/*
 * Copyright 1998 by Egbert Eich <Egbert.Eich@Physik.TU-Darmstadt.DE>
 * Copyright 2007 Red Hat, Inc.
 *
 * 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 (including the next
 * paragraph) 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.
 *
 * interpret_edid.c: interpret a primary EDID block
 */

#ifdef HAVE_XORG_CONFIG_H
#include <xorg-config.h>
#endif

#include "misc.h"
#include "xf86.h"
#include "xf86_OSproc.h"
#define _PARSE_EDID_
#include "xf86DDC.h"
#include <string.h>

static void get_vendor_section(Uchar *, struct vendor *);
static void get_version_section(Uchar *, struct edid_version *);
static void get_display_section(Uchar *, struct disp_features *,
                                struct edid_version *);
static void get_established_timing_section(Uchar *,
                                           struct established_timings *);
static void get_std_timing_section(Uchar *, struct std_timings *,
                                   struct edid_version *);
static void fetch_detailed_block(Uchar * c, struct edid_version *ver,
                                 struct detailed_monitor_section *det_mon);
static void get_dt_md_section(Uchar *, struct edid_version *,
                              struct detailed_monitor_section *det_mon);
static void copy_string(Uchar *, Uchar *);
static void get_dst_timing_section(Uchar *, struct std_timings *,
                                   struct edid_version *);
static void get_monitor_ranges(Uchar *, struct monitor_ranges *);
static void get_whitepoint_section(Uchar *, struct whitePoints *);
static void get_detailed_timing_section(Uchar *, struct detailed_timings *);
static Bool validate_version(int scrnIndex, struct edid_version *);

static void
find_ranges_section(struct detailed_monitor_section *det, void *ranges)
{
    if (det->type == DS_RANGES && det->section.ranges.max_clock)
        *(struct monitor_ranges **) ranges = &det->section.ranges;
}

static void
find_max_detailed_clock(struct detailed_monitor_section *det, void *ret)
{
    if (det->type == DT) {
        *(int *) ret = max(*((int *) ret), det->section.d_timings.clock);
    }
}

static void
handle_edid_quirks(xf86MonPtr m)
{
    struct monitor_ranges *ranges = NULL;

    /*
     * max_clock is only encoded in EDID in tens of MHz, so occasionally we
     * find a monitor claiming a max of 160 with a mode requiring 162, or
     * similar.  Strictly we should refuse to round up too far, but let's
     * see how well this works.
     */

    /* Try to find Monitor Range and max clock, then re-set range value */
    xf86ForEachDetailedBlock(m, find_ranges_section, &ranges);
    if (ranges && ranges->max_clock) {
        int clock = 0;

        xf86ForEachDetailedBlock(m, find_max_detailed_clock, &clock);
        if (clock && (ranges->max_clock * 1e6 < clock)) {
            xf86Msg(X_WARNING, "EDID timing clock %.2f exceeds claimed max "
                    "%dMHz, fixing\n", clock / 1.0e6, ranges->max_clock);
            ranges->max_clock = (clock + 999999) / 1e6;
        }
    }
}

struct det_hv_parameter {
    int real_hsize;
    int real_vsize;
    float target_aspect;
};

static void
handle_detailed_hvsize(struct detailed_monitor_section *det_mon, void *data)
{
    struct det_hv_parameter *p = (struct det_hv_parameter *) data;
    float timing_aspect;

    if (det_mon->type == DT) {
        struct detailed_timings *timing;

        timing = &det_mon->section.d_timings;

        if (!timing->v_size)
            return;

        timing_aspect = (float) timing->h_size / timing->v_size;
        if (fabs(1 - (timing_aspect / p->target_aspect)) < 0.05) {
            p->real_hsize = max(p->real_hsize, timing->h_size);
            p->real_vsize = max(p->real_vsize, timing->v_size);
        }
    }
}

static void
encode_aspect_ratio(xf86MonPtr m)
{
    /*
     * some monitors encode the aspect ratio instead of the physical size.
     * try to find the largest detailed timing that matches that aspect
     * ratio and use that to fill in the feature section.
     */
    if ((m->features.hsize == 16 && m->features.vsize == 9) ||
        (m->features.hsize == 16 && m->features.vsize == 10) ||
        (m->features.hsize == 4 && m->features.vsize == 3) ||
        (m->features.hsize == 5 && m->features.vsize == 4)) {

        struct det_hv_parameter p;

        p.real_hsize = 0;
        p.real_vsize = 0;
        p.target_aspect = (float) m->features.hsize / m->features.vsize;

        xf86ForEachDetailedBlock(m, handle_detailed_hvsize, &p);

        if (!p.real_hsize || !p.real_vsize) {
            m->features.hsize = m->features.vsize = 0;
        }
        else if ((m->features.hsize * 10 == p.real_hsize) &&
                 (m->features.vsize * 10 == p.real_vsize)) {
            /* exact match is just unlikely, should do a better check though */
            m->features.hsize = m->features.vsize = 0;
        }
        else {
            /* convert mm to cm */
            m->features.hsize = (p.real_hsize + 5) / 10;
            m->features.vsize = (p.real_vsize + 5) / 10;
        }

        xf86Msg(X_INFO, "Quirked EDID physical size to %dx%d cm\n",
                m->features.hsize, m->features.vsize);
    }
}

xf86MonPtr
xf86InterpretEDID(int scrnIndex, Uchar * block)
{
    xf86MonPtr m;

    if (!block)
        return NULL;
    if (!(m = xnfcalloc(sizeof(xf86Monitor), 1)))
        return NULL;
    m->scrnIndex = scrnIndex;
    m->rawData = block;

    get_vendor_section(SECTION(VENDOR_SECTION, block), &m->vendor);
    get_version_section(SECTION(VERSION_SECTION, block), &m->ver);
    if (!validate_version(scrnIndex, &m->ver))
        goto error;
    get_display_section(SECTION(DISPLAY_SECTION, block), &m->features, &m->ver);
    get_established_timing_section(SECTION(ESTABLISHED_TIMING_SECTION, block),
                                   &m->timings1);
    get_std_timing_section(SECTION(STD_TIMING_SECTION, block), m->timings2,
                           &m->ver);
    get_dt_md_section(SECTION(DET_TIMING_SECTION, block), &m->ver, m->det_mon);
    m->no_sections = (int) *(char *) SECTION(NO_EDID, block);

    handle_edid_quirks(m);
    encode_aspect_ratio(m);

    return m;

 error:
    free(m);
    return NULL;
}

static int
get_cea_detail_timing(Uchar * blk, xf86MonPtr mon,
                      struct detailed_monitor_section *det_mon)
{
    int dt_num;
    int dt_offset = ((struct cea_ext_body *) blk)->dt_offset;

    dt_num = 0;

    if (dt_offset < CEA_EXT_MIN_DATA_OFFSET)
        return dt_num;

    for (; dt_offset < (CEA_EXT_MAX_DATA_OFFSET - DET_TIMING_INFO_LEN) &&
         dt_num < CEA_EXT_DET_TIMING_NUM; _NEXT_DT_MD_SECTION(dt_offset)) {

        fetch_detailed_block(blk + dt_offset, &mon->ver, det_mon + dt_num);
        dt_num = dt_num + 1;
    }

    return dt_num;
}

static void
handle_cea_detail_block(Uchar * ext, xf86MonPtr mon,
                        handle_detailed_fn fn, void *data)
{
    int i;
    struct detailed_monitor_section det_mon[CEA_EXT_DET_TIMING_NUM];
    int det_mon_num;

    det_mon_num = get_cea_detail_timing(ext, mon, det_mon);

    for (i = 0; i < det_mon_num; i++)
        fn(det_mon + i, data);
}

void
xf86ForEachDetailedBlock(xf86MonPtr mon, handle_detailed_fn fn, void *data)
{
    int i;
    Uchar *ext;

    if (mon == NULL)
        return;

    for (i = 0; i < DET_TIMINGS; i++)
        fn(mon->det_mon + i, data);

    for (i = 0; i < mon->no_sections; i++) {
        ext = mon->rawData + EDID1_LEN * (i + 1);
        switch (ext[EXT_TAG]) {
        case CEA_EXT:
            handle_cea_detail_block(ext, mon, fn, data);
            break;
        case VTB_EXT:
        case DI_EXT:
        case LS_EXT:
        case MI_EXT:
            break;
        }
    }
}

static struct cea_data_block *
extract_cea_data_block(Uchar * ext, int data_type)
{
    struct cea_ext_body *cea;
    struct cea_data_block *data_collection;
    struct cea_data_block *data_end;

    cea = (struct cea_ext_body *) ext;

    if (cea->dt_offset <= CEA_EXT_MIN_DATA_OFFSET)
        return NULL;

    data_collection = &cea->data_collection;
    data_end = (struct cea_data_block *) (cea->dt_offset + ext);

    for (; data_collection < data_end;) {

        if (data_type == data_collection->tag) {
            return data_collection;
        }
        data_collection = (void *) ((unsigned char *) data_collection +
                                    data_collection->len + 1);
    }

    return NULL;
}

static void
handle_cea_video_block(Uchar * ext, handle_video_fn fn, void *data)
{
    struct cea_video_block *video;
    struct cea_video_block *video_end;
    struct cea_data_block *data_collection;

    data_collection = extract_cea_data_block(ext, CEA_VIDEO_BLK);
    if (data_collection == NULL)
        return;

    video = &data_collection->u.video;
    video_end = (struct cea_video_block *)
        ((Uchar *) video + data_collection->len);

    for (; video < video_end; video = video + 1) {
        fn(video, data);
    }
}

void
xf86ForEachVideoBlock(xf86MonPtr mon, handle_video_fn fn, void *data)
{
    int i;
    Uchar *ext;

    if (mon == NULL)
        return;

    for (i = 0; i < mon->no_sections; i++) {
        ext = mon->rawData + EDID1_LEN * (i + 1);
        switch (ext[EXT_TAG]) {
        case CEA_EXT:
            handle_cea_video_block(ext, fn, data);
            break;
        case VTB_EXT:
        case DI_EXT:
        case LS_EXT:
        case MI_EXT:
            break;
        }
    }
}

static Bool
cea_db_offsets(Uchar *cea, int *start, int *end)
{
    /* Data block offset in CEA extension block */
    *start = CEA_EXT_MIN_DATA_OFFSET;
    *end = cea[2];
    if (*end == 0)
        *end = CEA_EXT_MAX_DATA_OFFSET;
    if (*end < CEA_EXT_MIN_DATA_OFFSET || *end > CEA_EXT_MAX_DATA_OFFSET)
        return FALSE;
    return TRUE;
}

static int
cea_db_len(Uchar *db)
{
    return db[0] & 0x1f;
}

static int
cea_db_tag(Uchar *db)
{
    return db[0] >> 5;
}

typedef void (*handle_cea_db_fn) (Uchar *, void *);

static void
cea_for_each_db(xf86MonPtr mon, handle_cea_db_fn fn, void *data)
{
    int i;

    if (!mon)
        return;

    if (!(mon->flags & EDID_COMPLETE_RAWDATA))
        return;

    if (!mon->no_sections)
        return;

    if (!mon->rawData)
        return;

    for (i = 0; i < mon->no_sections; i++) {
        int start, end, offset;
        Uchar *ext;

        ext = mon->rawData + EDID1_LEN * (i + 1);
        if (ext[EXT_TAG] != CEA_EXT)
            continue;

        if (!cea_db_offsets(ext, &start, &end))
            continue;

        for (offset = start;
             offset < end && offset + cea_db_len(&ext[offset]) < end;
             offset += cea_db_len(&ext[offset]) + 1)
                fn(&ext[offset], data);
    }
}

struct find_hdmi_block_data {
    struct cea_data_block *hdmi;
};

static void find_hdmi_block(Uchar *db, void *data)
{
    struct find_hdmi_block_data *result = data;
    int oui;

    if (cea_db_tag(db) != CEA_VENDOR_BLK)
        return;

    if (cea_db_len(db) < 5)
        return;

    oui = (db[3] << 16) | (db[2] << 8) | db[1];
    if (oui == IEEE_ID_HDMI)
        result->hdmi = (struct cea_data_block *)db;
}

struct cea_data_block *xf86MonitorFindHDMIBlock(xf86MonPtr mon)
{
    struct find_hdmi_block_data result = { NULL };

    cea_for_each_db(mon, find_hdmi_block, &result);

    return result.hdmi;
}

xf86MonPtr
xf86InterpretEEDID(int scrnIndex, Uchar * block)
{
    xf86MonPtr m;

    m = xf86InterpretEDID(scrnIndex, block);
    if (!m)
        return NULL;

    /* extension parse */

    return m;
}

static void
get_vendor_section(Uchar * c, struct vendor *r)
{
    r->name[0] = L1;
    r->name[1] = L2;
    r->name[2] = L3;
    r->name[3] = '\0';

    r->prod_id = PROD_ID;
    r->serial = SERIAL_NO;
    r->week = WEEK;
    r->year = YEAR;
}

static void
get_version_section(Uchar * c, struct edid_version *r)
{
    r->version = VERSION;
    r->revision = REVISION;
}

static void
get_display_section(Uchar * c, struct disp_features *r, struct edid_version *v)
{
    r->input_type = INPUT_TYPE;
    if (!DIGITAL(r->input_type)) {
        r->input_voltage = INPUT_VOLTAGE;
        r->input_setup = SETUP;
        r->input_sync = SYNC;
    }
    else if (v->revision == 2 || v->revision == 3) {
        r->input_dfp = DFP;
    }
    else if (v->revision >= 4) {
        r->input_bpc = BPC;
        r->input_interface = DIGITAL_INTERFACE;
    }
    r->hsize = HSIZE_MAX;
    r->vsize = VSIZE_MAX;
    r->gamma = GAMMA;
    r->dpms = DPMS;
    r->display_type = DISPLAY_TYPE;
    r->msc = MSC;
    r->redx = REDX;
    r->redy = REDY;
    r->greenx = GREENX;
    r->greeny = GREENY;
    r->bluex = BLUEX;
    r->bluey = BLUEY;
    r->whitex = WHITEX;
    r->whitey = WHITEY;
}

static void
get_established_timing_section(Uchar * c, struct established_timings *r)
{
    r->t1 = T1;
    r->t2 = T2;
    r->t_manu = T_MANU;
}

static void
get_cvt_timing_section(Uchar * c, struct cvt_timings *r)
{
    int i;

    for (i = 0; i < 4; i++) {
        if (c[0] && c[1] && c[2]) {
            r[i].height = (c[0] + ((c[1] & 0xF0) << 8) + 1) * 2;
            switch (c[1] & 0xc0) {
            case 0x00:
                r[i].width = r[i].height * 4 / 3;
                break;
            case 0x40:
                r[i].width = r[i].height * 16 / 9;
                break;
            case 0x80:
                r[i].width = r[i].height * 16 / 10;
                break;
            case 0xc0:
                r[i].width = r[i].height * 15 / 9;
                break;
            }
            switch (c[2] & 0x60) {
            case 0x00:
                r[i].rate = 50;
                break;
            case 0x20:
                r[i].rate = 60;
                break;
            case 0x40:
                r[i].rate = 75;
                break;
            case 0x60:
                r[i].rate = 85;
                break;
            }
            r[i].rates = c[2] & 0x1f;
        }
        else {
            return;
        }
        c += 3;
    }
}

static void
get_std_timing_section(Uchar * c, struct std_timings *r, struct edid_version *v)
{
    int i;

    for (i = 0; i < STD_TIMINGS; i++) {
        if (VALID_TIMING) {
            r[i].hsize = HSIZE1;
            VSIZE1(r[i].vsize);
            r[i].refresh = REFRESH_R;
            r[i].id = STD_TIMING_ID;
        }
        else {
            r[i].hsize = r[i].vsize = r[i].refresh = r[i].id = 0;
        }
        NEXT_STD_TIMING;
    }
}

static const unsigned char empty_block[18];

static void
fetch_detailed_block(Uchar * c, struct edid_version *ver,
                     struct detailed_monitor_section *det_mon)
{
    if (ver->version == 1 && ver->revision >= 1 && IS_MONITOR_DESC) {
        switch (MONITOR_DESC_TYPE) {
        case SERIAL_NUMBER:
            det_mon->type = DS_SERIAL;
            copy_string(c, det_mon->section.serial);
            break;
        case ASCII_STR:
            det_mon->type = DS_ASCII_STR;
            copy_string(c, det_mon->section.ascii_data);
            break;
        case MONITOR_RANGES:
            det_mon->type = DS_RANGES;
            get_monitor_ranges(c, &det_mon->section.ranges);
            break;
        case MONITOR_NAME:
            det_mon->type = DS_NAME;
            copy_string(c, det_mon->section.name);
            break;
        case ADD_COLOR_POINT:
            det_mon->type = DS_WHITE_P;
            get_whitepoint_section(c, det_mon->section.wp);
            break;
        case ADD_STD_TIMINGS:
            det_mon->type = DS_STD_TIMINGS;
            get_dst_timing_section(c, det_mon->section.std_t, ver);
            break;
        case COLOR_MANAGEMENT_DATA:
            det_mon->type = DS_CMD;
            break;
        case CVT_3BYTE_DATA:
            det_mon->type = DS_CVT;
            get_cvt_timing_section(c, det_mon->section.cvt);
            break;
        case ADD_EST_TIMINGS:
            det_mon->type = DS_EST_III;
            memcpy(det_mon->section.est_iii, c + 6, 6);
            break;
        case ADD_DUMMY:
            det_mon->type = DS_DUMMY;
            break;
        default:
            det_mon->type = DS_UNKOWN;
            break;
        }
        if (c[3] <= 0x0F && memcmp(c, empty_block, sizeof(empty_block))) {
            det_mon->type = DS_VENDOR + c[3];
        }
    }
    else {
        det_mon->type = DT;
        get_detailed_timing_section(c, &det_mon->section.d_timings);
    }
}

static void
get_dt_md_section(Uchar * c, struct edid_version *ver,
                  struct detailed_monitor_section *det_mon)
{
    int i;

    for (i = 0; i < DET_TIMINGS; i++) {
        fetch_detailed_block(c, ver, det_mon + i);
        NEXT_DT_MD_SECTION;
    }
}

static void
copy_string(Uchar * c, Uchar * s)
{
    int i;

    c = c + 5;
    for (i = 0; (i < 13 && *c != 0x0A); i++)
        *(s++) = *(c++);
    *s = 0;
    while (i-- && (*--s == 0x20))
        *s = 0;
}

static void
get_dst_timing_section(Uchar * c, struct std_timings *t, struct edid_version *v)
{
    int j;

    c = c + 5;
    for (j = 0; j < 5; j++) {
        t[j].hsize = HSIZE1;
        VSIZE1(t[j].vsize);
        t[j].refresh = REFRESH_R;
        t[j].id = STD_TIMING_ID;
        NEXT_STD_TIMING;
    }
}

static void
get_monitor_ranges(Uchar * c, struct monitor_ranges *r)
{
    r->min_v = MIN_V;
    r->max_v = MAX_V;
    r->min_h = MIN_H;
    r->max_h = MAX_H;
    r->max_clock = 0;
    if (MAX_CLOCK != 0xff)      /* is specified? */
        r->max_clock = MAX_CLOCK * 10 + 5;
    if (HAVE_2ND_GTF) {
        r->gtf_2nd_f = F_2ND_GTF;
        r->gtf_2nd_c = C_2ND_GTF;
        r->gtf_2nd_m = M_2ND_GTF;
        r->gtf_2nd_k = K_2ND_GTF;
        r->gtf_2nd_j = J_2ND_GTF;
    }
    else {
        r->gtf_2nd_f = 0;
    }
    if (HAVE_CVT) {
        r->max_clock_khz = MAX_CLOCK_KHZ;
        r->max_clock = r->max_clock_khz / 1000;
        r->maxwidth = MAXWIDTH;
        r->supported_aspect = SUPPORTED_ASPECT;
        r->preferred_aspect = PREFERRED_ASPECT;
        r->supported_blanking = SUPPORTED_BLANKING;
        r->supported_scaling = SUPPORTED_SCALING;
        r->preferred_refresh = PREFERRED_REFRESH;
    }
    else {
        r->max_clock_khz = 0;
    }
}

static void
get_whitepoint_section(Uchar * c, struct whitePoints *wp)
{
    wp[0].white_x = WHITEX1;
    wp[0].white_y = WHITEY1;
    wp[1].white_x = WHITEX2;
    wp[1].white_y = WHITEY2;
    wp[0].index = WHITE_INDEX1;
    wp[1].index = WHITE_INDEX2;
    wp[0].white_gamma = WHITE_GAMMA1;
    wp[1].white_gamma = WHITE_GAMMA2;
}

static void
get_detailed_timing_section(Uchar * c, struct detailed_timings *r)
{
    r->clock = PIXEL_CLOCK;
    r->h_active = H_ACTIVE;
    r->h_blanking = H_BLANK;
    r->v_active = V_ACTIVE;
    r->v_blanking = V_BLANK;
    r->h_sync_off = H_SYNC_OFF;
    r->h_sync_width = H_SYNC_WIDTH;
    r->v_sync_off = V_SYNC_OFF;
    r->v_sync_width = V_SYNC_WIDTH;
    r->h_size = H_SIZE;
    r->v_size = V_SIZE;
    r->h_border = H_BORDER;
    r->v_border = V_BORDER;
    r->interlaced = INTERLACED;
    r->stereo = STEREO;
    r->stereo_1 = STEREO1;
    r->sync = SYNC_T;
    r->misc = MISC;
}

#define MAX_EDID_MINOR 4

static Bool
validate_version(int scrnIndex, struct edid_version *r)
{
    if (r->version != 1) {
        xf86DrvMsg(scrnIndex, X_ERROR, "Unknown EDID version %d\n", r->version);
        return FALSE;
    }

    if (r->revision > MAX_EDID_MINOR)
        xf86DrvMsg(scrnIndex, X_WARNING,
                   "Assuming version 1.%d is compatible with 1.%d\n",
                   r->revision, MAX_EDID_MINOR);

    return TRUE;
}

/*
 * Returns true if HDMI, false if definitely not or unknown.
 */
Bool
xf86MonitorIsHDMI(xf86MonPtr mon)
{
    return xf86MonitorFindHDMIBlock(mon) != NULL;
}