#!/usr/bin/env Rscript

options(stringsAsFactors = FALSE)

if (!requireNamespace("ggplot2", quietly = TRUE)) {
  stop("Required package not installed: ggplot2")
}
library(ggplot2)

script_args <- commandArgs(trailingOnly = FALSE)
file_arg <- script_args[grepl("^--file=", script_args)][1]
if (length(file_arg) && !is.na(file_arg)) {
  script_path <- normalizePath(sub("^--file=", "", file_arg))
  repo_root <- normalizePath(file.path(dirname(script_path), ".."))
} else if (!exists("repo_root")) {
  repo_root <- normalizePath(".")
}
setwd(repo_root)

panel_file <- file.path("data", "releases", "party_2d_election_year_panel_v0.csv.gz")
output_dir <- file.path("validation", "outputs")
figure_dir <- file.path("validation", "figures")

if (!file.exists(panel_file)) stop("Required input not found: ", panel_file)
dir.create(output_dir, recursive = TRUE, showWarnings = FALSE)
dir.create(figure_dir, recursive = TRUE, showWarnings = FALSE)

panel <- read.csv(panel_file, check.names = FALSE)

trajectory_spec <- data.frame(
  party_id = c(1691, 432, 1375),
  series = c("Fidesz", "US Democrats", "CDU"),
  start_year = c(1990, 1988, 2002),
  end_year = c(2022, 2020, 2025)
)

trajectory_rows <- lapply(seq_len(nrow(trajectory_spec)), function(i) {
  spec <- trajectory_spec[i, ]
  d <- panel[
    panel$party_id == spec$party_id &
      panel$year >= spec$start_year & panel$year <= spec$end_year,
  ]
  if (!nrow(d)) stop("No trajectory rows found for PartyFacts ", spec$party_id)
  d$series <- spec$series
  d$display_role <- "trajectory"
  d$is_labelled <- d$year %in% c(spec$start_year, spec$end_year)
  d$label <- ifelse(d$is_labelled, paste(spec$series, d$year), "")
  d[order(d$year), ]
})
trajectories <- do.call(rbind, trajectory_rows)
trajectory_levels <- trajectory_spec$series
trajectories$series <- factor(trajectories$series, levels = trajectory_levels)

plot_columns <- c(
  "party_id", "party_name_english", "country", "year", "series",
  "display_role", "is_labelled", "label", "economic_lr",
  "economic_lr_q025", "economic_lr_q975", "galtan", "galtan_q025",
  "galtan_q975", "source_support_class"
)
plot_data <- trajectories[plot_columns]
write.csv(
  plot_data,
  file.path(output_dir, "party_scale_example_plot_data.csv"),
  row.names = FALSE,
  na = ""
)

labelled <- plot_data[plot_data$is_labelled, ]
label_positions <- data.frame(
  label = c(
    "Fidesz 1990", "Fidesz 2022",
    "US Democrats 1988", "US Democrats 2020",
    "CDU 2002", "CDU 2025"
  ),
  plot_label = c(
    "Fidesz\n1990", "Fidesz\n2022",
    "US Democrats\n1988", "US Democrats\n2020",
    "CDU\n2002", "CDU\n2025"
  ),
  label_x = c(.84, .36, .48, .35, .53, .72),
  label_y = c(.36, .93, .47, .27, .66, .57)
)
labelled <- merge(labelled, label_positions, by = "label", all.x = TRUE, sort = FALSE)
if (anyNA(labelled$label_x) || anyNA(labelled$label_y)) {
  stop("Missing manual label position for a displayed scale example")
}

p <- ggplot() +
  geom_path(
    data = trajectories,
    aes(x = economic_lr, y = galtan, group = series, colour = series, linetype = series),
    linewidth = .85,
    arrow = grid::arrow(type = "closed", length = grid::unit(.065, "inches"))
  ) +
  geom_errorbar(
    data = labelled,
    aes(x = economic_lr, ymin = galtan_q025, ymax = galtan_q975, colour = series),
    width = 0, alpha = .75
  ) +
  geom_errorbar(
    data = labelled,
    aes(y = galtan, xmin = economic_lr_q025, xmax = economic_lr_q975, colour = series),
    orientation = "y", width = 0, alpha = .75
  ) +
  geom_point(
    data = labelled,
    aes(x = economic_lr, y = galtan, colour = series, shape = series),
    size = 2.4
  ) +
  geom_segment(
    data = labelled,
    aes(x = economic_lr, y = galtan, xend = label_x, yend = label_y, colour = series),
    linewidth = .3, show.legend = FALSE
  ) +
  geom_text(
    data = labelled,
    aes(x = label_x, y = label_y, label = plot_label),
    size = 2.6, lineheight = .9
  ) +
  scale_linetype_manual(
    values = c("Fidesz" = "solid", "US Democrats" = "dotdash", "CDU" = "dashed"),
    breaks = trajectory_levels
  ) +
  scale_colour_manual(
    values = c("Fidesz" = "#D55E00", "US Democrats" = "#0072B2", "CDU" = "#009E73"),
    breaks = trajectory_levels
  ) +
  scale_shape_manual(
    values = c("Fidesz" = 16, "US Democrats" = 15, "CDU" = 17),
    breaks = trajectory_levels
  ) +
  scale_x_continuous(limits = c(0, 1), breaks = c(0, .25, .5, .75, 1)) +
  scale_y_continuous(limits = c(0, 1), breaks = c(0, .25, .5, .75, 1)) +
  labs(
    x = "Economic: left (0) to right (1)",
    y = "Cultural: cosmopolitan (0) to traditionalist (1)",
    colour = "Election-year path",
    linetype = "Election-year path",
    shape = "Election-year path"
  ) +
  theme_minimal(base_size = 9) +
  theme(
    panel.grid.minor = element_blank(),
    legend.position = "bottom",
    legend.title = element_text(face = "bold"),
    plot.margin = margin(7, 12, 7, 7)
  )

ggsave(
  file.path(figure_dir, "party_scale_examples.pdf"),
  p, width = 8.8, height = 6.0, device = cairo_pdf
)

message("Wrote validation/outputs/party_scale_example_plot_data.csv")
message("Wrote validation/figures/party_scale_examples.pdf")