 0,
  lnm_http_step_err_io_needed,
  lnm_http_step_err_close,
  lnm_http_step_err_res,
} lnm_http_step_err;

typedef lnm_http_step_err (*lnm_http_step_fn)(lnm_http_conn *conn);

typedef lnm_err (*lnm_http_ctx_init_fn)(void **c_ctx, void *gctx);

typedef void (*lnm_http_ctx_reset_fn)(void *c_ctx);

typedef void (*lnm_http_ctx_free_fn)(void *c_ctx);

/**
 * Initialize a new `lnm_http_loop`.
 *
 * @param out where to store pointer to new `lnm_http_loop`
 */
lnm_err lnm_http_loop_init(lnm_http_loop **out, void *c_gctx,
                           lnm_http_ctx_init_fn ctx_init,
                           lnm_http_ctx_reset_fn ctx_reset,
                           lnm_http_ctx_free_fn ctx_free);

/**
 * Initialize a new step.
 *
 * @param out where to store pointer to new `lnm_http_step`
 * @param fn step function
 */
lnm_err lnm_http_step_init(lnm_http_step **out, lnm_http_step_fn fn);

/**
 * Append the given step fn to the step.
 *
 * @param out where to store pointer to new `lnm_http_step`
 * @param step step to append new step to
 * @param fn step function
 */
lnm_err lnm_http_step_append(lnm_http_step **out, lnm_http_step *step,
                             lnm_http_step_fn fn);

/**
 * Initialize a new route of type literal.
 *
 * @param out where to store pointer to new `lnm_http_route`
 * @param path literal path to match
 * @param step step to process request with
 */
lnm_err lnm_http_route_init_literal(lnm_http_route **out,
                                    lnm_http_method method, const char *path,
                                    lnm_http_step *step);

/**
 * Initialize a new route of type regex.
 *
 * @param out where to store pointer to new `lnm_http_route`
 * @param pattern regex pattern
 * @param regex_group_count how many regex groups are contained in the pattern
 * @param step step to process request with
 */
lnm_err lnm_http_route_init_regex(lnm_http_route **out, lnm_http_method method,
                                  const char *pattern, int regex_group_count,
                                  lnm_http_step *step);

/**
 * Add a new route to the HTTP route.
 *
 * @param hl HTTP loop to modify
 * @param route route to add
 */
lnm_err lnm_http_loop_route_add(lnm_http_loop *hl, lnm_http_route *route);

lnm_err lnm_http_loop_run(lnm_http_loop *hl, uint16_t port);

void lnm_http_loop_set_api_key(lnm_http_loop *hl, const char *api_key);

void lnm_http_loop_set_server(lnm_http_loop *hl, const char *value);

/**
 * Represents what state an HTTP loop request is currently in.
 */
typedef enum lnm_http_loop_state {
  // Parse the HTTP request
  lnm_http_loop_state_parse_req = 0,
  // Route the request
  lnm_http_loop_state_route,
  // Parse specific headers (e.g. Content-Length)
  lnm_http_loop_state_parse_headers,
  // Execute the various steps defined for the route
  lnm_http_loop_state_steps,
  // Add certain automatically added headers
  lnm_http_loop_state_add_headers,
  // Write the response status line
  lnm_http_loop_state_write_status_line,
  // Write the various response headers
  lnm_http_loop_state_write_headers,
  // Write the request body
  lnm_http_loop_state_write_body,
  // Clean up the request and reset the state for a next request
  lnm_http_loop_state_finish,
} lnm_http_loop_state;

typedef struct lnm_http_loop_gctx {
  struct {
    lnm_http_route **arr;
    size_t len;
  } routes;
  lnm_http_ctx_init_fn ctx_init;
  lnm_http_ctx_reset_fn ctx_reset;
  lnm_http_ctx_free_fn ctx_free;
  const char *api_key;
  const char *server;
  void *c;
} lnm_http_loop_gctx;

typedef struct lnm_http_loop_ctx {
  lnm_http_loop_state state;
  lnm_http_req req;
  lnm_http_res res;
  lnm_http_route *route;
  lnm_http_step *cur_step;
  lnm_http_loop_gctx *g;
  void *c;
} lnm_http_loop_ctx;

lnm_http_step_err lnm_http_loop_step_body_to_buf(lnm_http_conn *conn);

lnm_http_step_err lnm_http_loop_step_auth(lnm_http_conn *conn);

#endif