package tui

import (
    "strings"

    "charm.land/lipgloss/v2"
)

type ModalConfig struct {
    Title         string
    Content       string
    Footer        string
    Width         int
    MaxWidth      int
    BorderStyle   lipgloss.Border
    PaddingTop    int
    PaddingBottom int
    PaddingLeft   int
    PaddingRight  int
}

func DefaultModalConfig() ModalConfig {
    return ModalConfig{
        MaxWidth:      60,
        BorderStyle:   lipgloss.RoundedBorder(),
        PaddingTop:    1,
        PaddingBottom: 1,
        PaddingLeft:   2,
        PaddingRight:  2,
    }
}

func RenderModal(baseContent string, config ModalConfig, styles Styles, viewportWidth, viewportHeight int) string {
    cfg := DefaultModalConfig()
    if config.Title != "" {
        cfg.Title = config.Title
    }
    if config.Content != "" {
        cfg.Content = config.Content
    }
    if config.Footer != "" {
        cfg.Footer = config.Footer
    }
    if config.Width > 0 {
        cfg.Width = config.Width
    }
    if config.MaxWidth > 0 {
        cfg.MaxWidth = config.MaxWidth
    }
    if config.BorderStyle != (lipgloss.Border{}) {
        cfg.BorderStyle = config.BorderStyle
    }
    cfg.PaddingTop = config.PaddingTop
    cfg.PaddingBottom = config.PaddingBottom
    cfg.PaddingLeft = config.PaddingLeft
    cfg.PaddingRight = config.PaddingRight
    var b strings.Builder
    if cfg.Title != "" {
        b.WriteString(styles.OverlayTitle.Render(cfg.Title))
        b.WriteString("\n")
    }
    if cfg.Content != "" {
        b.WriteString(cfg.Content)
        if cfg.Footer != "" {
            b.WriteString("\n\n")
        }
    }
    if cfg.Footer != "" {
        b.WriteString(styles.OverlayDim.Render(cfg.Footer))
    }
    contentW := cfg.Width
    if contentW == 0 {
        lines := strings.Split(b.String(), "\n")
        for _, line := range lines {
            w := lipgloss.Width(line)
            if w+cfg.PaddingLeft+cfg.PaddingRight+2 > contentW {
                contentW = w + cfg.PaddingLeft + cfg.PaddingRight + 2
            }
        }
    }
    if contentW > cfg.MaxWidth {
        contentW = cfg.MaxWidth
    }
    if contentW < 30 {
        contentW = 30
    }
    if contentW >= viewportWidth-4 {
        contentW = viewportWidth - 4
    }
    box := lipgloss.NewStyle().
        Border(cfg.BorderStyle).
        BorderForeground(lipgloss.Color(styles.OverlayBorder)).
        Padding(cfg.PaddingTop, cfg.PaddingLeft, cfg.PaddingBottom, cfg.PaddingRight).
        Width(contentW)
    return box.Render(b.String())
}

func CenterOverlay(baseContent, overlay string, viewportWidth, viewportHeight int) string {
    baseLines := strings.Split(baseContent, "\n")
    overlayLines := strings.Split(overlay, "\n")
    startY := (len(baseLines) - len(overlayLines)) / 2
    if startY < 0 {
        startY = 0
    }
    for i, ol := range overlayLines {
        row := startY + i
        if row >= len(baseLines) {
            break
        }
        olW := lipgloss.Width(ol)
        padLeft := (viewportWidth - olW) / 2
        if padLeft < 0 {
            padLeft = 0
        }
        baseLines[row] = strings.Repeat(" ", padLeft) + ol
    }
    return strings.Join(baseLines, "\n")
}

type ModalBuilder struct {
    config ModalConfig
}

func NewModal() *ModalBuilder {
    return &ModalBuilder{config: DefaultModalConfig()}
}

func (mb *ModalBuilder) Title(title string) *ModalBuilder {
    mb.config.Title = title
    return mb
}

func (mb *ModalBuilder) Content(content string) *ModalBuilder {
    mb.config.Content = content
    return mb
}

func (mb *ModalBuilder) Footer(footer string) *ModalBuilder {
    mb.config.Footer = footer
    return mb
}

func (mb *ModalBuilder) Width(width int) *ModalBuilder {
    mb.config.Width = width
    return mb
}

func (mb *ModalBuilder) MaxWidth(maxWidth int) *ModalBuilder {
    mb.config.MaxWidth = maxWidth
    return mb
}

func (mb *ModalBuilder) Build(styles Styles, viewportWidth, viewportHeight int) string {
    return RenderModal("", mb.config, styles, viewportWidth, viewportHeight)
}

func (mb *ModalBuilder) BuildOnContent(baseContent string, styles Styles, viewportWidth, viewportHeight int) string {
    modal := RenderModal("", mb.config, styles, viewportWidth, viewportHeight)
    return CenterOverlay(baseContent, modal, viewportWidth, viewportHeight)
}