'INI Manager v1.01
'Fellippe Heitor, 2017-2021 - fellippe@qb64.org - @fellippeheitor

SUB IniCommit
    SHARED currentIniFileName$, IniWholeFile$, currentIniFileLOF AS _UNSIGNED LONG
    SHARED IniNewFile$, IniDisableAutoCommit, IniCODE

    IF currentIniFileName$ = "" THEN IniCODE = 18: EXIT SUB

    IniWholeFile$ = IniNewFile$
    currentIniFileLOF = LEN(IniNewFile$)

    IF NOT IniDisableAutoCommit THEN
        DIM fileNum AS INTEGER

        fileNum = FREEFILE
        OPEN currentIniFileName$ FOR BINARY AS #fileNum

        IF LEN(IniWholeFile$) < LOF(fileNum) THEN
            CLOSE fileNum
            OPEN currentIniFileName$ FOR OUTPUT AS #fileNum: CLOSE #fileNum
            OPEN currentIniFileName$ FOR BINARY AS #fileNum
        END IF

        PUT #fileNum, 1, IniNewFile$
        CLOSE #fileNum 'flush
    END IF
END SUB

FUNCTION IniGetSection$ (__section$)
    SHARED IniPosition AS _UNSIGNED LONG, IniCODE, currentIniFileName$
    SHARED IniLF$, IniWholeFile$, currentIniFileLOF AS _UNSIGNED LONG

    IF currentIniFileName$ = "" THEN IniCODE = 18: EXIT FUNCTION
    IF currentIniFileLOF = 0 OR LEN(LTRIM$(RTRIM$(IniWholeFile$))) = 0 THEN IniCODE = 17: EXIT FUNCTION

    IniCODE = 0

    DIM section$, foundSection AS _UNSIGNED LONG, endSection AS _UNSIGNED LONG
    DIM i AS _UNSIGNED LONG, Bracket1 AS _UNSIGNED LONG, sectionStart AS _UNSIGNED LONG
    DIM inQuote AS _BYTE

    section$ = IniFormatSection$(__section$)
    IF IniCODE THEN EXIT FUNCTION

    IF section$ = "[]" THEN
        'fetch the "global" section, if present
        sectionStart = INSTR(IniWholeFile$, "[")
        IF sectionStart = 0 THEN IniGetSection$ = IniWholeFile$: EXIT FUNCTION

        FOR i = sectionStart - 1 TO 1 STEP -1
            IF ASC(IniWholeFile$, i) = 10 THEN foundSection = i + 1: EXIT FOR
            IF ASC(IniWholeFile$, i) <> 32 THEN EXIT FOR
        NEXT

        IF i = 0 THEN foundSection = 1

        IniGetSection$ = LEFT$(IniWholeFile$, foundSection - 1)
    ELSE
        DO
            sectionStart = INSTR(sectionStart + 1, LCASE$(IniWholeFile$), LCASE$(section$))
            IF sectionStart = 0 THEN IniCODE = 14: EXIT DO

            'make sure it's a valid section header
            foundSection = 0
            FOR i = sectionStart - 1 TO 1 STEP -1
                IF ASC(IniWholeFile$, i) = 10 THEN foundSection = i + 1: EXIT FOR
                IF ASC(IniWholeFile$, i) <> 32 THEN EXIT FOR
            NEXT

            IF i = 0 THEN foundSection = 1

            IF foundSection > 0 THEN
                'we found it; time to identify where this section ends
                '(either another [section] or the end of the file
                Bracket1 = sectionStart
                checkAgain:
                Bracket1 = INSTR(Bracket1 + 1, IniWholeFile$, "[")

                IF Bracket1 > 0 THEN
                    'found a bracket; check if it's inside quotes
                    inQuote = 0
                    FOR i = 1 TO Bracket1 - 1
                        IF ASC(IniWholeFile$, i) = 34 THEN inQuote = NOT inQuote
                    NEXT
                    IF inQuote THEN GOTO checkAgain

                    FOR i = Bracket1 - 1 TO 1 STEP -1
                        IF ASC(IniWholeFile$, i) = 10 THEN endSection = i + 1 - LEN(IniLF$): EXIT FOR
                        IF ASC(IniWholeFile$, i) = 61 THEN GOTO checkAgain 'bracket is inside a key's value
                        IF i <= foundSection THEN EXIT FOR
                    NEXT
                    IniGetSection$ = MID$(IniWholeFile$, foundSection, endSection - foundSection)
                ELSE
                    IniGetSection$ = MID$(IniWholeFile$, foundSection)
                END IF
                EXIT FUNCTION
            END IF
        LOOP
    END IF
END FUNCTION

FUNCTION IniFormatSection$ (__section$)
    SHARED IniCODE

    DIM section$

    section$ = LTRIM$(RTRIM$(__section$))

    'sections are in the format [section name] - add brackets if not passed
    IF LEFT$(section$, 1) <> "[" THEN section$ = "[" + section$
    IF RIGHT$(section$, 1) <> "]" THEN section$ = section$ + "]"

    IF INSTR(MID$(section$, 2, LEN(section$) - 3), "[") OR INSTR(MID$(section$, 2, LEN(section$) - 3), "]") THEN
        IniCODE = 15
        EXIT FUNCTION
    END IF

    IniFormatSection$ = section$
END FUNCTION

FUNCTION ReadSetting$ (file$, __section$, __key$)
    SHARED IniLastSection$, IniLastKey$, IniWholeFile$, IniLF$
    SHARED IniPosition AS _UNSIGNED LONG, IniSectionData$
    SHARED IniCODE, IniAllowBasicComments
    SHARED currentIniFileLOF AS _UNSIGNED LONG

    IniLoad file$
    IF IniCODE THEN EXIT FUNCTION

    IF currentIniFileLOF = 0 OR LEN(LTRIM$(RTRIM$(IniWholeFile$))) = 0 THEN IniCODE = 17: EXIT FUNCTION

    DIM Equal AS _UNSIGNED LONG, tempValue$, key$, section$
    DIM Quote AS _UNSIGNED LONG, Comment AS _UNSIGNED LONG
    DIM i AS LONG, FoundLF AS _UNSIGNED LONG

    section$ = IniFormatSection(__section$)
    IF IniCODE THEN EXIT FUNCTION

    'fetch the desired section$
    IniSectionData$ = IniGetSection(section$)
    IF IniCODE > 0 AND IniCODE <> 17 THEN EXIT FUNCTION

    IF LEN(IniSectionData$) = 0 AND section$ <> "[]" THEN IniCODE = 14: EXIT FUNCTION

    IniLastSection$ = section$

    IniPosition = 0

    key$ = LTRIM$(RTRIM$(__key$))
    IniLastKey$ = ""
    IF key$ = "" THEN IniCODE = 12: EXIT FUNCTION

    IF LEFT$(key$, 1) = ";" OR LEFT$(key$, 1) = "'" OR INSTR(key$, "[") > 0 OR INSTR(key$, "]") > 0 OR INSTR(key$, "=") > 0 THEN
        IniCODE = 12
        EXIT FUNCTION
    END IF

    IniLastKey$ = key$

    IF IniPosition > 0 THEN Equal = IniPosition: GOTO KeyFound
    CheckKey:
    IniPosition = INSTR(IniPosition + 1, LCASE$(IniSectionData$), LCASE$(key$))

    IF IniPosition > 0 THEN
        'identify if this occurrence is actually a key and not part of a key name/value
        FOR i = IniPosition - 1 TO 1 STEP -1
            IF ASC(IniSectionData$, i) = 10 THEN EXIT FOR
            IF ASC(IniSectionData$, i) <> 10 AND ASC(IniSectionData$, i) <> 32 THEN
                'not a key
                GOTO CheckKey
            END IF
        NEXT

        'check if there's nothing but an equal sign ahead
        FOR i = IniPosition + LEN(key$) TO LEN(IniSectionData$)
            IF ASC(IniSectionData$, i) = ASC("=") THEN EXIT FOR
            IF ASC(IniSectionData$, i) <> ASC("=") AND ASC(IniSectionData$, i) <> 32 THEN
                'not the key
                GOTO CheckKey
            END IF
        NEXT

        'so far so good; check if there is an assignment
        Equal = INSTR(IniPosition, IniSectionData$, "=")
        KeyFound:
        FoundLF = INSTR(IniPosition, IniSectionData$, IniLF$)

        IF FoundLF > 0 THEN
            IF Equal > FoundLF THEN GOTO CheckKey
        ELSE
            FoundLF = LEN(IniSectionData$) + 1
            IF Equal = 0 THEN GOTO CheckKey
        END IF

        tempValue$ = LTRIM$(RTRIM$(MID$(IniSectionData$, Equal + 1, FoundLF - Equal - 1)))

        IF LEN(tempValue$) > 0 THEN
            IF LEFT$(tempValue$, 1) = CHR$(34) THEN
                tempValue$ = MID$(tempValue$, 2)
                Quote = INSTR(tempValue$, CHR$(34))
                IF Quote > 0 THEN
                    tempValue$ = LEFT$(tempValue$, Quote - 1)
                END IF
            ELSE
                IF IniAllowBasicComments THEN Comment = INSTR(tempValue$, "'") 'BASIC style comments accepted
                IF Comment = 0 THEN Comment = INSTR(tempValue$, ";")
                IF Comment > 0 THEN
                    tempValue$ = LTRIM$(RTRIM$(LEFT$(tempValue$, Comment - 1)))
                END IF
            END IF
        ELSE
            IniCODE = 2
        END IF
    ELSE
        IniCODE = 3
        EXIT FUNCTION
    END IF

    ReadSetting$ = tempValue$
    IniLastSection$ = IniCurrentSection$
END FUNCTION

FUNCTION IniCurrentSection$
    SHARED IniPosition AS _UNSIGNED LONG, IniSectionData$, IniWholeFile$

    DIM GlobalPosition AS _UNSIGNED LONG, i AS _UNSIGNED LONG
    DIM ClosingBracket AS _UNSIGNED LONG

    GlobalPosition = INSTR(IniWholeFile$, IniSectionData$) + IniPosition - 1

    CheckSection:
    FOR i = GlobalPosition - 1 TO 1 STEP -1
        IF ASC(IniWholeFile$, i) = ASC("[") THEN
            GlobalPosition = i: EXIT FOR
        END IF
    NEXT

    IF i = 0 THEN IniCurrentSection$ = "[]": EXIT FUNCTION

    'identify if this occurrence is actually a section header and not something else
    FOR i = GlobalPosition - 1 TO 1 STEP -1
        IF ASC(IniWholeFile$, i) = 10 THEN EXIT FOR
        IF ASC(IniWholeFile$, i) <> 10 AND ASC(IniWholeFile$, i) <> 32 THEN
            'not a section header
            GOTO CheckSection
        END IF
    NEXT

    ClosingBracket = INSTR(GlobalPosition, IniWholeFile$, "]")
    IF ClosingBracket > 0 THEN
        IniCurrentSection$ = MID$(IniWholeFile$, GlobalPosition, ClosingBracket - GlobalPosition + 1)
    END IF
END FUNCTION

SUB WriteSetting (file$, __section$, __key$, __value$)
    SHARED IniPosition AS _UNSIGNED LONG, IniCODE, currentIniFileName$
    SHARED IniLF$, IniWholeFile$, IniSectionData$
    SHARED IniLastSection$, IniLastKey$, IniNewFile$
    SHARED IniDisableAddQuotes

    DIM tempValue$, section$, key$, value$

    IniCODE = 0

    'prepare variables for the write operation
    section$ = IniFormatSection$(__section$)
    IF IniCODE THEN EXIT SUB

    key$ = LTRIM$(RTRIM$(__key$))
    IF key$ = "" THEN IniCODE = 12: EXIT SUB
    IniLastKey$ = key$

    value$ = LTRIM$(RTRIM$(__value$))
    IF LTRIM$(STR$(VAL(value$))) <> value$ THEN
        IF NOT IniDisableAddQuotes THEN
            'if not a numeric value and value contains spaces, add quotation marks
            IF INSTR(value$, CHR$(32)) THEN value$ = CHR$(34) + value$ + CHR$(34)
        END IF
    END IF

    'Read the existing key to fill IniPosition
    tempValue$ = ReadSetting$(file$, section$, key$)

    'map IniPosition (set in the section block) to the global file position
    IniPosition = INSTR(IniWholeFile$, IniSectionData$) + IniPosition - 1

    IF IniCODE = 1 OR IniCODE = 17 THEN
        'file not found or empty; create a new one
        IF file$ = "" THEN file$ = currentIniFileName$
        IF file$ = "" THEN IniCODE = 21: EXIT SUB

        currentIniFileName$ = file$

        IF section$ <> "[]" THEN
            IniNewFile$ = section$ + IniLF$
        END IF

        IniNewFile$ = IniNewFile$ + key$ + "=" + value$

        IniCODE = 0
        IniCommit
        IniLoad file$
        IF IniCODE = 0 THEN IniCODE = 11
        IniLastSection$ = section$
        EXIT SUB
    END IF

    IF IniCODE = 0 OR IniCODE = 2 THEN 'key found and read back; write new value$
        IF LCASE$(IniLastSection$) = LCASE$(section$) THEN
            IF LTRIM$(RTRIM$(__value$)) = tempValue$ AND LEN(LTRIM$(RTRIM$(__value$))) > 0 THEN
                'identical values skip the writing routine
                IniCODE = 8
                EXIT SUB
            END IF

            DIM nextLine AS _UNSIGNED LONG
            nextLine = INSTR(IniPosition + 1, IniWholeFile$, IniLF$)

            'create new file contents
            IniNewFile$ = LEFT$(IniWholeFile$, IniPosition - 1)
            IniNewFile$ = IniNewFile$ + key$ + "=" + value$

            IF nextLine > 0 THEN
                IniNewFile$ = IniNewFile$ + MID$(IniWholeFile$, nextLine)
            END IF

            IniCommit

            IniCODE = 4
        END IF
    ELSEIF IniCODE = 3 OR IniCODE = 14 THEN 'Key not found, Section not found
        IniCODE = 0
        IF LCASE$(IniLastSection$) = LCASE$(section$) THEN
            'find this section$ in the current ini file;
            DIM Bracket1 AS _UNSIGNED LONG
            DIM beginSection AS _UNSIGNED LONG, endSection AS _UNSIGNED LONG
            DIM i AS _UNSIGNED LONG

            beginSection = 0
            endSection = 0

            CheckSection:
            beginSection = INSTR(beginSection + 1, LCASE$(IniWholeFile$), LCASE$(section$))
            IF beginSection = 0 THEN GOTO CreateSection

            'identify if this occurrence is actually the section header and not something else
            FOR i = beginSection - 1 TO 1 STEP -1
                IF ASC(IniWholeFile$, i) = 10 THEN EXIT FOR
                IF ASC(IniWholeFile$, i) <> 10 AND ASC(IniWholeFile$, i) <> 32 THEN
                    'not the section header
                    GOTO CheckSection
                END IF
            NEXT

            'we found it; time to identify where this section ends
            '(either another [section], a blank line or the end of the file
            Bracket1 = INSTR(beginSection + 1, IniWholeFile$, "[")
            IF Bracket1 > 0 THEN
                FOR i = Bracket1 - 1 TO 1 STEP -1
                    IF ASC(IniWholeFile$, i) = 10 THEN endSection = i + 1 - LEN(IniLF$): EXIT FOR
                    IF i <= beginSection THEN EXIT FOR
                NEXT
            END IF

            IF endSection > 0 THEN
                'add values to the end of the specified section$
                IniNewFile$ = LEFT$(IniWholeFile$, endSection - 1)
                IniNewFile$ = IniNewFile$ + key$ + "=" + value$ + IniLF$
                IF MID$(IniWholeFile$, endSection, LEN(IniLF$)) <> IniLF$ THEN IniNewFile$ = IniNewFile$ + IniLF$
                IniNewFile$ = IniNewFile$ + MID$(IniWholeFile$, endSection)
            ELSE
                'add values to the end of the file
                IniNewFile$ = IniWholeFile$
                IF RIGHT$(IniNewFile$, LEN(IniLF$)) = IniLF$ THEN
                    IniNewFile$ = IniNewFile$ + key$ + "=" + value$
                ELSE
                    IniNewFile$ = IniNewFile$ + IniLF$ + key$ + "=" + value$
                END IF
            END IF

            IniCommit

            IF IniCODE = 0 THEN IniCODE = 7
            EXIT SUB
        ELSE
            CreateSection:
            IniNewFile$ = IniWholeFile$
            IF section$ = "[]" THEN GOTO WriteAtTop

            IF RIGHT$(IniNewFile$, LEN(IniLF$) * 2) = IniLF$ + IniLF$ THEN
                IniNewFile$ = IniNewFile$ + section$ + IniLF$ + key$ + "=" + value$ + IniLF$
            ELSEIF RIGHT$(IniNewFile$, LEN(IniLF$)) = IniLF$ THEN
                IniNewFile$ = IniNewFile$ + IniLF$ + section$ + IniLF$ + key$ + "=" + value$ + IniLF$
            ELSE
                IniNewFile$ = IniNewFile$ + IniLF$ + IniLF$ + section$ + IniLF$ + key$ + "=" + value$ + IniLF$
            END IF

            IniCommit

            IF IniCODE = 0 THEN IniCODE = 9 ELSE IniCODE = 16
            EXIT SUB
        END IF

        'if not found, key$=value$ is written to the beginning of the file
        WriteAtTop:
        IniNewFile$ = key$ + "=" + value$ + IniLF$
        IF LEFT$(LTRIM$(IniWholeFile$), 1) = "[" THEN IniNewFile$ = IniNewFile$ + IniLF$
        IniNewFile$ = IniNewFile$ + IniWholeFile$

        IniCommit

        IniCODE = 5
    END IF
END SUB

SUB IniSetAddQuotes (state AS _BYTE)
    SHARED IniDisableAddQuotes
    IF state THEN
        IniDisableAddQuotes = 0
    ELSE
        IniDisableAddQuotes = -1
    END IF
END SUB

SUB IniSetForceReload (state AS _BYTE)
    SHARED IniForceReload
    IF state THEN
        IniForceReload = -1
    ELSE
        IniForceReload = 0
    END IF
END SUB

SUB IniSetAllowBasicComments (state AS _BYTE)
    SHARED IniAllowBasicComments
    IF state THEN
        IniAllowBasicComments = -1
    ELSE
        IniAllowBasicComments = 0
    END IF
END SUB

SUB IniSetAutoCommit (state AS _BYTE)
    SHARED IniDisableAutoCommit
    IF state THEN
        IniDisableAutoCommit = 0
    ELSE
        IniDisableAutoCommit = -1
    END IF
END SUB

SUB IniLoad (file$)
    SHARED IniCODE, currentIniFileName$, IniLF$, IniWholeFile$
    SHARED currentIniFileLOF AS _UNSIGNED LONG
    SHARED IniForceReload
    DIM fileNum AS INTEGER

    'Error messages are returned with IniCODE
    IniCODE = 0

    IF file$ <> "" AND currentIniFileName$ <> file$ THEN currentIniFileName$ = ""

    IF IniForceReload AND LEN(currentIniFileName$) > 0 THEN
        file$ = currentIniFileName$
        currentIniFileName$ = ""
    END IF

    'Passing an empty file$ is allowed if user already
    'passed a valid file in this session.
    IF currentIniFileName$ = "" THEN
        'initialization
        IF _FILEEXISTS(file$) THEN
            currentIniFileName$ = file$

            'Load file into memory
            fileNum = FREEFILE
            OPEN currentIniFileName$ FOR BINARY AS #fileNum
            currentIniFileLOF = LOF(fileNum)
            IniWholeFile$ = SPACE$(currentIniFileLOF)
            GET #fileNum, 1, IniWholeFile$
            CLOSE #fileNum
            
            'Check if this ini file uses CRLF or LF
            IF INSTR(IniWholeFile$, CHR$(13)) THEN IniLF$ = CHR$(13) + CHR$(10) ELSE IniLF$ = CHR$(10)
        ELSE
            IniFileNotFound:
            IniCODE = 1

            $IF WIN THEN
                IniLF$ = CHR$(13) + CHR$(10)
            $ELSE
                IniLF$ = CHR$(10)
            $END IF
            EXIT SUB
        END IF
    ELSEIF NOT _FILEEXISTS(currentIniFileName$) THEN
        currentIniFileName$ = ""
        GOTO IniFileNotFound
    END IF
END SUB