/* SPDX-License-Identifier: GPL-2.0 */
/*
 * Copyright (C) 2002 Roman Zippel <zippel@linux-m68k.org>
 */
%{

#include <ctype.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdbool.h>

#include <xalloc.h>
#include "lkc.h"
#include "internal.h"
#include "preprocess.h"

#define printd(mask, fmt...) if (cdebug & (mask)) printf(fmt)

#define PRINTD          0x0001
#define DEBUG_PARSE     0x0002

int cdebug = PRINTD;

static void yyerror(const char *err);
static void zconf_error(const char *err, ...);
static bool zconf_endtoken(const char *tokenname,
                           const char *expected_tokenname);

struct menu *current_menu, *current_entry, *current_choice;

%}

%union
{
        char *string;
        struct symbol *symbol;
        struct expr *expr;
        struct menu *menu;
        enum symbol_type type;
        enum variable_flavor flavor;
}

%token <string> T_HELPTEXT
%token <string> T_WORD
%token <string> T_WORD_QUOTE
%token T_BOOL
%token T_CHOICE
%token T_CLOSE_PAREN
%token T_COLON_EQUAL
%token T_COMMENT
%token T_CONFIG
%token T_DEFAULT
%token T_DEF_BOOL
%token T_DEF_TRISTATE
%token T_DEPENDS
%token T_ENDCHOICE
%token T_ENDIF
%token T_ENDMENU
%token T_HELP
%token T_HEX
%token T_IF
%token T_IMPLY
%token T_INT
%token T_MAINMENU
%token T_MENU
%token T_MENUCONFIG
%token T_MODULES
%token T_ON
%token T_OPEN_PAREN
%token T_PLUS_EQUAL
%token T_PROMPT
%token T_RANGE
%token T_SELECT
%token T_SOURCE
%token T_STRING
%token T_TRANSITIONAL
%token T_TRISTATE
%token T_VISIBLE
%token T_EOL
%token <string> T_ASSIGN_VAL

%left T_OR
%left T_AND
%left T_EQUAL T_UNEQUAL
%left T_LESS T_LESS_EQUAL T_GREATER T_GREATER_EQUAL
%nonassoc T_NOT

%type <symbol> nonconst_symbol
%type <symbol> symbol
%type <type> type default
%type <expr> expr
%type <expr> if_expr
%type <string> end
%type <menu> if_entry menu_entry choice_entry
%type <string> assign_val
%type <flavor> assign_op

%destructor {
        fprintf(stderr, "%s:%d: missing end statement for this entry\n",
                $$->filename, $$->lineno);
        if (current_menu == $$)
                menu_end_menu();
} if_entry menu_entry choice_entry

%%
input: mainmenu_stmt stmt_list | stmt_list;

/* mainmenu entry */

mainmenu_stmt: T_MAINMENU T_WORD_QUOTE T_EOL
{
        menu_add_prompt(P_MENU, $2, NULL);
};

stmt_list:
          /* empty */
        | stmt_list assignment_stmt
        | stmt_list choice_stmt
        | stmt_list comment_stmt
        | stmt_list config_stmt
        | stmt_list if_stmt
        | stmt_list menu_stmt
        | stmt_list menuconfig_stmt
        | stmt_list source_stmt
        | stmt_list T_WORD error T_EOL  { zconf_error("unknown statement \"%s\"", $2); }
        | stmt_list error T_EOL         { zconf_error("invalid statement"); }
;

stmt_list_in_choice:
          /* empty */
        | stmt_list_in_choice comment_stmt
        | stmt_list_in_choice config_stmt
        | stmt_list_in_choice if_stmt_in_choice
        | stmt_list_in_choice error T_EOL       { zconf_error("invalid statement"); }
;

/* config/menuconfig entry */

config_entry_start: T_CONFIG nonconst_symbol T_EOL
{
        menu_add_entry($2, M_NORMAL);
        printd(DEBUG_PARSE, "%s:%d:config %s\n", cur_filename, cur_lineno, $2->name);
};

config_stmt: config_entry_start config_option_list
{
        if (current_choice) {
                if (!current_entry->prompt) {
                        fprintf(stderr, "%s:%d: error: choice member must have a prompt\n",
                                current_entry->filename, current_entry->lineno);
                        yynerrs++;
                }

                if (current_entry->sym->type != S_BOOLEAN) {
                        fprintf(stderr, "%s:%d: error: choice member must be bool\n",
                                current_entry->filename, current_entry->lineno);
                        yynerrs++;
                }

                /*
                 * If the same symbol appears twice in a choice block, the list
                 * node would be added twice, leading to a broken linked list.
                 * list_empty() ensures that this symbol has not yet added.
                 */
                if (list_empty(&current_entry->sym->choice_link))
                        list_add_tail(&current_entry->sym->choice_link,
                                      &current_choice->choice_members);
        }

        printd(DEBUG_PARSE, "%s:%d:endconfig\n", cur_filename, cur_lineno);
};

menuconfig_entry_start: T_MENUCONFIG nonconst_symbol T_EOL
{
        menu_add_entry($2, M_MENU);
        printd(DEBUG_PARSE, "%s:%d:menuconfig %s\n", cur_filename, cur_lineno, $2->name);
};

menuconfig_stmt: menuconfig_entry_start config_option_list
{
        if (current_entry->prompt)
                current_entry->prompt->type = P_MENU;
        else
                zconf_error("menuconfig statement without prompt");
        printd(DEBUG_PARSE, "%s:%d:endconfig\n", cur_filename, cur_lineno);
};

config_option_list:
          /* empty */
        | config_option_list config_option
        | config_option_list depends
        | config_option_list help
;

config_option: type prompt_stmt_opt T_EOL
{
        menu_set_type($1);
        printd(DEBUG_PARSE, "%s:%d:type(%u)\n", cur_filename, cur_lineno, $1);
};

config_option: T_PROMPT T_WORD_QUOTE if_expr T_EOL
{
        menu_add_prompt(P_PROMPT, $2, $3);
        printd(DEBUG_PARSE, "%s:%d:prompt\n", cur_filename, cur_lineno);
};

config_option: T_TRANSITIONAL T_EOL
{
        current_entry->sym->flags |= SYMBOL_TRANS;
        printd(DEBUG_PARSE, "%s:%d:transitional\n", cur_filename, cur_lineno);
};

config_option: default expr if_expr T_EOL
{
        menu_add_expr(P_DEFAULT, $2, $3);
        if ($1 != S_UNKNOWN)
                menu_set_type($1);
        printd(DEBUG_PARSE, "%s:%d:default(%u)\n", cur_filename, cur_lineno,
                $1);
};

config_option: T_SELECT nonconst_symbol if_expr T_EOL
{
        menu_add_symbol(P_SELECT, $2, $3);
        printd(DEBUG_PARSE, "%s:%d:select\n", cur_filename, cur_lineno);
};

config_option: T_IMPLY nonconst_symbol if_expr T_EOL
{
        menu_add_symbol(P_IMPLY, $2, $3);
        printd(DEBUG_PARSE, "%s:%d:imply\n", cur_filename, cur_lineno);
};

config_option: T_RANGE symbol symbol if_expr T_EOL
{
        menu_add_expr(P_RANGE, expr_alloc_comp(E_RANGE,$2, $3), $4);
        printd(DEBUG_PARSE, "%s:%d:range\n", cur_filename, cur_lineno);
};

config_option: T_MODULES T_EOL
{
        if (modules_sym)
                zconf_error("symbol '%s' redefines option 'modules' already defined by symbol '%s'",
                            current_entry->sym->name, modules_sym->name);
        modules_sym = current_entry->sym;
};

/* choice entry */

choice: T_CHOICE T_EOL
{
        struct symbol *sym = sym_lookup(NULL, 0);

        menu_add_entry(sym, M_CHOICE);
        menu_set_type(S_BOOLEAN);
        INIT_LIST_HEAD(&current_entry->choice_members);

        printd(DEBUG_PARSE, "%s:%d:choice\n", cur_filename, cur_lineno);
};

choice_entry: choice choice_option_list
{
        if (!current_entry->prompt) {
                fprintf(stderr, "%s:%d: error: choice must have a prompt\n",
                        current_entry->filename, current_entry->lineno);
                yynerrs++;
        }

        $$ = menu_add_menu();

        current_choice = current_entry;
};

choice_end: end
{
        current_choice = NULL;

        if (zconf_endtoken($1, "choice")) {
                menu_end_menu();
                printd(DEBUG_PARSE, "%s:%d:endchoice\n", cur_filename, cur_lineno);
        }
};

choice_stmt: choice_entry stmt_list_in_choice choice_end
;

choice_option_list:
          /* empty */
        | choice_option_list choice_option
        | choice_option_list depends
        | choice_option_list help
;

choice_option: T_PROMPT T_WORD_QUOTE if_expr T_EOL
{
        menu_add_prompt(P_PROMPT, $2, $3);
        printd(DEBUG_PARSE, "%s:%d:prompt\n", cur_filename, cur_lineno);
};

choice_option: T_DEFAULT nonconst_symbol if_expr T_EOL
{
        menu_add_symbol(P_DEFAULT, $2, $3);
        printd(DEBUG_PARSE, "%s:%d:default\n", cur_filename, cur_lineno);
};

type:
          T_BOOL                { $$ = S_BOOLEAN; }
        | T_TRISTATE            { $$ = S_TRISTATE; }
        | T_INT                 { $$ = S_INT; }
        | T_HEX                 { $$ = S_HEX; }
        | T_STRING              { $$ = S_STRING; }

default:
          T_DEFAULT             { $$ = S_UNKNOWN; }
        | T_DEF_BOOL            { $$ = S_BOOLEAN; }
        | T_DEF_TRISTATE        { $$ = S_TRISTATE; }

/* if entry */

if_entry: T_IF expr T_EOL
{
        printd(DEBUG_PARSE, "%s:%d:if\n", cur_filename, cur_lineno);
        menu_add_entry(NULL, M_IF);
        menu_add_dep($2, NULL);
        $$ = menu_add_menu();
};

if_end: end
{
        if (zconf_endtoken($1, "if")) {
                menu_end_menu();
                printd(DEBUG_PARSE, "%s:%d:endif\n", cur_filename, cur_lineno);
        }
};

if_stmt: if_entry stmt_list if_end
;

if_stmt_in_choice: if_entry stmt_list_in_choice if_end
;

/* menu entry */

menu: T_MENU T_WORD_QUOTE T_EOL
{
        menu_add_entry(NULL, M_MENU);
        menu_add_prompt(P_MENU, $2, NULL);
        printd(DEBUG_PARSE, "%s:%d:menu\n", cur_filename, cur_lineno);
};

menu_entry: menu menu_option_list
{
        $$ = menu_add_menu();
};

menu_end: end
{
        if (zconf_endtoken($1, "menu")) {
                menu_end_menu();
                printd(DEBUG_PARSE, "%s:%d:endmenu\n", cur_filename, cur_lineno);
        }
};

menu_stmt: menu_entry stmt_list menu_end
;

menu_option_list:
          /* empty */
        | menu_option_list visible
        | menu_option_list depends
;

source_stmt: T_SOURCE T_WORD_QUOTE T_EOL
{
        printd(DEBUG_PARSE, "%s:%d:source %s\n", cur_filename, cur_lineno, $2);
        zconf_nextfile($2);
        free($2);
};

/* comment entry */

comment: T_COMMENT T_WORD_QUOTE T_EOL
{
        menu_add_entry(NULL, M_COMMENT);
        menu_add_prompt(P_COMMENT, $2, NULL);
        printd(DEBUG_PARSE, "%s:%d:comment\n", cur_filename, cur_lineno);
};

comment_stmt: comment comment_option_list
;

comment_option_list:
          /* empty */
        | comment_option_list depends
;

/* help option */

help_start: T_HELP T_EOL
{
        printd(DEBUG_PARSE, "%s:%d:help\n", cur_filename, cur_lineno);
        zconf_starthelp();
};

help: help_start T_HELPTEXT
{
        if (current_entry->help) {
                free(current_entry->help);
                zconf_error("'%s' defined with more than one help text",
                            current_entry->sym->name ?: "<choice>");
        }

        /* Is the help text empty or all whitespace? */
        if ($2[strspn($2, " \f\n\r\t\v")] == '\0')
                zconf_error("'%s' defined with blank help text",
                            current_entry->sym->name ?: "<choice>");

        current_entry->help = $2;
};

/* depends option */

depends: T_DEPENDS T_ON expr if_expr T_EOL
{
        menu_add_dep($3, $4);
        printd(DEBUG_PARSE, "%s:%d:depends on\n", cur_filename, cur_lineno);
};

/* visibility option */
visible: T_VISIBLE if_expr T_EOL
{
        menu_add_visibility($2);
};

/* prompt statement */

prompt_stmt_opt:
          /* empty */
        | T_WORD_QUOTE if_expr
{
        menu_add_prompt(P_PROMPT, $1, $2);
};

end:      T_ENDMENU T_EOL       { $$ = "menu"; }
        | T_ENDCHOICE T_EOL     { $$ = "choice"; }
        | T_ENDIF T_EOL         { $$ = "if"; }
;

if_expr:  /* empty */                   { $$ = NULL; }
        | T_IF expr                     { $$ = $2; }
;

expr:     symbol                                { $$ = expr_alloc_symbol($1); }
        | symbol T_LESS symbol                  { $$ = expr_alloc_comp(E_LTH, $1, $3); }
        | symbol T_LESS_EQUAL symbol            { $$ = expr_alloc_comp(E_LEQ, $1, $3); }
        | symbol T_GREATER symbol               { $$ = expr_alloc_comp(E_GTH, $1, $3); }
        | symbol T_GREATER_EQUAL symbol         { $$ = expr_alloc_comp(E_GEQ, $1, $3); }
        | symbol T_EQUAL symbol                 { $$ = expr_alloc_comp(E_EQUAL, $1, $3); }
        | symbol T_UNEQUAL symbol               { $$ = expr_alloc_comp(E_UNEQUAL, $1, $3); }
        | T_OPEN_PAREN expr T_CLOSE_PAREN       { $$ = $2; }
        | T_NOT expr                            { $$ = expr_alloc_one(E_NOT, $2); }
        | expr T_OR expr                        { $$ = expr_alloc_two(E_OR, $1, $3); }
        | expr T_AND expr                       { $$ = expr_alloc_two(E_AND, $1, $3); }
;

/* For symbol definitions, selects, etc., where quotes are not accepted */
nonconst_symbol: T_WORD { $$ = sym_lookup($1, 0); free($1); };

symbol:   nonconst_symbol
        | T_WORD_QUOTE  { $$ = sym_lookup($1, SYMBOL_CONST); free($1); }
;

/* assignment statement */

assignment_stmt:  T_WORD assign_op assign_val T_EOL     { variable_add($1, $3, $2); free($1); free($3); }

assign_op:
          T_EQUAL       { $$ = VAR_RECURSIVE; }
        | T_COLON_EQUAL { $$ = VAR_SIMPLE; }
        | T_PLUS_EQUAL  { $$ = VAR_APPEND; }
;

assign_val:
        /* empty */             { $$ = xstrdup(""); };
        | T_ASSIGN_VAL
;

%%

/**
 * transitional_check_sanity - check transitional symbols have no other
 *                             properties
 *
 * @menu: menu of the potentially transitional symbol
 *
 * Return: -1 if an error is found, 0 otherwise.
 */
static int transitional_check_sanity(const struct menu *menu)
{
        struct property *prop;

        if (!menu->sym || !(menu->sym->flags & SYMBOL_TRANS))
                return 0;

        /* Check for depends and visible conditions. */
        if ((menu->dep && !expr_is_yes(menu->dep)) ||
            (menu->visibility && !expr_is_yes(menu->visibility))) {
                fprintf(stderr, "%s:%d: error: %s",
                        menu->filename, menu->lineno,
                        "transitional symbols can only have help sections\n");
                return -1;
        }

        /* Check for any property other than "help". */
        for (prop = menu->sym->prop; prop; prop = prop->next) {
                if (prop->type != P_COMMENT) {
                        fprintf(stderr, "%s:%d: error: %s",
                                prop->filename, prop->lineno,
                                "transitional symbols can only have help sections\n");
                        return -1;
                }
        }

        return 0;
}

/**
 * choice_check_sanity - check sanity of a choice member
 *
 * @menu: menu of the choice member
 *
 * Return: -1 if an error is found, 0 otherwise.
 */
static int choice_check_sanity(const struct menu *menu)
{
        struct property *prop;
        int ret = 0;

        for (prop = menu->sym->prop; prop; prop = prop->next) {
                if (prop->type == P_DEFAULT) {
                        fprintf(stderr, "%s:%d: error: %s",
                                prop->filename, prop->lineno,
                                "defaults for choice values not supported\n");
                        ret = -1;
                }

                if (prop->menu != menu && prop->type == P_PROMPT &&
                    prop->menu->parent != menu->parent) {
                        fprintf(stderr, "%s:%d: error: %s",
                                prop->filename, prop->lineno,
                                "choice value has a prompt outside its choice group\n");
                        ret = -1;
                }
        }

        return ret;
}

void conf_parse(const char *name)
{
        struct menu *menu;

        autoconf_cmd = str_new();

        str_printf(&autoconf_cmd, "\ndeps_config := \\\n");

        zconf_initscan(name);

        _menu_init();

        if (getenv("ZCONF_DEBUG"))
                yydebug = 1;
        yyparse();

        str_printf(&autoconf_cmd,
                   "\n"
                   "$(autoconfig): $(deps_config)\n"
                   "$(deps_config): ;\n");

        env_write_dep(&autoconf_cmd);

        /* Variables are expanded in the parse phase. We can free them here. */
        variable_all_del();

        if (yynerrs)
                exit(1);
        if (!modules_sym)
                modules_sym = &symbol_no;

        if (!menu_has_prompt(&rootmenu)) {
                current_entry = &rootmenu;
                menu_add_prompt(P_MENU, "Main menu", NULL);
        }

        menu_finalize();

        menu_for_each_entry(menu) {
                struct menu *child;

                if (menu->sym && sym_check_deps(menu->sym))
                        yynerrs++;

                if (transitional_check_sanity(menu))
                        yynerrs++;

                if (menu->sym && sym_is_choice(menu->sym)) {
                        menu_for_each_sub_entry(child, menu)
                                if (child->sym && choice_check_sanity(child))
                                        yynerrs++;
                }
        }

        if (yynerrs)
                exit(1);
        conf_set_changed(true);
}

static bool zconf_endtoken(const char *tokenname,
                           const char *expected_tokenname)
{
        if (strcmp(tokenname, expected_tokenname)) {
                zconf_error("unexpected '%s' within %s block",
                            tokenname, expected_tokenname);
                yynerrs++;
                return false;
        }
        if (strcmp(current_menu->filename, cur_filename)) {
                zconf_error("'%s' in different file than '%s'",
                            tokenname, expected_tokenname);
                fprintf(stderr, "%s:%d: location of the '%s'\n",
                        current_menu->filename, current_menu->lineno,
                        expected_tokenname);
                yynerrs++;
                return false;
        }
        return true;
}

static void zconf_error(const char *err, ...)
{
        va_list ap;

        yynerrs++;
        fprintf(stderr, "%s:%d: ", cur_filename, cur_lineno);
        va_start(ap, err);
        vfprintf(stderr, err, ap);
        va_end(ap);
        fprintf(stderr, "\n");
}

static void yyerror(const char *err)
{
        fprintf(stderr, "%s:%d: %s\n", cur_filename, cur_lineno, err);
}

static void print_quoted_string(FILE *out, const char *str)
{
        const char *p;
        int len;

        putc('"', out);
        while ((p = strchr(str, '"'))) {
                len = p - str;
                if (len)
                        fprintf(out, "%.*s", len, str);
                fputs("\\\"", out);
                str = p + 1;
        }
        fputs(str, out);
        putc('"', out);
}

static void print_symbol(FILE *out, const struct menu *menu)
{
        struct symbol *sym = menu->sym;
        struct property *prop;

        if (sym_is_choice(sym))
                fprintf(out, "\nchoice\n");
        else
                fprintf(out, "\nconfig %s\n", sym->name);
        switch (sym->type) {
        case S_BOOLEAN:
                fputs("  bool\n", out);
                break;
        case S_TRISTATE:
                fputs("  tristate\n", out);
                break;
        case S_STRING:
                fputs("  string\n", out);
                break;
        case S_INT:
                fputs("  integer\n", out);
                break;
        case S_HEX:
                fputs("  hex\n", out);
                break;
        default:
                fputs("  ???\n", out);
                break;
        }
        for (prop = sym->prop; prop; prop = prop->next) {
                if (prop->menu != menu)
                        continue;
                switch (prop->type) {
                case P_PROMPT:
                        fputs("  prompt ", out);
                        print_quoted_string(out, prop->text);
                        if (!expr_is_yes(prop->visible.expr)) {
                                fputs(" if ", out);
                                expr_fprint(prop->visible.expr, out);
                        }
                        fputc('\n', out);
                        break;
                case P_DEFAULT:
                        fputs( "  default ", out);
                        expr_fprint(prop->expr, out);
                        if (!expr_is_yes(prop->visible.expr)) {
                                fputs(" if ", out);
                                expr_fprint(prop->visible.expr, out);
                        }
                        fputc('\n', out);
                        break;
                case P_SELECT:
                        fputs( "  select ", out);
                        expr_fprint(prop->expr, out);
                        fputc('\n', out);
                        break;
                case P_IMPLY:
                        fputs( "  imply ", out);
                        expr_fprint(prop->expr, out);
                        fputc('\n', out);
                        break;
                case P_RANGE:
                        fputs( "  range ", out);
                        expr_fprint(prop->expr, out);
                        fputc('\n', out);
                        break;
                case P_MENU:
                        fputs( "  menu ", out);
                        print_quoted_string(out, prop->text);
                        fputc('\n', out);
                        break;
                default:
                        fprintf(out, "  unknown prop %d!\n", prop->type);
                        break;
                }
        }
        if (menu->help) {
                int len = strlen(menu->help);
                while (menu->help[--len] == '\n')
                        menu->help[len] = 0;
                fprintf(out, "  help\n%s\n", menu->help);
        }
}

void zconfdump(FILE *out)
{
        struct property *prop;
        struct symbol *sym;
        struct menu *menu;

        menu = rootmenu.list;
        while (menu) {
                if ((sym = menu->sym))
                        print_symbol(out, menu);
                else if ((prop = menu->prompt)) {
                        switch (prop->type) {
                        case P_COMMENT:
                                fputs("\ncomment ", out);
                                print_quoted_string(out, prop->text);
                                fputs("\n", out);
                                break;
                        case P_MENU:
                                fputs("\nmenu ", out);
                                print_quoted_string(out, prop->text);
                                fputs("\n", out);
                                break;
                        default:
                                ;
                        }
                        if (!expr_is_yes(prop->visible.expr)) {
                                fputs("  depends ", out);
                                expr_fprint(prop->visible.expr, out);
                                fputc('\n', out);
                        }
                }

                if (menu->list)
                        menu = menu->list;
                else if (menu->next)
                        menu = menu->next;
                else while ((menu = menu->parent)) {
                        if (menu->prompt && menu->prompt->type == P_MENU)
                                fputs("\nendmenu\n", out);
                        if (menu->next) {
                                menu = menu->next;
                                break;
                        }
                }
        }
}