package tui

import (
	"encoding/json"
	"fmt"
	"strings"
)

type runStep struct {
	Text string `json:"text"`
	Done bool   `json:"done"`
}

type runModel struct {
	steps    []runStep
	cursor   int
	entityID string
	dirty    bool
}

func newRunModel(entityID string, cardData *string) runModel {
	m := runModel{entityID: entityID}
	m.steps = parseChecklist(cardData)
	return m
}

func parseChecklist(cardData *string) []runStep {
	if cardData == nil {
		return nil
	}
	var data struct {
		Steps []runStep `json:"steps"`
	}
	if err := json.Unmarshal([]byte(*cardData), &data); err != nil {
		return nil
	}
	return data.Steps
}

func (r runModel) stepsJSON() string {
	b, _ := json.Marshal(map[string]any{"steps": r.steps})
	return string(b)
}

func (r runModel) doneCount() int {
	n := 0
	for _, s := range r.steps {
		if s.Done {
			n++
		}
	}
	return n
}

func (r runModel) update(key string) runModel {
	switch key {
	case "up", "k":
		if r.cursor > 0 {
			r.cursor--
		}
	case "down", "j":
		if r.cursor < len(r.steps)-1 {
			r.cursor++
		}
	case " ":
		if r.cursor < len(r.steps) {
			r.steps[r.cursor].Done = !r.steps[r.cursor].Done
			r.dirty = true
		}
	case "r":
		for i := range r.steps {
			r.steps[i].Done = false
		}
		r.dirty = true
	}
	return r
}

func (r runModel) view(width int) string {
	if len(r.steps) == 0 {
		return statusStyle.Render("no steps")
	}

	var b strings.Builder
	done := r.doneCount()
	total := len(r.steps)
	pct := 0
	if total > 0 {
		pct = done * 100 / total
	}

	header := fmt.Sprintf("▶ running   %d/%d done (%d%%)", done, total, pct)
	b.WriteString(detailHeaderStyle.Render(header))
	b.WriteString("\n\n")

	for i, step := range r.steps {
		var line string
		if step.Done {
			line = checkDoneStyle.Render("[✓] " + step.Text)
		} else {
			line = checkPendingStyle.Render("[ ] " + step.Text)
		}

		if i == r.cursor {
			b.WriteString(selectedItemStyle.Render(" " + line))
		} else {
			b.WriteString(listItemStyle.Render(line))
		}
		b.WriteString("\n")
	}

	b.WriteString("\n")
	b.WriteString(helpStyle.Render("space:toggle  r:reset  esc:save+exit"))

	return b.String()
}