module captain_db
use sqlite
implicit none
    
    integer, parameter::PLAYER_NAME_LENGTH = 128
    integer, parameter::FILENAME_NAME_LENGTH = 1024
    
    integer, parameter::JOB_STATUS_SUCCESS = 1
    integer, parameter::JOB_STATUS_FAILURE = 2
    integer, parameter::JOB_STATUS_WORKING = 3
    
    integer, parameter::PLAYER_STATUS_BUSY = JOB_STATUS_WORKING
    integer, parameter::PLAYER_STATUS_IDLE = 100
    
    character(1024)::database_file
    type(c_ptr)::db
    
    type :: job
    
        integer::id
        integer::instruction
        integer::player
        integer::status
        character(32)::time
        
    end type
    
    interface is_player_busy
        module procedure is_player_busy_by_id
        module procedure is_player_busy_by_name
    end interface is_player_busy
    
contains

    subroutine initialize_db(filename)
    use logging
    implicit none
    
        character(*), intent(in)::filename
        logical::exists
        
        inquire(file=filename, exist=exists)
        if(.not. exists) then
            call write_log("Database does not exist, exiting")
            call shutdown()
            stop
        end if
        
        if(sqlite3_open(filename, db) == SQLITE_OK) then
            database_file = filename
        else
            Print *, "ERROR: Could not open db"
            stop
        end if
        
    end subroutine initialize_db
    
    subroutine shutdown_db()
    implicit none
    
        integer::i
    
        i = sqlite3_close(db)
        
    end subroutine shutdown_db
    
    subroutine add_player_db(name, token)
    implicit none
    
        character(*), intent(in)::name
        character(*), intent(in), optional::token
        type(sqlite3_stmt)::stmt
        
        character(64)::my_token
        
        if(present(token)) then
            my_token = token
        else
            my_token = "None"
        end if

        if(stmt%prepare(db, "INSERT INTO players(name, token) VALUES(?, ?)") == SQLITE_OK) then
            if(stmt%bind_text(1, name) == SQLITE_OK .and. stmt%bind_text(2, my_token) == SQLITE_OK) then
                call stmt%step_now()
            end if
        end if
        call stmt%finalize()
    
    end subroutine add_player_db
    
    subroutine update_player_token_db(name, token)
    implicit none
    
        character(*), intent(in)::name
        character(*), intent(in)::token
        type(sqlite3_stmt)::stmt
        
        if(stmt%prepare(db, "UPDATE players SET token=? WHERE name=?") == SQLITE_OK) then
            if(stmt%bind_text(2, name) == SQLITE_OK .and. stmt%bind_text(1, token) == SQLITE_OK) then
                call stmt%step_now()
            end if
        end if
        call stmt%finalize()
    
    end subroutine update_player_token_db
    
    subroutine remove_player_db(name)
    implicit none
    
        character(*), intent(in)::name
        type(sqlite3_stmt)::stmt
        
        if(stmt%prepare(db, "DELETE FROM players WHERE name=?") == SQLITE_OK) then
            if(stmt%bind_text(1, name) == SQLITE_OK) then
                call stmt%step_now()
            end if
        end if
        call stmt%finalize()
    
    end subroutine remove_player_db
    
    function get_player_count()
    implicit none
        
        type(sqlite3_stmt)::stmt
        integer::get_player_count
        
        get_player_count = 0
        if(stmt%prepare(db, "SELECT COUNT(*) FROM players") == SQLITE_OK) then
            if(stmt%step() == SQLITE_ROW) then
                get_player_count = stmt%column_int(0)
            end if
        end if
        call stmt%finalize()
        
    end function get_player_count
    
    function get_player_names() result(res)
    implicit none
        
        type(sqlite3_stmt)::stmt
        character(len=PLAYER_NAME_LENGTH), dimension(:), pointer::res
        integer::i,n
        
        n = get_player_count()
        if(n > 0) then
            allocate(res(n))
            if(stmt%prepare(db, "SELECT name FROM players ORDER BY name") == SQLITE_OK) then
                i = 1
                do while(stmt%step() == SQLITE_ROW .and. i <= n) 
                    call stmt%column_text(0, res(i))
                    i = i + 1
                end do
            end if
            call stmt%finalize()
            
        end if
        
    end function get_player_names
    
    function get_instuctions_count()
    implicit none
        
        type(sqlite3_stmt)::stmt
        integer::get_instuctions_count
        
        get_instuctions_count = 0
        if(stmt%prepare(db, "SELECT COUNT(*) FROM instructions") == SQLITE_OK) then
            if(stmt%step() == SQLITE_ROW) then
                get_instuctions_count = stmt%column_int(0)
            end if
        end if
        call stmt%finalize()
        
    end function get_instuctions_count
    
    function get_instruction_names() result(res)
    implicit none
        
        type(sqlite3_stmt)::stmt
        character(len=PLAYER_NAME_LENGTH), dimension(:), pointer::res
        integer::i,n
        
        n = get_instuctions_count()
        if(n > 0) then
            allocate(res(n))
            if(stmt%prepare(db, "SELECT name FROM instructions ORDER BY name") == SQLITE_OK) then
                i = 1
                do while(stmt%step() == SQLITE_ROW .and. i <= n) 
                    call stmt%column_text(0, res(i))
                    i = i + 1
                end do
            end if
            call stmt%finalize()
            
        end if
        
    end function get_instruction_names
    
    function get_jobs_count()
    implicit none

        type(sqlite3_stmt)::stmt
        integer::get_jobs_count
        
        get_jobs_count = 0
        if(stmt%prepare(db, "SELECT COUNT(*) FROM jobs") == SQLITE_OK) then
            if(stmt%step() == SQLITE_ROW) then
                get_jobs_count = stmt%column_int(0)
            end if
        end if
        call stmt%finalize()
    
    end function get_jobs_count
    
    subroutine get_player_name(id, str)
    implicit none
    
        integer, intent(in)::id
        character(*), intent(out)::str
        
        type(sqlite3_stmt)::stmt

        str = " "

        if(stmt%prepare(db, "SELECT name FROM players WHERE id=?") == SQLITE_OK) then
            if(stmt%bind_int(1, id) == SQLITE_OK) then
                if(stmt%step() == SQLITE_ROW) then
                    call stmt%column_text(0,str)
                end if
            end if
        end if
        call stmt%finalize()
        
    end subroutine get_player_name
    
    function get_player_id(name)
    implicit none
    
        integer::get_player_id
        character(*), intent(in)::name
        
        type(sqlite3_stmt)::stmt

        get_player_id = -1

        if(stmt%prepare(db, "SELECT id FROM players WHERE name=?") == SQLITE_OK) then
            if(stmt%bind_text(1, name) == SQLITE_OK) then
                if(stmt%step() == SQLITE_ROW) then
                    get_player_id = stmt%column_int(0)
                end if
            end if
        end if
        call stmt%finalize()
        
    end function get_player_id
    
    subroutine get_instruction_name(id, str)
    implicit none
    
        integer, intent(in)::id
        character(*), intent(out)::str
        
        type(sqlite3_stmt)::stmt

        str = " "

        if(stmt%prepare(db, "SELECT name FROM instructions WHERE id=?") == SQLITE_OK) then
            if(stmt%bind_int(1, id) == SQLITE_OK) then
                if(stmt%step() == SQLITE_ROW) then
                    call stmt%column_text(0,str)
                end if
            end if
        end if
        call stmt%finalize()
        
    end subroutine get_instruction_name
    
    function get_instruction_id(name)
    implicit none
    
        integer::get_instruction_id
        character(*), intent(in)::name
        
        type(sqlite3_stmt)::stmt

        get_instruction_id = -1

        if(stmt%prepare(db, "SELECT id FROM instructions WHERE name=?") == SQLITE_OK) then
            if(stmt%bind_text(1, name) == SQLITE_OK) then
                if(stmt%step() == SQLITE_ROW) then
                    get_instruction_id = stmt%column_int(0)
                end if
            end if
        end if
        call stmt%finalize()
        
    end function get_instruction_id
    
    function get_jobs() result(jobs)
    implicit none
    
        type(job), dimension(:), pointer::jobs
        type(sqlite3_stmt)::stmt
        integer::i, n
        
        n = get_jobs_count()
        jobs => null()
        
        if(n > 0) then
            allocate(jobs(n))
            if(stmt%prepare(db, "SELECT id,instruction,player,status,time  FROM jobs ORDER BY id DESC") == SQLITE_OK) then
                i = 1
                do while(stmt%step() == SQLITE_ROW .and. i <= n) 
                    jobs(i)%id = stmt%column_int(0)
                    jobs(i)%instruction = stmt%column_int(1)
                    jobs(i)%player = stmt%column_int(2)
                    jobs(i)%status = stmt%column_int(3)
                    call stmt%column_text(4, jobs(i)%time)
                    i = i + 1
                end do
            end if
            call stmt%finalize()
        end if
    
    end function get_jobs
    
    function get_jobs_for_instruction(id) result(jobs)
    implicit none
    
        type(job), dimension(:), pointer::jobs
        integer, intent(in)::id
        type(sqlite3_stmt)::stmt
    
        integer::n, i
        
        jobs => null()
        n = 0
        if(stmt%prepare(db, "SELECT COUNT(*) FROM jobs WHERE instruction=?") == SQLITE_OK) then
            if(stmt%bind_int(1, id) == SQLITE_OK) then
                if(stmt%step() == SQLITE_ROW) then
                    n = stmt%column_int(0)
                end if
            end if
        end if
        call stmt%finalize()
        
        if(n > 0) then
            allocate(jobs(n))
            if(stmt%prepare(db, &
               "SELECT id,player,status,time FROM jobs WHERE instruction=? ORDER BY id DESC") &
                   == SQLITE_OK) then
                   
                if(stmt%bind_int(1, id) == SQLITE_OK) then
                    i = 1
                    do while(stmt%step() == SQLITE_ROW .and. i <= n) 
                        jobs(i)%id = stmt%column_int(0)
                        jobs(i)%instruction = id
                        jobs(i)%player = stmt%column_int(1)
                        jobs(i)%status = stmt%column_int(2)
                        call stmt%column_text(3, jobs(i)%time)
                        i = i + 1
                    end do
                end if
                
            end if
            call stmt%finalize()
        
        end if
    
    end function get_jobs_for_instruction
    
    function is_player_busy_by_id(id)
    implicit none

        logical::is_player_busy_by_id
        integer, intent(in)::id
        type(sqlite3_stmt)::stmt
        
        is_player_busy_by_id = .false.

        if(stmt%prepare(db, "SELECT COUNT(*) FROM jobs WHERE player=? AND status=?") == SQLITE_OK) then
            if(stmt%bind_int(1, id) == SQLITE_OK .and. stmt%bind_int(2, JOB_STATUS_WORKING) == SQLITE_OK) then
                if(stmt%step() == SQLITE_ROW) then
                    is_player_busy_by_id = (stmt%column_int(0) > 0)
                end if
            end if
        end if
        call stmt%finalize()
    
    end function is_player_busy_by_id
    
    function is_player_busy_by_name(name)
    implicit none

        logical::is_player_busy_by_name
        character(*), intent(in)::name
        integer::id
        
        is_player_busy_by_name = .false.
        id = get_player_id(name)
        is_player_busy_by_name = is_player_busy_by_id(id)
    
    end function is_player_busy_by_name
    
    function get_instruction_players(id) result(res)
    implicit none
    
        integer, dimension(:), pointer::res
        integer, intent(in)::id
        type(sqlite3_stmt)::stmt
        integer::n, i
        
        res => null()
        if(stmt%prepare(db, "SELECT COUNT(*) FROM available WHERE instruction=?") == SQLITE_OK) then
            if(stmt%bind_int(1, id) == SQLITE_OK) then
                if(stmt%step() == SQLITE_ROW) then
                    n = stmt%column_int(0)
                end if
            end if
        end if
        call stmt%finalize()
    
        if(n > 0) then
            allocate(res(n))
            res = -1
            if(stmt%prepare(db, "SELECT player FROM available WHERE instruction=?") == SQLITE_OK) then
                if(stmt%bind_int(1, id) == SQLITE_OK) then
                    i = 1
                    do while(stmt%step() == SQLITE_ROW .and. i <= n)
                        res(i) = stmt%column_int(0)
                        i = i + 1
                    end do
                end if
            end if
            call stmt%finalize()
        end if
    
    end function get_instruction_players
    
    subroutine add_player_for_instruction(instruction, player)
    implicit none
    
        integer, intent(in)::instruction, player
        type(sqlite3_stmt)::stmt
        
        if(stmt%prepare(db, "INSERT OR IGNORE INTO available(instruction, player) VALUES(?,?)") == SQLITE_OK) then
            if(stmt%bind_int(1, instruction) == SQLITE_OK .and. stmt%bind_int(2, player) == SQLITE_OK) then
                call stmt%step_now()
            end if
        end if
        call stmt%finalize()
    
    end subroutine add_player_for_instruction
    
    subroutine remove_player_for_instruction(instruction, player)
    implicit none
    
        integer, intent(in)::instruction, player
        type(sqlite3_stmt)::stmt
        
        if(stmt%prepare(db, "DELETE FROM available WHERE instruction=? AND player=?") == SQLITE_OK) then
            if(stmt%bind_int(1, instruction) == SQLITE_OK .and. stmt%bind_int(2, player) == SQLITE_OK) then
                call stmt%step_now()
            end if
        end if
        call stmt%finalize()
    
    end subroutine remove_player_for_instruction
    
    subroutine scan_instructions_for_db()
    use config
    use utilities
    use logging
    implicit none
        
        character(len=2048)::cmdline
        
        call combine_paths(script_dir, "scan_instructions.sh", cmdline)
        cmdline = trim(cmdline)//" "//trim(database_file)//" "//trim(instructions_dir)//" 1>/dev/null 2>/dev/null"
        
        call write_log("Scan Command: "//trim(cmdline))
        call execute_command_line(trim(cmdline), wait=.true.)
        
    end subroutine scan_instructions_for_db
    
end module captain_db