package tui

import (
	"fmt"

	"code.humancabbage.net/sam/moonmath/coindesk"
	"code.humancabbage.net/sam/moonmath/config"
	"code.humancabbage.net/sam/moonmath/tui/asset"
	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/lipgloss"
)

type Model struct {
	assets []asset.Model
}

func New(assets []coindesk.Asset, cfg config.All) (p *tea.Program) {
	model := newModel(assets, cfg)
	p = tea.NewProgram(
		model,
		tea.WithAltScreen(),
		tea.WithFPS(30),
	)
	return
}

func newModel(assets []coindesk.Asset, cfg config.All) (m Model) {
	// construct models for each asset, but don't filter out dupes
	seen := map[coindesk.Asset]struct{}{}
	for _, a := range assets {
		_, ok := seen[a]
		if ok {
			continue
		}
		assetCfg := cfg.GetData(a)
		assetModel := asset.New(assetCfg)
		m.assets = append(m.assets, assetModel)
		seen[a] = struct{}{}
	}
	return
}

func (m Model) Init() tea.Cmd {
	// initialize child models, collecting their commands,
	// then return them all in a batch
	var inits []tea.Cmd
	for i := range m.assets {
		cmd := m.assets[i].Init()
		inits = append(inits, cmd)
	}
	return tea.Batch(inits...)
}

func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
	switch msg := msg.(type) {
	// handle keys for quitting
	case tea.KeyMsg:
		switch msg.String() {
		case "ctrl+c", "q", "esc":
			return m, tea.Quit
		}
	// forward asset messages to the appropriate model
	case asset.Msg:
		cmd := m.forward(msg.Asset, msg)
		return m, cmd
	// forward any other message to each child model.
	// typically, this is for animation.
	default:
		var commands []tea.Cmd
		for i := range m.assets {
			var cmd tea.Cmd
			m.assets[i], cmd = m.assets[i].Update(msg)
			commands = append(commands, cmd)
		}
		return m, tea.Batch(commands...)
	}
	return m, nil
}

func (m Model) View() string {
	var ss []string
	for i := range m.assets {
		s := m.assets[i].View()
		ss = append(ss, s)
	}
	r := lipgloss.JoinVertical(lipgloss.Center, ss...)
	return r
}

func (m Model) forward(a coindesk.Asset, msg tea.Msg) (cmd tea.Cmd) {
	// O(n) is fine when n is small
	for i := range m.assets {
		if !m.assets[i].Handles(a) {
			continue
		}
		m.assets[i], cmd = m.assets[i].Update(msg)
		return
	}
	panic(fmt.Errorf("rogue message: %v", msg))
}