! Copyright (c) 2021 Approximatrix, LLC <support@approximatrix.com>
!
! Permission is hereby granted, free of charge, to any person obtaining a copy
! of this software and associated documentation files (the "Software"), to deal
! in the Software without restriction, including without limitation the rights
! to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
! copies of the Software, and to permit persons to whom the Software is
! furnished to do so, subject to the following conditions:
!
! The above copyright notice and this permission notice shall be included in
! all copies or substantial portions of the Software.
!
! The Software shall be used for Good, not Evil.
!
! THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
! IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
! FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
! AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
! LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
! OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
! SOFTWARE.

module request_utils
implicit none

    interface player_link
        module procedure player_link_from_name
        module procedure player_link_from_id
    end interface

    interface instruction_link
        module procedure instruction_link_from_name
        module procedure instruction_link_from_id
    end interface
    
    interface get_player_status_utf8
        module procedure get_player_status_utf8_by_id
        module procedure get_player_status_utf8_by_name
    end interface

contains

    pure function success_code(req)
    use http_codes, only: HTTP_SUCCESS => HTTP_CODE_SUCCESS
    use gemini_codes, only: GEMINI_SUCCESS => GEMINI_CODE_SUCCESS
    use server_response, only: request
    implicit none
    
        class(request), intent(in)::req
        integer::success_code
    
        if(req%protocol == 'gemini') then
            success_code = GEMINI_SUCCESS
        else
            success_code = HTTP_SUCCESS
        end if
        
    end function success_code

    pure function notfound_code(req)
    use http_codes, only: HTTP_FAIL => HTTP_CODE_NOTFOUND
    use gemini_codes, only: GEMINI_FAIL => GEMINI_CODE_PERMFAIL
    use server_response, only: request
    implicit none
    
        class(request), intent(in)::req
        integer::notfound_code
    
        if(req%protocol == 'gemini') then
            notfound_code = GEMINI_FAIL
        else
            notfound_code = HTTP_FAIL
        end if
        
    end function notfound_code
    
    pure function notpermitted_code(req)
    use http_codes, only: HTTP_UNAUTHORIZED => HTTP_CODE_UNAUTHORIZED
    use gemini_codes, only: GEMINI_UNAUTHORIZED => GEMINI_CODE_BAD_REQUEST
    use server_response, only: request
    implicit none
    
        class(request), intent(in)::req
        integer::notpermitted_code
    
        if(req%protocol == 'gemini') then
            ! You might think we'd use Gemini certificates, but fuck certificates...
            ! Just fail with a bad request.
            notpermitted_code = GEMINI_UNAUTHORIZED
        else
            notpermitted_code = HTTP_UNAUTHORIZED 
        end if
        
    end function notpermitted_code

    subroutine basic_mimetype(actual_filename, mimetype) 
    use utilities, only: get_one_line_output_shell_command
    implicit none
    
        character(*), intent(in)::actual_filename
        character(*), intent(out)::mimetype
        
        logical::exists
        
        ! Check for gemini first since it's fake...
        if(index(actual_filename, ".gmi") /= 0) then
            mimetype = "text/gemini"
            
        else
        
            inquire(file=actual_filename, exist=exists)
            if(exists) then
            
                call get_one_line_output_shell_command("mimetype -b "//trim(actual_filename), mimetype)
            
            else
            
                ! If it doesn't exist, use the extension dumbly
                if(index(actual_filename, ".txt") /= 0) then
                    mimetype = "text/plain"
                    
                else if(index(actual_filename, ".json") /= 0) then
                    mimetype = "text/plain"
                
                else if(index(actual_filename, ".html") /= 0) then
                    mimetype = "text/html"
                
                else if(index(actual_filename, ".css") /= 0) then
                    mimetype = "text/css"
                    
                ! Just a catch-all, whatever...
                else
                    mimetype = "application/octet-stream"
                    
                end if
            
            end if
        
        end if
    
    end subroutine basic_mimetype

    pure function get_status_utf8(status) result(res)
    use captain_db
    implicit none
    
        integer, intent(in)::status
        character(4)::res
        
        select case(status)
        
            case(JOB_STATUS_SUCCESS)
                ! Check mark 0x2714
                res = char(226)//char(156)//char(148)//" "
                
            case(JOB_STATUS_FAILURE)
                ! Ballot x 0x2717
                res = char(226)//char(156)//char(151)//" "
                
            case(JOB_STATUS_WORKING)
                ! Runner 0x1f3c3
                res = char(240)//char(159)//char(143)//char(131)
            
            case(PLAYER_STATUS_IDLE)
                ! Sleeping 0x1f4a4
                res = char(240)//char(159)//char(146)//char(164)
                
            case(JOB_STATUS_PENDING)
                ! Envelope 0x2709
                res = char(226)//char(156)//char(137)//" "
                
            case(PLAYER_STATUS_OFFLINE)
                ! Fancy question mark 0xe29d93
                res = char(226)//char(157)//char(147)//" "
                
        end select
        
    end function get_status_utf8

    function get_player_status_utf8_by_id(player_id) result(res)
    use captain_db, only: is_player_online, is_player_busy, &
        PLAYER_STATUS_BUSY, PLAYER_STATUS_IDLE, PLAYER_STATUS_OFFLINE
    implicit none
    
        integer, intent(in)::player_id
        character(4)::res
    
        if(is_player_online(player_id)) then
            if(is_player_busy(player_id)) then
                res = get_status_utf8(PLAYER_STATUS_BUSY)
            else
                res = get_status_utf8(PLAYER_STATUS_IDLE)
            end if
        else
            res = get_status_utf8(PLAYER_STATUS_OFFLINE)
        end if
        
    end function get_player_status_utf8_by_id
    
    function get_player_status_utf8_by_name(player) result(res)
    use captain_db, only: get_player_id
    implicit none
    
        character(*), intent(in)::player
        character(4)::res
    
        res = get_player_status_utf8_by_id(get_player_id(player))
        
    end function get_player_status_utf8_by_name

    function is_request_static(req)
    use server_response
    use logging
    implicit none
    
        class(request), intent(in)::req
        logical::is_request_static
        character(64)::first, last
        
        character(4)::ext
        integer::j
        
        call req%path_component(1, first)
        call req%last_component(last)
        
        j = index(last, ".", back=.true.)
        if(j > 0) then
            ext = last(j+1:len_trim(last))
        else
            ext = " "
        end if
        
        call write_log("Static check: "//trim(first), LOG_DEBUG)
        
        is_request_static = ((trim(first) == "releases") .or. &
                             (trim(first) == "uploads") .or. &
                             (trim(first) == "results") .or. &
                             (trim(first) == "static") .or. &
                             (trim(first) == "favicon.txt") .or. &
                             (trim(first) == "instructions" .and. trim(ext) == "json"))
        
    end function is_request_static

    function request_static(req) result(resp)
    use logging
    use config
    use utilities
    use server_response
    use special_filenames
    implicit none
    
        class(request), intent(in)::req
        type(response)::resp
        character(64)::category
        character(256)::filename
        logical::exists
    
        resp%temporary_file = .false.
        
        call req%path_component(1, category)
        call req%path_starting_with_component(2, filename)
        
        if((req%auth_level < global_permissions%get("view-raw-instructions") .and. trim(category) == "instructions") .or. &
           (req%auth_level < global_permissions%get("access-releases") .and. trim(category) == "releases")  .or. &
           (req%auth_level < global_permissions%get("access-logs") .and. trim(category) == "results")) &
        then
            
            resp%code = notpermitted_code(req)
        
        else
        
            resp%body_filename => get_special_full_filename(trim(category), trim(filename))
    
            inquire(file=resp%body_filename, exist=exists)
            if(.not. exists) then
            
                resp%code = notfound_code(req)
                call write_log("File did not exist: "//resp%body_filename, LOG_NORMAL)
                
            else
                
                resp%code = success_code(req)
                call basic_mimetype(resp%body_filename, resp%body_mimetype)

            end if
            
        end if
    
    end function request_static
    
    function build_link(link, label, gemini_mode, session_token) result(res)
    use server_response, only: gemini_session_link_url
    implicit none
        
        character(*), intent(in)::link, label
        logical,  intent(in)::gemini_mode
        
        ! Passed in to prepend a session identifier in gemini
        character(len=:), pointer, intent(in), optional::session_token
        character(len=:), pointer::res
        character(len=:), pointer::gemlink
        integer::nl
        
        if(gemini_mode) then
        
            if(present(session_token)) then
                gemlink => gemini_session_link_url(link, session_token)
            else
                gemlink => gemini_session_link_url(link, null())
            end if
        
            nl = len_trim(gemlink) + len_trim(label) + len('=>  ')

            allocate(character(len=nl)::res)
            res = '=> '//trim(gemlink)//' '//trim(label)
            
        else
        
            nl = len_trim(link) + len_trim(label) + len('<a href=""></a>')
            allocate(character(len=nl)::res)
            res = '<a href="'//trim(link)//'">'//trim(label)//'</a>'
        
        end if
    
    end function build_link
    
    function element_link_from_name(n, category, gemini_mode, prefix) result(res)
    implicit none
    
        character(*), intent(in)::n, category
        logical, intent(in)::gemini_mode
        character(*), intent(in), optional::prefix
        character(len=:), pointer::res
        
        character(256)::dest
        
        if(present(prefix)) then
            dest = prefix
            if(dest(len_trim(dest):len_trim(dest)) /= '/') then
                dest = trim(dest)//"/"
            end if
        else 
            dest = "/"
        end if
        
        dest = trim(dest)//trim(category)//"/"//trim(n)
        
        if(gemini_mode) then
            dest = trim(dest)//".gmi"
        else
            dest = trim(dest)//".html"
        end if
        
        res => build_link(trim(dest), trim(n), gemini_mode)
    
    end function element_link_from_name
    
    function player_link_from_name(n, gemini_mode, prefix) result(res)
    implicit none
    
        character(*), intent(in)::n
        logical, intent(in)::gemini_mode
        character(*), intent(in), optional::prefix
        
        character(64)::internal_prefix
        character(len=:), pointer::res
        
        if(present(prefix)) then
            internal_prefix = prefix
        else
            internal_prefix = "/"
        end if
        
        res => element_link_from_name(n, "players", gemini_mode, internal_prefix)
    
    end function player_link_from_name
    
    function player_link_from_id(id, gemini_mode, prefix) result(res)
    use captain_db, only: PLAYER_NAME_LENGTH, get_player_name
    implicit none
    
        integer, intent(in)::id
        logical, intent(in)::gemini_mode
        character(*), intent(in), optional::prefix
        character(len=:), pointer::res
        
        character(64)::internal_prefix
        character(PLAYER_NAME_LENGTH)::name
        
         if(present(prefix)) then
            internal_prefix = prefix
        else
            internal_prefix = "/"
        end if
        
        name = " "
        call get_player_name(id, name)
        res => player_link_from_name(name, gemini_mode, internal_prefix)
        
    end function player_link_from_id
    
    function instruction_link_from_name(n, gemini_mode, prefix) result(res)
    implicit none
    
        character(*), intent(in)::n
        logical, intent(in)::gemini_mode
        character(*), intent(in), optional::prefix
        
        character(64)::internal_prefix
        character(len=:), pointer::res
        
        if(present(prefix)) then
            internal_prefix = prefix
        else
            internal_prefix = "/"
        end if
        
        res => element_link_from_name(n, "instructions", gemini_mode, internal_prefix)
    
    end function instruction_link_from_name
    
    function instruction_link_from_id(id, gemini_mode, prefix) result(res)
    use captain_db, only: PLAYER_NAME_LENGTH, get_instruction_name
    implicit none
    
        integer, intent(in)::id
        logical, intent(in)::gemini_mode
        character(*), intent(in), optional::prefix
        character(len=:), pointer::res
        
        character(64)::internal_prefix
        character(PLAYER_NAME_LENGTH)::name
        
         if(present(prefix)) then
            internal_prefix = prefix
        else
            internal_prefix = "/"
        end if
        
        name = " "
        call get_instruction_name(id, name)
        res => instruction_link_from_name(name, gemini_mode, internal_prefix)
        
    end function instruction_link_from_id
        
    function generate_simple_pager(startindex, stopindex, step, maxcount, page, gemini_mode) result(res)
    use logging
    implicit none
    
        integer, intent(in)::startindex, stopindex, step, maxcount
        character(*), intent(in)::page
        logical, intent(in)::gemini_mode
        character(len=:), pointer::res
        
        integer::i
        character(len=:), allocatable::back_page, forward_page
        character(len=:), pointer::back_link, forward_link
        character(5)::num
        integer::res_size
        
        res_size = 128
        
        back_link => null()
        forward_link => null()
        
        if(startindex > 1) then
            i = max(startindex-step, 1)
            allocate(character(len=(len_trim(page)+6)) :: back_page)
            write(num, '(I5)') i
            num = adjustl(num)
            back_page = trim(page)//"?"//trim(num)
            back_link => build_link(back_page, "Newer", gemini_mode)
            deallocate(back_page)
        end if
        
        if(stopindex < maxcount) then
            i = stopindex+1
            allocate(character(len=(len_trim(page)+6)) :: forward_page)
            write(num, '(I5)') i
            num = adjustl(num)
            forward_page = trim(page)//"?"//trim(num)
            forward_link => build_link(forward_page, "Older", gemini_mode)
            deallocate(forward_page)
        end if
    
        if(.not. associated(back_link) .and. .not. associated(forward_link)) then
        
            res => null()
            
        else
        
            if(gemini_mode) then
                res_size = 1
            else
                res_size = len('<p class="pager"> - </p>')
            end if
            
            if(associated(back_link)) then
                res_size = res_size + len(back_link)
            end if
            if(associated(forward_link)) then
                res_size = res_size + len(forward_link)
            end if
            
            allocate(character(len=res_size) :: res)
            res = " "
             
            if(gemini_mode) then
                
                if(associated(back_link)) then
                    res = back_link
                    deallocate(back_link)
                end if
                
                if(associated(forward_link)) then
                    if(len_trim(res) > 0) then
                        res = trim(res)//new_line(' ')//forward_link
                    else
                        res = forward_link
                    end if
                    deallocate(forward_link)
                end if
                
            else
            
                if(associated(back_link)) then
                    res = '<p class="pager">'//back_link
                    deallocate(back_link)
                end if
                
                if(associated(forward_link)) then
                    if(len_trim(res) > 0) then
                        res = trim(res)//" - "//forward_link
                    else
                        res = '<p class="pager">'//forward_link
                    end if
                    deallocate(forward_link)
                end if
                
                res = trim(res)//"</p>"
            
            end if
            
        end if
    
    end function generate_simple_pager
    
    function render_jobs_links(jobs, startindex, stopindex, gemini_mode, link_prefix, session_token) result(res)
    use captain_db
    implicit none
    
        type(job), dimension(:), pointer, intent(in)::jobs
        integer, intent(in), optional::startindex, stopindex
        logical, intent(in)::gemini_mode
        character(*), intent(in), optional::link_prefix
        character(len=:), intent(in), pointer, optional::session_token
        character(len=:), pointer::res
    
        integer::nsize, i, first, last
        character(len=16)::int_text
        character(len=(2*PLAYER_NAME_LENGTH + 64))::link
        
        character(len=:), pointer::link_pointer
        character(len=:), pointer::internal_session_token
        
        character(PLAYER_NAME_LENGTH)::player, instruction
        character(1)::nl = new_line(' ')
        character(64)::int_link_prefix
        
        if(present(link_prefix)) then
            int_link_prefix = link_prefix
        else
            int_link_prefix = " "
        end if
        
        if(present(session_token)) then
            internal_session_token => session_token
        else
            internal_session_token => null()
        end if
        
        if(.not. associated(jobs)) then
            allocate(character(len=32)::res)
            res = "None Yet"
        
        else 
            first = 1
            if(present(startindex)) then
                first = startindex
            end if
            
            last = size(jobs)
            if(present(stopindex)) then
                last = min(size(jobs), stopindex)
            end if
            
            if(first <= last .and. first <= size(jobs)) then
                nsize = (last-first+1)*(2*PLAYER_NAME_LENGTH + 64) + 32
                allocate(character(len=nsize) :: res)
                
                if(gemini_mode) then
                    res = " "
                else
                    res ='<ul class="joblist">'
                end if
                
                do i = first, last
                    call get_instruction_name(jobs(i)%instruction, instruction)
                    call get_player_name(jobs(i)%player, player)
                
                    write(int_text, '(I8)') jobs(i)%id
                    
                    if(gemini_mode) then
                    
                        link_pointer => build_link(trim(int_link_prefix)//"jobs/"//trim(adjustl(int_text))//".gmi", &
                                                   trim(get_status_utf8(jobs(i)%status))//" Job "// &
                                                     trim(adjustl(int_text))//" - "//trim(instruction), &
                                                   .true., internal_session_token)
                               
                        res = trim(res)//nl//nl//link_pointer
                        deallocate(link_pointer)
                        
                    else
                    
                        res = trim(res)//nl//'    <li><div class="job_result_listitem'
                        
                        select case(jobs(i)%status)
                            case(JOB_STATUS_SUCCESS)
                                res = trim(res)//' success">'
                            case(JOB_STATUS_FAILURE)
                                res = trim(res)//' failure">'
                            case(JOB_STATUS_WORKING)
                                res = trim(res)//' working">'
                            case(JOB_STATUS_PENDING)
                                res = trim(res)//' working">'
                            case default
                                res = trim(res)//'">'
                        end select
                        
                        link_pointer => build_link(trim(int_link_prefix)//'jobs/'//trim(adjustl(int_text))//'.html', &
                                                   trim(get_status_utf8(jobs(i)%status))//" Job "// &
                                                     trim(adjustl(int_text))//" - "//trim(instruction), &
                                                   .false., internal_session_token)
                               
                        res = trim(res)//nl//"<p><strong>"//link_pointer//'</strong></p>'//nl//"<p><em>"
                        deallocate(link_pointer)
                    endif
                    
                    select case(jobs(i)%status)
                        case(JOB_STATUS_SUCCESS, JOB_STATUS_FAILURE)
                            res = trim(res)//nl//"Completed on"
                        case(JOB_STATUS_PENDING)
                            res = trim(res)//nl//"Waiting to run on"
                        case(JOB_STATUS_WORKING)
                            res = trim(res)//nl//"Running on"
                    end select
                    
                    res = trim(res)//" "//trim(player)// &
                          " - Last Update: "//trim(jobs(i)%time)
                          
                    if(.not. gemini_mode) then
                        res = trim(res)//"</em></p>"//nl//"    </div></li>"
                    end if 
                    
                end do
            
                if(.not. gemini_mode) then
                    res = trim(res)//nl//"</ul>"
                end if
            
            else
                
                ! Indices exceed array
                allocate(character(len=64)::res)
                write(int_text, '(I8)') first
                res = "None at index "//trim(adjustl(int_text))//" or beyond"
            
            end if
        end if
        
    end function render_jobs_links

    subroutine get_job_page_title(req, title)
    use captain_db
    use server_response
    implicit none
    
        type(request), intent(in)::req
        character(*), intent(out)::title
        
        integer::job_id, i
        character(32)::job_text
        character(PLAYER_NAME_LENGTH)::instruction_name
        
        ! All this to get the job id
        call req%last_component(job_text)
        i = index(job_text, ".")
        job_text(i:len(job_text)) = " "
        read(job_text, '(I8)') job_id

        ! Request instruction name
        i = get_job_instruction(job_id)
        call get_instruction_name(i, instruction_name)
        
        title = "Job "//trim(job_text)//" - "//trim(instruction_name)
        
    end subroutine get_job_page_title

    subroutine handle_instruction_command(req)
    use captain_db
    use server_response
    use remote_launch
    use config, only: global_permissions
    implicit none
    
        type(request), intent(in)::req
        character(32)::command
        character(PLAYER_NAME_LENGTH)::argument, instruction_name
        
        integer::i, j
        
        i = index(req%page, ".", back=.true.)
        
        instruction_name = req%page(1:i-1)
        
        i = index(req%query_string, "=")
        command = req%query_string(1:i-1)
        argument = req%query_string(i+1:len_trim(req%query_string))
        
        if(trim(command) == "launch" .and. req%auth_level >= global_permissions%get("launch-job")) then
            call launch_instructions_on_player(instruction_name, argument)
            
        else if(trim(command) == "assign" .and. req%auth_level >= global_permissions%get("assign-instructions")) then
            i = get_instruction_id(trim(instruction_name))
            j = get_player_id(trim(argument))
            call add_player_for_instruction(i, j)
            
        else if(trim(command) == "remove" .and. req%auth_level >= global_permissions%get("assign-instructions")) then
            i = get_instruction_id(trim(instruction_name))
            j = get_player_id(trim(argument))
            call remove_player_for_instruction(i, j)
            
        end if
    
    end subroutine handle_instruction_command

end module request_utils