/*   SHS: Syntactically Homogeneous Shell
 *   Copyright (C) 2019  Aidan Hahn
 *
 *   This program is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

package stdlib

import (
    "os"
    "fmt"
    "gitlab.com/whom/shs/ast"
)

func GenFuncTable() ast.FuncTable {
    var stdlib ast.FuncTable
    stdlib = &map[string]*ast.Function{
        "...": &ast.Function{
            Function: expand,
            Name:      "...",
            TimesCalled:   0,
            Args:          1,
        },

        "append": &ast.Function{
            Function: l_append,
            Name:     "append",
            TimesCalled:     0,
            Args:           -1,
        },

        "exit": &ast.Function{
            Function: exit_shell,
            Name:         "exit",
            TimesCalled:       0,
            Args:              0,
        },

        "eq": &ast.Function{
            Function:         eq,
            Name:           "==",
            TimesCalled:       0,
            Args:              2,
        },

        "ne": &ast.Function{
            Function:         ne,
            Name:           "!=",
            TimesCalled:       0,
            Args:              2,
        },

        "<": &ast.Function{
            Function:         lt,
            Name:            "<",
            TimesCalled:       0,
            Args:              2,
        },

        ">": &ast.Function{
            Function:         gt,
            Name:            ">",
            TimesCalled:       0,
            Args:              2,
        },

        "<=": &ast.Function{
            Function:        lte,
            Name:           "<=",
            TimesCalled:       0,
            Args:              2,
        },

        ">=": &ast.Function{
            Function:        gte,
            Name:           ">=",
            TimesCalled:       0,
            Args:              2,
        },

        "!": &ast.Function{
            Function:        not,
            Name:            "!",
            TimesCalled:       0,
            Args:              1,
        },

        "+": &ast.Function{
            Function:      add,
            Name:        "add",
            TimesCalled:     0,
            Args:           -1,
        },

        "-": &ast.Function{
            Function:      sub,
            Name:        "sub",
            TimesCalled:     0,
            Args:           -1,
        },

        "*": &ast.Function{
            Function:     mult,
            Name:       "mult",
            TimesCalled:     0,
            Args:           -1,
        },

        "/": &ast.Function{
            Function:      div,
            Name:        "div",
            TimesCalled:     0,
            Args:           -1,
        },

        "cd": &ast.Function{
            Function:       cd,
            Name:  "changedir",
            TimesCalled:     0,
            Args:            1,
        },

        "concat": &ast.Function{
            Function:   concat,
            Name:"concatenate",
            TimesCalled:     0,
            Args:           -1,
        },

        "print": &ast.Function{
            Function:print_str,
            Name:      "print",
            TimesCalled:     0,
            Args:            1,
        },

        "l": &ast.Function{
            Function:     call,
            Name:       "call",
            TimesCalled:     0,
            Args:           -1,
        },

        "bg": &ast.Function{
            Function:        bgcall,
            Name: "background call",
            TimesCalled:          0,
            Args:                -1,
        },

        "fg": &ast.Function{
            Function:       fg,
            Name: "foreground",
            TimesCalled:     0,
            Args:            0,
        },

        "$": &ast.Function{
            Function: read_cmd,
            Name:   "read cmd",
            TimesCalled:     0,
            Args:           -1,
        },

        "?": &ast.Function{
            Function:   get_exit,
            Name:"get exit code",
            TimesCalled:       0,
            Args:              0,
        },

        /*
        USE NATIVE KILL COMMAND.
        "kill": &ast.Function{
            Function:       kill,
            Name:     "kill job",
            TimesCalled:       0,
            Args:              1,
        },
        */

        "jobs": &ast.Function{
            Function:       jobs,
            Name:    "list jobs",
            TimesCalled:       0,
            Args:              0,
        },

        "info": &ast.Function{
            Function:    sh_info,
            Name:   "Shell Info",
            TimesCalled:       0,
            Args:              1,
        },
    }

    return stdlib
}

func exit_shell(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
    os.Exit(0)
    return nil // I hope execution doesnt get here
}

func sh_info(in *ast.Token, vt ast.VarTable, ft ast.FuncTable) *ast.Token {
    switch in.Tag {
    case ast.BOOL:
        fmt.Printf("BOOL LITERAL\nValue: %s\n", in.Value())
    case ast.STRING:
        fmt.Printf("STRING LITERAL \nValue: %s\n", in.Value())
    case ast.NUMBER:
        fmt.Printf("NUMBER LITERAL \nValue: %s\n", in.Value())
    case ast.LIST:
        fmt.Printf("LIST \nString Value: %s, AST:\n", in.String())
        ast.PrintSExprsIndividually(in)
    case ast.SYMBOL:
        repr := ast.GetVar(in.Value(), vt)
        if repr != nil {
            fmt.Printf("VARIABLE\nTYPE: %s\nVALUE: %s\n", ast.GetTagAsStr(repr.Tag), repr.Value())
            break
        }

        funct := ast.GetFunction(in.Value(), ft)
        if funct != nil {
            fmt.Printf("FUNCTION\nNAME: %s\nTIMES CALLED: %s\nNUM ARGS: %d\n", funct.Name, funct.TimesCalled, funct.Args)
            break
        }

        fmt.Printf("UNKNOWN SYMBOL\n")
    }

    return nil
}