#include<libwapcaplet/libwapcaplet.h>
#include<stdlib.h>

#include "utils/url.h"
#include "utils/nsurl.h"
#include "utils/utils.h"
#include "utils/corestrings.h"
#include "utils/nsurl.h"
#include "utils/log.h"

#include "content/fetch.h"
#include "content/fetchers.h"
#include "content/fetchers/httplib_kolibri.h"
#include "frontends/kolibrios/kolibri_http.h"

#define STOP __asm__ __volatile__("int3")

extern struct fetch;

struct httpfetcher {
  struct http_msg *handle;
  struct fetch *owner;
  bool headercbdone;
  unsigned int datalen_cb_done;

  struct httpfetcher *next;
};

struct httpfetcher *head = NULL;

void add_to_poll(struct httpfetcher *newfetcher) {

  LOG("-=- add: newfetcher 0x%x, newfetcher->handle 0x%x", newfetcher, newfetcher->handle);
  /* STOP; */

  struct httpfetcher *t = head;
  assert(newfetcher->next == NULL);

  if(head == NULL) {
    head = newfetcher;
    LOG("-=- head was NULL. head is now : 0x%x", head);
    assert(head->next == NULL);
  }
  else {
    while(t->next != NULL) {
      LOG("-=- Passing through httpfetcher : 0x%x", t);
      t = t->next;
    }
    LOG("-=- Adding after httpfetcher : 0x%x", t);
    t->next = newfetcher;
  }
  LOG("-=- done: newfetcher 0x%x, newfetcher->handle 0x%x", newfetcher, newfetcher->handle);
}

void remove_from_poll(struct http_msg *donehttp) {
  struct httpfetcher *t = head, *p = head;
  LOG("-=- remove: (->handle) donehttp 0x%x", donehttp);
  /* STOP; */

  while(t) {
    LOG("------- t = 0x%x, t->handle = 0x%x", t, t->handle);
    /* STOP; */

    if (t->handle == donehttp) {
      LOG(" -- t->handle == donehttp");
      if(t == head) {
        LOG("--- t == head");
        p = t->next;
        head = p;
        LOG("-=- Setting head to 0x%x", p);
        break;
      }
      else {
        LOG("--- t != head");
        LOG("-=- p is 0x%x", p);
        p->next = t->next;
        break;
      }
    }

  p = t;
  t = t->next;
  }  
}

bool init_fetcher(lwc_string *scheme) {
  bool supported_scheme; 
  assert(lwc_string_isequal(scheme, corestring_lwc_http, &supported_scheme) == lwc_error_ok);

  LOG("Initializing http library!");
  debug_board_printf("fetcher_init: Initializing http library!\n");
  if(kolibri_http_init() == 0)
    LOG("[INFO] Loaded http.obj library successfully.\n");
  else {
    LOG("[ERROR] Could not load http.obj library.\n");
    assert(0 && 1);
    return false;
  }

  return supported_scheme;
}

bool supported_url_check(const struct nsurl *url) {
  bool supported;
  lwc_string *url_scheme = nsurl_get_component(url, NSURL_SCHEME);
  assert(lwc_string_isequal(url_scheme, corestring_lwc_http, &supported) == lwc_error_ok);
  lwc_string_unref(url_scheme);
  return supported;
}

void *setup_fetch(struct fetch *parent_fetch, struct nsurl *url,
               bool only_2xx, bool downgrade_tls, const char *post_urlenc,
               const struct fetch_multipart_data *post_multipart,
               const char **headers) {

  struct http_msg* request = NULL;

  LOG("[SETUP] Our target URL: %s", nsurl_access(url));
  LOG("[SETUP] POST urlencoded data: %s", post_urlenc);
  LOG("[SETUP] Headers : %s", *headers);

  struct fetch_multipart_data *printer = post_multipart;

  while(printer != NULL) {
    LOG("Multipart POST : (%s = %s)\n", printer->name, printer->value);
    printer = printer->next;
  }

  if(post_multipart != NULL)
    LOG("[WARNING] We dont support POST multipart yet!\n");

  if(post_urlenc) {
    LOG("http_post: %s", nsurl_access(url));
    request = http_post_asm(nsurl_access(url), NULL, 0, *headers, post_urlenc, strlen(post_urlenc));
  }
  else {
    /* Do a GET */
    LOG("http_get: %s", nsurl_access(url));
    request = http_get_asm(nsurl_access(url), NULL, 0, *headers);
  }

  if(request == NULL) {
    LOG("Failed to allocate http buffer. Could be multiple reasons for failure (like DNS resolution)", request);
    return NULL;
  }

  /* This assert is tricky beacause the http library may fail when it fails to resolve the hostname.
     There is no sane way to understand that the hostname is wrong or needs to be fixed.
     assert leads to a crash for no reason. Disabling it, and the code should handle this from now.
     Returning NuLL from here should just force a BadURL to the user.
  */

  struct httpfetcher *newfetcher = (struct httpfetcher *) malloc(sizeof(struct httpfetcher));
  assert(newfetcher);

  newfetcher->next = NULL;
  newfetcher->handle = request;
  newfetcher->headercbdone = false;
  newfetcher->owner = parent_fetch;
  newfetcher->datalen_cb_done = 0;

  return newfetcher;
}

bool start_fetch(void *httpf) {
  LOG("-=- start_fetch : httpf: 0x%x", httpf);
  add_to_poll((struct httpfetcher *) httpf);
  return true;
}

bool abort_fetch(void *httpf) {
  LOG("aborting fetch 0x%x", ((struct httpfetcher *)httpf)->owner);
  http_disconnect_asm(((struct httpfetcher *)httpf)->handle);
  remove_from_poll(((struct httpfetcher *) httpf)->handle);
  fetch_remove_from_queues(((struct httpfetcher *)httpf)->owner);
  /* fetch_free(((struct httpfetcher *)httpf)->owner); */
  return true;
}

bool free_fetch(void *httpf) {
  LOG("Freeing fetch 0x%x", ((struct httpfetcher *)httpf)->owner);
  http_free_asm((((struct httpfetcher *)httpf)->handle));
  free((struct httpfetcher *)httpf);

  return true;
}

void poll_fetch(lwc_string *scheme) {
  bool supported_scheme;
  assert(lwc_string_isequal(scheme, corestring_lwc_http, &supported_scheme) == lwc_error_ok);
  assert(supported_scheme);

  struct httpfetcher *t = head;

  while(t != NULL) {
    LOG("-- Polling for t 0x%x, http_msg 0x%x, fetch 0x%x [ hcbdone = %s ]", t, t->handle, t->owner, t->headercbdone == true ? "true" : "false");
    LOG("---  http_msg struct at : %x", t->handle);
    LOG("---  Header starts at : %x", &(t->handle->http_header));
    LOG("---  Header Length: %d", t->handle->header_length);
    LOG("---  Content starts at : %x", &(t->handle->content_ptr));
    LOG("---  Content Length (received / total): %d / %d", t->handle->content_received, t->handle->content_length);

    int ret = http_receive_asm(t->handle);

    if(t->handle->flags & HTTP_ERRORS) {
      fetch_msg msg;
      msg.type = FETCH_ERROR;
      LOG("---- [ERROR] http_msg -> flags = 0x%x", t->handle->flags);
      msg.data.header_or_data.buf = (const uint8_t *) "HTTPLIB ERROR";
      msg.data.header_or_data.len = strlen("HTTPLIB ERROR");
      fetch_send_callback(&msg, t->owner);
      t->headercbdone = true;
    }

    if(t->headercbdone == false) {
      if (t->handle->flags & HTTP_GOT_HEADER) {
        LOG("---- Received all HTTP Headers.");
        LOG("---- response status code = %d", t->handle->status);
        fetch_set_http_code(t->owner, t->handle->status);

        if(t->handle->status >= 200 && t->handle->status < 300) {
          fetch_msg msg;
          int plen = 0;
          char *ptr = &(t->handle->http_header);

          while(plen < t->handle->header_length) {
            int j = plen;

            for(;;j++) { 
              if(*(ptr + j) == '\r')
                break;
            }

            msg.type = FETCH_HEADER;
            msg.data.header_or_data.buf = (const uint8_t *)(ptr + plen);
            msg.data.header_or_data.len = j - plen;

            char *xx = (char *) malloc(j - plen + 1);
            strncpy(xx, ptr + plen, j-plen);
            xx[j-plen] = '\0';
            LOG("Headerline: %s", xx);
            fetch_send_callback(&msg, t->owner);
            free(xx);

            plen = j + 2;
          }

          t->headercbdone = true;
        }
        else if(t->handle->status >= 300 && t->handle->status < 400) {
          if(t->handle->status == 304) {
            fetch_msg msg;
            msg.type = FETCH_NOTMODIFIED;
            fetch_send_callback(&msg, t->owner);
            remove_from_poll(t->handle);
            /* t = t->next; */
            t = head;
            continue;
          }
          else {
            LOG("---- finding header 'location' for fetch 0x%x", t->owner);
            fetch_msg msg;
            int lenloc = 0;
            char *tmp = http_find_header_field_asm(t->handle, "location");
            while(!isspace(*(tmp + lenloc))) lenloc++;

            msg.type = FETCH_REDIRECT;
            char *newlocation = malloc(lenloc + 1);
            strncpy(newlocation, tmp, lenloc);
            newlocation[lenloc]='\0';
            msg.data.redirect = newlocation;

            LOG("---- [3xx] : Redirect to %s", msg.data.redirect);
            fetch_send_callback(&msg, t->owner);
            t->headercbdone = true;
            LOG("---- call Remove t->handle = 0x%x", t->handle);
            remove_from_poll(t->handle);
            /* t = t->next; */
            t = head;
            continue;
          }
        }
        else {
          fetch_msg msg;
          msg.type = FETCH_ERROR;
          LOG(" ---- [ERROR] Unhandled HTTP Code : %d", t->handle->status);
          fetch_send_callback(&msg, t->owner);
          t->headercbdone = true;
          remove_from_poll(t->handle);
          fetch_remove_from_queues(t->owner);
          /* fetch_free(t->owner); */
          /* t = t->next; */
          t = head;
          continue;
        }
      }
      else {
        LOG("---- Headers not received yet.");
      }
    }
    else if(ret == -1) {
      /* If data was received send it to netsurf core with FETCH_DATA */
      /* LOG("Doing a data callback; so far : %u vs %u!", t->datalen_cb_done, t->handle->content_received); */

      if(t->handle->content_received > t->datalen_cb_done) {
        fetch_msg msg;
        msg.type = FETCH_DATA;
        msg.data.header_or_data.buf = (const uint8_t *) (t->handle->content_ptr + t->datalen_cb_done);
        msg.data.header_or_data.len = t->handle->content_received - t->datalen_cb_done;
        fetch_send_callback(&msg, t->owner);
        t->datalen_cb_done = t->handle->content_received;
      }
    }
    else if(ret == 0) {
      if(t->handle->content_received > t->datalen_cb_done) {
        /* Callback any remaining data before finishing off */
        fetch_msg msg;
        msg.type = FETCH_DATA;
        msg.data.header_or_data.buf = (const uint8_t *) (t->handle->content_ptr + t->datalen_cb_done);
        msg.data.header_or_data.len = t->handle->content_received - t->datalen_cb_done;
        fetch_send_callback(&msg, t->owner);
        t->datalen_cb_done = t->handle->content_received;
      }

      fetch_msg msg;
      msg.type = FETCH_FINISHED;
      msg.data.header_or_data.buf = NULL;
      msg.data.header_or_data.len = 0;
      fetch_send_callback(&msg, t->owner);
      LOG("---- FETCH_FINISHED for fetch 0x%x", t->owner);

      struct httpfetcher *tnext = t->next;
      remove_from_poll(t->handle);
      fetch_remove_from_queues(t->owner);
      /* fetch_free(t->owner); */
      t = head;
      /* t = tnext; */
      continue;
    }

    LOG("Main loop: t going from 0x%x to 0x%x", t->owner, t->next != NULL ? t->next->owner : "0");
    t = t->next;
  }

  LOG("=Returning from %s", __func__);
}

void finalize_fetcher(lwc_string *scheme) {
  bool supported_scheme;
  assert(lwc_string_isequal(scheme, corestring_lwc_http, &supported_scheme) == lwc_error_ok);
  lwc_string_unref(scheme);
}

static struct fetcher_operation_table fetcher_ops = {
  .initialise = init_fetcher,
  .acceptable = supported_url_check,
  .setup = setup_fetch,
  .start = start_fetch,
  .abort = abort_fetch,
  .free = free_fetch,
  .poll = poll_fetch,
  .finalise = finalize_fetcher
};

nserror fetch_httplib_kolibri_register(void) {
    lwc_string *scheme = lwc_string_ref(corestring_lwc_http);
    return fetcher_add(scheme, &fetcher_ops);
}