package controller

import (
	"fmt"
	"time"

	"github.com/charmbracelet/bubbles/key"
	"github.com/charmbracelet/bubbles/list"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/jfraeys/fetch_ml/cmd/tui/internal/config"
	"github.com/jfraeys/fetch_ml/cmd/tui/internal/model"
	"github.com/jfraeys/fetch_ml/cmd/tui/internal/services"
	"github.com/jfraeys/fetch_ml/internal/logging"
)

// Controller handles all business logic and state updates
type Controller struct {
	config    *config.Config
	server    *services.MLServer
	taskQueue *services.TaskQueue
	logger    *logging.Logger
}

func (c *Controller) handleKeyMsg(msg tea.KeyMsg, m model.State) (model.State, tea.Cmd) {
	if m.InputMode {
		return c.handleInputModeKey(msg, m)
	}

	if m.ActiveView == model.ViewModeSettings {
		return c.handleSettingsKeys(msg, m)
	}

	if key.Matches(msg, m.Keys.Quit) {
		return m, tea.Quit
	}

	cmds := c.handleGlobalKeys(msg, &m)
	return c.finalizeUpdate(msg, m, cmds...)
}

func (c *Controller) handleInputModeKey(msg tea.KeyMsg, m model.State) (model.State, tea.Cmd) {
	switch msg.String() {
	case "enter":
		args := m.Input.Value()
		m.Input.SetValue("")
		m.InputMode = false
		if job := getSelectedJob(m); job != nil {
			return m, c.queueJob(job.Name, args)
		}
		return m, nil
	case "esc":
		m.InputMode = false
		m.Input.SetValue("")
		return m, nil
	default:
		var cmd tea.Cmd
		m.Input, cmd = m.Input.Update(msg)
		return m, cmd
	}
}

func (c *Controller) handleSettingsKeys(msg tea.KeyMsg, m model.State) (model.State, tea.Cmd) {
	cmds := c.navigateSettings(msg, &m)
	if m.SettingsIndex == 1 {
		var inputCmd tea.Cmd
		m.APIKeyInput, inputCmd = m.APIKeyInput.Update(msg)
		cmds = append(cmds, inputCmd, c.updateSettingsContent(m))
	}
	return m, tea.Batch(cmds...)
}

func (c *Controller) navigateSettings(msg tea.KeyMsg, m *model.State) []tea.Cmd {
	var cmds []tea.Cmd
	switch msg.String() {
	case "up", "k":
		if m.SettingsIndex > 1 {
			m.SettingsIndex--
			cmds = append(cmds, c.updateSettingsContent(*m))
			c.toggleAPIKeyInputFocus(m)
		}
	case "down", "j":
		if m.SettingsIndex < 2 {
			m.SettingsIndex++
			cmds = append(cmds, c.updateSettingsContent(*m))
			c.toggleAPIKeyInputFocus(m)
		}
	case "enter":
		if cmd := c.handleSettingsAction(m); cmd != nil {
			cmds = append(cmds, cmd)
		}
	case "esc":
		m.ActiveView = model.ViewModeJobs
		m.APIKeyInput.Blur()
	}
	return cmds
}

func (c *Controller) toggleAPIKeyInputFocus(m *model.State) {
	if m.SettingsIndex == 1 {
		m.APIKeyInput.Focus()
	} else {
		m.APIKeyInput.Blur()
	}
}

func (c *Controller) handleGlobalKeys(msg tea.KeyMsg, m *model.State) []tea.Cmd {
	var cmds []tea.Cmd

	switch {
	case key.Matches(msg, m.Keys.Refresh):
		m.IsLoading = true
		m.Status = "Refreshing all data..."
		m.LastRefresh = time.Now()
		cmds = append(cmds, c.loadAllData())
	case key.Matches(msg, m.Keys.RefreshGPU):
		m.Status = "Refreshing GPU status..."
		cmds = append(cmds, c.loadGPU())
	case key.Matches(msg, m.Keys.Trigger):
		if job := getSelectedJob(*m); job != nil {
			cmds = append(cmds, c.queueJob(job.Name, ""))
		}
	case key.Matches(msg, m.Keys.TriggerArgs):
		if job := getSelectedJob(*m); job != nil {
			m.InputMode = true
			m.Input.Focus()
		}
	case key.Matches(msg, m.Keys.ViewQueue):
		m.ActiveView = model.ViewModeQueue
		cmds = append(cmds, c.showQueue(*m))
	case key.Matches(msg, m.Keys.ViewContainer):
		m.ActiveView = model.ViewModeContainer
		cmds = append(cmds, c.loadContainer())
	case key.Matches(msg, m.Keys.ViewGPU):
		m.ActiveView = model.ViewModeGPU
		cmds = append(cmds, c.loadGPU())
	case key.Matches(msg, m.Keys.ViewJobs):
		m.ActiveView = model.ViewModeJobs
	case key.Matches(msg, m.Keys.ViewSettings):
		m.ActiveView = model.ViewModeSettings
		m.SettingsIndex = 1
		m.APIKeyInput.Focus()
		cmds = append(cmds, c.updateSettingsContent(*m))
	case key.Matches(msg, m.Keys.ViewExperiments):
		m.ActiveView = model.ViewModeExperiments
		cmds = append(cmds, c.loadExperiments())
	case key.Matches(msg, m.Keys.Cancel):
		if job := getSelectedJob(*m); job != nil && job.TaskID != "" {
			cmds = append(cmds, c.cancelTask(job.TaskID))
		}
	case key.Matches(msg, m.Keys.Delete):
		if job := getSelectedJob(*m); job != nil && job.Status == model.StatusPending {
			cmds = append(cmds, c.deleteJob(job.Name))
		}
	case key.Matches(msg, m.Keys.MarkFailed):
		if job := getSelectedJob(*m); job != nil && job.Status == model.StatusRunning {
			cmds = append(cmds, c.markFailed(job.Name))
		}
	case key.Matches(msg, m.Keys.Help):
		m.ShowHelp = !m.ShowHelp
	}

	return cmds
}

func (c *Controller) applyWindowSize(msg tea.WindowSizeMsg, m model.State) model.State {
	m.Width = msg.Width
	m.Height = msg.Height

	h, v := 4, 2
	listHeight := msg.Height - v - 8
	m.JobList.SetSize(msg.Width/3-h, listHeight)

	panelWidth := msg.Width*2/3 - h - 2
	panelHeight := (listHeight - 6) / 3

	m.GpuView.Width = panelWidth
	m.GpuView.Height = panelHeight
	m.ContainerView.Width = panelWidth
	m.ContainerView.Height = panelHeight
	m.QueueView.Width = panelWidth
	m.QueueView.Height = listHeight - 4
	m.SettingsView.Width = panelWidth
	m.SettingsView.Height = listHeight - 4
	m.ExperimentsView.Width = panelWidth
	m.ExperimentsView.Height = listHeight - 4

	return m
}

func (c *Controller) handleJobsLoadedMsg(msg JobsLoadedMsg, m model.State) (model.State, tea.Cmd) {
	m.Jobs = []model.Job(msg)
	calculateJobStats(&m)

	items := make([]list.Item, len(m.Jobs))
	for i, job := range m.Jobs {
		items[i] = job
	}

	setItemsCmd := m.JobList.SetItems(items)
	m.Status = formatStatus(m)
	m.IsLoading = false
	return c.finalizeUpdate(msg, m, setItemsCmd)
}

func (c *Controller) handleTasksLoadedMsg(
	msg TasksLoadedMsg,
	m model.State,
) (model.State, tea.Cmd) {
	m.QueuedTasks = []*model.Task(msg)
	m.Status = formatStatus(m)
	return c.finalizeUpdate(msg, m)
}

func (c *Controller) handleGPUContent(msg GpuLoadedMsg, m model.State) (model.State, tea.Cmd) {
	m.GpuView.SetContent(string(msg))
	m.GpuView.GotoTop()
	return c.finalizeUpdate(msg, m)
}

func (c *Controller) handleContainerContent(
	msg ContainerLoadedMsg,
	m model.State,
) (model.State, tea.Cmd) {
	m.ContainerView.SetContent(string(msg))
	m.ContainerView.GotoTop()
	return c.finalizeUpdate(msg, m)
}

func (c *Controller) handleQueueContent(msg QueueLoadedMsg, m model.State) (model.State, tea.Cmd) {
	m.QueueView.SetContent(string(msg))
	m.QueueView.GotoTop()
	return c.finalizeUpdate(msg, m)
}

func (c *Controller) handleStatusMsg(msg StatusMsg, m model.State) (model.State, tea.Cmd) {
	if msg.Level == "error" {
		m.ErrorMsg = msg.Text
		m.Status = "Error occurred - check status"
	} else {
		m.ErrorMsg = ""
		m.Status = msg.Text
	}
	return c.finalizeUpdate(msg, m)
}

func (c *Controller) handleTickMsg(msg TickMsg, m model.State) (model.State, tea.Cmd) {
	var cmds []tea.Cmd
	if time.Since(m.LastRefresh) > 10*time.Second && !m.IsLoading {
		m.LastRefresh = time.Now()
		cmds = append(cmds, c.loadAllData())
	}
	cmds = append(cmds, tickCmd())
	return c.finalizeUpdate(msg, m, cmds...)
}

func (c *Controller) finalizeUpdate(
	msg tea.Msg,
	m model.State,
	extraCmds ...tea.Cmd,
) (model.State, tea.Cmd) {
	cmds := append([]tea.Cmd{}, extraCmds...)

	var cmd tea.Cmd
	m.JobList, cmd = m.JobList.Update(msg)
	cmds = append(cmds, cmd)

	m.GpuView, cmd = m.GpuView.Update(msg)
	cmds = append(cmds, cmd)

	m.ContainerView, cmd = m.ContainerView.Update(msg)
	cmds = append(cmds, cmd)

	m.QueueView, cmd = m.QueueView.Update(msg)
	cmds = append(cmds, cmd)

	m.ExperimentsView, cmd = m.ExperimentsView.Update(msg)
	cmds = append(cmds, cmd)

	var spinCmd tea.Cmd
	m.Spinner, spinCmd = m.Spinner.Update(msg)
	cmds = append(cmds, spinCmd)

	return m, tea.Batch(cmds...)
}

// New creates a new Controller instance
func New(
	cfg *config.Config,
	srv *services.MLServer,
	tq *services.TaskQueue,
	logger *logging.Logger,
) *Controller {
	return &Controller{
		config:    cfg,
		server:    srv,
		taskQueue: tq,
		logger:    logger,
	}
}

// Init initializes the TUI and returns initial commands
func (c *Controller) Init() tea.Cmd {
	return tea.Batch(
		tea.SetWindowTitle("FetchML"),
		c.loadAllData(),
		tickCmd(),
	)
}

// Update handles all messages and updates the state
func (c *Controller) Update(msg tea.Msg, m model.State) (model.State, tea.Cmd) {
	switch typed := msg.(type) {
	case tea.KeyMsg:
		return c.handleKeyMsg(typed, m)
	case tea.WindowSizeMsg:
		updated := c.applyWindowSize(typed, m)
		return c.finalizeUpdate(msg, updated)
	case JobsLoadedMsg:
		return c.handleJobsLoadedMsg(typed, m)
	case TasksLoadedMsg:
		return c.handleTasksLoadedMsg(typed, m)
	case GpuLoadedMsg:
		return c.handleGPUContent(typed, m)
	case ContainerLoadedMsg:
		return c.handleContainerContent(typed, m)
	case QueueLoadedMsg:
		return c.handleQueueContent(typed, m)
	case SettingsContentMsg:
		m.SettingsView.SetContent(string(typed))
		return c.finalizeUpdate(msg, m)
	case ExperimentsLoadedMsg:
		m.ExperimentsView.SetContent(string(typed))
		m.ExperimentsView.GotoTop()
		return c.finalizeUpdate(msg, m)
	case SettingsUpdateMsg:
		return c.finalizeUpdate(msg, m)
	case StatusMsg:
		return c.handleStatusMsg(typed, m)
	case TickMsg:
		return c.handleTickMsg(typed, m)
	default:
		return c.finalizeUpdate(msg, m)
	}
}

// ExperimentsLoadedMsg is sent when experiments are loaded
type ExperimentsLoadedMsg string

func (c *Controller) loadExperiments() tea.Cmd {
	return func() tea.Msg {
		commitIDs, err := c.taskQueue.ListExperiments()
		if err != nil {
			return StatusMsg{Level: "error", Text: fmt.Sprintf("Failed to list experiments: %v", err)}
		}

		if len(commitIDs) == 0 {
			return ExperimentsLoadedMsg("Experiments:\n\nNo experiments found.")
		}

		var output string
		output += "Experiments:\n\n"

		for _, commitID := range commitIDs {
			details, err := c.taskQueue.GetExperimentDetails(commitID)
			if err != nil {
				output += fmt.Sprintf("Error loading %s: %v\n\n", commitID, err)
				continue
			}
			output += details + "\n----------------------------------------\n\n"
		}

		return ExperimentsLoadedMsg(output)
	}
}