/**
 * Copyright (c) 2018, 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 "lnav.hh"
#include "lnav_util.hh"
#include "log_actions.hh"

using namespace std;

static string execute_action(log_data_helper &ldh,
                             int value_index,
                             const string &action_name)
{
    std::map<string, log_format::action_def>::const_iterator iter;
    logline_value &lv = ldh.ldh_line_values[value_index];
    shared_ptr<logfile> lf = ldh.ldh_file;
    const auto format = lf->get_format();
    pid_t child_pid;
    string retval;

    iter = format->lf_action_defs.find(action_name);

    const log_format::action_def &action = iter->second;

    auto_pipe in_pipe(STDIN_FILENO);
    auto_pipe out_pipe(STDOUT_FILENO);

    in_pipe.open();
    if (action.ad_capture_output) {
        out_pipe.open();
    }

    child_pid = fork();

    in_pipe.after_fork(child_pid);
    out_pipe.after_fork(child_pid);

    switch (child_pid) {
        case -1:
            retval = "error: unable to fork child process -- " + string(strerror(errno));
            break;
        case 0: {
            const char *args[action.ad_cmdline.size() + 1];
            set<std::string> path_set(format->get_source_path());
            char env_buffer[64];
            int value_line;
            string path;

            dup2(STDOUT_FILENO, STDERR_FILENO);
            setenv("LNAV_ACTION_FILE", lf->get_filename().c_str(), 1);
            snprintf(env_buffer, sizeof(env_buffer),
                     "%ld",
                     (ldh.ldh_line - lf->begin()) + 1);
            setenv("LNAV_ACTION_FILE_LINE", env_buffer, 1);
            snprintf(env_buffer, sizeof(env_buffer), "%d", ldh.ldh_y_offset + 1);
            setenv("LNAV_ACTION_MSG_LINE", env_buffer, 1);
            setenv("LNAV_ACTION_VALUE_NAME", lv.lv_meta.lvm_name.get(), 1);
            value_line = ldh.ldh_y_offset - ldh.get_value_line(lv) + 1;
            snprintf(env_buffer, sizeof(env_buffer), "%d", value_line);
            setenv("LNAV_ACTION_VALUE_LINE", env_buffer, 1);

            for (const auto &path_iter : path_set) {
                if (!path.empty()) {
                    path += ":";
                }
                path += path_iter;
            }
            path += ":" + string(getenv("PATH"));
            setenv("PATH", path.c_str(), 1);
            for (size_t lpc = 0; lpc < action.ad_cmdline.size(); lpc++) {
                args[lpc] = action.ad_cmdline[lpc].c_str();
            }
            args[action.ad_cmdline.size()] = nullptr;
            execvp(args[0], (char *const *) args);
            fprintf(stderr,
                    "error: could not exec process -- %s:%s\n",
                    args[0],
                    strerror(errno));
            _exit(0);
        }
            break;
        default: {
            static int exec_count = 0;

            string value = lv.to_string();

            lnav_data.ld_children.push_back(child_pid);

            if (write(in_pipe.write_end(), value.c_str(), value.size()) == -1) {
                perror("execute_action write");
            }
            in_pipe.close();

            if (out_pipe.read_end() != -1) {
                auto pp = make_shared<piper_proc>(
                    out_pipe.read_end(),
                    false,
                    open_temp_file(ghc::filesystem::temp_directory_path() /
                                   "lnav.action.XXXXXX")
                        .map([](auto pair) {
                            ghc::filesystem::remove(pair.first);

                            return pair;
                        })
                        .expect("Cannot create temporary file for action")
                        .second);
                char desc[128];

                lnav_data.ld_pipers.push_back(pp);
                snprintf(desc,
                         sizeof(desc), "[%d] Output of %s",
                         exec_count++,
                         action.ad_cmdline[0].c_str());
                lnav_data.ld_active_files.fc_file_names[desc]
                    .with_fd(pp->get_fd());
                lnav_data.ld_files_to_front.emplace_back( desc, 0 );
            }

            return "";
        }
            break;
    }

    return retval;
}

bool action_delegate::text_handle_mouse(textview_curses &tc, mouse_event &me)
{
    bool retval = false;

    if (me.me_button != mouse_button_t::BUTTON_LEFT) {
        return false;
    }

    vis_line_t mouse_line = vis_line_t(tc.get_top() + me.me_y);
    int mouse_left = tc.get_left() + me.me_x;

    switch (me.me_state) {
        case mouse_button_state_t::BUTTON_STATE_PRESSED:
            if (mouse_line >= vis_line_t(0) && mouse_line <= tc.get_bottom()) {
                size_t line_end_index = 0;
                int x_offset;

                this->ad_press_line = mouse_line;
                this->ad_log_helper.parse_line(mouse_line, true);

                this->ad_log_helper.get_line_bounds(this->ad_line_index, line_end_index);

                struct line_range lr(this->ad_line_index, line_end_index);

                this->ad_press_value = -1;

                x_offset = this->ad_line_index + mouse_left;
                if (lr.contains(x_offset)) {
                    for (size_t lpc = 0;
                         lpc < this->ad_log_helper.ldh_line_values.size();
                         lpc++) {
                        logline_value &lv = this->ad_log_helper.ldh_line_values[lpc];

                        if (lv.lv_origin.contains(x_offset)) {
                            this->ad_press_value = lpc;
                            break;
                        }
                    }
                }
            }
            break;
        case mouse_button_state_t::BUTTON_STATE_DRAGGED:
            if (mouse_line != this->ad_press_line) {
                this->ad_press_value = -1;
            }
            if (this->ad_press_value != -1) {
                retval = true;
            }
            break;
        case mouse_button_state_t::BUTTON_STATE_RELEASED:
            if (this->ad_press_value != -1 && this->ad_press_line == mouse_line) {
                logline_value &lv = this->ad_log_helper.ldh_line_values[this->ad_press_value];
                int x_offset = this->ad_line_index + mouse_left;

                if (lv.lv_origin.contains(x_offset)) {
                    shared_ptr<logfile> lf = this->ad_log_helper.ldh_file;
                    const vector<string> *actions;

                    actions = lf->get_format()->get_actions(lv);
                    if (actions != nullptr && !actions->empty()) {
                        string rc = execute_action(
                            this->ad_log_helper, this->ad_press_value, actions->at(0));

                        lnav_data.ld_rl_view->set_value(rc);
                    }
                }
                retval = true;
            }
            break;
    }

    return retval;
}
