! 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 instructions
implicit none

contains

    function parse_instructions(filename) result(j)
    use json_module
    implicit none
    
        type(json_file)::j
        character(*), intent(in)::filename
        
        call j%initialize()
        call j%load_file(filename=filename)
        
    end function parse_instructions
    
    subroutine destroy_instructions(j)
    use json_module
    implicit none
    
        type(json_file)::j
        call j%destroy()
    
    end subroutine destroy_instructions
    
    function work_available(j)
    use json_module
    implicit none
    
        class(json_file)::j
        logical::work_available
        
        character(len=:), allocatable::json_string_value
        logical::found
        
        call j%get("status", json_string_value, found)
        
        if(found) then
            ! GNU Extension... :(
            Print *, fdate()//" Checkin status: "//json_string_value
            work_available = (json_string_value /= "idle")
        else
            work_available = .false.
        end if
        
    end function work_available
    
    subroutine get_instruction_name_from_checkin(j, name)
    use json_module
    implicit none
    
        class(json_file)::j
        character(*), intent(out)::name
        
        character(len=:), allocatable::json_string_value
        logical::found
        
        name = " "
        call j%get("instruction", json_string_value, found)
        if(found) then
            name = json_string_value
        end if
        
    end subroutine get_instruction_name_from_checkin
    
    function get_job_id_from_checkin(j)
    use json_module
    implicit none
    
        class(json_file)::j
        integer::get_job_id_from_checkin
        
        character(len=:), allocatable::json_string_value
        logical::found
        
        get_job_id_from_checkin = -1
        call j%get("job", json_string_value, found)
        if(found) then
            read(json_string_value, *) get_job_id_from_checkin
        end if
        
    end function get_job_id_from_checkin
    
    subroutine get_description(j, description)
    use json_module
    implicit none
    
        class(json_file)::j
        character(*), intent(out)::description
        character(len=:), allocatable::json_string_value
        logical::found
        
        call j%get("description", json_string_value, found)
        if(.not. found .or. .not. allocated(json_string_value)) then
            description = "(instructions)"
        else
            description = json_string_value
        end if
        
    end subroutine get_description
    
    function get_job_id(j) result(id)
    use json_module
    implicit none
    
        class(json_file)::j
        integer::id
        
        logical::found
        
        call j%get("id", id, found)
        if(.not. found) then
            id = -1
        end if

    end function get_job_id
    
    function get_task_count(j) result(n)
    use json_module
    implicit none
    
        class(json_file)::j
        integer::n
        
        type(json_value), pointer ::server
        logical::found
        character(3)::index_string
        n = 0
        
        found = .true.
        do while(found)
            n = n + 1
            write(index_string, '(I3)') n
            call j%get("tasks("//trim(index_string)//")", server, found)
        end do
        n = n - 1
        
    end function get_task_count
    
    pure subroutine task_component(i, component, label)
    implicit none
        
        integer, intent(in)::i
        character(*), intent(in)::component
        character(*), intent(out)::label
        
        write(label, '(A6,I3,A2)') "tasks(", i, ")."
        label = trim(label)//trim(component)
    
    end subroutine task_component
    
    function get_task_string(j, i, component, res) result(found)
    use json_module
    implicit none
        
        class(json_file)::j
        integer, intent(in)::i
        character(*), intent(in)::component
        character(*), intent(out)::res
        logical::found
        
        character(len=64)::label
        character(len=:), allocatable::json_string_value
        
        call task_component(i, component, label)
        
        call j%get(trim(label), json_string_value, found)
        
        if(allocated(json_string_value)) then
            res = json_string_value
        end if
        
    end function get_task_string
    
    function get_task_logical(j, i, component, res) result(found)
    use json_module
    implicit none
        
        class(json_file)::j
        integer, intent(in)::i
        character(*), intent(in)::component
        logical, intent(out)::res
        logical::found
        
        character(len=64)::label
        character(len=:), allocatable::json_string_value
        
        call task_component(i, component, label)
        
        call j%get(trim(label), res, found)

    end function get_task_logical
    
    subroutine get_task_name(j, i, description)
    use json_module
    implicit none
    
        class(json_file)::j
        character(*), intent(out)::description
        integer, intent(in)::i
        logical::found

        found = get_task_string(j, i, "name", description)
        
        if(.not. found) then
            write(description, '(A4, 1X, I3)') "Task", i
        end if
        
    end subroutine get_task_name
    
    function get_task_failure_okay(j, i) result(res)
    use json_module, only: json_file
    implicit none
    
        class(json_file)::j
        integer, intent(in)::i
        
        logical::res
        
        if(.not. get_task_logical(j, i, "failure_okay", res)) then
            res = .false.
        end if
        
    end function get_task_failure_okay
    
    subroutine get_task_operation(j, i, op)
    use json_module
    implicit none
    
        class(json_file)::j
        character(*), intent(out)::op
        integer, intent(in)::i
        logical::found

        found = get_task_string(j, i, "operation", op)
        
        if(.not. found) then
            op = " "
        end if
        
    end subroutine get_task_operation

    function perform_task(j, job_id, i, capture_filename) result(success)
    use json_module
    use tasks
    use utilities
    implicit none
    
        class(json_file)::j
        integer, intent(in)::job_id, i
        character(len=:), pointer, intent(out)::capture_filename
        logical::success
        
        character(32)::operation
        character(256)::url
        character(256)::filename
        character(256)::branch
        character(256)::cmd
        
        logical::destructive
        logical, dimension(4)::found
        
        call get_task_operation(j, i, operation)
        
        Write(*, '(1X, A5, 1X, I3, 2X)', advance='no') "Task:", i
        Print *, "Operation: "//trim(operation)
        
        if(len_trim(operation) == 0) then
            success = .false.
            capture_filename => null()
            return
        end if
        
        found = .true.
        capture_filename => null()
        
        if(trim(operation) == "upload") then
            found(1) = get_task_string(j, i, "url", url)
            found(2) = get_task_string(j, i, "filename", filename)
            if(.not. all(found,1)) then
                success = .false.
            else
                if(index(filename, "*") > 0 .or. index(filename, "?") > 0) then
                    success = upload_glob(url, filename, job_id)
                else
                    success = upload(url, filename, job_id)
                end if
            end if
        
        else if(trim(operation) == "download") then
            found(1) = get_task_string(j, i, "url", url)
            found(2) = get_task_string(j, i, "filename", filename)
            if(.not. all(found,1)) then
                success = .false.
            else
                success = download(url, filename)
            end if
        
        else if(trim(operation) == "git_update") then
            capture_filename => generate_temporary_filename()
        
            found(1) = get_task_string(j, i, "origin", url)
            
            found(2) = get_task_string(j, i, "branch", branch)
            if(.not. found(2)) then
                branch = "master"
                found(2) = .true.
            end if
            
            found(3) = get_task_string(j, i, "directory", filename)
            ! If no directory is specified, do it in the current directory
            if(.not. found(3)) then
                filename = '.'
                found(3) = .true.
            end if
            
            
            found(4) = get_task_logical(j, i, "destructive", destructive)
            if(.not. found(4)) then
                destructive = .false.
                found(4) = .true.
            end if
            
            if(.not. all(found,1)) then
                success = .false.
            else
                success = git_update(url, branch, filename, destructive, capture_filename)
            end if
        
        
        else if(trim(operation) == "shell") then
            capture_filename => generate_temporary_filename()
        
            found(1) = get_task_string(j, i, "command", cmd)
            found(2) = get_task_string(j, i, "directory", filename)
            
            ! If no directory is specified, do it in the current directory
            if(.not. found(2)) then
                filename = '.'
                found(2) = .true.
            end if
            
            if(.not. all(found,1)) then
                success = .false.
            else
                success = shell(cmd, filename, capture_filename)
            end if
        
        else if(trim(operation) == "delete_tree") then
            found(1) = get_task_string(j, i, "directory", filename)
            
            if(.not. all(found,1)) then
                success = .false.
            else
                success = delete_tree(filename)
            end if
        
        end if
        
        if(get_task_failure_okay(j, i) .and. .not. success) then
            Print *, "Reseting to failure"
            success = .true.
        else if(.not. success) then
            Print *, "Task failure"
        end if
        
    end function perform_task
    
    subroutine perform_tasks(j, job_id)
    use json_module
    use talking
    use player_endpoints
    use utilities, only: delete_file
    implicit none
    
        class(json_file)::j
        integer, intent(in)::job_id
        
        integer::task_count
        integer::i
        integer::server_status
        logical::res
        character(len=:), pointer::captured_filename
        character(len=1024)::url
        character(len=40)::operation
        
        task_count = get_task_count(j)
        
        Print *, "Task count: ", task_count
        
        ! Remember to zero-index your json!
        do i = 1, task_count
            call get_task_operation(j, i, operation)
            call get_status_url(job_id, i, url, status=STATUS_STARTING, task_type=operation)
            
            Print *, "Reporting: "//trim(url)
            server_status = request_to_ignored(url)
            
            res = perform_task(j, job_id, i, captured_filename)
        
            if(associated(captured_filename)) then
                if(res) then
                    call get_status_url(job_id, i, url, status=STATUS_COMPLETED)
                    server_status = request_to_ignored(url)
                    
                    call get_status_url(job_id, i, url, posting=.true.)
                    server_status = send_file(url, captured_filename)
                    
                    ! Get rid of the local file
                    call delete_file(captured_filename)
                    deallocate(captured_filename)
                    captured_filename => null()
                else
                    call get_status_url(job_id, i, url, status=STATUS_FAILED)
                    server_status = request_to_ignored(url)
                    
                    call get_status_url(job_id, i, url, posting=.true.)
                    server_status = send_file(url, captured_filename)
                    
                    exit
                endif
                
            else
                if(res) then
                    call get_status_url(job_id, i, url, status=STATUS_COMPLETED)
                    server_status = request_to_ignored(url)
                else
                    call get_status_url(job_id, i, url, status=STATUS_FAILED)
                    server_status = request_to_ignored(url)
                    Print *, "Attempted reporting failure"
                    exit
                endif
            end if
            
        end do
        
        call get_job_report_url(job_id, res, url)
        server_status = request_to_ignored(url)
        
    end subroutine perform_tasks
    
end module instructions