#include "sfall_global_scripts.h"

#include <algorithm>
#include <cstring>
#include <string>
#include <vector>

#include "db.h"
#include "input.h"
#include "platform_compat.h"
#include "scripts.h"
#include "sfall_config.h"

namespace fallout {

struct GlobalScript {
    Program* program = nullptr;
    int procs[SCRIPT_PROC_COUNT] = { 0 };
    int repeat = 0;
    int count = 0;
    int mode = 0;
    bool once = true;
};

struct GlobalScriptsState {
    std::vector<std::string> paths;
    std::vector<GlobalScript> globalScripts;
};

static GlobalScriptsState* state = nullptr;

bool sfall_gl_scr_init()
{
    state = new (std::nothrow) GlobalScriptsState();
    if (state == nullptr) {
        return false;
    }

    char* paths;
    configGetString(&gSfallConfig, SFALL_CONFIG_SCRIPTS_KEY, SFALL_CONFIG_GLOBAL_SCRIPT_PATHS, &paths);

    char* curr = paths;
    while (curr != nullptr && *curr != '\0') {
        char* end = strchr(curr, ',');
        if (end != nullptr) {
            *end = '\0';
        }

        char drive[COMPAT_MAX_DRIVE];
        char dir[COMPAT_MAX_DIR];
        compat_splitpath(curr, drive, dir, nullptr, nullptr);

        char** files;
        int filesLength = fileNameListInit(curr, &files, 0, 0);
        if (filesLength != 0) {
            for (int index = 0; index < filesLength; index++) {
                char path[COMPAT_MAX_PATH];
                compat_makepath(path, drive, dir, files[index], nullptr);

                state->paths.push_back(std::string { path });
            }

            fileNameListFree(&files, 0);
        }

        if (end != nullptr) {
            *end = ',';
            curr = end + 1;
        } else {
            curr = nullptr;
        }
    }

    std::sort(state->paths.begin(), state->paths.end());

    return true;
}

void sfall_gl_scr_reset()
{
    if (state != nullptr) {
        sfall_gl_scr_remove_all();
    }
}

void sfall_gl_scr_exit()
{
    if (state != nullptr) {
        sfall_gl_scr_remove_all();

        delete state;
        state = nullptr;
    }
}

void sfall_gl_scr_exec_start_proc()
{
    for (auto& path : state->paths) {
        Program* program = programCreateByPath(path.c_str());
        if (program != nullptr) {
            GlobalScript scr;
            scr.program = program;

            for (int action = 0; action < SCRIPT_PROC_COUNT; action++) {
                scr.procs[action] = programFindProcedure(program, gScriptProcNames[action]);
            }

            state->globalScripts.push_back(std::move(scr));

            _interpret(program, -1);
        }
    }

    tickersAdd(sfall_gl_scr_process_input);
}

void sfall_gl_scr_remove_all()
{
    tickersRemove(sfall_gl_scr_process_input);

    for (auto& scr : state->globalScripts) {
        programFree(scr.program);
    }

    state->globalScripts.clear();
}

void sfall_gl_scr_exec_map_update_scripts(int action)
{
    for (auto& scr : state->globalScripts) {
        if (scr.mode == 0 || scr.mode == 3) {
            if (scr.procs[action] != -1) {
                _executeProcedure(scr.program, scr.procs[action]);
            }
        }
    }
}

static void sfall_gl_scr_process_simple(int mode1, int mode2)
{
    for (auto& scr : state->globalScripts) {
        if (scr.repeat != 0 && (scr.mode == mode1 || scr.mode == mode2)) {
            scr.count++;
            if (scr.count >= scr.repeat) {
                _executeProcedure(scr.program, scr.procs[SCRIPT_PROC_START]);
                scr.count = 0;
            }
        }
    }
}

void sfall_gl_scr_process_main()
{
    sfall_gl_scr_process_simple(0, 3);
}

void sfall_gl_scr_process_input()
{
    sfall_gl_scr_process_simple(1, 1);
}

void sfall_gl_scr_process_worldmap()
{
    sfall_gl_scr_process_simple(2, 3);
}

static GlobalScript* sfall_gl_scr_map_program_to_scr(Program* program)
{
    auto it = std::find_if(state->globalScripts.begin(),
        state->globalScripts.end(),
        [&program](const GlobalScript& scr) {
            return scr.program == program;
        });
    return it != state->globalScripts.end() ? &(*it) : nullptr;
}

void sfall_gl_scr_set_repeat(Program* program, int frames)
{
    GlobalScript* scr = sfall_gl_scr_map_program_to_scr(program);
    if (scr != nullptr) {
        scr->repeat = frames;
    }
}

void sfall_gl_scr_set_type(Program* program, int type)
{
    if (type < 0 || type > 3) {
        return;
    }

    GlobalScript* scr = sfall_gl_scr_map_program_to_scr(program);
    if (scr != nullptr) {
        scr->mode = type;
    }
}

bool sfall_gl_scr_is_loaded(Program* program)
{
    GlobalScript* scr = sfall_gl_scr_map_program_to_scr(program);
    if (scr != nullptr) {
        if (scr->once) {
            scr->once = false;
            return true;
        }

        return false;
    }

    // Not a global script.
    return true;
}

void sfall_gl_scr_update(int burstSize)
{
    for (auto& scr : state->globalScripts) {
        _interpret(scr.program, burstSize);
    }
}

} // namespace fallout