//
//  rhctl
//
//  Copyright (C) 2009-2016 Christian Pointner <equinox@helsinki.at>
//
//  This file is part of rhctl.
//
//  rhctl 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
//  any later version.
//
//  rhctl 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 rhctl. If not, see <http://www.gnu.org/licenses/>.
//

package main

import (
	"fmt"
	"strconv"
	"strings"
)

const (
	SwitchUnitIDMax    SwitchUnitID    = 3
	SwitchInputNumMax  SwitchInputNum  = 8
	SwitchOutputNumMax SwitchOutputNum = 2
	SwitchGPINumMax    SwitchGPINum    = 16
	SwitchRelayNumMax  SwitchRelayNum  = 8
	SwitchOCNumMax     SwitchOCNum     = 8
)

type SwitchUnitID uint

func (u SwitchUnitID) String() string {
	return strconv.FormatUint(uint64(u), 10)
}

func (u *SwitchUnitID) FromString(str string) error {
	vuint, err := strconv.ParseUint(str, 10, 32)
	if err != nil {
		return err
	}
	if vuint > uint64(SwitchUnitIDMax) {
		return fmt.Errorf("switch unit ID is out of range")
	}
	*u = SwitchUnitID(vuint)
	return nil
}

func (u *SwitchUnitID) UnmarshalTOML(data []byte) error {
	return u.FromString(string(data))
}

type SwitchInputNum uint

func (i SwitchInputNum) String() string {
	return strconv.FormatUint(uint64(i), 10)
}

func (i *SwitchInputNum) FromString(str string) error {
	vuint, err := strconv.ParseUint(str, 10, 32)
	if err != nil {
		return err
	}
	if vuint < 1 || vuint > uint64(SwitchInputNumMax) {
		return fmt.Errorf("switch input number is out of range")
	}
	*i = SwitchInputNum(vuint)
	return nil
}

func (i *SwitchInputNum) UnmarshalTOML(data []byte) error {
	return i.FromString(string(data))
}

type SwitchOutputNum uint

func (o SwitchOutputNum) String() string {
	return strconv.FormatUint(uint64(o), 10)
}

func (o *SwitchOutputNum) FromString(str string) error {
	vuint, err := strconv.ParseUint(str, 10, 32)
	if err != nil {
		return err
	}
	if vuint < 1 || vuint > uint64(SwitchOutputNumMax) {
		return fmt.Errorf("switch output number is out of range")
	}
	*o = SwitchOutputNum(vuint)
	return nil
}

type SwitchGPINum uint

func (g SwitchGPINum) String() string {
	return strconv.FormatUint(uint64(g), 10)
}

func (g *SwitchGPINum) FromString(str string) error {
	vuint, err := strconv.ParseUint(str, 10, 32)
	if err != nil {
		return err
	}
	if vuint < 1 || vuint > uint64(SwitchGPINumMax) {
		return fmt.Errorf("switch GPI number is out of range")
	}
	*g = SwitchGPINum(vuint)
	return nil
}

type SwitchRelayNum uint

func (r SwitchRelayNum) String() string {
	return strconv.FormatUint(uint64(r), 10)
}

func (r *SwitchRelayNum) FromString(str string) error {
	vuint, err := strconv.ParseUint(str, 10, 32)
	if err != nil {
		return err
	}
	if vuint < 1 || vuint > uint64(SwitchRelayNumMax) {
		return fmt.Errorf("switch relay number is out of range")
	}
	*r = SwitchRelayNum(vuint)
	return nil
}

type SwitchOCNum uint

func (o SwitchOCNum) String() string {
	return strconv.FormatUint(uint64(o), 10)
}

func (o *SwitchOCNum) FromString(str string) error {
	vuint, err := strconv.ParseUint(str, 10, 32)
	if err != nil {
		return err
	}
	if vuint < 1 || vuint > uint64(SwitchOCNumMax) {
		return fmt.Errorf("switch OC number is out of range")
	}
	*o = SwitchOCNum(vuint)
	return nil
}

type SwitchCmdString string

const (
	SwitchCmdStateAudio   SwitchCmdString = "*uSL"
	SwitchCmdStateSilence SwitchCmdString = "*uSS"
	SwitchCmdStateGPI     SwitchCmdString = "*uSPgg"
	SwitchCmdStateGPIAll  SwitchCmdString = "*uSPA"
	SwitchCmdStateRelay   SwitchCmdString = "*uSR"
	SwitchCmdStateOC      SwitchCmdString = "*uSO"

	SwitchCmdAudioApplyInput       SwitchCmdString = "*uiio"
	SwitchCmdAudioApplyInputAll    SwitchCmdString = "*uiiA"
	SwitchCmdAudioAddInputTo1      SwitchCmdString = "*uii3"
	SwitchCmdAudioAddInputTo2      SwitchCmdString = "*uii4"
	SwitchCmdAudioRemoveInputFrom1 SwitchCmdString = "*uii5"
	SwitchCmdAudioRemoveInputFrom2 SwitchCmdString = "*uii6"
	SwitchCmdAudioMuteInput        SwitchCmdString = "*uiiMo"
	SwitchCmdAudioMuteInputAll     SwitchCmdString = "*uiiMA"
	SwitchCmdAudioMuteOutput       SwitchCmdString = "*uMo"
	SwitchCmdAudioMuteOutputAll    SwitchCmdString = "*uMA"
	SwitchCmdAudioFadeUpInput      SwitchCmdString = "*uFUii"
	SwitchCmdAudioFadeDownInput    SwitchCmdString = "*uFDii"

	SwitchCmdOCUnlatch SwitchCmdString = "*uOOcF"
	SwitchCmdOCLatch   SwitchCmdString = "*uOOcL"
	SwitchCmdOCPulse   SwitchCmdString = "*uOOcP"

	SwitchCmdRelayUnlatch SwitchCmdString = "*uORrF"
	SwitchCmdRelayLatch   SwitchCmdString = "*uORrL"
	SwitchCmdRelayPulse   SwitchCmdString = "*uORrP"
)

func (c SwitchCmdString) Generate(args ...interface{}) (string, error) {
	s := string(c)
	for _, arg := range args {
		switch arg.(type) {
		case SwitchUnitID:
			if arg.(SwitchUnitID) > SwitchUnitIDMax {
				return "", fmt.Errorf("switch unit ID is out of range")
			}
			s = strings.Replace(s, "u", fmt.Sprintf("%1d", arg.(SwitchUnitID)), -1)
		case SwitchInputNum:
			if arg.(SwitchInputNum) < 1 || arg.(SwitchInputNum) > SwitchInputNumMax {
				return "", fmt.Errorf("switch input number is out of range")
			}
			s = strings.Replace(s, "ii", fmt.Sprintf("%02d", arg.(SwitchInputNum)), -1)
		case SwitchOutputNum:
			if arg.(SwitchOutputNum) < 1 || arg.(SwitchOutputNum) > SwitchOutputNumMax {
				return "", fmt.Errorf("switch input number is out of range")
			}
			s = strings.Replace(s, "o", fmt.Sprintf("%1d", arg.(SwitchOutputNum)), -1)
		case SwitchGPINum:
			if arg.(SwitchGPINum) < 1 || arg.(SwitchGPINum) > SwitchGPINumMax {
				return "", fmt.Errorf("switch GPI number is out of range")
			}
			s = strings.Replace(s, "gg", fmt.Sprintf("%02d", arg.(SwitchGPINum)), -1)
		case SwitchRelayNum:
			if arg.(SwitchRelayNum) < 1 || arg.(SwitchRelayNum) > SwitchRelayNumMax {
				return "", fmt.Errorf("switch relay number is out of range")
			}
			s = strings.Replace(s, "r", fmt.Sprintf("%1d", arg.(SwitchRelayNum)), -1)
		case SwitchOCNum:
			if arg.(SwitchOCNum) < 1 || arg.(SwitchOCNum) > SwitchOCNumMax {
				return "", fmt.Errorf("switch OC number is out of range")
			}
			s = strings.Replace(s, "c", fmt.Sprintf("%1d", arg.(SwitchOCNum)), -1)
		}
	}
	return s, nil
}

type SwitchCommand struct {
	Cmd      SwitchCmdString
	Args     []interface{}
	Response chan<- interface{}
}

func SwitchCommandParseState(args []string) (cmdstr SwitchCmdString, cmdargs []interface{}, err error) {
	if len(args) == 0 {
		err = fmt.Errorf("missing argument <state-type>")
		return
	}
	switch strings.ToLower(args[0]) {
	case "audio":
		cmdstr = SwitchCmdStateAudio
	case "silence":
		cmdstr = SwitchCmdStateSilence
	case "gpi":
		cmdstr = SwitchCmdStateGPIAll
	case "relay":
		cmdstr = SwitchCmdStateRelay
	case "oc":
		cmdstr = SwitchCmdStateOC
	default:
		err = fmt.Errorf("unknown state-type: '%s'", args[0])
		return
	}
	return
}

func SwitchCommandParseAudio(args []string) (cmdstr SwitchCmdString, cmdargs []interface{}, err error) {
	if len(args) < 2 || len(args) > 3 {
		err = fmt.Errorf("wrong number of arguments")
		return
	}

	onum := SwitchOutputNum(0)
	if strings.ToLower(args[0]) != "all" {
		if err = onum.FromString(args[0]); err != nil {
			return
		}
		cmdargs = append(cmdargs, onum)
	}

	inum := SwitchInputNum(0)
	if len(args) == 3 {
		if err = inum.FromString(args[2]); err != nil {
			return
		}
		cmdargs = append(cmdargs, inum)
	}

	switch strings.ToLower(args[1]) {
	case "apply":
		if len(args) != 3 {
			err = fmt.Errorf("wrong number of arguments")
			return
		}
		if onum == 0 {
			cmdstr = SwitchCmdAudioApplyInputAll
		} else {
			cmdstr = SwitchCmdAudioApplyInput
		}
	case "add":
		if len(args) != 3 {
			err = fmt.Errorf("wrong number of arguments")
			return
		}
		switch onum {
		case 1:
			cmdstr = SwitchCmdAudioAddInputTo1
		case 2:
			cmdstr = SwitchCmdAudioAddInputTo2
		default:
			err = fmt.Errorf("this operation cannot be applied to all outputs")
			return
		}
	case "remove":
		if len(args) != 3 {
			err = fmt.Errorf("wrong number of arguments")
			return
		}
		switch onum {
		case 1:
			cmdstr = SwitchCmdAudioRemoveInputFrom1
		case 2:
			cmdstr = SwitchCmdAudioRemoveInputFrom2
		default:
			err = fmt.Errorf("this operation cannot be applied to all outputs")
			return
		}
	case "up":
		if len(args) != 3 {
			err = fmt.Errorf("wrong number of arguments")
			return
		}
		if onum != 1 {
			err = fmt.Errorf("this operation is only allowed on output 1")
			return
		}
		cmdstr = SwitchCmdAudioFadeUpInput
	case "down":
		if len(args) != 3 {
			err = fmt.Errorf("wrong number of arguments")
			return
		}
		if onum != 1 {
			err = fmt.Errorf("this operation is only allowed on output 1")
			return
		}
		cmdstr = SwitchCmdAudioFadeDownInput
	case "mute":
		if len(args) == 3 {
			if onum == 0 {
				cmdstr = SwitchCmdAudioMuteInputAll
			} else {
				cmdstr = SwitchCmdAudioMuteInput
			}
		} else {
			if onum == 0 {
				cmdstr = SwitchCmdAudioMuteOutputAll
			} else {
				cmdstr = SwitchCmdAudioMuteOutput
			}
		}
	default:
		err = fmt.Errorf("unknown operation: '%s', must be one of latch, unlatch, pulse", args[1])
		return
	}
	return
}

func SwitchCommandParseRelay(args []string) (cmdstr SwitchCmdString, cmdargs []interface{}, err error) {
	if len(args) != 2 {
		err = fmt.Errorf("wrong number of arguments, expecting: <relay-num> (latch|unlatch|pulse)")
		return
	}
	var num SwitchRelayNum
	if err = num.FromString(args[0]); err != nil {
		return
	}
	cmdargs = append(cmdargs, num)
	switch strings.ToLower(args[1]) {
	case "latch":
		cmdstr = SwitchCmdRelayLatch
	case "unlatch":
		cmdstr = SwitchCmdRelayUnlatch
	case "pulse":
		cmdstr = SwitchCmdRelayPulse
	default:
		err = fmt.Errorf("unknown operation: '%s', must be one of latch, unlatch, pulse", args[1])
		return
	}
	return
}

func SwitchCommandParseOC(args []string) (cmdstr SwitchCmdString, cmdargs []interface{}, err error) {
	if len(args) != 2 {
		err = fmt.Errorf("wrong number of arguments, expecting: <oc-num> (latch|unlatch|pulse)")
		return
	}
	var num SwitchOCNum
	if err = num.FromString(args[0]); err != nil {
		return
	}
	cmdargs = append(cmdargs, num)
	switch strings.ToLower(args[1]) {
	case "latch":
		cmdstr = SwitchCmdOCLatch
	case "unlatch":
		cmdstr = SwitchCmdOCUnlatch
	case "pulse":
		cmdstr = SwitchCmdOCPulse
	default:
		err = fmt.Errorf("unknown operation: '%s', must be one of latch, unlatch, pulse", args[1])
		return
	}
	return
}

func SwitchCommandHelp() []string {
	return []string{
		"state <state-type>",
		" request status update. The following types are allowed:",
		"  - audio     audio input/ouput routings",
		"  - gpi       state of general purpose inputs",
		"  - oc        state of open-collector outputs",
		"  - relay     state of relay outputs",
		"  - silence   output silence monitor state",
		"",
		"out <num> <cmd> [ <input> ]",
		" change audio input/output routings.",
		" <num> specifies the audio output: one of 1, 2, all ",
		" Commands:",
		"  - apply <input>     simulate select button press",
		"  - add <input>       add <input> to output routing",
		"  - remove <input>    remove <input> from output routing",
		"  - up <input>        fade up <input> (only allowed for output 1)",
		"  - down <input>      fade down <input> (only allowed for output 1)",
		"  - mute [ <input> ]  mute <input> or whole <output>",
		"",
		"relay <num> (latch|unlatch|pulse)",
		" Control open-collector outputs.",
		"",
		"oc <num> (latch|unlatch|pulse)",
		" Control relay outputs.",
		"",
	}
}

func NewSwitchCommandFromStrings(cmd string, args ...string) (c *SwitchCommand, err error) {
	c = &SwitchCommand{}
	switch strings.ToLower(cmd) {
	case "state":
		c.Cmd, c.Args, err = SwitchCommandParseState(args)
	case "out":
		c.Cmd, c.Args, err = SwitchCommandParseAudio(args)
	case "relay":
		c.Cmd, c.Args, err = SwitchCommandParseRelay(args)
	case "oc":
		c.Cmd, c.Args, err = SwitchCommandParseOC(args)
	default:
		return nil, fmt.Errorf("unknown command '%s'", cmd)
	}
	return
}