/*
 # This file is part of the Astrometry.net suite.
 # Licensed under a 3-clause BSD style license - see LICENSE
 */

#include <string.h>
#include <math.h>
#include <assert.h>

#include <cairo.h>

#include "os-features.h"
#include "plotannotations.h"
#include "hd.h"
#include "ngc2000.h"
#include "brightstars.h"
#include "cairoutils.h"
#include "sip-utils.h"
#include "starutil.h"
#include "ioutils.h"
#include "log.h"
#include "errors.h"
#include "sip-utils.h"
#include "mathutil.h"
#include "constellations.h"
#include "constellation-boundaries.h"

DEFINE_PLOTTER(annotations);

struct target {
    double ra;
    double dec;
    char* name;
};
typedef struct target target_t;

plotann_t* plot_annotations_get(plot_args_t* pargs) {
    return plotstuff_get_config(pargs, "annotations");
}

static void plot_targets(cairo_t* cairo, plot_args_t* pargs, plotann_t* ann) {
    int i;
    double cra, cdec;
    plotstuff_get_radec_center_and_radius(pargs, &cra, &cdec, NULL);
        
    for (i=0; i<bl_size(ann->targets); i++) {
        target_t* tar = bl_access(ann->targets, i);
        double px,py;
        double cx,cy;
        double dx,dy, r;
        double ex,ey;
        double ly, ry, tx, bx;
        double distdeg;
        anbool okquadrant;
        char* txt;

        logverb("Target: \"%s\" at (%g,%g)\n", tar->name, tar->ra, tar->dec);
        okquadrant = plotstuff_radec2xy(pargs, tar->ra, tar->dec, &px, &py);
        px -= 1;
        py -= 1;

        if (okquadrant &&
            px >= 0 && px < pargs->W && py >= 0 && py < pargs->H) {
            // inside the image!
            logverb("Target \"%s\" is inside the image, at pixel (%g,%g)\n", tar->name, px, py);
            plotstuff_stack_marker(pargs, px, py);
            plotstuff_stack_text(pargs, cairo, tar->name, px, py);
            continue;
        }

        // outside the image: find intersection point.
        cx = pargs->W / 2.0;
        cy = pargs->H / 2.0;
        if (okquadrant) {
            logverb("Target \"%s\" is outside the image, at pixel (%g,%g)\n", tar->name, px, py);
            dx = px - cx;
            dy = py - cy;
        } else {
            double cxyz[3];
            double txyz[3];
            double vec[3];
            int j;
            double ra,dec;
            logverb("Target \"%s\" is way outside the image.\n", tar->name);
            // fallback.
            radecdeg2xyzarr(cra, cdec, cxyz);
            radecdeg2xyzarr(tar->ra, tar->dec, txyz);
            for (j=0; j<3; j++)
                vec[j] = cxyz[j] + 0.1 * txyz[j];
            normalize_3(vec);
            xyzarr2radecdeg(vec, &ra, &dec);
            okquadrant = plotstuff_radec2xy(pargs, ra, dec, &px, &py);
            assert(okquadrant);
            dx = px - cx;
            dy = py - cy;
            if ((dx*dx + dy*dy) < (cx*cx + cy*cy)) {
                double scale = 3.0 * sqrt(cx*cx + cy*cy) / sqrt(dx*dx + dy*dy);
                dx *= scale;
                dy *= scale;
            }
        }

        ly = (-(pargs->W/2.0) / dx) * dy + cy;
        ry = ( (pargs->W/2.0) / dx) * dy + cy;
        bx = (-(pargs->H/2.0) / dy) * dx + cx;
        tx = ( (pargs->H/2.0) / dy) * dx + cx;
        logverb("ly %g, ry %g, bx %g, tx %g\n", ly, ry, bx, tx);
        if (px < cx && ly >= 0 && ly < pargs->H) {
            ex = 0.0;
            ey = ly;
        } else if (px >= cx && ry >= 0 && ry < pargs->H) {
            ex = pargs->W - 1;
            ey = ry;
        } else if (py < cy && bx >= 0 && bx < pargs->W) {
            ex = bx;
            ey = 0;
        } else if (py >= cy && tx >= 0 && tx < pargs->W) {
            ex = tx;
            ey = pargs->H - 1;
        } else {
            logverb("None of the edges are in bounds: px,py=(%g,%g); ly=%g, ry=%g, bx=%g, tx=%g\n", px,py,ly,ry,bx,tx);
            continue;
        }
        dx = ex - cx;
        dy = ey - cy;
        r = sqrt(dx*dx + dy*dy);

        px = (r-100.0) / r * dx + cx;
        py = (r-100.0) / r * dy + cy;

        plotstuff_stack_arrow(pargs, px, py, ex, ey);
        logverb("Arrow from (%g,%g) to (%g,%g)\n", px, py, ex, ey);
        distdeg = deg_between_radecdeg(cra, cdec, tar->ra, tar->dec);
        asprintf_safe(&txt, "%s: %.1f deg", tar->name, distdeg);
        plotstuff_stack_text(pargs, cairo, txt, px, py);
    }
}

static void plot_offset_line_rd(cairo_t* cairo, plot_args_t* pargs,
                                double r1, double d1,
                                double r2, double d2,
                                double offset1, double offset2) {
    double x1,x2,y1,y2;
    double dx, dy;
    double dist;
    double gapfrac;
    if (!cairo)
        cairo = pargs->cairo;
    if (!plotstuff_radec2xy(pargs, r1,d1, &x1,&y1) ||
        !plotstuff_radec2xy(pargs, r2,d2, &x2,&y2)) {
        ERROR("failed to convert RA,Dec to x,y for plotting line seg");
        return;
    }
    dx = x2 - x1;
    dy = y2 - y1;
    dist = hypot(dx, dy);
    gapfrac = offset1 / dist;
    //printf("(x1,y1)-(x2,y2) (%f, %f) -- (%f, %f)\n", x1,y1,x2,y2);
    //printf("Offset to:\n");
    //printf("                (%f, %f) -- ", x1 + dx*gapfrac, y1 + dy*gapfrac);
    cairo_move_to(cairo, x1 + dx*gapfrac, y1 + dy*gapfrac);
    gapfrac = offset2 / dist;
    cairo_line_to(cairo, x1 + dx*(1.0-gapfrac), y1 + dy*(1.0-gapfrac));
    //printf("(%f, %f)\n", x1 + dx*(1.0-gapfrac), y1 + dy*(1.0-gapfrac));
}

static void color_for_radec(double ra, double dec, float* r, float* g, float* b) {
    int con = constellation_containing(ra, dec);
    srand(con);
    *r = ((rand() % 128) + 127) / 255.0;
    *g = ((rand() % 128) + 127) / 255.0;
    *b = ((rand() % 128) + 127) / 255.0;
}

static void plot_constellations(cairo_t* cairo, plot_args_t* pargs, plotann_t* ann) {
    int i, N;
    double ra,dec,radius;
    double xyzf[3];
    // Find the field center and radius
    anwcs_get_radec_center_and_radius(pargs->wcs, &ra, &dec, &radius);
    logverb("Plotting constellations: field center %g,%g, radius %g\n",
            ra, dec, radius);
    radecdeg2xyzarr(ra, dec, xyzf);
    radius = deg2dist(radius);

    N = constellations_n();
    for (i=0; i<N; i++) {
        int j, k;
        // Find the approximate center and radius of this constellation
        // and see if it overlaps with the field.
        il* stars = constellations_get_unique_stars(i);
        double xyzj[3];
        double xyzc[3];
        double maxr2 = 0;
        dl* rds;
        xyzc[0] = xyzc[1] = xyzc[2] = 0.0;
        xyzj[0] = xyzj[1] = xyzj[2] = 0.0;
        for (j=0; j<il_size(stars); j++) {
            constellations_get_star_radec(il_get(stars, j), &ra, &dec);
            radecdeg2xyzarr(ra, dec, xyzj);
            for (k=0; k<3; k++)
                xyzc[k] += xyzj[k];
        }
        normalize_3(xyzc);
        for (j=0; j<il_size(stars); j++) {
            constellations_get_star_radec(il_get(stars, j), &ra, &dec);
            maxr2 = MAX(maxr2, distsq(xyzc, xyzj, 3));
        }
        il_free(stars);
        maxr2 = square(sqrt(maxr2) + radius);
        if (distsq(xyzf, xyzc, 3) > maxr2) {
            xyzarr2radecdeg(xyzc, &ra, &dec);
            logverb("Constellation %s (center %g,%g, radius %g) out of bounds\n",
                    constellations_get_shortname(i), ra, dec,
                    dist2deg(sqrt(maxr2) - radius));
            logverb("  dist from field center to constellation center is %g deg\n",
                    distsq2deg(distsq(xyzf, xyzc, 3)));
            logverb("  max radius: %g\n", distsq2deg(maxr2));
            continue;
        }

        if (ann->constellation_pastel) {
            float r,g,b;
            xyzarr2radecdeg(xyzc, &ra, &dec);
            color_for_radec(ra, dec, &r,&g,&b);
            plotstuff_set_rgba2(pargs, r,g,b, 0.8);
            plotstuff_builtin_apply(cairo, pargs);
        }

        // Phew, plot it.
        if (ann->constellation_lines) {
            rds = constellations_get_lines_radec(i);
            logverb("Constellation %s: plotting %zu lines\n",
                    constellations_get_shortname(i), dl_size(rds)/4);
            for (j=0; j<dl_size(rds)/4; j++) {
                double r1,d1,r2,d2;
                double r3,d3,r4,d4;
                double off = ann->constellation_lines_offset;
                r1 = dl_get(rds, j*4+0);
                d1 = dl_get(rds, j*4+1);
                r2 = dl_get(rds, j*4+2);
                d2 = dl_get(rds, j*4+3);
                if (anwcs_find_discontinuity(pargs->wcs, r1, d1, r2, d2,
                                             &r3, &d3, &r4, &d4)) {
                    logverb("Discontinuous: %g,%g -- %g,%g\n", r1, d1, r2, d2);
                    logverb("  %g,%g == %g,%g\n", r3,d3, r4,d4);
                    plot_offset_line_rd(NULL, pargs, r1,d1,r3,d3, off, 0.);
                    plot_offset_line_rd(NULL, pargs, r4,d4,r2,d2, 0., off);
                } else {
                    plot_offset_line_rd(NULL, pargs, r1,d1,r2,d2, off, off);
                }
                plotstuff_stroke(pargs);
            }
            dl_free(rds);
        }

        if (ann->constellation_labels ||
            ann->constellation_markers) {
            // Put the label at the center of mass of the stars that
            // are in-bounds
            int Nin = 0;
            stars = constellations_get_unique_stars(i);
            xyzc[0] = xyzc[1] = xyzc[2] = 0.0;
            logverb("Labeling %s: %zu stars\n", constellations_get_shortname(i),
                    il_size(stars));
            for (j=0; j<il_size(stars); j++) {
                constellations_get_star_radec(il_get(stars, j), &ra, &dec);
                if (!anwcs_radec_is_inside_image(pargs->wcs, ra, dec))
                    continue;
                if (ann->constellation_markers)
                    plotstuff_marker_radec(pargs, ra, dec);
                radecdeg2xyzarr(ra, dec, xyzj);
                for (k=0; k<3; k++)
                    xyzc[k] += xyzj[k];
                Nin++;
            }
            logverb("  %i stars in-bounds\n", Nin);
            if (ann->constellation_labels && Nin) {
                const char* label;
                normalize_3(xyzc);
                xyzarr2radecdeg(xyzc, &ra, &dec);
                if (ann->constellation_labels_long)
                    label = constellations_get_longname(i);
                else
                    label = constellations_get_shortname(i);
                plotstuff_text_radec(pargs, ra, dec, label);
            }
            il_free(stars);
        }
    }
}

static void plot_brightstars(cairo_t* cairo, plot_args_t* pargs, plotann_t* ann) {
    int i, N;

    // Get plot center, to use in trimming bright stars
    double rc,dc,radius;
    plotstuff_get_radec_center_and_radius(pargs, &rc, &dc, &radius);

    N = bright_stars_n();
    for (i=0; i<N; i++) {
        double px, py;
        char* label;
        const brightstar_t* bs = bright_stars_get(i);
        // skip unnamed
        if (!strlen(bs->name) && !strlen(bs->common_name))
            continue;
        // skip stars too far away
        if (deg_between_radecdeg(rc, dc, bs->ra, bs->dec) > radius * 1.2)
            continue;
        if (!plotstuff_radec2xy(pargs, bs->ra, bs->dec, &px, &py))
            continue;
        logverb("Bright star %s/%s at RA,Dec (%g,%g) -> xy (%g, %g)\n",
                bs->name, bs->common_name, bs->ra, bs->dec, px, py);
        if (px < 1 || py < 1 || px > pargs->W || py > pargs->H)
            continue;
        px -= 1;
        py -= 1;
        if (ann->bright_pastel) {
            float r,g,b;
            color_for_radec(bs->ra, bs->dec, &r,&g,&b);
            plotstuff_set_rgba2(pargs, r,g,b, 0.8);
            plotstuff_builtin_apply(cairo, pargs);
        }

        plotstuff_stack_marker(pargs, px, py);
        if (ann->bright_labels) {
            label = (strlen(bs->common_name) ? bs->common_name : bs->name);
            plotstuff_stack_text(pargs, cairo, label, px, py);
        }
    }
}

int plot_annotations_set_hd_catalog(plotann_t* ann, const char* hdfn) {
    if (ann->hd_catalog)
        free(ann->hd_catalog);
    ann->hd_catalog = strdup(hdfn);
    return 0;
}

static void plot_hd(cairo_t* cairo, plot_args_t* pargs, plotann_t* ann) {
    int i, N;
    hd_catalog_t* hdcat = NULL;
    double ra,dec,rad;
    bl* hdlist = NULL;

    if (!ann->hd_catalog)
        return;
    hdcat = henry_draper_open(ann->hd_catalog);
    if (!hdcat) {
        ERROR("Failed to open Henry Draper catalog file \"%s\"", ann->hd_catalog);
        return;
    }
    if (plotstuff_get_radec_center_and_radius(pargs, &ra, &dec, &rad)) {
        ERROR("Failed to get RA,Dec,radius from plotstuff");
        return;
    }
    hdlist = henry_draper_get(hdcat, ra, dec, deg2arcsec(rad));
    logverb("Got %zu Henry Draper stars\n", bl_size(hdlist));
        
    N = bl_size(hdlist);
    for (i=0; i<N; i++) {
        hd_entry_t* entry = bl_access(hdlist, i);
        double px, py;
        char label[16];
        if (!plotstuff_radec2xy(pargs, entry->ra, entry->dec, &px, &py))
            continue;
        px -= 1;
        py -= 1;

        if (px < 1 || py < 1 || px > pargs->W || py > pargs->H)
            continue;
        logverb("HD %i at RA,Dec (%g,%g) -> xy (%g, %g)\n", entry->hd, entry->ra, entry->dec, px, py);

        plotstuff_stack_marker(pargs, px, py);
        if (ann->HD_labels) {
            sprintf(label, "HD %i", entry->hd);
            plotstuff_stack_text(pargs, cairo, label, px, py);
        }
    }
    bl_free(hdlist);
    henry_draper_close(hdcat);
}

static void plot_ngc(cairo_t* cairo, plot_args_t* pargs, plotann_t* ann) {
    double imscale;
    double imsize;
    int i, N;

    // arcsec/pixel
    imscale = plotstuff_pixel_scale(pargs);
    // arcmin
    imsize = imscale * MIN(pargs->W, pargs->H) / 60.0;

    double ra_center, dec_center, radius_deg;

    // image RA,Dec center and radius, for quick filtering
    if (plotstuff_get_radec_center_and_radius(pargs, &ra_center, &dec_center,
                                              &radius_deg)) {
        logmsg("Error getting image RA,Dec center and radius");
        return;
    }
    // bit of margin
    radius_deg *= 1.1;

    N = ngc_num_entries();
    logverb("Checking %i NGC/IC objects.\n", N);

    for (i=0; i<N; i++) {
        ngc_entry* ngc;
        char* names;
        double pixrad;
        double px, py;
        double r;

        ngc = ngc_get_entry_accurate(i);
        if (!ngc)
            break;

        // Quick filter
        if (deg_between_radecdeg(ra_center, dec_center, ngc->ra, ngc->dec) > radius_deg)
            continue;

        if (ngc->size < imsize * ann->ngc_fraction) {
            // FIXME -- just plot an X-mark with label.
            debug("%s %i: size %g arcmin < limit of %g\n",
                  (ngc->is_ngc ? "NGC":"IC"), ngc->id, ngc->size, imsize*ann->ngc_fraction);
            continue;
        }

        if (!plotstuff_radec2xy(pargs, ngc->ra, ngc->dec, &px, &py)) {
            debug("%s %i: RA,Dec (%.1f,%.1f) is >90 deg away.\n",
                  (ngc->is_ngc ? "NGC":"IC"), ngc->id, ngc->ra, ngc->dec);
            continue;
        }
        px -= 1;
        py -= 1;

        pixrad = 0.5 * ngc->size * 60.0 / imscale;
        if (px < -pixrad || py < -pixrad || px > pargs->W + pixrad || py > pargs->H + pixrad) {
            debug("%s %i: RA,Dec (%.1f,%.1f), pix (%.1f,%.1f) is out-of-bounds\n",
                  (ngc->is_ngc ? "NGC":"IC"), ngc->id, ngc->ra, ngc->dec, px, py);
            continue;
        }

        names = ngc_get_name_list(ngc, " / ");
        printf("%s\n", names);

        logverb("%s %i: RA,Dec (%.1f,%.1f), size %g arcmin, pix (%.1f,%.1f), radius %g\n",
                (ngc->is_ngc ? "NGC":"IC"), ngc->id, ngc->ra, ngc->dec, ngc->size, px, py, pixrad);
        debug("size: %f arcsec, pix radius: %f pixels\n", ngc->size, pixrad);
        // save old marker size...
        r = pargs->markersize;
        pargs->markersize = pixrad;
        plotstuff_stack_marker(pargs, px, py);
        plotstuff_stack_text(pargs, cairo, names, px, py);
        free(names);
        // revert old marker size...
        pargs->markersize = r;

        /*
         if (json) {
         char* namelist = sl_implode(names, "\", \"");
         sl_appendf(json,
         "{ \"type\"   : \"ngc\", "
         "  \"names\"  : [ \"%s\" ], "
         "  \"pixelx\" : %g, "
         "  \"pixely\" : %g, "
         "  \"radius\" : %g }"
         , namelist, px, py, pixsize/2.0);
         free(namelist);
         }
         */
    }
}

void* plot_annotations_init(plot_args_t* args) {
    plotann_t* ann = calloc(1, sizeof(plotann_t));
    ann->ngc_fraction = 0.02;
    ann->targets = bl_new(4, sizeof(target_t));
    ann->NGC = TRUE;
    ann->bright = TRUE;
    ann->bright_labels = TRUE;
    ann->constellation_lines = TRUE;
    ann->constellation_lines_offset = 5.0;
    return ann;
}

int plot_annotations_plot(const char* cmd, cairo_t* cairo,
                          plot_args_t* pargs, void* baton) {
    plotann_t* ann = (plotann_t*)baton;

    // Set fonts, etc, before calling plotting routines
    plotstuff_builtin_apply(cairo, pargs);

    if (ann->NGC)
        plot_ngc(cairo, pargs, ann);

    if (ann->bright)
        plot_brightstars(cairo, pargs, ann);

    if (ann->HD)
        plot_hd(cairo, pargs, ann);

    if (ann->constellations)
        plot_constellations(cairo, pargs, ann);

    if (bl_size(ann->targets))
        plot_targets(cairo, pargs, ann);

    return plotstuff_plot_stack(pargs, cairo);
}

int plot_annotations_command(const char* cmd, const char* cmdargs,
                             plot_args_t* pargs, void* baton) {
    plotann_t* ann = (plotann_t*)baton;
    if (streq(cmd, "annotations_no_ngc")) {
        ann->NGC = FALSE;
    } else if (streq(cmd, "annotations_no_bright")) {
        ann->bright = FALSE;
    } else if (streq(cmd, "annotations_ngc_size")) {
        ann->ngc_fraction = atof(cmdargs);
    } else if (streq(cmd, "annotations_target")) {
        sl* args = sl_split(NULL, cmdargs, " ");
        double ra, dec;
        char* name;
        if (sl_size(args) != 3) {
            ERROR("Need RA,Dec,name");
            return -1;
        }
        ra = atof(sl_get(args, 0));
        dec = atof(sl_get(args, 1));
        name = sl_get(args, 2);
        plot_annotations_add_target(ann, ra, dec, name);
    } else if (streq(cmd, "annotations_targetname")) {
        const char* name = cmdargs;
        return plot_annotations_add_named_target(ann, name);
    } else {
        ERROR("Unknown command \"%s\"", cmd);
        return -1;
    }
    return 0;
}

int plot_annotations_add_named_target(plotann_t* ann, const char* name) {
    target_t tar;
    int i, N;
    // Try bright stars
    N = bright_stars_n();
    for (i=0; i<N; i++) {
        const brightstar_t* bs = bright_stars_get(i);
        if (!bs->name && !bs->common_name)
            continue;
        if (strcaseeq(name, bs->name) || strcaseeq(name, bs->common_name)) {
            tar.ra = bs->ra;
            tar.dec = bs->dec;
            if (strcaseeq(name, bs->name))
                tar.name = bs->name;
            else
                tar.name = bs->common_name;
            logmsg("Found %s: RA,Dec (%g,%g)\n", name, bs->ra, bs->dec);
            bl_append(ann->targets, &tar);
            return 0;
        }
    }
    // Try NGC objects
    ngc_entry* e = ngc_get_entry_named(name);
    if (!e) {
        ERROR("Failed to find target named \"%s\"", name);
        return -1;
    }
    tar.name = ngc_get_name_list(e, " / ");
    tar.ra = e->ra;
    tar.dec = e->dec;
    logmsg("Found %s: RA,Dec (%g,%g)\n", tar.name, tar.ra, tar.dec);
    bl_append(ann->targets, &tar);
    return 0;
}

void plot_annotations_add_target(plotann_t* ann, double ra, double dec,
                                 const char* name) {
    target_t tar;
    memset(&tar, 0, sizeof(target_t));
    tar.ra = ra;
    tar.dec = dec;
    tar.name = strdup(name);
    logmsg("Added target \"%s\" at (%g,%g)\n", tar.name, tar.ra, tar.dec);
    bl_append(ann->targets, &tar);
}

void plot_annotations_clear_targets(plotann_t* ann) {
    bl_remove_all(ann->targets);
}

void plot_annotations_free(plot_args_t* args, void* baton) {
    plotann_t* ann = (plotann_t*)baton;
    free(ann->hd_catalog);
    free(ann);
}