source/sargasso2/sargasso.c

/*
 * This file is part of Sargasso, http://zamez.org/sargasso
 * Licensed under the GNU General Public License,
 *                http://www.opensource.org/licenses/gpl-license
 * Copyright 2006 James Bursa <james@zamez.org>
 */

#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <oslib/colourtrans.h>
#include <oslib/osfile.h>
#include <oslib/uri.h>
#include <oslib/wimp.h>
#include <oslib/wimpspriteop.h>
#include <rufl.h>
#include "feed.h"


#define MAX_LINES 20
#define MARGIN 10
#define FEEDS_READ "Choices:Sargasso.Feeds"
#define FEEDS_WRITE "<Choices$Write>.Sargasso.Feeds"
#define CHOICES_READ "Choices:Sargasso.Choices"
#define CHOICES_WRITE "<Choices$Write>.Sargasso.Choices"
#define WRITE_DIR "<Choices$Write>.Sargasso"

#define LOG(x) (printf(__FILE__ " %s %i: ", __PRETTY_FUNCTION__, __LINE__), printf x, fputc('\n', stdout));

typedef void (*click_callback)(unsigned int i);

struct paragraph {
        int x0, y0, x1, y1;
        int background, colour;
        const char *font_family;
        rufl_style font_style;
        unsigned int font_size;
        click_callback click;
        unsigned int click_i;
        unsigned int lines;
        const char *text[MAX_LINES + 1];
        struct paragraph *next;
};

bool quit = false;
int interval = 30 * 60;
os_t last_update = 0;

wimp_t task;
wimp_w info_window, main_window, feed_window, add_feed_window,
                warning_window = 0, choices_window;
osspriteop_area *sprites;
struct paragraph *main_window_paragraphs = 0;
struct paragraph *feed_window_paragraphs = 0;
unsigned int current_feed = 0;
char font_headings[100] = "Homerton";
char font_summaries[100] = "NewHall";
char font_links[100] = "Homerton";

#define ICON_FLAGS (wimp_ICON_TEXT | \
                (wimp_COLOUR_BLACK << wimp_ICON_FG_COLOUR_SHIFT))
wimp_MENU(4) iconbar_menu = { { "Sargasso" }, wimp_COLOUR_BLACK,
        wimp_COLOUR_LIGHT_GREY, wimp_COLOUR_BLACK, wimp_COLOUR_WHITE,
        200, 44, 0,
        { { 0, 0, ICON_FLAGS, { "Info" } },
          { 0, 0, ICON_FLAGS, { "Choices..." } },
          { 0, 0, ICON_FLAGS, { "Update feeds" } },
          { wimp_MENU_LAST, 0, ICON_FLAGS, { "Quit" } } } };
wimp_MENU(2) main_menu = { { "Sargasso" }, wimp_COLOUR_BLACK,
        wimp_COLOUR_LIGHT_GREY, wimp_COLOUR_BLACK, wimp_COLOUR_WHITE,
        200, 44, 0,
        { { 0, 0, ICON_FLAGS, { "Add feed..." } },
          { wimp_MENU_LAST, 0, ICON_FLAGS, { "Remove feed" } } } };
wimp_menu *current_menu;
unsigned int current_removing = 0;
wimp_i current_font_menu;

const char *default_feeds[] = {
        "http://news.google.co.uk/?output=rss",
        "http://www.ft.com/rss/home/uk",
        "http://newsrss.bbc.co.uk/rss/newsonline_uk_edition/front_page/rss.xml",
        "http://rss.cnn.com/rss/edition.rss",
        "http://feeds.chicagotribune.com/chicagotribune/news/",
        "http://www.drobe.co.uk/rss.php",
        "http://www.theregister.co.uk/feeds/latest.rdf",
        "http://www.snackspot.org.uk/rss/rss.xml",
        "http://www.mode7games.com/blog/?feed=rss2",
        "http://cia.navi.cx/stats/project/NetSurf/.rss",
};

void gui_init(void);
void gui_quit(void);
wimp_w create_window(const char *name);
void gui_poll(void);
void mouse_click(wimp_w w, wimp_i i, int x, int y,
                wimp_mouse_state buttons);
void set_pointer(const char *name, int x, int y);
void reset_pointer(void);
void key_pressed(wimp_key *key);
void menu_selection(wimp_selection *selection);
void open_window(wimp_w w);
void close_window(wimp_w w);
void open_menu(wimp_menu *menu, int x, int y);
void update_main_window(void);
void set_extent(wimp_w w, int y);
void click_main_window(unsigned int i);
void update_feed_window(unsigned int i);
void click_feed_link(unsigned int i);
void click_item_link(unsigned int j);
struct paragraph *add_paragraph(struct paragraph **paragraph_list,
                int x0, int y0, int x1, int background, int colour,
                const char *font_family, rufl_style font_style,
                unsigned int font_size, const char *text,
                click_callback click, unsigned int click_i);
void free_paragraph_list(struct paragraph **paragraph_list);
void redraw_window(wimp_draw *redraw, struct paragraph *paragraphs);
void fill_rectangle(int x0, int y0, int x1, int y1, int colour);
void choices_save(void);
void choices_load(void);
void die(const char *error);
void warn(const char *warning);
char *get_icon_string(wimp_w w, wimp_i i);
void set_icon_string(wimp_w w, wimp_i i, const char *text);


int main(int argc, char *argv[])
{
        char error[200];
        struct stat s;

/*      memdebug_memdebug("memdump"); */

        if (!feed_init())
                die(feed_error);

        interval = (30 + time(0) % 20) * 60;
        choices_load();
        gui_init();

        if (stat(FEEDS_READ, &s)) {
                warn("Welcome to Sargasso! A selection of feeds have been "
                                "added. To add more feeds, use the main menu.");
                mkdir(WRITE_DIR, S_IRWXU);
                for (unsigned int i = 0; i != sizeof default_feeds /
                                sizeof default_feeds[0]; i++)
                        feed_add(default_feeds[i]);
                feed_list_save(FEEDS_WRITE);
        } else if (!feed_list_load(FEEDS_READ)) {
                snprintf(error, sizeof error, "Unable to load feed list: %s",
                                feed_error);
                warn(error);
        }

        update_main_window();
        open_window(main_window);

        last_update = os_read_monotonic_time();

        while (!quit)
                gui_poll();

        gui_quit();
        feed_quit();

        return 0;
}


void gui_init(void)
{
        rufl_code code;
        const wimp_MESSAGE_LIST(1) messages = { { message_QUIT } };
        int size;
        fileswitch_object_type obj_type;
        wimp_icon_create icon = {
                wimp_ICON_BAR_RIGHT,
                { { 0, 0, 68, 68 },
                wimp_ICON_SPRITE | wimp_ICON_HCENTRED | wimp_ICON_VCENTRED |
                        (wimp_BUTTON_CLICK << wimp_ICON_BUTTON_TYPE_SHIFT),
                { "!sargasso" } } };
        os_error *error;

        error = xwimp_initialise(wimp_VERSION_RO3, "Sargasso",
                        (const wimp_message_list *) &messages, 0, &task);
        if (error) {
                LOG(("xwimp_initialise: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }

        code = rufl_init();
        if (code != rufl_OK) {
                LOG(("rufl_init: %i", code));
                die("Failed to initialise Unicode font library");
        }

        error = xosfile_read_stamped_no_path("<Sargasso$Dir>.Sprites",
                        &obj_type, 0, 0, &size, 0, 0);
        if (error) {
                LOG(("xosfile_read_stamped_no_path: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }
        if (obj_type != fileswitch_IS_FILE)
                die("Sprites file missing");
        sprites = malloc(size + 4);
        if (!sprites)
                die("Out of memory");
        sprites->size = size + 4;
        sprites->sprite_count = 0;
        sprites->first = 16;
        sprites->used = 16;
        error = xosspriteop_load_sprite_file(osspriteop_USER_AREA,
                        sprites, "<Sargasso$Dir>.Sprites");
        if (error) {
                LOG(("xosspriteop_load_sprite_file: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }

        error = xwimp_create_icon(&icon, 0);
        if (error) {
                LOG(("xwimp_create_icon: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }

        error = xwimp_open_template("<Sargasso$Dir>.Templates");
        if (error) {
                LOG(("xwimp_open_template: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }

        info_window = create_window("info");
        main_window = create_window("main");
        feed_window = create_window("main");
        add_feed_window = create_window("add_feed");
        warning_window = create_window("warning");
        choices_window = create_window("choices");

        iconbar_menu.entries[0].sub_menu = (wimp_menu *) info_window;

        error = xwimp_close_template();
        if (error) {
                LOG(("xwimp_close_template: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }
}


void gui_quit(void)
{
        free_paragraph_list(&main_window_paragraphs);
        free_paragraph_list(&feed_window_paragraphs);
        rufl_quit();
}


wimp_w create_window(const char *name)
{
        char name_buf[12];
        int window_size;
        int data_size;
        wimp_window *window;
        char *data;
        wimp_w w;
        os_error *error;

        assert(strlen(name) < 12);

        strncpy(name_buf, name, sizeof name_buf);

        error = xwimp_load_template(wimp_GET_SIZE, 0, 0, wimp_NO_FONTS,
                        name_buf, 0, &window_size, &data_size, 0);
        if (error) {
                LOG(("xwimp_load_template: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }

        window = malloc(window_size);
        data = malloc(data_size);
        if (!window || !data)
                die("Out of memory");

        error = xwimp_load_template(window, data, data + data_size,
                        wimp_NO_FONTS, name_buf, 0, 0, 0, 0);
        if (error) {
                LOG(("xwimp_load_template: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }

        error = xwimp_create_window(window, &w);
        if (error) {
                LOG(("xwimp_create_window: 0x%x: %s",
                                error->errnum, error->errmess));
                die(error->errmess);
        }

        return w;
}


void gui_poll(void)
{
        static bool in_window = false;
        os_t t;
        wimp_block block;
        wimp_event_no event;
        wimp_pointer pointer;
        osbool more;
        os_error *error;

        t = os_read_monotonic_time();

        error = xwimp_poll_idle(0,
                        &block,
                        feed_work_needed || in_window ? t + 5 : t + 100,
                        0, &event);
        if (error) {
                LOG(("xwimp_poll: 0x%x: %s", error->errnum, error->errmess));
                warn(error->errmess);
        }

        switch (event) {
        case wimp_NULL_REASON_CODE:
                if (feed_work_needed) {
                        if (feed_work()) {
                                update_main_window();
                                if (feed_count && feeds[current_feed].updated)
                                        update_feed_window(current_feed);
                        }
                }

                t = os_read_monotonic_time();
                if (last_update + interval * 100 <= t) {
                        LOG(("updating"));
                        last_update = t;
                        feed_update();
                }

                error = xwimp_get_pointer_info(&pointer);
                if (error) {
                        LOG(("xwimp_get_pointer_info: 0x%x: %s",
                                        error->errnum, error->errmess));
                        warn(error->errmess);
                }
                mouse_click(pointer.w, pointer.i,
                                pointer.pos.x, pointer.pos.y, 0);
                break;

        case wimp_REDRAW_WINDOW_REQUEST:
                error = xwimp_redraw_window(&block.redraw, &more);
                if (error) {
                        LOG(("xwimp_redraw_window: 0x%x: %s",
                                        error->errnum, error->errmess));
                        break;
                }
                while (more) {
                        if (block.redraw.w == main_window)
                                redraw_window(&block.redraw,
                                                main_window_paragraphs);
                        else if (block.redraw.w == feed_window)
                                redraw_window(&block.redraw,
                                                feed_window_paragraphs);
                        error = xwimp_get_rectangle(&block.redraw, &more);
                        if (error) {
                                LOG(("xwimp_get_rectangle: 0x%x: %s",
                                                error->errnum, error->errmess));
                                break;
                        }
                }
                break;

        case wimp_OPEN_WINDOW_REQUEST:
                error = xwimp_open_window(&block.open);
                if (error) {
                        LOG(("xwimp_open_window: 0x%x: %s",
                                        error->errnum, error->errmess));
                        warn(error->errmess);
                }
                break;

        case wimp_CLOSE_WINDOW_REQUEST:
                error = xwimp_close_window(block.close.w);
                if (error) {
                        LOG(("xwimp_close_window: 0x%x: %s",
                                        error->errnum, error->errmess));
                        warn(error->errmess);
                }
                break;

        case wimp_POINTER_LEAVING_WINDOW:
                reset_pointer();
                in_window = false;
                break;

        case wimp_POINTER_ENTERING_WINDOW:
                in_window = true;
                break;

        case wimp_MOUSE_CLICK:
                mouse_click(block.pointer.w, block.pointer.i,
                                block.pointer.pos.x, block.pointer.pos.y,
                                block.pointer.buttons);
                break;

        case wimp_KEY_PRESSED:
                key_pressed(&block.key);
                break;

        case wimp_MENU_SELECTION:
                menu_selection(&block.selection);
                break;

        case wimp_USER_MESSAGE:
        case wimp_USER_MESSAGE_RECORDED:
                switch (block.message.action) {
                case message_QUIT:
                        quit = true;
                        break;
                }
                break;
        }
}


void mouse_click(wimp_w w, wimp_i i, int x, int y,
                wimp_mouse_state buttons)
{
        wimp_window_state state;
        int wx, wy;
        struct paragraph *p = 0;
        char minutes[10];
        int mins;
        os_error *error;

        if (w == wimp_ICON_BAR) {
                if (buttons == wimp_CLICK_MENU)
                        open_menu((wimp_menu *) &iconbar_menu,
                                        x - 64, 96 + 44 * 4);
                else if (buttons == wimp_CLICK_SELECT ||
                                buttons == wimp_CLICK_ADJUST)
                        open_window(main_window);

        } else if (w == main_window || w == feed_window) {
                state.w = w;
                error = xwimp_get_window_state(&state);
                if (error) {
                        LOG(("xwimp_get_window_state: 0x%x: %s",
                                        error->errnum, error->errmess));
                        warn(error->errmess);
                }
                wx = x - (state.visible.x0 - state.xscroll);
                wy = -(y - (state.visible.y1 - state.yscroll));
                if (w == main_window)
                        p = main_window_paragraphs;
                else
                        p = feed_window_paragraphs;
                for (; p; p = p->next) {
                        if (p->x0 <= wx && wx <= p->x1 &&
                                        p->y0 <= wy && wy <= p->y1 &&
                                        p->click)
                                break;
                }
                if (p && buttons == wimp_CLICK_SELECT)
                        p->click(p->click_i);
                else if (buttons == wimp_CLICK_MENU &&
                                w == main_window) {
                        if (p)
                                main_menu.entries[1].icon_flags &=
                                                ~wimp_ICON_SHADED;
                        else
                                main_menu.entries[1].icon_flags |=
                                                wimp_ICON_SHADED;
                        open_menu((wimp_menu *) &main_menu, x - 64, y);
                        current_removing = p ? p->click_i : 0;
                } else if (buttons == 0) {
                        if (p)
                                set_pointer("ptr_point", 6, 0);
                        else
                                reset_pointer();
                }

        } else if (w == add_feed_window && buttons) {
                if (i == 1) {
                        feed_add(get_icon_string(add_feed_window, 0));
                        update_main_window();
                        if (!feed_list_save(FEEDS_WRITE))
                                warn(feed_error);
                        if (buttons == wimp_CLICK_SELECT)
                                close_window(add_feed_window);
                } else if (i == 2) {
                        close_window(add_feed_window);
                }

        } else if (w == warning_window && buttons) {
                if (i == 1)
                        close_window(warning_window);

        } else if (w == choices_window && buttons) {
                if (i == 6) {
                        mins = atoi(get_icon_string(choices_window, 1));
                        if (mins < 15) {
                                mins = 15;
                                warn("To avoid overloading feed providers, "
                                                "the minimum update interval "
                                                "is 15 minutes.");
                        }
                        interval = mins * 60;
                        choices_save();
                        if (buttons == wimp_CLICK_SELECT)
                                close_window(choices_window);
                } else if (i == 5) {
                        close_window(choices_window);
                } else if (i == 2 || i == 3) {
                        mins = atoi(get_icon_string(choices_window, 1));
                        if ((i == 2 && buttons == wimp_CLICK_SELECT) ||
                            (i == 3 && buttons == wimp_CLICK_ADJUST))
                                mins -= 3;
                        else
                                mins += 3;
                        if (mins < 15)
                                mins = 15;
                        else if (999 < mins)
                                mins = 999;
                        snprintf(minutes, sizeof minutes, "%i", mins);
                        set_icon_string(choices_window, 1, minutes);
                        xwimp_set_caret_position(choices_window, 1,
                                        0, 0, -1, strlen(minutes));
                } else if (i == 7 || i == 8 ||
                                i == 10 || i == 11 ||
                                i == 13 || i == 14) {
                        if (i == 8 || i == 11 || i == 14)
                                i--;
                        wimp_window_state state;
                        wimp_icon_state icon_state;
                        state.w = w;
                        xwimp_get_window_state(&state);
                        icon_state.w = w;
                        icon_state.i = i;
                        xwimp_get_icon_state(&icon_state);
                        open_menu((wimp_menu *) rufl_family_menu,
                                state.visible.x0 + icon_state.icon.extent.x1,
                                state.visible.y1 + icon_state.icon.extent.y1);
                        current_font_menu = i;
                }
        }
}


void set_pointer(const char *name, int x, int y)
{
        os_error *error;
        error = xosspriteop_set_pointer_shape(osspriteop_USER_AREA, sprites,
                        (osspriteop_id) name, 1, x, y, 0, 0);
        if (error) {
                LOG(("xosspriteop_set_pointer_shape: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }
}


void reset_pointer(void)
{
        os_error *error;
        error = xwimpspriteop_set_pointer_shape("ptr_default", 1, 0, 0, 0, 0);
        if (error) {
                LOG(("xwimpspriteop_set_pointer_shape: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }
}


void key_pressed(wimp_key *key)
{
        os_error *error;

        if (key->w == add_feed_window) {
                if (key->c == wimp_KEY_ESCAPE) {
                        mouse_click(key->w, 2, 0, 0, wimp_CLICK_SELECT);
                        return;
                } else if (key->c == wimp_KEY_RETURN) {
                        mouse_click(key->w, 1, 0, 0, wimp_CLICK_SELECT);
                        return;
                }

        } else if (key->w == choices_window) {
                if (key->c == wimp_KEY_ESCAPE) {
                        mouse_click(key->w, 5, 0, 0, wimp_CLICK_SELECT);
                        return;
                } else if (key->c == wimp_KEY_RETURN) {
                        mouse_click(key->w, 6, 0, 0, wimp_CLICK_SELECT);
                        return;
                } else if (key->c == wimp_KEY_DOWN) {
                        mouse_click(key->w, 2, 0, 0, wimp_CLICK_SELECT);
                        return;
                } else if (key->c == wimp_KEY_UP) {
                        mouse_click(key->w, 3, 0, 0, wimp_CLICK_SELECT);
                        return;
                }

        } else if (key->w == warning_window) {
                if (key->c == wimp_KEY_ESCAPE ||
                    key->c == wimp_KEY_RETURN) {
                        close_window(warning_window);
                }
        }

        error = xwimp_process_key(key->c);
        if (error) {
                LOG(("xwimp_process_key: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }
}


void menu_selection(wimp_selection *selection)
{
        char minutes[10];
        wimp_pointer pointer;

        xwimp_get_pointer_info(&pointer);

        if (current_menu == (wimp_menu *) &iconbar_menu) {
                switch (selection->items[0]) {
                case 1:
                        snprintf(minutes, sizeof minutes, "%i", interval / 60);
                        set_icon_string(choices_window, 1, minutes);
                        set_icon_string(choices_window, 8, font_headings);
                        set_icon_string(choices_window, 11, font_summaries);
                        set_icon_string(choices_window, 14, font_links);
                        open_window(choices_window);
                        xwimp_set_caret_position(choices_window, 1,
                                        0, 0, -1, strlen(minutes));
                        break;
                case 2:
                        last_update = os_read_monotonic_time();
                        feed_update();
                        break;
                case 3:
                        quit = true;
                        break;
                }

        } else if (current_menu == (wimp_menu *) &main_menu) {
                switch (selection->items[0]) {
                case 0:
                        set_icon_string(add_feed_window, 0, "http://");
                        open_window(add_feed_window);
                        xwimp_set_caret_position(add_feed_window, 0,
                                        0, 0, -1, 7);
                        break;
                case 1:
                        feed_remove(current_removing);
                        update_main_window();
                        close_window(feed_window);
                        if (!feed_list_save(FEEDS_WRITE))
                                warn(feed_error);
                        break;
                }
        } else if (current_menu == (wimp_menu *) rufl_family_menu) {
                char *font = ((wimp_menu *) rufl_family_menu)->
                        entries[selection->items[0]].data.indirected_text.text;
                if (current_font_menu == 7)
                        strncpy(font_headings, font, sizeof font_headings);
                else if (current_font_menu == 10)
                        strncpy(font_summaries, font, sizeof font_summaries);
                else if (current_font_menu == 13)
                        strncpy(font_links, font, sizeof font_links);
                set_icon_string(choices_window, 8, font_headings);
                set_icon_string(choices_window, 11, font_summaries);
                set_icon_string(choices_window, 14, font_links);
                update_main_window();
                if (feed_count)
                        update_feed_window(current_feed);
        }

        if (pointer.buttons == wimp_CLICK_ADJUST)
                xwimp_create_menu(current_menu, pointer.pos.x, pointer.pos.y);
}


void open_window(wimp_w w)
{
        const os_VDU_VAR_LIST(5) vars = { { os_MODEVAR_XWIND_LIMIT,
                        os_MODEVAR_YWIND_LIMIT, os_MODEVAR_XEIG_FACTOR,
                        os_MODEVAR_YEIG_FACTOR, os_VDUVAR_END_LIST } };
        int vals[4];
        int width, height;
        wimp_window_state state;
        int dx, dy;
        os_error *error;

        error = xos_read_vdu_variables((const os_vdu_var_list *) &vars, vals);
        if (error) {
                LOG(("xos_read_vdu_variables: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
                return;
        }
        width = (vals[0] + 1) << vals[2];
        height = (vals[1] + 1) << vals[3];

        state.w = w;
        error = xwimp_get_window_state(&state);
        if (error) {
                LOG(("xwimp_get_window_state: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
                return;
        }

        dx = (state.visible.x1 - state.visible.x0) / 2;
        dy = (state.visible.y1 - state.visible.y0) / 2;
        state.visible.x0 = width / 2 - dx;
        state.visible.y0 = height / 2 - dy;
        state.visible.x1 = width / 2 + dx;
        state.visible.y1 = height / 2 + dy;
        state.xscroll = 0;
        state.yscroll = 0;
        state.next = wimp_TOP;

        error = xwimp_open_window((wimp_open *) &state);
        if (error) {
                LOG(("xwimp_open_window: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }
}


void close_window(wimp_w w)
{
        os_error *error;

        error = xwimp_close_window(w);
        if (error) {
                LOG(("xwimp_close_window: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }
}


void open_menu(wimp_menu *menu, int x, int y)
{
        os_error *error;

        error = xwimp_create_menu(menu, x, y);
        if (error) {
                LOG(("xwimp_create_menu: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }
        current_menu = menu;
}


void update_main_window(void)
{
        static char *status = 0;
        int y = 0;
        int y1;
        unsigned int i;
        unsigned int j;
        unsigned int new_items;
        rufl_style style;
        struct paragraph *p;

        free_paragraph_list(&main_window_paragraphs);
        free(status);

        status = malloc(feed_count * 40);
        if (!status) {
                LOG(("out of memory"));
                return;
        }

        for (i = 0; i != feed_count; i++) {
                new_items = 0;
                for (j = 0; j != feeds[i].item_count; j++)
                        if (feeds[i].item[j].new_item)
                                new_items++;
                style = new_items ? rufl_WEIGHT_900 : rufl_WEIGHT_400;

                p = add_paragraph(&main_window_paragraphs, 0, y, 700,
                                0xffaa99, 0x000000,
                                font_headings, style, 200,
                                feeds[i].title ? (char *) feeds[i].title :
                                feeds[i].url,
                                click_main_window, i);
                y1 = p->y1;

                switch (feeds[i].status) {
                case FEED_NEW:
                case FEED_FETCHING:
                case FEED_UPDATE:
                        snprintf(status + i * 40, 40, "Fetching");
                        break;
                case FEED_OK:
                        if (new_items)
                                snprintf(status + i * 40, 40,
                                                "%i items (%i new)",
                                                feeds[i].item_count,
                                                new_items);
                        else
                                snprintf(status + i * 40, 40,
                                                "%i items",
                                                feeds[i].item_count);
                        break;
                case FEED_ERROR:
                        snprintf(status + i * 40, 40, "Failed");
                        break;
                }
                p = add_paragraph(&main_window_paragraphs, 700, y, 1000,
                                0xffaa99, 0x000000,
                                font_headings, style, 200,
                                status + i * 40,
                                click_main_window, i);
                y = p->y1 = y1;

                if (feeds[i].error) {
                        p = add_paragraph(&main_window_paragraphs, 0, y, 1000,
                                        0, 0x0000a0,
                                        font_summaries, style, 200,
                                        feeds[i].error,
                                        click_main_window, i);
                        y = p->y1;
                }

                if (feeds[i].description) {
                        p = add_paragraph(&main_window_paragraphs, 0, y, 1000,
                                        0, 0x000000,
                                        font_summaries, rufl_WEIGHT_400, 200,
                                        feeds[i].description,
                                        click_main_window, i);
                        y = p->y1;
                }

                y += MARGIN;
        }

        set_extent(main_window, y);
}


void set_extent(wimp_w w, int y)
{
        os_box extent = { 0, 0, 1000, 0 };
        wimp_window_state state;
        os_error *error;

        extent.y0 = -y;
        error = xwimp_set_extent(w, &extent);
        if (error) {
                LOG(("xwimp_set_extent: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }

        state.w = w;
        error = xwimp_get_window_state(&state);
        if (error) {
                LOG(("xwimp_get_window_state: 0x%x: %s",
                                error->errnum, error->errmess));
                warn(error->errmess);
        }

        if (state.flags & wimp_WINDOW_OPEN) {
                error = xwimp_close_window(w);
                if (error) {
                        LOG(("xwimp_close_window: 0x%x: %s",
                                        error->errnum, error->errmess));
                        warn(error->errmess);
                }

                /*state.visible.y0 = 100;
                state.visible.y1 = 100 + y;*/
                error = xwimp_open_window((wimp_open *) &state);
                if (error) {
                        LOG(("xwimp_open_window: 0x%x: %s",
                                        error->errnum, error->errmess));
                        warn(error->errmess);
                }
        }
}


void click_main_window(unsigned int i)
{
        unsigned int j;

        update_feed_window(i);
        open_window(feed_window);

        for (j = 0; j != feeds[i].item_count; j++)
                feeds[i].item[j].new_item = false;
        update_main_window();
}


void update_feed_window(unsigned int i)
{
        int y = 0;
        int y1;
        unsigned int j;
        struct paragraph *p;
        rufl_style style;

        current_feed = i;

        free_paragraph_list(&feed_window_paragraphs);

        p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                        0xffaa99, 0x000000,
                        font_headings, rufl_WEIGHT_400, 200,
                        feeds[i].title ? (char *) feeds[i].title : feeds[i].url,
                        0, 0);
        y = p->y1;

        if (feeds[i].link) {
                p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                                0, 0xff0000,
                                font_links, rufl_WEIGHT_400, 160,
                                feeds[i].link,
                                click_feed_link, i);
                y = p->y1;
        }
        if (feeds[i].pub_date) {
                p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                                0, 0x0060ee,
                                font_summaries, rufl_WEIGHT_400 | rufl_SLANTED,
                                160,
                                feeds[i].pub_date,
                                0, 0);
                y = p->y1;
        }
        if (feeds[i].description) {
                p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                                0, 0x000000,
                                font_summaries, rufl_WEIGHT_400, 200,
                                feeds[i].description,
                                0, 0);
                y = p->y1;
        }
        if (feeds[i].copyright) {
                p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                                0, 0x666666,
                                font_summaries, rufl_WEIGHT_400 | rufl_SLANTED, 160,
                                feeds[i].copyright,
                                0, 0);
                y = p->y1;
        }

        y += MARGIN;

        for (j = 0; j != feeds[i].item_count; j++) {
                style = feeds[i].item[j].new_item ? rufl_WEIGHT_900 :
                                rufl_WEIGHT_400;

                p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                                0xa0dddd, 0x000000,
                                font_headings, style, 200,
                                feeds[i].item[j].title ?
                                        (char *) feeds[i].item[j].title : "",
                                0, j);
                y1 = y = p->y1;

                if (feeds[i].item[j].pub_date) {
                        p = add_paragraph(&feed_window_paragraphs, 0, y, 420,
                                        0, 0x0060ee,
                                        font_summaries,
                                        rufl_WEIGHT_400 | rufl_SLANTED, 160,
                                        feeds[i].item[j].pub_date,
                                        0, j);
                        if (y1 < p->y1)
                                y1 = p->y1;
                }
                if (feeds[i].item[j].author) {
                        p = add_paragraph(&feed_window_paragraphs, 420, y, 720,
                                        0, 0x666666,
                                        font_summaries,
                                        rufl_WEIGHT_400 | rufl_SLANTED, 160,
                                        feeds[i].item[j].author,
                                        0, j);
                        if (y1 < p->y1)
                                y1 = p->y1;
                }
                if (feeds[i].item[j].category) {
                        p = add_paragraph(&feed_window_paragraphs, 720, y, 1000,
                                        0, 0xee6000,
                                        font_summaries, rufl_WEIGHT_400, 160,
                                        feeds[i].item[j].category,
                                        0, j);
                        if (y1 < p->y1)
                                y1 = p->y1;
                }
                y = y1;

                if (feeds[i].item[j].link) {
                        p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                                        0, 0xff0000,
                                        font_links, rufl_WEIGHT_400, 160,
                                        feeds[i].item[j].link,
                                        click_item_link, j);
                        y = p->y1;
                }

                if (feeds[i].item[j].description) {
                        p = add_paragraph(&feed_window_paragraphs, 0, y, 1000,
                                        0, 0x000000,
                                        font_summaries, rufl_WEIGHT_400, 180,
                                        feeds[i].item[j].description,
                                        0, j);
                        y = p->y1;
                }

                y += MARGIN;
        }

        set_extent(feed_window, y);
}


void click_feed_link(unsigned int i)
{
        os_error *error;
        error = xuri_dispatch(0, feeds[i].link, task, 0, 0, 0);
        if (error) {
                LOG(("xuri_dispatch: 0x%x: %s",
                                error->errnum, error->errmess));
        }
}


void click_item_link(unsigned int j)
{
        os_error *error;
        error = xuri_dispatch(0, feeds[current_feed].item[j].link, task,
                        0, 0, 0);
        if (error) {
                LOG(("xuri_dispatch: 0x%x: %s",
                                error->errnum, error->errmess));
        }
}


struct paragraph *add_paragraph(struct paragraph **paragraph_list,
                int x0, int y0, int x1, int background, int colour,
                const char *font_family, rufl_style font_style,
                unsigned int font_size, const char *text,
                click_callback click, unsigned int click_i)
{
        struct paragraph *p;
        const char *t;
        size_t len = strlen(text);
        unsigned int lines = 0;
        size_t char_offset;
        int actual_x;
        rufl_code code;

        p = malloc(sizeof *p);
        if (!p)
                return 0;

        p->x0 = x0;
        p->y0 = y0;
        p->x1 = x1;
        p->background = background;
        p->colour = colour;
        p->font_family = font_family;
        p->font_style = font_style;
        p->font_size = font_size;
        p->click = click;
        p->click_i = click_i;
        p->lines = 0;
        p->text[0] = text;

        t = text;
        while (len && lines != MAX_LINES) {
                code = rufl_split(font_family, font_style, font_size, t, len,
                                x1 - x0 - MARGIN - MARGIN,
                                &char_offset, &actual_x);
                if (code != rufl_OK) {
                        LOG(("rufl_split: %i", code));
                        break;
                }
                if (char_offset != len) {
                        size_t space;
                        for (space = char_offset; space && t[space] != ' ';
                                        space--)
                                continue;
                        if (space)
                                char_offset = space + 1;
                }
                len -= char_offset;
                t += char_offset;
                p->text[++lines] = t;
        }

        p->y1 = p->y0 + MARGIN + lines * font_size * 0.2 + MARGIN;
        p->lines = lines;

        p->next = *paragraph_list;
        *paragraph_list = p;

        return p;
}


void free_paragraph_list(struct paragraph **paragraph_list)
{
        struct paragraph *p = *paragraph_list;
        struct paragraph *next;

        while (p) {
                next = p->next;
                free(p);
                p = next;
        }

        *paragraph_list = 0;
}


void redraw_window(wimp_draw *redraw, struct paragraph *paragraphs)
{
        int ox = redraw->box.x0 - redraw->xscroll;
        int oy = redraw->box.y1 - redraw->yscroll;
        int clip_x0 = redraw->clip.x0 - ox;
        int clip_y0 = oy - redraw->clip.y1;
        int clip_x1 = redraw->clip.x1 - ox;
        int clip_y1 = oy - redraw->clip.y0;
        struct paragraph *p;
        unsigned int i;
        os_error *error;
        rufl_code code;

        for (p = paragraphs; p; p = p->next) {
                if (p->x1 < clip_x0 || clip_x1 < p->x0 ||
                                p->y1 < clip_y0 || clip_y1 < p->y0)
                        continue;
                if (p->background)
                        fill_rectangle(ox + p->x0, oy - p->y1,
                                        ox + p->x1, oy - p->y0,
                                        p->background);
                for (i = 0; i != p->lines; i++) {
                        error = xcolourtrans_set_font_colours(font_CURRENT,
                                        p->background << 8, p->colour << 8,
                                        14, 0, 0, 0);
                        if (error) {
                                LOG(("xcolourtrans_set_font_colours: 0x%x: %s",
                                                error->errnum, error->errmess));
                                return;
                        }
                        code = rufl_paint(p->font_family, p->font_style,
                                        p->font_size, p->text[i],
                                        p->text[i + 1] - p->text[i],
                                        ox + p->x0 + MARGIN,
                                        oy - p->y0 - MARGIN -
                                                i * p->font_size * 0.2 -
                                                p->font_size * 0.15,
                                        rufl_BLEND_FONT);
                        if (code != rufl_OK) {
                                LOG(("rufl_paint: %i", code));
                                return;
                        }
                }
        }
}


void fill_rectangle(int x0, int y0, int x1, int y1, int colour)
{
        os_error *error;

        error = xcolourtrans_set_gcol(colour << 8, colourtrans_USE_ECFS,
                        os_ACTION_OVERWRITE, 0, 0);
        if (error) {
                LOG(("xcolourtrans_set_gcol: 0x%x: %s",
                                error->errnum, error->errmess));
                return;
        }

        error = xos_plot(os_MOVE_TO, x0, y0);
        if (error) {
                LOG(("xos_plot: 0x%x: %s", error->errnum, error->errmess));
                return;
        }

        error = xos_plot(os_PLOT_RECTANGLE | os_PLOT_TO, x1, y1);
        if (error) {
                LOG(("xos_plot: 0x%x: %s", error->errnum, error->errmess));
                return;
        }
}


void choices_save(void)
{
        FILE *choices;
        char error[200];

        choices = fopen(CHOICES_WRITE, "w");
        if (!choices) {
                LOG(("fopen: %i: %s", errno, strerror(errno)));
                snprintf(error, sizeof error, "Unable to save choices: %s",
                                strerror(errno));
                warn(error);
                return;
        }
        fprintf(choices, "interval: %i\n", interval);
        fprintf(choices, "font_headings: %s\n", font_headings);
        fprintf(choices, "font_summaries: %s\n", font_summaries);
        fprintf(choices, "font_links: %s\n", font_links);
        fclose(choices);
}


void choices_load(void)
{
        FILE *choices;
        char error[200];
        char s[100];

        choices = fopen(CHOICES_READ, "r");
        if (!choices) {
                LOG(("fopen: %i: %s", errno, strerror(errno)));
                if (errno != ENOENT) {
                        snprintf(error, sizeof error,
                                        "Unable to read choices: %s",
                                        strerror(errno));
                        warn(error);
                }
                return;
        }
        while (fgets(s, sizeof s, choices)) {
                sscanf(s, "interval: %i", &interval);
                sscanf(s, "font_headings: %s", font_headings);
                sscanf(s, "font_summaries: %s", font_summaries);
                sscanf(s, "font_links: %s", font_links);
        }
        fclose(choices);
}


/**
 * Display an error and exit.
 */

void die(const char *error)
{
        os_error warn_error;

        warn_error.errnum = 1;
        strncpy(warn_error.errmess, error, sizeof warn_error.errmess - 1);
        warn_error.errmess[sizeof warn_error.errmess - 1] = '\0';
        xwimp_report_error_by_category(&warn_error,
                        wimp_ERROR_BOX_OK_ICON |
                        wimp_ERROR_BOX_GIVEN_CATEGORY |
                        wimp_ERROR_BOX_CATEGORY_ERROR <<
                                        wimp_ERROR_BOX_CATEGORY_SHIFT,
                        "Sargasso", "!sargasso",
                        (osspriteop_area *) 1, 0, 0);
        exit(EXIT_FAILURE);
}


void warn(const char *warning)
{
        os_error error;

        LOG(("%s", warning));

        if (warning_window) {
                set_icon_string(warning_window, 0, warning);
                open_window(warning_window);
                xwimp_set_caret_position(warning_window, wimp_ICON_WINDOW,
                                -100, -100, 1, 0);
                xos_bell();
        } else {
                strncpy(error.errmess, warning, sizeof error.errmess);
                error.errmess[sizeof error.errmess - 1] = 0;
                xwimp_report_error_by_category(&error,
                                wimp_ERROR_BOX_OK_ICON |
                                wimp_ERROR_BOX_GIVEN_CATEGORY |
                                wimp_ERROR_BOX_CATEGORY_ERROR <<
                                                wimp_ERROR_BOX_CATEGORY_SHIFT,
                                "Sargasso", "!sargasso",
                                (osspriteop_area *) 1, 0, 0);
        }
}


char *get_icon_string(wimp_w w, wimp_i i)
{
        wimp_icon_state icon_state = {w, i};
        os_error *error;

        error = xwimp_get_icon_state(&icon_state);
        if (error) {
                LOG(("xwimp_get_icon_state: 0x%x: %s",
                                error->errnum, error->errmess));
                return "";
        }

        return icon_state.icon.data.indirected_text.text;
}


void set_icon_string(wimp_w w, wimp_i i, const char *text)
{
        wimp_icon_state icon_state = {w, i};
        unsigned int size;
        os_error *error;

        error = xwimp_get_icon_state(&icon_state);
        if (error) {
                LOG(("xwimp_get_icon_state: 0x%x: %s",
                                error->errnum, error->errmess));
                return;
        }
        size = (unsigned int) icon_state.icon.data.indirected_text.size;

        if (!strncmp(icon_state.icon.data.indirected_text.text, text, size))
                return;

        strncpy(icon_state.icon.data.indirected_text.text, text, size);
        icon_state.icon.data.indirected_text.text[size - 1] = '\0';

        xwimp_set_icon_state(w, i, 0, 0);
}