/**
 * Copyright (c) 2015, Timothy Stack
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 * * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * * Neither the name of Timothy Stack nor the names of its contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ''AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"

#include "base/injector.hh"
#include "base/math_util.hh"
#include "lnav.hh"
#include "bookmarks.hh"
#include "sql_util.hh"
#include "environ_vtab.hh"
#include "plain_text_source.hh"
#include "pretty_printer.hh"
#include "sysclip.hh"
#include "log_data_helper.hh"
#include "command_executor.hh"
#include "termios_guard.hh"
#include "readline_highlighters.hh"
#include "field_overlay_source.hh"
#include "hotkeys.hh"
#include "base/opt_util.hh"
#include "shlex.hh"
#include "lnav_util.hh"
#include "lnav_config.hh"
#include "bound_tags.hh"
#include "xterm_mouse.hh"

using namespace std;

class logline_helper {

public:
    logline_helper(logfile_sub_source &lss) : lh_sub_source(lss) {

    };

    logline &move_to_msg_start() {
        content_line_t cl = this->lh_sub_source.at(this->lh_current_line);
        std::shared_ptr<logfile> lf = this->lh_sub_source.find(cl);
        auto ll = lf->begin() + cl;
        while (!ll->is_message()) {
            --ll;
            --this->lh_current_line;
        }

        return (*lf)[cl];
    };

    logline &current_line() {
        content_line_t cl = this->lh_sub_source.at(this->lh_current_line);
        std::shared_ptr<logfile> lf = this->lh_sub_source.find(cl);

        return (*lf)[cl];
    };

    void annotate() {
        this->lh_string_attrs.clear();
        this->lh_line_values.clear();
        content_line_t cl = this->lh_sub_source.at(this->lh_current_line);
        std::shared_ptr<logfile> lf = this->lh_sub_source.find(cl);
        auto ll = lf->begin() + cl;
        auto format = lf->get_format();
        lf->read_full_message(ll, this->lh_msg_buffer);
        format->annotate(cl,
                         this->lh_msg_buffer,
                         this->lh_string_attrs,
                         this->lh_line_values,
                         false);
    };

    std::string to_string(const struct line_range &lr) {
        const char *start = this->lh_msg_buffer.get_data();

        return string(&start[lr.lr_start], lr.length());
    }

    logfile_sub_source &lh_sub_source;
    vis_line_t lh_current_line;
    shared_buffer_ref lh_msg_buffer;
    string_attrs_t lh_string_attrs;
    vector<logline_value> lh_line_values;
};

static int key_sql_callback(exec_context &ec, sqlite3_stmt *stmt)
{
    if (!sqlite3_stmt_busy(stmt)) {
        return 0;
    }

    int ncols = sqlite3_column_count(stmt);

    auto &vars = ec.ec_local_vars.top();

    for (int lpc = 0; lpc < ncols; lpc++) {
        const char *column_name = sqlite3_column_name(stmt, lpc);

        if (sql_ident_needs_quote(column_name)) {
            continue;
        }
        if (sqlite3_column_type(stmt, lpc) == SQLITE_NULL) {
            continue;
        }

        vars[column_name] = string((const char *) sqlite3_column_text(stmt, lpc));
    }

    return 0;
}

bool handle_keyseq(const char *keyseq)
{
    key_map &km = lnav_config.lc_active_keymap;

    const auto &iter = km.km_seq_to_cmd.find(keyseq);
    if (iter == km.km_seq_to_cmd.end()) {
        return false;
    }

    vector<logline_value> values;
    exec_context ec(&values, key_sql_callback, pipe_callback);
    auto &var_stack = ec.ec_local_vars;

    ec.ec_global_vars = lnav_data.ld_exec_context.ec_global_vars;
    var_stack.push(map<string, string>());
    auto &vars = var_stack.top();
    vars["keyseq"] = keyseq;
    const auto &kc = iter->second;

    log_debug("executing key sequence %s: %s", keyseq, kc.kc_cmd.c_str());
    auto result = execute_any(ec, kc.kc_cmd);
    lnav_data.ld_rl_view->set_value(
        result.map(ok_prefix).orElse(err_to_ok).unwrap());

    if (!kc.kc_alt_msg.empty()) {
        shlex lexer(kc.kc_alt_msg);
        string expanded_msg;

        if (lexer.eval(expanded_msg, {
            &vars,
            &ec.ec_global_vars,
        })) {
            lnav_data.ld_rl_view->set_alt_value(expanded_msg);
        }
    }

    return true;
}

bool handle_paging_key(int ch)
{
    if (lnav_data.ld_view_stack.empty()) {
        return false;
    }

    textview_curses *tc = *lnav_data.ld_view_stack.top();
    exec_context &ec = lnav_data.ld_exec_context;
    logfile_sub_source *lss = nullptr;
    text_sub_source *tc_tss = tc->get_sub_source();
    bookmarks<vis_line_t>::type &     bm  = tc->get_bookmarks();

    char keyseq[16];

    snprintf(keyseq, sizeof(keyseq), "x%02x", ch);

    if (handle_keyseq(keyseq)) {
        return true;
    }

    if (tc->handle_key(ch)) {
        return true;
    }

    lss = dynamic_cast<logfile_sub_source *>(tc->get_sub_source());

    /* process the command keystroke */
    switch (ch) {
        case 0x7f:
        case KEY_BACKSPACE:
            break;

        case 'a':
            if (lnav_data.ld_last_view == nullptr) {
                alerter::singleton().chime();
            }
            else {
                textview_curses *tc = lnav_data.ld_last_view;

                lnav_data.ld_last_view = nullptr;
                ensure_view(tc);
            }
            break;

        case 'A':
            if (lnav_data.ld_last_view == nullptr) {
                alerter::singleton().chime();
            }
            else {
                textview_curses *tc = lnav_data.ld_last_view;
                textview_curses *top_tc = *lnav_data.ld_view_stack.top();
                auto *dst_view = dynamic_cast<text_time_translator *>(tc->get_sub_source());
                auto *src_view = dynamic_cast<text_time_translator *>(top_tc->get_sub_source());

                lnav_data.ld_last_view = nullptr;
                if (src_view != nullptr && dst_view != nullptr) {
                    struct timeval top_time = src_view->time_for_row(top_tc->get_top());

                    tc->set_top(vis_line_t(dst_view->row_for_time(top_time)));
                }
                ensure_view(tc);
            }
            break;

        case KEY_F(2):
            if (xterm_mouse::is_available()) {
                auto& mouse_i = injector::get<xterm_mouse&>();
                mouse_i.set_enabled(!mouse_i.is_enabled());
                lnav_data.ld_rl_view->set_value(
                    ok_prefix("info: mouse mode -- ") +
                    (mouse_i.is_enabled() ?
                     ANSI_BOLD("enabled") : ANSI_BOLD("disabled")));
            }
            else {
                lnav_data.ld_rl_view->set_value(
                        "error: mouse support is not available, make sure your TERM is set to "
                                "xterm or xterm-256color");
            }
            break;

        case 'C':
            if (lss) {
                lss->text_clear_marks(&textview_curses::BM_USER);
            }

            lnav_data.ld_select_start.erase(tc);
            lnav_data.ld_last_user_mark.erase(tc);
            tc->get_bookmarks()[&textview_curses::BM_USER].clear();
            tc->reload_data();

            lnav_data.ld_rl_view->set_value(ok_prefix("Cleared bookmarks"));
            break;

        case '>':
        {
            std::pair<int, int> range;

            tc->horiz_shift(tc->get_top(),
                            tc->get_bottom(),
                            tc->get_left(),
                            range);
            if (range.second != INT_MAX) {
                tc->set_left(range.second);
                lnav_data.ld_rl_view->set_alt_value(
                        HELP_MSG_1(m, "to bookmark a line"));
            }
            else{
                alerter::singleton().chime();
            }
        }
            break;

        case '<':
            if (tc->get_left() == 0) {
                alerter::singleton().chime();
            }
            else {
                std::pair<int, int> range;

                tc->horiz_shift(tc->get_top(),
                                tc->get_bottom(),
                                tc->get_left(),
                                range);
                if (range.first != -1) {
                    tc->set_left(range.first);
                }
                else{
                    tc->set_left(0);
                }
                lnav_data.ld_rl_view->set_alt_value(
                        HELP_MSG_1(m, "to bookmark a line"));
            }
            break;

        case 'f':
            if (tc == &lnav_data.ld_views[LNV_LOG]) {
                tc->set_top(bm[&logfile_sub_source::BM_FILES].next(tc->get_top()));
            }
            else if (tc == &lnav_data.ld_views[LNV_TEXT]) {
                textfile_sub_source &tss = lnav_data.ld_text_source;

                if (!tss.empty()) {
                    tss.rotate_left();
                }
            }
            break;

        case 'F':
            if (tc == &lnav_data.ld_views[LNV_LOG]) {
                tc->set_top(bm[&logfile_sub_source::BM_FILES].prev(tc->get_top()));
            }
            else if (tc == &lnav_data.ld_views[LNV_TEXT]) {
                textfile_sub_source &tss = lnav_data.ld_text_source;

                if (!tss.empty()) {
                    tss.rotate_right();
                }
            }
            break;

        case 'z':
            if ((lnav_data.ld_zoom_level - 1) < 0) {
                alerter::singleton().chime();
            }
            else {
                execute_command(ec, "zoom-to " + string(lnav_zoom_strings[lnav_data.ld_zoom_level - 1]));
            }
            break;

        case 'Z':
            if ((lnav_data.ld_zoom_level + 1) >= ZOOM_COUNT) {
                alerter::singleton().chime();
            }
            else {
                execute_command(ec, "zoom-to " + string(lnav_zoom_strings[lnav_data.ld_zoom_level + 1]));
            }
            break;

        case 'J':
            if (lnav_data.ld_last_user_mark.find(tc) ==
                lnav_data.ld_last_user_mark.end() ||
                !tc->is_line_visible(vis_line_t(lnav_data.ld_last_user_mark[tc]))) {
                lnav_data.ld_select_start[tc] = tc->get_top();
                lnav_data.ld_last_user_mark[tc] = tc->get_top();
            }
            else {
                vis_line_t    height;
                unsigned long width;

                tc->get_dimensions(height, width);
                if (lnav_data.ld_last_user_mark[tc] > (tc->get_bottom() - 2) &&
                    tc->get_top() + height < tc->get_inner_height()) {
                    tc->shift_top(1_vl);
                }
                if (lnav_data.ld_last_user_mark[tc] + 1 >=
                    tc->get_inner_height()) {
                    break;
                }
                lnav_data.ld_last_user_mark[tc] += 1;
            }
            tc->toggle_user_mark(&textview_curses::BM_USER,
                                 vis_line_t(lnav_data.ld_last_user_mark[tc]));
            tc->reload_data();

            lnav_data.ld_rl_view->set_alt_value(HELP_MSG_1(
                    c,
                    "to copy marked lines to the clipboard"));
            break;

        case 'K':
        {
            int new_mark;

            if (lnav_data.ld_last_user_mark.find(tc) ==
                lnav_data.ld_last_user_mark.end() ||
                !tc->is_line_visible(vis_line_t(lnav_data.ld_last_user_mark[tc]))) {
                new_mark = tc->get_top();
            }
            else {
                new_mark = lnav_data.ld_last_user_mark[tc];
            }

            tc->toggle_user_mark(&textview_curses::BM_USER,
                                 vis_line_t(new_mark));
            if (new_mark == tc->get_top()) {
                tc->shift_top(-1_vl);
            }
            if (new_mark > 0) {
                lnav_data.ld_last_user_mark[tc] = new_mark - 1;
            }
            else {
                lnav_data.ld_last_user_mark[tc] = new_mark;
                alerter::singleton().chime();
            }
            lnav_data.ld_select_start[tc] = tc->get_top();
            tc->reload_data();

            lnav_data.ld_rl_view->set_alt_value(HELP_MSG_1(
                    c,
                    "to copy marked lines to the clipboard"));
        }
            break;

        case 'M':
            if (lnav_data.ld_last_user_mark.find(tc) ==
                lnav_data.ld_last_user_mark.end()) {
                alerter::singleton().chime();
            }
            else {
                int start_line = min((int)tc->get_top(),
                                     lnav_data.ld_last_user_mark[tc] + 1);
                int end_line = max((int)tc->get_top(),
                                   lnav_data.ld_last_user_mark[tc] - 1);

                tc->toggle_user_mark(&textview_curses::BM_USER,
                                     vis_line_t(start_line),
                                     vis_line_t(end_line));
                tc->reload_data();
            }
            break;

#if 0
    case 'S':
        {
            bookmark_vector<vis_line_t>::iterator iter;

            for (iter = bm[&textview_curses::BM_SEARCH].begin();
                 iter != bm[&textview_curses::BM_SEARCH].end();
                 ++iter) {
                tc->toggle_user_mark(&textview_curses::BM_USER, *iter);
            }

            lnav_data.ld_last_user_mark[tc] = -1;
            tc->reload_data();
        }
        break;
#endif

        case 's':
            if (lss) {
                vis_line_t next_top = vis_line_t(tc->get_top() + 2);

                if (!lss->is_time_offset_enabled()) {
                    lnav_data.ld_rl_view->set_alt_value(
                            HELP_MSG_1(T, "to disable elapsed-time mode"));
                }
                lss->set_time_offset(true);
                while (next_top < tc->get_inner_height()) {
                    if (!lss->find_line(lss->at(next_top))->is_message()) {
                    }
                    else if (lss->get_line_accel_direction(next_top) ==
                             log_accel::A_DECEL) {
                        --next_top;
                        tc->set_top(next_top);
                        break;
                    }

                    ++next_top;
                }
            }
            break;

        case 'S':
            if (lss) {
                vis_line_t next_top = tc->get_top();

                if (!lss->is_time_offset_enabled()) {
                    lnav_data.ld_rl_view->set_alt_value(
                            HELP_MSG_1(T, "to disable elapsed-time mode"));
                }
                lss->set_time_offset(true);
                while (0 <= next_top && next_top < tc->get_inner_height()) {
                    if (!lss->find_line(lss->at(next_top))->is_message()) {
                    }
                    else if (lss->get_line_accel_direction(next_top) ==
                             log_accel::A_DECEL) {
                        --next_top;
                        tc->set_top(next_top);
                        break;
                    }

                    --next_top;
                }
            }
            break;

        case '9':
            if (lss) {
                double tenth = ((double)tc->get_inner_height()) / 10.0;

                tc->shift_top(vis_line_t(tenth));
            }
            break;

        case '(':
            if (lss) {
                double tenth = ((double)tc->get_inner_height()) / 10.0;

                tc->shift_top(vis_line_t(-tenth));
            }
            break;

        case '0':
            if (lss) {
                struct timeval first_time = lss->time_for_row(tc->get_top());
                int        step       = 24 * 60 * 60;
                vis_line_t line       =
                        lss->find_from_time(roundup_size(first_time.tv_sec, step));

                tc->set_top(line);
            }
            break;

        case ')':
            if (lss) {
                struct timeval first_time = lss->time_for_row(tc->get_top());
                time_t     day  = rounddown(first_time.tv_sec, 24 * 60 * 60);
                vis_line_t line = lss->find_from_time(day);

                --line;
                tc->set_top(line);
            }
            break;

        case 'D':
            if (tc->get_top() == 0) {
                alerter::singleton().chime();
            }
            else if (lss) {
                struct timeval first_time = lss->time_for_row(tc->get_top());
                int        step     = ch == 'D' ? (24 * 60 * 60) : (60 * 60);
                time_t     top_time = first_time.tv_sec;
                vis_line_t line     = lss->find_from_time(top_time - step);

                if (line != 0) {
                    --line;
                }
                tc->set_top(line);

                lnav_data.ld_rl_view->set_alt_value(HELP_MSG_1(/, "to search"));
            }
            break;

        case 'd':
            if (lss) {
                struct timeval first_time = lss->time_for_row(tc->get_top());
                int        step = ch == 'd' ? (24 * 60 * 60) : (60 * 60);
                vis_line_t line =
                        lss->find_from_time(first_time.tv_sec + step);

                tc->set_top(line);

                lnav_data.ld_rl_view->set_alt_value(HELP_MSG_1(/, "to search"));
            }
            break;

        case 'o':
        case 'O':
            if (lss) {
                logline_helper start_helper(*lss);

                start_helper.lh_current_line = tc->get_top();
                logline &start_line = start_helper.move_to_msg_start();
                start_helper.annotate();

                struct line_range opid_range = find_string_attr_range(
                        start_helper.lh_string_attrs, &logline::L_OPID);
                if (!opid_range.is_valid()) {
                    alerter::singleton().chime();
                    lnav_data.ld_rl_view->set_value(
                        err_prefix("Log message does not contain an opid"));
                } else {
                    unsigned int opid_hash = start_line.get_opid();
                    logline_helper next_helper(*lss);
                    bool found = false;

                    next_helper.lh_current_line = start_helper.lh_current_line;

                    while (true) {
                        if (ch == 'o') {
                            if (++next_helper.lh_current_line >= tc->get_inner_height()) {
                                break;
                            }
                        }
                        else {
                            if (--next_helper.lh_current_line <= 0) {
                                break;
                            }
                        }
                        logline &next_line = next_helper.current_line();
                        if (!next_line.is_message()) {
                            continue;
                        }
                        if (next_line.get_opid() != opid_hash) {
                            continue;
                        }
                        next_helper.annotate();
                        struct line_range opid_next_range = find_string_attr_range(
                                next_helper.lh_string_attrs, &logline::L_OPID);
                        const char *start_opid = start_helper.lh_msg_buffer.get_data_at(opid_range.lr_start);
                        const char *next_opid = next_helper.lh_msg_buffer.get_data_at(opid_next_range.lr_start);
                        if (opid_range.length() != opid_next_range.length() ||
                            memcmp(start_opid, next_opid, opid_range.length()) != 0) {
                            continue;
                        }
                        found = true;
                        break;
                    }
                    if (found) {
                        lnav_data.ld_rl_view->set_value("");
                        tc->set_top(next_helper.lh_current_line);
                    }
                    else {
                        string opid_str = start_helper.to_string(opid_range);

                        lnav_data.ld_rl_view->set_value(
                            err_prefix("No more messages found with opid: " + opid_str));
                        alerter::singleton().chime();
                    }
                }
            }
            break;

        case 'p':
            if (tc == &lnav_data.ld_views[LNV_LOG]) {
                field_overlay_source *fos;

                fos = (field_overlay_source *) tc->get_overlay_source();
                fos->fos_contexts.top().c_show = !fos->fos_contexts.top().c_show;
                tc->reload_data();
            }
            else if (tc == &lnav_data.ld_views[LNV_DB]) {
                db_overlay_source *dos = (db_overlay_source *) tc->get_overlay_source();

                dos->dos_active = !dos->dos_active;
                tc->reload_data();
            }
            break;

        case 't':
            if (lnav_data.ld_text_source.current_file() == nullptr) {
                alerter::singleton().chime();
                lnav_data.ld_rl_view->set_value(
                    err_prefix("No text files loaded"));
            }
            else if (toggle_view(&lnav_data.ld_views[LNV_TEXT])) {
                lnav_data.ld_rl_view->set_alt_value(HELP_MSG_2(
                        f, F,
                        "to switch to the next/previous file"));
            }
            break;

        case 'T':
            lnav_data.ld_log_source.toggle_time_offset();
            if (lss && lss->is_time_offset_enabled()) {
                lnav_data.ld_rl_view->set_alt_value(
                        HELP_MSG_2(s, S, "to move forward/backward through slow downs"));
            }
            tc->reload_data();
            break;

        case 'I':
        {
            auto &hs = lnav_data.ld_hist_source2;
            auto &hist_tc = lnav_data.ld_views[LNV_HISTOGRAM];

            if (toggle_view(&hist_tc)) {
                auto *src_view = dynamic_cast<text_time_translator *>(tc->get_sub_source());

                if (src_view != nullptr) {
                    struct timeval log_top = src_view->time_for_row(tc->get_top());

                    hist_tc.set_top(vis_line_t(hs.row_for_time(log_top)));
                }
            }
            else {
                lnav_data.ld_view_stack.top() | [&](auto top_tc) {
                    auto *dst_view = dynamic_cast<text_time_translator *>(top_tc->get_sub_source());

                    if (dst_view != nullptr) {
                        struct timeval hist_top_time = hs.time_for_row(hist_tc.get_top());
                        struct timeval curr_top_time = dst_view->time_for_row(top_tc->get_top());
                        if (hs.row_for_time(hist_top_time) != hs.row_for_time(curr_top_time)) {
                            vis_line_t new_top = vis_line_t(dst_view->row_for_time(hist_top_time));
                            top_tc->set_top(new_top);
                            top_tc->set_needs_update();
                        }
                    }
                };
            }
        }
            break;

        case 'V':
        {
            textview_curses *db_tc = &lnav_data.ld_views[LNV_DB];
            db_label_source &dls   = lnav_data.ld_db_row_source;

            if (toggle_view(db_tc)) {
                long log_line_index = dls.column_name_to_index("log_line");

                if (log_line_index == -1) {
                    log_line_index = dls.column_name_to_index("min(log_line)");
                }

                if (log_line_index != -1) {
                    char         linestr[64];
                    int          line_number = (int)tc->get_top();
                    unsigned int row;

                    snprintf(linestr, sizeof(linestr), "%d", line_number);
                    for (row = 0; row < dls.dls_rows.size(); row++) {
                        if (strcmp(dls.dls_rows[row][log_line_index],
                                   linestr) == 0) {
                            vis_line_t db_line(row);

                            db_tc->set_top(db_line);
                            db_tc->set_needs_update();
                            break;
                        }
                    }
                }
            }
            else if (db_tc->get_inner_height() > 0) {
                int db_row = db_tc->get_top();
                tc = &lnav_data.ld_views[LNV_LOG];
                long log_line_index = dls.column_name_to_index("log_line");

                if (log_line_index == -1) {
                    log_line_index = dls.column_name_to_index("min(log_line)");
                }

                if (log_line_index != -1) {
                    unsigned int line_number;

                    if (sscanf(dls.dls_rows[db_row][log_line_index],
                               "%d",
                               &line_number) &&
                        line_number < tc->listview_rows(*tc)) {
                        tc->set_top(vis_line_t(line_number));
                        tc->set_needs_update();
                    }
                }
                else {
                    for (size_t lpc = 0; lpc < dls.dls_headers.size(); lpc++) {
                        date_time_scanner dts;
                        struct timeval tv;
                        struct exttm tm;
                        const char *col_value = dls.dls_rows[db_row][lpc];
                        size_t col_len = strlen(col_value);

                        if (dts.scan(col_value, col_len, nullptr, &tm, tv) != nullptr) {
                            vis_line_t vl;

                            vl = lnav_data.ld_log_source.find_from_time(tv);
                            tc->set_top(vl);
                            tc->set_needs_update();
                            break;
                        }
                    }
                }
            }
        }
            break;

        case '\t':
        case KEY_BTAB:
            if (tc == &lnav_data.ld_views[LNV_DB])
            {
                auto &chart = lnav_data.ld_db_row_source.dls_chart;
                const auto &state = chart.show_next_ident(
                    ch == '\t' ?
                    stacked_bar_chart_base::direction::forward :
                    stacked_bar_chart_base::direction::backward);

                state.match(
                    [&] (stacked_bar_chart_base::show_none) {
                        lnav_data.ld_rl_view->set_value("Graphing no values");
                    },
                    [&] (stacked_bar_chart_base::show_all) {
                        lnav_data.ld_rl_view->set_value("Graphing all values");
                    },
                    [&] (stacked_bar_chart_base::show_one) {
                        string colname;

                        chart.get_ident_to_show(colname);
                        lnav_data.ld_rl_view->set_value(
                            "Graphing column " ANSI_BOLD_START +
                            colname + ANSI_NORM);
                    }
                );

                tc->reload_data();
            } else if (tc_tss != nullptr && tc_tss->tss_supports_filtering) {
                lnav_data.ld_mode = lnav_data.ld_last_config_mode;
                lnav_data.ld_filter_view.reload_data();
                lnav_data.ld_files_view.reload_data();
                if (tc->get_inner_height() > 0_vl) {
                    string_attrs_t::const_iterator line_attr;
                    std::vector<attr_line_t> rows(1);

                    tc->get_data_source()->
                        listview_value_for_rows(*tc, tc->get_top(), rows);
                    string_attrs_t &sa = rows[0].get_attrs();
                    line_attr = find_string_attr(sa, &logline::L_FILE);
                    if (line_attr != sa.end()) {
                        const auto &fc = lnav_data.ld_active_files;
                        auto lf = ((logfile *)line_attr->sa_value.sav_ptr)->
                            shared_from_this();
                        auto iter = find(fc.fc_files.begin(),
                                         fc.fc_files.end(),
                                         lf);
                        if (iter != fc.fc_files.end()) {
                            auto index = distance(fc.fc_files.begin(), iter);
                            auto index_vl = vis_line_t(index);

                            lnav_data.ld_files_view.set_top(index_vl);
                            lnav_data.ld_files_view.set_selection(index_vl);
                        }
                    }
                }
            } else {
                alerter::singleton().chime();
            }
            break;

        case 'x':
            if (tc->toggle_hide_fields()) {
                lnav_data.ld_rl_view->set_value("Showing hidden fields");
            } else {
                lnav_data.ld_rl_view->set_value("Hiding hidden fields");
            }
            tc->set_needs_update();
            break;

        case 'r':
        case 'R':
            if (lss) {
                auto& last_time =
                    injector::get<const relative_time&, last_relative_time_tag>();

                if (last_time.empty()) {
                    lnav_data.ld_rl_view->set_value(
                            "Use the 'goto' command to set the relative time to move by");
                }
                else {
                    vis_line_t vl = tc->get_top(), new_vl;
                    relative_time rt = last_time;
                    content_line_t cl;
                    struct exttm tm;
                    bool done = false;

                    if (ch == 'r') {
                        if (rt.is_negative()) {
                            rt.negate();
                        }
                    } else if (ch == 'R') {
                        if (!rt.is_negative()) {
                            rt.negate();
                        }
                    }

                    cl = lnav_data.ld_log_source.at(vl);
                    logline *ll = lnav_data.ld_log_source.find_line(cl);
                    ll->to_exttm(tm);
                    do {
                        tm = rt.adjust(tm);
                        new_vl = lnav_data.ld_log_source.find_from_time(tm);

                        if (new_vl == 0_vl || new_vl != vl || !rt.is_relative()) {
                            vl = new_vl;
                            done = true;
                        }
                    } while (!done);
                    tc->set_top(vl);
                    lnav_data.ld_rl_view->set_value(" " + rt.to_string());
                }
            }
            break;

        case KEY_CTRL_W:
            execute_command(ec, lnav_data.ld_views[LNV_LOG].get_word_wrap() ?
                            "disable-word-wrap" : "enable-word-wrap");
            break;

        case KEY_CTRL_P:
            lnav_data.ld_preview_hidden = !lnav_data.ld_preview_hidden;
            break;

        default:
            return false;
    }
    return true;
}