/*
 * libvo common functions, variables used by many/all drivers.
 *
 * This file is part of MPlayer.
 *
 * MPlayer is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * MPlayer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with MPlayer; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <stdbool.h>

#include <unistd.h>

#include <libavutil/common.h>

#include "talloc.h"

#include "config.h"
#include "osdep/timer.h"
#include "mpvcore/options.h"
#include "mpvcore/bstr.h"
#include "vo.h"
#include "aspect.h"
#include "mpvcore/input/input.h"
#include "mpvcore/m_config.h"
#include "mpvcore/mp_msg.h"
#include "mpvcore/mpv_global.h"
#include "video/mp_image.h"
#include "video/vfcap.h"
#include "sub/sub.h"

//
// Externally visible list of all vo drivers
//
extern struct vo_driver video_out_x11;
extern struct vo_driver video_out_vdpau;
extern struct vo_driver video_out_xv;
extern struct vo_driver video_out_opengl;
extern struct vo_driver video_out_opengl_hq;
extern struct vo_driver video_out_opengl_old;
extern struct vo_driver video_out_null;
extern struct vo_driver video_out_image;
extern struct vo_driver video_out_lavc;
extern struct vo_driver video_out_caca;
extern struct vo_driver video_out_direct3d;
extern struct vo_driver video_out_direct3d_shaders;
extern struct vo_driver video_out_sdl;
extern struct vo_driver video_out_corevideo;
extern struct vo_driver video_out_vaapi;
extern struct vo_driver video_out_wayland;

const struct vo_driver *video_out_drivers[] =
{
#if HAVE_VDPAU
        &video_out_vdpau,
#endif
#if HAVE_GL
        &video_out_opengl,
#endif
#if HAVE_DIRECT3D
        &video_out_direct3d_shaders,
        &video_out_direct3d,
#endif
#if HAVE_COREVIDEO
        &video_out_corevideo,
#endif
#if HAVE_XV
        &video_out_xv,
#endif
#if HAVE_SDL2
        &video_out_sdl,
#endif
#if HAVE_GL
        &video_out_opengl_old,
#endif
#if HAVE_VAAPI
        &video_out_vaapi,
#endif
#if HAVE_X11
        &video_out_x11,
#endif
        &video_out_null,
        // should not be auto-selected
        &video_out_image,
#if HAVE_CACA
        &video_out_caca,
#endif
#if HAVE_ENCODING
        &video_out_lavc,
#endif
#if HAVE_GL
        &video_out_opengl_hq,
#endif
#if HAVE_WAYLAND
        &video_out_wayland,
#endif
        NULL
};

static bool get_desc(struct m_obj_desc *dst, int index)
{
    if (index >= MP_ARRAY_SIZE(video_out_drivers) - 1)
        return false;
    const struct vo_driver *vo = video_out_drivers[index];
    *dst = (struct m_obj_desc) {
        .name = vo->name,
        .description = vo->description,
        .priv_size = vo->priv_size,
        .priv_defaults = vo->priv_defaults,
        .options = vo->options,
        .hidden = vo->encode,
        .p = vo,
    };
    return true;
}

// For the vo option
const struct m_obj_list vo_obj_list = {
    .get_desc = get_desc,
    .description = "video outputs",
    .aliases = {
        {"gl",        "opengl"},
        {"gl3",       "opengl-hq"},
        {0}
    },
    .allow_unknown_entries = true,
    .allow_trailer = true,
};

static struct vo *vo_create(struct mpv_global *global,
                            struct input_ctx *input_ctx,
                            struct encode_lavc_context *encode_lavc_ctx,
                            char *name, char **args)
{
    struct mp_log *log = mp_log_new(NULL, global->log, "vo");
    struct m_obj_desc desc;
    if (!m_obj_list_find(&desc, &vo_obj_list, bstr0(name))) {
        mp_msg_log(log, MSGL_ERR, "Video output %s not found!\n", name);
        talloc_free(log);
        return NULL;
    };
    struct vo *vo = talloc_ptrtype(NULL, vo);
    *vo = (struct vo) {
        .vo_log = { .log = talloc_steal(vo, log) },
        .log = mp_log_new(vo, log, name),
        .driver = desc.p,
        .opts = &global->opts->vo,
        .encode_lavc_ctx = encode_lavc_ctx,
        .input_ctx = input_ctx,
        .event_fd = -1,
        .registered_fd = -1,
        .aspdat = { .monitor_par = 1 },
    };
    if (vo->driver->encode != !!vo->encode_lavc_ctx)
        goto error;
    struct m_config *config = m_config_from_obj_desc(vo, &desc);
    if (m_config_set_obj_params(config, args) < 0)
        goto error;
    vo->priv = config->optstruct;
    if (vo->driver->preinit(vo))
        goto error;
    return vo;
error:
    talloc_free(vo);
    return NULL;
}

int vo_control(struct vo *vo, uint32_t request, void *data)
{
    return vo->driver->control(vo, request, data);
}

void vo_queue_image(struct vo *vo, struct mp_image *mpi)
{
    if (!vo->config_ok)
        return;
    if (vo->driver->buffer_frames) {
        vo->driver->draw_image(vo, mpi);
        return;
    }
    vo->frame_loaded = true;
    vo->next_pts = mpi->pts;
    assert(!vo->waiting_mpi);
    vo->waiting_mpi = mp_image_new_ref(mpi);
}

int vo_redraw_frame(struct vo *vo)
{
    if (!vo->config_ok)
        return -1;
    if (vo_control(vo, VOCTRL_REDRAW_FRAME, NULL) == true) {
        vo->want_redraw = false;
        vo->redrawing = true;
        return 0;
    }
    return -1;
}

bool vo_get_want_redraw(struct vo *vo)
{
    if (!vo->config_ok)
        return false;
    return vo->want_redraw;
}

int vo_get_buffered_frame(struct vo *vo, bool eof)
{
    if (!vo->config_ok)
        return -1;
    if (vo->frame_loaded)
        return 0;
    if (!vo->driver->buffer_frames)
        return -1;
    vo->driver->get_buffered_frame(vo, eof);
    return vo->frame_loaded ? 0 : -1;
}

void vo_skip_frame(struct vo *vo)
{
    vo_control(vo, VOCTRL_SKIPFRAME, NULL);
    vo->frame_loaded = false;
    mp_image_unrefp(&vo->waiting_mpi);
}

void vo_new_frame_imminent(struct vo *vo)
{
    if (vo->driver->buffer_frames)
        vo_control(vo, VOCTRL_NEWFRAME, NULL);
    else {
        assert(vo->frame_loaded);
        assert(vo->waiting_mpi);
        assert(vo->waiting_mpi->pts == vo->next_pts);
        vo->driver->draw_image(vo, vo->waiting_mpi);
        mp_image_unrefp(&vo->waiting_mpi);
    }
}

void vo_draw_osd(struct vo *vo, struct osd_state *osd)
{
    if (vo->config_ok && vo->driver->draw_osd)
        vo->driver->draw_osd(vo, osd);
}

void vo_flip_page(struct vo *vo, unsigned int pts_us, int duration)
{
    if (!vo->config_ok)
        return;
    if (!vo->redrawing) {
        vo->frame_loaded = false;
        vo->next_pts = MP_NOPTS_VALUE;
    }
    vo->want_redraw = false;
    vo->redrawing = false;
    if (vo->driver->flip_page_timed)
        vo->driver->flip_page_timed(vo, pts_us, duration);
    else
        vo->driver->flip_page(vo);
    vo->hasframe = true;
}

void vo_check_events(struct vo *vo)
{
    if (!vo->config_ok) {
        if (vo->registered_fd != -1)
            mp_input_rm_key_fd(vo->input_ctx, vo->registered_fd);
        vo->registered_fd = -1;
        return;
    }
    vo_control(vo, VOCTRL_CHECK_EVENTS, NULL);
}

void vo_seek_reset(struct vo *vo)
{
    vo_control(vo, VOCTRL_RESET, NULL);
    vo->frame_loaded = false;
    vo->hasframe = false;
    mp_image_unrefp(&vo->waiting_mpi);
}

void vo_destroy(struct vo *vo)
{
    if (vo->registered_fd != -1)
        mp_input_rm_key_fd(vo->input_ctx, vo->registered_fd);
    mp_image_unrefp(&vo->waiting_mpi);
    vo->driver->uninit(vo);
    talloc_free(vo);
}

struct vo *init_best_video_out(struct mpv_global *global,
                               struct input_ctx *input_ctx,
                               struct encode_lavc_context *encode_lavc_ctx)
{
    struct m_obj_settings *vo_list = global->opts->vo.video_driver_list;
    // first try the preferred drivers, with their optional subdevice param:
    if (vo_list && vo_list[0].name) {
        for (int n = 0; vo_list[n].name; n++) {
            // Something like "-vo name," allows fallback to autoprobing.
            if (strlen(vo_list[n].name) == 0)
                goto autoprobe;
            struct vo *vo = vo_create(global, input_ctx, encode_lavc_ctx,
                                      vo_list[n].name, vo_list[n].attribs);
            if (vo)
                return vo;
        }
        return NULL;
    }
autoprobe:
    // now try the rest...
    for (int i = 0; video_out_drivers[i]; i++) {
        struct vo *vo = vo_create(global, input_ctx, encode_lavc_ctx,
                                  (char *)video_out_drivers[i]->name, NULL);
        if (vo)
            return vo;
    }
    return NULL;
}

// Fit *w/*h into the size specified by geo.
static void apply_autofit(int *w, int *h, int scr_w, int scr_h,
                          struct m_geometry *geo, bool allow_upscale)
{
    if (!geo->wh_valid)
        return;

    int dummy;
    int n_w = *w, n_h = *h;
    m_geometry_apply(&dummy, &dummy, &n_w, &n_h, scr_w, scr_h, geo);

    if (!allow_upscale && *w <= n_w && *h <= n_h)
        return;

    // If aspect mismatches, always make the window smaller than the fit box
    double asp = (double)*w / *h;
    double n_asp = (double)n_w / n_h;
    if (n_asp <= asp) {
        *w = n_w;
        *h = n_w / asp;
    } else {
        *w = n_h * asp;
        *h = n_h;
    }
}

// Set window size (vo->dwidth/dheight) and position (vo->dx/dy) according to
// the video display size d_w/d_h.
// NOTE: currently, all GUI backends do their own handling of window geometry
//       additional to this code. This is to deal with initial window placement,
//       fullscreen handling, avoiding resize on config() with no size change,
//       multi-monitor stuff, and possibly more.
static void determine_window_geometry(struct vo *vo, int d_w, int d_h)
{
    struct mp_vo_opts *opts = vo->opts;

    int scr_w = opts->screenwidth;
    int scr_h = opts->screenheight;

    aspect_calc_monitor(vo, &d_w, &d_h);

    apply_autofit(&d_w, &d_h, scr_w, scr_h, &opts->autofit, true);
    apply_autofit(&d_w, &d_h, scr_w, scr_h, &opts->autofit_larger, false);

    vo->dx = (int)(opts->screenwidth - d_w) / 2;
    vo->dy = (int)(opts->screenheight - d_h) / 2;
    m_geometry_apply(&vo->dx, &vo->dy, &d_w, &d_h, scr_w, scr_h,
                     &opts->geometry);

    vo->dx += vo->xinerama_x;
    vo->dy += vo->xinerama_y;
    vo->dwidth = d_w;
    vo->dheight = d_h;
}

static int event_fd_callback(void *ctx, int fd)
{
    struct vo *vo = ctx;
    vo_check_events(vo);
    return MP_INPUT_NOTHING;
}

int vo_reconfig(struct vo *vo, struct mp_image_params *params, int flags)
{
    int d_width = params->d_w;
    int d_height = params->d_h;
    aspect_save_videores(vo, params->w, params->h, d_width, d_height);

    if (vo_control(vo, VOCTRL_UPDATE_SCREENINFO, NULL) == VO_TRUE) {
        determine_window_geometry(vo, params->d_w, params->d_h);
        d_width = vo->dwidth;
        d_height = vo->dheight;
    }
    vo->dwidth = d_width;
    vo->dheight = d_height;

    talloc_free(vo->params);
    vo->params = NULL;

    struct mp_image_params p2 = *params;

    int ret;
    if (vo->driver->reconfig) {
        ret = vo->driver->reconfig(vo, &p2, flags);
    } else {
        // Old config() takes window size, while reconfig() takes aspect (!)
        ret = vo->driver->config(vo, p2.w, p2.h, d_width, d_height, flags,
                                 p2.imgfmt);
        ret = ret ? -1 : 0;
    }
    vo->config_ok = (ret >= 0);
    vo->config_count += vo->config_ok;
    if (vo->config_ok)
        vo->params = talloc_memdup(vo, &p2, sizeof(p2));
    if (vo->registered_fd == -1 && vo->event_fd != -1 && vo->config_ok) {
        mp_input_add_key_fd(vo->input_ctx, vo->event_fd, 1, event_fd_callback,
                            NULL, vo);
        vo->registered_fd = vo->event_fd;
    }
    vo->frame_loaded = false;
    vo->waiting_mpi = NULL;
    vo->redrawing = false;
    vo->hasframe = false;
    if (vo->config_ok) {
        // Legacy
        struct mp_csp_details csp;
        if (vo_control(vo, VOCTRL_GET_YUV_COLORSPACE, &csp) > 0) {
            csp.levels_in = params->colorlevels;
            csp.levels_out = params->outputlevels;
            csp.format = params->colorspace;
            vo_control(vo, VOCTRL_SET_YUV_COLORSPACE, &csp);
        }
    }
    return ret;
}

/**
 * \brief lookup an integer in a table, table must have 0 as the last key
 * \param key key to search for
 * \result translation corresponding to key or "to" value of last mapping
 *         if not found.
 */
int lookup_keymap_table(const struct mp_keymap *map, int key) {
  while (map->from && map->from != key) map++;
  return map->to;
}

static void print_video_rect(struct vo *vo, struct mp_rect src,
                             struct mp_rect dst, struct mp_osd_res osd)
{
    int sw = src.x1 - src.x0, sh = src.y1 - src.y0;
    int dw = dst.x1 - dst.x0, dh = dst.y1 - dst.y0;

    MP_VERBOSE(&vo->vo_log, "Window size: %dx%d\n",
               vo->dwidth, vo->dheight);
    MP_VERBOSE(&vo->vo_log, "Video source: %dx%d (%dx%d)\n",
               vo->aspdat.orgw, vo->aspdat.orgh,
               vo->aspdat.prew, vo->aspdat.preh);
    MP_VERBOSE(&vo->vo_log, "Video display: (%d, %d) %dx%d -> (%d, %d) %dx%d\n",
               src.x0, src.y0, sw, sh, dst.x0, dst.y0, dw, dh);
    MP_VERBOSE(&vo->vo_log, "Video scale: %f/%f\n",
               (double)dw / sw, (double)dh / sh);
    MP_VERBOSE(&vo->vo_log, "OSD borders: l=%d t=%d r=%d b=%d\n",
               osd.ml, osd.mt, osd.mr, osd.mb);
    MP_VERBOSE(&vo->vo_log, "Video borders: l=%d t=%d r=%d b=%d\n",
               dst.x0, dst.y0, vo->dwidth - dst.x1, vo->dheight - dst.y1);
}

// Clamp [start, end) to range [0, size) with various fallbacks.
static void clamp_size(int size, int *start, int *end)
{
    *start = FFMAX(0, *start);
    *end = FFMIN(size, *end);
    if (*start >= *end) {
        *start = 0;
        *end = 1;
    }
}

// Round source to a multiple of 2, this is at least needed for vo_direct3d
// and ATI cards.
#define VID_SRC_ROUND_UP(x) (((x) + 1) & ~1)

static void src_dst_split_scaling(int src_size, int dst_size,
                                  int scaled_src_size, bool unscaled,
                                  float zoom, float align, float pan,
                                  int *src_start, int *src_end,
                                  int *dst_start, int *dst_end,
                                  int *osd_margin_a, int *osd_margin_b)
{
    if (unscaled)
        scaled_src_size = src_size;

    scaled_src_size += zoom * src_size;
    align = (align + 1) / 2;

    *src_start = 0;
    *src_end = src_size;
    *dst_start = (dst_size - scaled_src_size) * align + pan * scaled_src_size;
    *dst_end = *dst_start + scaled_src_size;

    // Distance of screen frame to video
    *osd_margin_a = *dst_start;
    *osd_margin_b = dst_size - *dst_end;

    // Clip to screen
    int s_src = *src_end - *src_start;
    int s_dst = *dst_end - *dst_start;
    if (*dst_start < 0) {
        int border = -(*dst_start) * s_src / s_dst;
        *src_start += VID_SRC_ROUND_UP(border);
        *dst_start = 0;
    }
    if (*dst_end > dst_size) {
        int border = (*dst_end - dst_size) * s_src / s_dst;
        *src_end -= VID_SRC_ROUND_UP(border);
        *dst_end = dst_size;
    }

    if (unscaled && zoom == 1.0) {
        // Force unscaled by reducing the range for src or dst
        int src_s = *src_end - *src_start;
        int dst_s = *dst_end - *dst_start;
        if (src_s > dst_s) {
            *src_end = *src_start + dst_s;
        } else if (src_s < dst_s) {
            *dst_end = *dst_start + src_s;
        }
    }

    // For sanity: avoid bothering VOs with corner cases
    clamp_size(src_size, src_start, src_end);
    clamp_size(dst_size, dst_start, dst_end);
}

// Calculate the appropriate source and destination rectangle to
// get a correctly scaled picture, including pan-scan.
// out_src: visible part of the video
// out_dst: area of screen covered by the video source rectangle
// out_osd: OSD size, OSD margins, etc.
void vo_get_src_dst_rects(struct vo *vo, struct mp_rect *out_src,
                          struct mp_rect *out_dst, struct mp_osd_res *out_osd)
{
    struct mp_vo_opts *opts = vo->opts;
    int src_w = vo->aspdat.orgw;
    int src_h = vo->aspdat.orgh;
    struct mp_rect dst = {0, 0, vo->dwidth, vo->dheight};
    struct mp_rect src = {0, 0, src_w,      src_h};
    struct mp_osd_res osd = {
        .w = vo->dwidth,
        .h = vo->dheight,
        .display_par = vo->aspdat.monitor_par,
        .video_par = vo->aspdat.par,
    };
    if (opts->keepaspect) {
        int scaled_width, scaled_height;
        aspect_calc_panscan(vo, &scaled_width, &scaled_height);
        src_dst_split_scaling(src_w, vo->dwidth, scaled_width, opts->unscaled,
                              opts->zoom, opts->align_x, opts->pan_x,
                              &src.x0, &src.x1, &dst.x0, &dst.x1,
                              &osd.ml, &osd.mr);
        src_dst_split_scaling(src_h, vo->dheight, scaled_height, opts->unscaled,
                              opts->zoom, opts->align_y, opts->pan_y,
                              &src.y0, &src.y1, &dst.y0, &dst.y1,
                              &osd.mt, &osd.mb);
    }

    *out_src = src;
    *out_dst = dst;
    *out_osd = osd;

    print_video_rect(vo, src, dst, osd);
}

// Return the window title the VO should set. Always returns a null terminated
// string. The string is valid until frontend code is invoked again. Copy it if
// you need to keep the string for an extended period of time.
const char *vo_get_window_title(struct vo *vo)
{
    if (!vo->window_title)
        vo->window_title = talloc_strdup(vo, "");
    return vo->window_title;
}

/**
 * Generates a mouse movement message if those are enable and sends it
 * to the "main" MPlayer.
 *
 * \param posx new x position of mouse
 * \param posy new y position of mouse
 */
void vo_mouse_movement(struct vo *vo, int posx, int posy)
{
    if (!vo->opts->enable_mouse_movements)
        return;
    float p[2] = {posx, posy};
    vo_control(vo, VOCTRL_WINDOW_TO_OSD_COORDS, p);
    mp_input_set_mouse_pos(vo->input_ctx, p[0], p[1]);
}